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161.
162.
Generation and cryopreservation of transgenic mice depend on reliable and continuous production of pre-implantation embryos. To suppress circannual and circadian rhythms driving the physiological and sexual behaviour of free living animals, laboratory animals are housed under standardized conditions. It remains to be elucidated if the artificial climate can cover all environmental effects. Here, we report that the humidity in an animal facility affects the embryo yield. The weather at the location of the facility, especially the temperature, influences the climate within an animal facility; weather peaks are obviously covered in part only, even if the facility is equipped with a powerful air-conditioning supply. Subsequently, external weather changes interact with the environment within the facility, influencing the production of embryos. Furthermore, noise and/or vibrations as generated by construction works, negatively affect the embryo yield. 相似文献
163.
Erik Volz Verity Hill John T. McCrone Anna Price David Jorgensen Áine O’Toole Joel Southgate Robert Johnson Ben Jackson Fabricia F. Nascimento Sara M. Rey Samuel M. Nicholls Rachel M. Colquhoun Ana da Silva Filipe James Shepherd David J. Pascall Rajiv Shah Natasha Jesudason Thomas R. Connor 《Cell》2021,184(1):64-75.e11
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164.
Simon D. W. Frost Erik M. Volz 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1548):1879-1890
Information on the dynamics of the effective population size over time can be obtained from the analysis of phylogenies, through the application of time-varying coalescent models. This approach has been used to study the dynamics of many different viruses, and has demonstrated a wide variety of patterns, which have been interpreted in the context of changes over time in the ‘effective number of infections’, a quantity proportional to the number of infected individuals. However, for infectious diseases, the rate of coalescence is driven primarily by new transmissions i.e. the incidence, and only indirectly by the number of infected individuals through sampling effects. Using commonly used epidemiological models, we show that the coalescence rate may indeed reflect the number of infected individuals during the initial phase of exponential growth when time is scaled by infectivity, but in general, a single change in time scale cannot be used to estimate the number of infected individuals. This has important implications when integrating phylogenetic data in the context of other epidemiological data. 相似文献
165.
Santos PS Füst G Prohászka Z Volz A Horton R Miretti M Yu CY Beck S Uchanska-Ziegler B Ziegler A 《Genetic testing》2008,12(4):481-486
Smoking behavior has been associated in two independent European cohorts with the most common Caucasian human leukocyte antigen (HLA) haplotype (A1-B8-DR3). We aimed to test whether polymorphic members of the two odorant receptor (OR) clusters within the extended HLA complex might be responsible for the observed association, by genotyping a cohort of Hungarian women in which the mentioned association had been found. One hundred and eighty HLA haplotypes from Centre d'Etude du Polymorphisme Humain families were analyzed in silico to identify single-nucleotide polymorphisms (SNPs) within OR genes that are in linkage disequilibrium with the A1-B8-DR3 haplotype, as well as with two other haplotypes indirectly linked to smoking behavior. A nonsynonymous SNP within the OR12D3 gene (rs3749971(T)) was found to be linked to the A1-B8-DR3 haplotype. This polymorphism leads to a (97)Thr --> Ile exchange that affects a putative ligand binding region of the OR12D3 protein. Smoking was found to be associated in the Hungarian cohort with the rs3749971(T) allele (p = 1.05 x 10(-2)), with higher significance than with A1-B8-DR3 (p = 2.38 x 10(-2)). Our results link smoking to a distinct OR allele, and demonstrate that the rs3749971(T) polymorphism is associated with the HLA haplotype-dependent differential recognition of cigarette smoke components, at least among Caucasian women. 相似文献
166.
Nuclear behavior during ascus development inChaetomium globosum was studied with the use of acetocarmine and aceto-orcein staining techniques. The chromosome behavior, including centriolar bodies and asynchronous disjunction of chromosomes, agreed with the basic pattern reported in Ascomycetes (Olive, 1965). The haploid chromosome complement of this strain appeared to be 6. 相似文献
167.
Summary Compatible strains of Schizophyllum commune Fr. were grown on a minimal medium with adjustments in the CO2 level and the carbon source. Acetate with glucose initiated reduced stipes and pilei of fruit-bodies, and changed lamellar cell structure. Sealed growth chambers increased CO2 levels and inhibited basidiocarp formation while growth of dense hyphal aggregates in the dikaryotic mycelium was stimulated. 相似文献
168.
Summary Sclerotia of Coprinus lagopus were produced in the laboratory and observed microscopically from initiation to maturity. Isolated bulbous hyphal cells appeared below or on the agar surface as the primary sclerotial initials. Short interhyphal cells had expanded lateral walls and increased in number at their isolated locations, and were surrounded by a thick network of normal mycelium. Increasing in numbers, the bulbous cells developed a tightly compact colony devoid of agar if submerged below the agar surface and lacked normal hyphal filaments. The outer cells thickened formed cell lumina and developed as a protective rind to the mature sclerotium. 相似文献
169.
Myriam Mirza Cornelia Volz Marcus Karlstetter Monica Langiu Aleksandra Somogyi Mika O. Ruonala Ernst R. Tamm Herbert J?gle Thomas Langmann 《PloS one》2013,8(10)
Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative lysosomal storage disorders characterized by vision loss, mental and motor deficits, and spontaneous seizures. Neuropathological analyses of autopsy material from NCL patients and animal models revealed brain atrophy closely associated with glial activity. Earlier reports also noticed loss of retinal cells and reactive gliosis in some forms of NCL. To study this phenomenon in detail, we analyzed the ocular phenotype of CLN6nclf mice, an established mouse model for variant-late infantile NCL. Retinal morphometry, immunohistochemistry, optokinetic tracking, electroretinography, and mRNA expression were used to characterize retinal morphology and function as well as the responses of Müller cells and microglia. Our histological data showed a severe and progressive degeneration in the CLN6nclf retina co-inciding with reactive Müller glia. Furthermore, a prominent phenotypic transformation of ramified microglia to phagocytic, bloated, and mislocalized microglial cells was identified in CLN6nclf retinas. These events overlapped with a rapid loss of visual perception and retinal function. Based on the strong microglia reactivity we hypothesized that dietary supplementation with immuno-regulatory compounds, curcumin and docosahexaenoic acid (DHA), could ameliorate microgliosis and reduce retinal degeneration. Our analyses showed that treatment of three-week-old CLN6nclf mice with either 5% DHA or 0.6% curcumin for 30 weeks resulted in a reduced number of amoeboid reactive microglia and partially improved retinal function. DHA-treatment also improved the morphology of CLN6nclf retinas with a preserved thickness of the photoreceptor layer in most regions of the retina. Our results suggest that microglial reactivity closely accompanies disease progression in the CLN6nclf retina and both processes can be attenuated with dietary supplemented immuno-modulating compounds. 相似文献
170.
Erik M. Volz Edward Ionides Ethan O. Romero-Severson Mary-Grace Brandt Eve Mokotoff James S. Koopman 《PLoS medicine》2013,10(12)