Norway rat

ドブネズミ

関

laboratory rat、rat、Rattus、Rattus norvegicus

WordNet

1. common house rats; upper incisors have a beveled edge (同)genus Rattus
2. give (hair) the appearance of being fuller by using a rat
3. a pad (usually made of hair) worn as part of a womans coiffure
4. any of various long-tailed rodents similar to but larger than a mouse
5. catch rats, especially with dogs
6. desert ones party or group of friends, for example, for ones personal advantage
7. employ scabs or strike breakers in
8. a constitutional monarchy in northern Europe on the western side of the Scandinavian Peninsula; achieved independence from Sweden in 1905 (同)Kingdom of Norway, Norge, Noreg
9. standing or position on a scale
10. a local tax on property (usually used in the plural)

PrepTutorEJDIC

1. 『ネズミ』 / ひきょう者,裏切り者 / ネズミをつかまえる / 《話》(人を)裏切る,密告する《+『on』+『名』〈人〉》
2. ノルウェー(スカンジナビア半島の西半分を占める王国;首都はOslo)
3. 〈C〉〈U〉（品質・技量などによる）格づけ,評価 / 〈C〉（個人・会社の経済的な）信用度 / 〈C〉(トン・馬力による)(船舶・車)の等級 / 〈C〉(テレビ・ラジオの)視聴率
4. ばかな,信じられない

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/12/03 21:50:26」(JST)

wiki en

[Wiki en表示]

"Rattus norvegicus" and "Sewer Rat" redirect here. For the album, see Rattus Norvegicus (album). For the roller coaster, see Sewer Rat (roller coaster).

Brown rat
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Mammalia
Order:	Rodentia
Family:	Muridae
Subfamily:	Murinae
Genus:	Rattus
Species:	R. norvegicus
Binomial name
Rattus norvegicus (Berkenhout, 1769)
Brown rat range

The brown rat, common rat, street rat, sewer rat, Hanover rat, Norway rat, brown Norway rat, Norwegian rat, wharf rat (Rattus norvegicus), or hood rat is one of the best known and most common rats.

One of the largest muroids, it is a brown or grey rodent with a body up to 25 cm (10 in) long, and a similar tail length; the male weighs on average 350 g (12 oz) and the female 250 g (9 oz). Thought to have originated in northern China, this rodent has now spread to all continents except Antarctica, and is the dominant rat in Europe and much of North America—making it by at least this particular definition the most "successful" mammal on the planet after humans. Indeed, with rare exceptions, the brown rat lives wherever humans live, particularly in urban areas.

Selective breeding of Rattus norvegicus has produced the laboratory rat, a model organism in biological research, as well as pet rats.

Naming and etymology

Originally called the "Hanover rat" by people wishing to link problems in 18th century England with the House of Hanover, it is not known for certain why the brown rat is named Rattus norvegicus (Norwegian rat), as it did not originate from Norway. However, the English naturalist John Berkenhout, author of the 1769 book Outlines of the Natural History of Great Britain, is most likely responsible for popularizing the misnomer. Berkenhout gave the brown rat the binomial name Rattus norvegicus, believing it had migrated to England from Norwegian ships in 1728, although no brown rat had entered Norway at that time.

By the early to middle part of the 19th century, British academics were aware that the brown rat was not native to Norway, hypothesizing (incorrectly) that it may have come from Ireland, Gibraltar or across the English Channel with William the Conqueror. As early as 1850, however,a more correct understanding of the rat's origins was beginning to develop. The British novelist Charles Dickens acknowledged the misnomer in his weekly journal, All the Year Round, writing:

"Now there is a mystery about the native country of the best known species of rat, the common brown rat. It is frequently called, in books and otherwise, the 'Norway rat', and it is said to have been imported into this country in a ship-load of timber from Norway. Against this hypothesis stands the fact that when the brown rat had become common in this country, it was unknown in Norway, although there was a small animal like a rat, but really a lemming, which made its home there."

Academics began to understand the origins and corrected etymology of the brown rat towards the end of the 19th century, as seen in the 1895 text Natural History by American scholar Alfred Henry Miles:

"The brown rat is the species common in England, and best known throughout the world. It is said to have travelled from Persia to England less than two hundred years ago and to have spread from thence to other countries visited by English ships."

Though the assumptions surrounding this species' origins were not yet entirely accurate, by the 20th century, it was established among naturalists that the brown rat did not originate in Norway, rather the species came from central Asia and (likely) China. Despite this, this species' common name of "Norway rat" is still in use today.

Description

Comparison of the physique of a black rat (Rattus rattus) with a brown rat (Rattus norvegicus)

The fur is coarse and usually brown or dark grey, while the underparts are lighter grey or brown. The length can be up to 25 cm (10 in), with the tail a further 25 cm (10 in), the same length as the body. Adult body weight averages 550 g (19 oz) in males and about 350 g (12 oz) in females, but a very large individual can reach 900 g (32 oz). Rats weighing over 1 kg (2.2 lb) are exceptional, and stories of rats as big as cats are exaggerations, or misidentifications of other rodents, such as the coypu and muskrat.

Brown rats have acute hearing, are sensitive to ultrasound, and possess a very highly developed olfactory sense. Their average heart rate is 300 to 400 beats per minute, with a respiratory rate of around 100 per minute. The vision of a pigmented rat is poor, around 20/600, while a non-pigmented (albino) with no melanin in its eyes has both around 20/1200 vision and a terrible scattering of light within its vision. Brown rats are dichromates which perceive colors rather like a human with red-green colorblindness, and their colour saturation may be quite faint. Their blue perception, however, also has UV receptors, allowing them to see ultraviolet lights that some species cannot.

Biology and behavior

Brown rat skull

The brown rat is nocturnal and is a good swimmer, both on the surface and underwater, but unlike the related black rat (Rattus rattus), it is a poor climber. Brown rats dig well, and often excavate extensive burrow systems. A 2007 study found brown rats to possess metacognition, a mental ability previously only found in humans and some primates, but further analysis suggested they may have been following simple operant conditioning principles.

Communication

Brown rats are capable of producing ultrasonic vocalizations. As pups, young rats use different types of ultrasonic cries to elicit and direct maternal search behavior, as well as to regulate their mother's movements in the nest. Although pups will produce ultrasounds around any other rats at 7 days old, by 14 days old they significantly reduce ultrasound production around male rats as a defensive response. Adult rats will emit ultrasonic vocalizations in response to predators or perceived danger; the frequency and duration of such cries depends on the sex and reproductive status of the rat. The female rat will also emit ultrasonic vocalizations during mating.

Chirping

Rats may also emit short, high frequency, ultrasonic, socially induced vocalization during rough and tumble play, before receiving morphine, or mating, and when tickled. The vocalization, described as a distinct "chirping", has been likened to laughter, and is interpreted as an expectation of something rewarding. Like most rat vocalizations, the chirping is too high in pitch for humans to hear without special equipment. Bat detectors are often used by pet owners for this purpose.

In clinical studies, the chirping is associated with positive emotional feelings, and social bonding occurs with the tickler, resulting in the rats becoming conditioned to seek the tickling. However, as the rats age, the tendency to chirp appears to decline.

Rat chirp also can be used for mosquito control.^{[citation needed]}

Other ultrasonic vocalizations, including a lower-frequency 'boom' or 'whoom' noise can be produced by bucks in a calm state, when grooming or settling down to sleep.^{[citation needed]}

Audible communication

Brown rats also produce communicative noises capable of being heard by humans. The most commonly heard in domestic rats is bruxing, or teeth-grinding, which is most usually triggered by happiness, but can also be 'self-comforting' in stressful situations, such as a visit to the vet. The noise is best described as either a quick clicking or 'burring' sound, varying from animal to animal.

In addition, they commonly squeak along a range of tones from high, abrupt pain squeaks to soft, persistent 'singing' sounds during confrontations.

Diet

The brown rat is a true omnivore and will consume almost anything, but cereals form a substantial part of its diet.

Brown rat eating sunflower seeds

Martin Schein, founder of the Animal Behavior Society in 1964, studied the diet of brown rats and came to the conclusion that the most-liked foods of brown rats include scrambled eggs, macaroni and cheese, and cooked corn kernels. According to Schein, the least-liked foods were raw beets, peaches, and raw celery.

Foraging behavior is often population-specific, and varies by environment and food source. Brown rats living near a hatchery in West Virginia catch fingerling fish. Some colonies along the banks of the Po River in Italy will dive for mollusks, a practice demonstrating social learning among members of this species. Rats on the island of Norderoog in the North Sea stalk and kill sparrows and ducks.

Reproduction and life cycle

The brown rat can breed throughout the year if conditions are suitable, with a female producing up to five litters a year. The gestation period is only 21 days, and litters can number up to 14, although seven is common. They reach sexual maturity in about five weeks. The maximum life span is up to three years, although most barely manage one. A yearly mortality rate of 95% is estimated, with predators and interspecies conflict as major causes.

When lactating, female rats display a 24-hour rhythm of maternal behavior, and will usually spend more time attending to smaller litters than large ones.

Brown rats live in large, hierarchical groups, either in burrows or subsurface places, such as sewers and cellars. When food is in short supply, the rats lower in social order are the first to die. If a large fraction of a rat population is exterminated, the remaining rats will increase their reproductive rate, and quickly restore the old population level.^{[citation needed]}

Social behavior

Rats commonly groom each other and sleep together. As with dogs, rats create a social hierarchy, and each rat has its own place in the pack. Rats are said to establish an order of hierarchy, so one rat will be dominant over another one. Groups of rats tend to "play fight", which can involve any combination of jumping, chasing, tumbling, and "boxing". Play fighting involves rats going for each other's necks, while serious fighting involves strikes at the others' back ends. If living space become limited, rats may turn to aggressive behavior, which may result in the death of some animals, reducing the burden over the living space.

Rats like most mammals also form family groups, a mother and her young. This applies to both groups of males and females. However, rats are territorial animals, meaning that they usually act aggressively or scared of strange rats. Rats will fluff up their hair, hiss, squeal, and move their tails around when defending their territory. Rats will chase each other, groom each other, sleep in group nests, wrestle with each other, have dominance squabbles, communicate, and play in various other ways with each other. Huddling is an additional important part of rat socialization. Huddling is often supposed to have a heat-conserving function. Nestling rats especially depend on heat from their mother, since they cannot regulate their own temperature. Huddling is an extreme form of herding. Other forms of interaction include, crawling under, which is literally the act of crawling underneath one another,walking over, also explained in the name, then there is allo-grooming, so-called to distinguish it from self-grooming. And lastly there is another type of contact called nosing, where a rat gently pushes with its nose at another rat near the neck.

Burrowing

Rats are known to burrow extensively, both in the wild and in captivity, if given access to a suitable substrate. Rats generally begin a new burrow adjacent to an object or structure, as this provides a sturdy "roof" for the section of the burrow nearest to the ground's surface. Burrows usually develop to eventually include multiple levels of tunnels, as well as a secondary entrance. Older male rats will generally not burrow, while young males and females will burrow vigorously.

Burrows provide rats with shelter and food storage, as well as safe, thermo-regulated nest sites. Rats use their burrows to escape from perceived threats in the surrounding environment; for example, rats will retreat to their burrows following a sudden, loud noise or while fleeing an intruder. Burrowing can therefore be described as a "pre-encounter defensive behavior", as opposed to a "post-encounter defensive behavior", such as flight, freezing, or avoidance of a threatening stimulus.

Distribution and habitat

Likely originating from the plains of Asia, northern China and Mongolia, the brown rat spread to other parts of the world sometime in the Middle Ages. The question of when brown rats became commensal with humans remains unsettled, but as a species, they have spread and established themselves along routes of human migration and now live almost everywhere humans are. .

The brown rat may have been present in Europe as early as 1553, a conclusion drawn from an illustration and description by Swiss naturalist Conrad Gesner in his book Historiae animalium, published 1551–1558. Though Gesner's description could apply to the black rat, his mention of a large percentage of albino specimens—not uncommon among wild populations of brown rats—adds credibility to this conclusion. Reliable reports dating to the 18th century document the presence of the brown rat in Ireland in 1722, England in 1730, France in 1735, Germany in 1750, and Spain in 1800, becoming widespread during the Industrial Revolution. It did not reach North America until around 1750–1755.

As it spread from Asia, the brown rat generally displaced the black rat in areas where humans lived. In addition to being larger and more aggressive, the change from wooden structures and thatched roofs to bricked and tiled buildings favored the burrowing brown rats over the arboreal black rats. In addition, brown rats eat a wider variety of foods, and are more resistant to weather extremes.

In the absence of humans, brown rats prefer damp environments, such as river banks. However, the great majority are now linked to man-made environments, such as sewage systems.

Brown rat in a flower box in the East Village of New York City

It is often said that there are as many rats in cities as people, but this varies from area to area depending on climate, living conditions, etc. Brown rats in cities tend not to wander extensively, often staying within 20 m (66 ft) of their nest if a suitable concentrated food supply is available, but they will range more widely where food availability is lower. There is great debate over the size of the population of rats in New York City, with estimates from almost 100 million rats to as few as 250,000. Experts suggest New York is a particularly attractive place for rats because of its aging infrastructure, high moisture and poverty rates. In addition to sewers, rats are very comfortable living in alleyways and residential buildings, as there is usually a large and continuous food source in those areas.

In the United Kingdom, some figures show the rat population has been rising, with estimations that 81 million rats reside in the UK. Those figures would mean there are 1.3 rats per person in the country. High rat populations in the UK are often attributed to the mild climate, which allow them higher survival rates during the winter months.

The only brown rat-free zones in the world are the Arctic, the Antarctic, some especially isolated islands, such as Iceland, the province of Alberta in Canada, and certain conservation areas in New Zealand.

Antarctica is almost completely covered by ice and has no permanent human inhabitants, making it uninhabitable by rats. The Arctic has extremely cold winters that rats cannot survive outdoors, and the human population density is extremely low, making it difficult for rats to travel from one habitation to another. When the occasional rat infestation is noticed and eliminated, the rats are unable to reinfest it from an adjacent one. Isolated islands are also able to eliminate rat populations because of low human population density and geographic distance from other rat populations.

Alaska

Rat Island in Alaska was infested with brown rats after a Japanese shipwreck in 1780. They had a devastating effect on the native bird life. An eradication program was started in 2007 and the island was declared rat free in June 2009.

Alberta, Canada

Alberta, Canada, is unusual in that rat infestation was eliminated by aggressive government action. Although it is a major agricultural area, it is far from any seaport and only a portion of its eastern boundary with Saskatchewan provides a favorable entry route for rats. They cannot survive in the boreal forest to the north, the Rocky Mountains to the west, nor the semiarid High Plains of Montana to the south. The first brown rat did not reach Alberta until 1950, and in 1951, the province launched a rat-control program that included shooting and poisoning rats, and bulldozing, burning down, and blowing up rat-infested buildings. The effort was backed by legislation that required every person and every municipality to destroy and prevent the establishment of designated pests. If they failed, the provincial government could carry out the necessary measures and charge the costs to the landowner or municipality.

In the first year of the program, 64 tonnes (71 short tons) of arsenic trioxide were spread throughout 8,000 buildings on farms along the Saskatchewan border. In 1953, the much less toxic and more effective poison, warfarin, was introduced. By 1960, the number of rat infestations in Alberta dropped to below 200 per year.

Currently, only zoos, universities, and research institutes are allowed to own caged rats in Alberta, and possession of an unlicensed rat (including pet rats) is punishable by a $5,000 fine or 60 days in jail. The adjacent and similarly landlocked province of Saskatchewan initiated a rat control program in 1972, and has managed to reduce the number of rats in the province substantially, although they have not been eliminated.

New Zealand

First arriving before 1800 (perhaps on James Cook's vessels), brown rats have posed a serious threat to many of New Zealand's native animals. Rat eradication programmes within New Zealand have led to rat-free zones on offshore islands and even on fenced "ecological islands" on the mainland. Before an eradication effort was launched in 2001, the sub-Antarctic Campbell Island had the highest population density of brown rats in the world.

Diseases

Similar to other rodents, brown rats may carry a number of pathogens, which can result in disease, including Weil's disease, rat bite fever, cryptosporidiosis, viral hemorrhagic fever, Q fever and hantavirus pulmonary syndrome. In the United Kingdom, brown rats are an important reservoir for Coxiella burnetii, the bacterium that causes Q fever, with seroprevalence for the bacteria found to be as high as 53% in some wild populations.

This species can also serve as a reservoir for Toxoplasma gondii, the parasite that causes toxoplasmosis, though the disease usually spreads from rats to humans when domestic cats feed on infected brown rats. The parasite has a long history with the brown rat, and there are indications that the parasite has evolved to alter an infected rat's perception to cat predation, making it more susceptible to predation and increasing the likelihood of transmission.

Surveys and specimens of brown rat populations throughout the world have shown this species is often associated with outbreaks of trichinosis, but the extent to which the brown rat is responsible in transmitting Trichinella larvae to humans and other synanthropic animals is at least somewhat debatable. Trichinella pseudospiralis, a parasite previously not considered to be a potential pathogen in humans or domestic animals, has been found to be pathogenic in humans and carried by brown rats.

Brown rats are sometimes mistakenly thought to be a major reservoir of bubonic plague, a possible cause of the Black Death. However, the bacterium responsible, Yersinia pestis, is commonly endemic in only a few rodent species and is usually transmitted zoonotically by rat fleas—common carrier rodents today include ground squirrels and wood rats. However, brown rats may suffer from plague, as can many nonrodent species, including dogs, cats, and humans. The original carrier for the plague-infected fleas thought to be responsible for the Black Death was the black rat, and it has been hypothesized that the displacement of black rats by brown rats led to the decline of bubonic plague. This theory has, however, been deprecated, as the dates of these displacements do not match the increases and decreases in plague outbreaks.

Control

Some of the common methods used to control the number of Brown rats include:

Trapping

Using traditional break-back traps, glue traps, live cage traps and other humane traps, such as guns and gas

Poisoning

There are many types of poison available for the purpose of controlling the Brown rat. The use of poison is controlled in most of the countries in the world so it is important to check local laws.

Proofing

Prevention is the best cure. There are ways to stop the infestation occurring at the first place, such as blocking access points, better waste management, better sewage design.

In captivity

Uses in science

Main article: Laboratory rat

Selective breeding of albino brown rats rescued from being killed in a now-outlawed sport called rat baiting has produced the albino laboratory rat. Like mice, these rats are frequently subjects of medical, psychological and other biological experiments, and constitute an important model organism. This is because they grow quickly to sexual maturity and are easy to keep and to breed in captivity. When modern biologists refer to "rats", they almost always mean Rattus norvegicus.

As pets

Main article: Fancy rat

The brown rat is kept as a pet in many parts of the world. Australia, the United Kingdom, and the United States are just a few of the countries that have formed fancy rat associations similar in nature to the American Kennel Club, establishing standards, orchestrating events, and promoting responsible pet ownership.

The many different types of domesticated brown rats include variations in coat patterns, as well as the style of the coat, such as Hairless or Rex, and more recently developed variations in body size and structure, including dwarf and tailless fancy rats.

References

External links

Overviews

• Rat behaviour and biology A detailed set of pages by biologist Anne Hanson
• Norway (Brown) Rat Fact sheet including information on habits, habitat, threats and prevention tips
• Rattus norvegicus at the University of Michigan Museum of Zoology
• Life cycle data sheet for Rattus norvegicus written by biologist João Pedro de Magalhães
• Rats and Mice: Overview Online version of the Merck veterinary manual
• ARKive Still photos and videos
• Wild rats – the world's first website and forum (English interface is available) about wild rats, it is the home of a unique interactive JavaScript rat. The English version is expected to be available in 2010.
• Brown rat information page from the EX-PEST website

Rattus norvegicus genome and use as model animal

• Nature: Rat Genome
• Rat genome database
• View the rat genome in Ensembl

UpToDate Contents

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English Journal

• Baccharis trimera improves the antioxidant defense system and inhibits iNOS and NADPH oxidase expression in a rat model of inflammation.

• Cruz Padua Bd, Rossoni Junior JV, de Brito Magalhaes CL, Seiberf JB, Araujo CM, Bianco de Souza GH, Chaves MM, Silva ME, Pedrosa ML, Costa DC1.Author information 1Programa de Pos-graduacao em Ciencias Biologicas do Nucleo de Pesquisas em Ciencias Biologicas - NUPEB; Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, 35.400-000, Brasil. dani.caldeiracosta@gmail.com.AbstractAcetaminophen is a common analgesic and antipyretic compound which, when administered in high doses, has been associated with significant morbidity and mortality, secondary to hepatic toxicity. Although this may be due to a direct interaction of reactive acetaminophen metabolites with hepatocyte proteins, recent studies have suggested that reactive species produced by neutrophils also contribute to the pathophysiological process. Researches on the chemical composition of B. trimera show that this plant has bioactive compounds such as flavonoids, related to the organism's protection against free radicals. Therefore, in the present study, using Fischer rats, the effect of B. trimera on the antioxidant defense system, the production of nitric oxide (NO) and on the expression of nitric oxide synthase (iNOS), superoxide dismutase (SOD), catalase (CAT) and of the subunits of the NADPH oxidase in neutrophils was evaluated in a model of phagocytosis induced by zimosan (ZC3b) and in a model of inflammation induced by acetaminophen. The results show that the treatment with B. trimera improves the defense system of antioxidant and restores the balance ROS / NO that is altered in the inflammatory process induced by APAP. In conclusion, B. trimera extracts exert antioxidant properties by scavenging ROS and decrease the expression of genes responsible by reactive species production in neutrophils.
• Current pharmaceutical biotechnology.Curr Pharm Biotechnol.2014 Nov;14(11):975-84.
• Acetaminophen is a common analgesic and antipyretic compound which, when administered in high doses, has been associated with significant morbidity and mortality, secondary to hepatic toxicity. Although this may be due to a direct interaction of reactive acetaminophen metabolites with hepatocyte pro
• PMID 24372242

• Differential toxicological response to positively and negatively charged nanoparticles in the rat brain.

• Knudsen KB1, Northeved H, Ek PK, Permin A, Andresen TL, Larsen S, Wegener KM, Lam HR, Lykkesfeldt J.Author information 1Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark.AbstractWe investigated the potential for systemic and local toxicity after administration of empty nanosized anionic and cationic PEGylated-micelles and non-PEGylated liposomes, without a ligand attached, intended for use in drug-delivery systems. The particles were administered to 5-6-week-old male rats by three intravenous (IV) administrations over a period of one week at a dose of 100 mg/kg bodyweight or after a single intracerebroventricular (ICV) injection at a dose of 50 µg. The particles were stable and well characterised with respect to size and zeta potential. ICV administration of cationic particles was associated with histological changes near the injection site (hippocampus). Here, we detected focal infiltration with phagocytic cells, loss of neurons and apoptotic cell death, which were not observed after administration of the vehicle. No significant difference was found after IV or ICV administration of the anionic micelles with regard to haematology, clinical chemistry parameters or at the pathological examinations, as compared to control animals. Our study suggests that ICV delivery of cationic particles to the brain tissue is associated with toxicity at the injection site.
• Nanotoxicology.Nanotoxicology.2014 Nov;8(7):764-74. doi: 10.3109/17435390.2013.829589.
• We investigated the potential for systemic and local toxicity after administration of empty nanosized anionic and cationic PEGylated-micelles and non-PEGylated liposomes, without a ligand attached, intended for use in drug-delivery systems. The particles were administered to 5-6-week-old male rats b
• PMID 23889261

• In vitro cytotoxicity and bioavailability of solid lipid nanoparticles containing tamoxifen citrate.

• Hashem FM1, Nasr M, Khairy A.Author information 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Helwan University , Cairo , Egypt and.AbstractThe objective of this study was to evaluate the influence of solid lipid nanoparticles (SLN) loaded with the poorly water-soluble drug tamoxifen citrate (TC) on the in vitro antitumor activity and bioavailability of the drug. TC-loaded SLN were prepared by solvent injection method using glycerol monostearate (GMS) or stearic acid (SA) as lipid matrix. Poloxamer 188 or tween 80 were used as stabilizers. TC-loaded SLN (F3 and F4) prepared using GMS and stabilized by poloxamer 188 showed highest entrapment efficiency % (86.07 ± 1.74 and 90.40 ± 1.22%) and reasonable mean particle sizes (130.40 ± 9.45 and 243.80 ± 12.33 nm), respectively. The in vitro release of TC from F3 and F4 exhibited an initial burst effect followed by a sustained drug release. In vitro cytotoxicity of F3 against human breast cancer cell line MCF-7 showed comparable antitumor activity to free drug. Moreover, the results of bioavailability evaluation of TC-loaded SLN in rats compared to free TC indicated that 160.61% increase in the oral bioavailability of TC. The obtained results suggest that incorporation of the poorly water-soluble drug TC in SLN preserves the in vitro antitumor activity and significantly enhance oral bioavailability of TC in rats.
• Pharmaceutical development and technology.Pharm Dev Technol.2014 Nov;19(7):824-32. doi: 10.3109/10837450.2013.836218. Epub 2013 Sep 13.
• The objective of this study was to evaluate the influence of solid lipid nanoparticles (SLN) loaded with the poorly water-soluble drug tamoxifen citrate (TC) on the in vitro antitumor activity and bioavailability of the drug. TC-loaded SLN were prepared by solvent injection method using glycerol mon
• PMID 24032414

Japanese Journal

• The intraspecies relationship between tissue turnover and metabolic rate in rats

• Kraeer Kimberly,Arneson Lynne S.,MacAvoy Stephen E.
• Ecological research 29(5), 937-947, 2014-09
• NAID 40020214823

• 東日本大震災津波被災地の一瓦礫置き場で捕獲されたドブネズミの胃内容物

• 矢部 辰男,石川 善大
• ペストロジー 29(1), 19-21, 2014-05-15
• 東日本大震災から2年以上を経た宮城県内の被災地で,瓦礫置き場に生息するドブネズミの胃内容物を調べた.瓦礫置き場内を流れる水路脇で得られた3個体のドブネズミの胃内容物から,腹足類とミミズ類,および葉・茎の組織が見いだされた.これらの食物は湿地周囲に豊富であると思われる.したがって,瓦礫置き場にある水路や湿地は,ドブネズミに生息地を提供する.
• NAID 110009810477

• 東日本大震災津波被災地の一瓦礫置き場で捕獲されたドブネズミの胃内容物

• 矢部 辰男,石川 善大
• ペストロジー 29(1), 19-21, 2014-05
• NAID 40020102447

Related Links

• Brown rat - Wikipedia, the free encyclopedia

The brown rat, common rat, street rat, sewer rat, Hanover rat, Norway rat, brown Norway rat, Norwegian rat, or wharf rat (Rattus norvegicus) is one of the best known and most common rats. One of the largest muroids, it is a brown or grey ...

Related Pictures

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★リンクテーブル★

リンク元	「Rattus」「Rattus norvegicus」「ドブネズミ」「laboratory rat」
関連記事	「rat」「Norway」

「Rattus」

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クマネズミ属、ラッタス属、Rattus属

関

laboratory rat、Norway rat、rat、Rattus norvegicus

　

「Rattus norvegicus」

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• (学名)(げっ歯類)ラット、ドブネズミ

関

laboratory rat、Norway rat、rat、Rattus

「ドブネズミ」

　　[★]

英

Norway rat、Rattus norvegicus

関

ラット、クマネズミ属、実験用ラット

「laboratory rat」

　　[★]

• 実験用ラット

関

Norway rat、rat、Rattus、Rattus norvegicus

「rat」

　　[★]

• n.

• (げっ歯類)ラット、(マウスも含めての総称)ネズミ、ラットの

関

laboratory rat、mouse、Norway rat、Rattus、Rattus norvegicus

　 　 　 　 　 　 　

「Norway」

　　[★]

• ノルウェー

関

Norwegian