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141.
Hepatic and intestinal formation of polar sterols in vivo in animals fed on a cholesterol-supplemented diet.
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Measurements were made of the activities of the enzymes of the 'de novo' and salvage pathways of purine synthesis [phosphoribosyl pyrophosphate amidotransferase (EC 2.4.2.14), adenine phosphoribosyltransferase (EC 2.4.2.7) and hypoxanthine phosphoribosyltranferase (EC 2.4.2.8)] at different stages of the lactation cycle, and the effects of diabetes on the activity of these enzymes in lactation were studied. A distinctive pattern of enzyme change was observed, in which the 'de novo' pathway enzyme phosphoribosyl pyrophosphate amidotransferase increased sharply between days 10 and 14 of pregnancy, and then remained sensibly constant until the height of lactation, whereas the enzymes of the salvage pathway increased later in pregnancy and continued to rise during lactation. Diabetes severely depressed the activity of the enzymes of the salvage pathway, but appeared to be without effect on the 'de novo' pathway enzyme. These results are discussed in relation to the provision of purine precursors from tissues outside the mammary gland. 相似文献
142.
P P Calle R J Montali D L Janssen M K Stoskopf J D Strandberg 《Journal of wildlife diseases》1982,18(4):473-479
The necropsy files of the National Zoological Park and Baltimore Zoological Society were reviewed for cases of distal extremity necrosis (DEN) in birds. Nineteen cases of DEN occurred following either trauma or frostbite. Six birds developed an apparently primary type of DEN in which no predisposing factors were obvious clinically. The toes and feet were most commonly involved, and in several cases the beak was also affected. Some pathologic evidence is provided that certain cardiovascular lesions may predispose birds to DEN by compromising circulation of the extremities. 相似文献
143.
Jasmine Foo Lin L Liu Kevin Leder Markus Riester Yoh Iwasa Christoph Lengauer Franziska Michor 《PLoS computational biology》2015,11(9)
The traditional view of cancer as a genetic disease that can successfully be treated with drugs targeting mutant onco-proteins has motivated whole-genome sequencing efforts in many human cancer types. However, only a subset of mutations found within the genomic landscape of cancer is likely to provide a fitness advantage to the cell. Distinguishing such “driver” mutations from innocuous “passenger” events is critical for prioritizing the validation of candidate mutations in disease-relevant models. We design a novel statistical index, called the Hitchhiking Index, which reflects the probability that any observed candidate gene is a passenger alteration, given the frequency of alterations in a cross-sectional cancer sample set, and apply it to a mutational data set in colorectal cancer. Our methodology is based upon a population dynamics model of mutation accumulation and selection in colorectal tissue prior to cancer initiation as well as during tumorigenesis. This methodology can be used to aid in the prioritization of candidate mutations for functional validation and contributes to the process of drug discovery. 相似文献
144.
Zukang Feng John D. Westbrook Raul Sala Oliver S. Smart Gérard Bricogne Masaaki Matsubara Issaku Yamada Shinichiro Tsuchiya Kiyoko F. Aoki-Kinoshita Jeffrey C. Hoch Genji Kurisu Sameer Velankar Stephen K. Burley Jasmine Y. Young 《Structure (London, England : 1993)》2021,29(4):393-400.e1
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145.
Histidine kinases have been shown to mediate responses to endogenous and exogenous stimuli in organisms such as yeast, bacteria and plants. In the model plant Arabidopsis, histidine kinases have been shown to function in hormone signaling, and abiotic and biotic stress responses. More recently, the least characterized of the Arabidopsis histidine kinases, AHK5, was demonstrated to function in resistance toward the virulent bacterium Pseudomonas syringae pv tomato DC3000 (PstDC3000) and the necrotrophic fungus Botrytis cinerea, and as a negative regulator of tolerance toward salinity. Here, we present data which indicate that AHK5 also impacts on drought stress resistance and on the outcome of an incompatible interaction with avrRpm1-expressing PstDC3000 (PstDC3000 (avrRpm1)). We present a model which proposes a role for reactive oxygen species (ROS) and hormones in integrating abiotic and biotic stress responses via AHK5. 相似文献
146.
N. D. W. Lionel E. H. Mirando Jasmine C. Nanayakkara Priyani E. Soysa 《BMJ (Clinical research ed.)》1969,4(5679):340-341
Levamisole (the laevorotatory isomer of tetramisole) is a new synthetic anthelmintic. A cure rate of 91% was obtained in a series of 111 ascariasis-infected children treated with a single oral dose of the drug. The failures, who were treated with the drug a second time one week later, were all cured. In a comparative study of levamisole and piperazine citrate in a series of 100 children with ascariasis a cure rate of 92% and 90% was obtained with a single dose of levamisole and piperazine respectively, indicating equal efficacy. Levamisole is better tolerated than piperazine citrate and is virtually free of toxic effects. 相似文献
147.
Kevin D Murray Jasmine K Janes Ashley Jones Helen M Bothwell Rose L Andrew Justin O Borevitz 《Molecular ecology》2019,28(24):5232-5247
Spatial genetic patterns are influenced by numerous factors, and they can vary even among coexisting, closely related species due to differences in dispersal and selection. Eucalyptus (L'Héritier 1789; the “eucalypts”) are foundation tree species that provide essential habitat and modulate ecosystem services throughout Australia. Here we present a study of landscape genomic variation in two woodland eucalypt species, using whole‐genome sequencing of 388 individuals of Eucalyptus albens and Eucalyptus sideroxylon. We found exceptionally high genetic diversity (π ≈ 0.05) and low genome‐wide, interspecific differentiation (FST = 0.15) and intraspecific differentiation between localities (FST ≈ 0.01–0.02). We found no support for strong, discrete population structure, but found substantial support for isolation by geographic distance (IBD) in both species. Using generalized dissimilarity modelling, we identified additional isolation by environment (IBE). Eucalyptus albens showed moderate IBD, and environmental variables have a small but significant amount of additional predictive power (i.e. IBE). Eucalyptus sideroxylon showed much stronger IBD and moderate IBE. These results highlight the vast adaptive potential of these species and set the stage for testing evolutionary hypotheses of interspecific adaptive differentiation across environments. 相似文献
148.
149.
Malignant mesothelioma is an aggressive cancer of the pleura that is causally related to exposure to asbestos fibres. The kallikrein serine proteases [tissue (hK1) and plasma (hKB1) kallikreins, and kallikrein-related peptidases (KRP/hK2-15)] and the mitogenic kinin peptides may have a role in tumourigenesis. However, it is not known whether hK1, hKB1, KRP/hK proteins or kinin receptors are expressed in pleural mesotheliomas. The expression of hK1, hKB1, KRP/hK2, 5, 6, 7, 8 and 9, and kinin B(1) and B(2) receptors was assessed in archived selected normal tissue and mesothelioma tumour sections by immunoperoxidase and immunofluorescence labelling. hK1, hKB1 and kinin B(1) and B(2) receptors were expressed in malignant cells of the epithelioid and sarcomatoid components of biphasic mesothelioma tumour cells. The percentage of cells with cytoplasmic and nuclear labelling and the intensity of labelling were similar for hK1, hKB1 and the kinin receptors. KRP/hK2, 6, 8 and 9 were also expressed in the cytoplasm and nuclei of mesothelioma cells, whereas KRP/hK5 and hK7 showed predominantly cytoplasmic localisation. This is a first report, but further studies are required to determine whether these proteins have a functional role in the pathogenesis of mesothelioma and/or may be potential biomarkers for pleural mesothelioma. 相似文献
150.
Chandran Ramakrishna Adrianna Ferraioli Aleth Calle Thanh K. Nguyen Harry Openshaw Patric S. Lundberg Patrick Lomonte Edouard M. Cantin 《PLoS pathogens》2015,11(3)
The establishment of latent infections in sensory neurons is a remarkably effective immune evasion strategy that accounts for the widespread dissemination of life long Herpes Simplex Virus type 1 (HSV1) infections in humans. Periodic reactivation of latent virus results in asymptomatic shedding and transmission of HSV1 or recurrent disease that is usually mild but can be severe. An in-depth understanding of the mechanisms regulating the maintenance of latency and reactivation are essential for developing new approaches to block reactivation. However, the lack of a reliable mouse model that supports efficient in vivo reactivation (IVR) resulting in production of infectious HSV1 and/or disease has hampered progress. Since HSV1 reactivation is enhanced in immunosuppressed hosts, we exploited the antiviral and immunomodulatory activities of IVIG (intravenous immunoglobulins) to promote survival of latently infected immunodeficient Rag mice. Latently infected Rag mice derived by high dose (HD), but not low dose (LD), HSV1 inoculation exhibited spontaneous reactivation. Following hyperthermia stress (HS), the majority of HD inoculated mice developed HSV1 encephalitis (HSE) rapidly and synchronously, whereas for LD inoculated mice reactivated HSV1 persisted only transiently in trigeminal ganglia (Tg). T cells, but not B cells, were required to suppress spontaneous reactivation in HD inoculated latently infected mice. Transfer of HSV1 memory but not OVA specific or naïve T cells prior to HS blocked IVR, revealing the utility of this powerful Rag latency model for studying immune mechanisms involved in control of reactivation. Crossing Rag mice to various knockout strains and infecting them with wild type or mutant HSV1 strains is expected to provide novel insights into the role of specific cellular and viral genes in reactivation, thereby facilitating identification of new targets with the potential to block reactivation. 相似文献