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R. A. Avery 《Journal of Zoology》1966,149(2):115-121
Common lizards caught at two different localities in April-May, July and September, were dissected and their stomach contents identified. Spiders were the principal food, andHomoptera were important in the summer months. With the exception of some distastefulforms like ants and woodlice, the proportions of invertebrates on the ground and in stomachsshowed a fairly close correspondence. Food eaten by juveniles in September was similar tothat of the adults, but the mean size of items in each category was smaller. A wide range of invertebrates was taken, and it was concluded that selection of food was on the basis of its size, taste and speed of movement. 相似文献
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F. Avery Jones 《BMJ (Clinical research ed.)》1954,1(4874):1315-1316,1317
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D. Margaret Avery 《Historical Biology》2018,30(1-2):276-283
AbstractThe presence of large numbers of micromammalian remains near the Homo rhodesiensis (now H. heidelbergensis or H. sapiens) type cranium from the Broken Hill Mine near Kabwe was noted when it was discovered. Most of the remains seem to have been lost but a small sample was preserved in the palaeontology collections at the Natural History Museum, London. Over the years, this sample received preliminary inspections that resulted in various published and unpublished reports or identifications, copies of which were kept with the material. The unpublished reports are reproduced to place them on record and to complement the more complete annotated systematic list for the site now given. The present paper collates previous identifications, adds some previously unrecorded taxa and updates the taxonomy to conform to current thinking. The partial nature of the sample prevents a detailed interpretation of environmental conditions at the time of accumulation and there remains no direct dating of the site. However, the micromammals suggest that the environment at the time of deposition was much as it would have been before mining and other human activities altered the vegetation, which may imply interglacial conditions. 相似文献
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Mutations in the alpha1 subunit of an L-type voltage-activated Ca2+ channel cause myotonia in Caenorhabditis elegans. 总被引:4,自引:0,他引:4
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The control of excitable cell action potentials is central to animal behavior. We show that the egl-19 gene plays a pivotal role in regulating muscle excitation and contraction in the nematode Caenorhabditis elegans and encodes the alphal subunit of a homologue of vertebrate L-type voltage-activated Ca2+ channels. Semi-dominant, gain-of-function mutations in egl-19 cause myotonia: mutant muscle action potentials are prolonged and the relaxation delayed. Partial loss-of-function mutations cause slow muscle depolarization and feeble contraction. The most severe loss-of-function mutants lack muscle contraction and die as embryos. We localized two myotonic mutations in the sixth membrane-spanning domain of the first repeat (IS6) region, which has been shown to be responsible for voltage-dependent inactivation. A third myotonic mutation implicates IIIS4, a region involved in sensing plasma-membrane voltage change, in the inactivation process. 相似文献
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J M Farley C H Romero M G Spalding M L Avery D J Forrester 《Journal of wildlife diseases》2001,37(4):808-812
In order to understand the epidemiology of Newcastle disease (ND) outbreaks in double-crested cormorants (Phalacrocorax auritus), a study was conducted on wintering migratory cormorants (P. a. auritus) in Alabama and Mississippi (USA) and non-migratory cormorants (P. a. floridanus) that breed in Florida (USA). Antibodies against ND virus were detected by the hemagglutination-inhibition method in sera from 86 of 183 (47%) migratory cormorants over-wintering in eight roosting sites in Alabama and Mississippi between November, 1997 and April, 1999. Titers ranged from 5 to 40. Antibody prevalences in sera collected from females in early winter (November and December) (26%) and late winter (February and March) (56%) were significantly different (P = 0.0007). None of 45 serum samples from 1- to 7-wk-old nestlings from 11 colonies in Florida during the 1997-98 and 1998-99 breeding seasons was positive. However, antibodies were detected in yolk samples from 98 of 126 (78%) eggs collected in these same colonies. Titers ranged from 4 to 256. The prevalence of antibodies in eggs collected from fresh-water colonies (63% prevalence, n = 30) and salt-water colonies (82% prevalence, n = 96) was significantly different (P = 0.041). ND virus was not isolated from tissues of 18 cormorants and cloacal and tracheal swabs from 202 cormorants collected in Alabama and Mississippi; virus was also not isolated from cloacal and tracheal swabs from 51 nestlings from Florida. 相似文献
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