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排序方式: 共有701条查询结果,搜索用时 31 毫秒
31.
Riyaz Bhikoo MBChB Rachael L Niederer PhD MBChB Richard Hart FRANZCO Trevor Sherwin PhD Charles NJ McGhee PhD FRCS FRANZCO 《Clinical & experimental optometry》2013,96(4):430-432
We describe the corneal microstructural changes in a patient with spheroidal degeneration using in vivo confocal microscopy. Multiple hypo‐ and hyper‐reflective spherical lesions were observed in the anterior corneal stroma and Bowman's layer ranging from 45 to 220 μm in size. The corneal epithelium, posterior stroma and endothelium were otherwise unaffected. In vivo confocal microscopy demonstrates good correlation with excised histological samples in climatic droplet keratopathy. It provides a non‐invasive technique to examine the living cornea for degenerative disease and acts as a bridge between clinical and laboratory observations. 相似文献
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33.
Neuropeptide Y Attenuates Stress‐Induced Bone Loss Through Suppression of Noradrenaline Circuits 下载免费PDF全文
PA Baldock S Lin L Zhang T Karl Y Shi F Driessler A Zengin B Hörmer NJ Lee IPL Wong EJD Lin RF Enriquez B Stehrer MJ During E Yulyaningsih S Zolotukhin ST Ruohonen E Savontaus A Sainsbury H Herzog 《Journal of bone and mineral research》2014,29(10):2238-2249
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research. 相似文献
34.
35.
Helen L. Gibson Jeffrey E. Tucker David C. Kaslow Antoniana U. Krettli William E. Collins Michael C. Kiefer Ian C. Bathurst Philip J. Barr 《Molecular and biochemical parasitology》1992,50(2):325-333
Molecular cloning and structure analysis of the gene encoding the Pv200 protein of the Sal-1 strain of Plasmodium vivax revealed an overall identity of 34–37% when the deduced amino acid sequence was compared with the sequences of various major merozoite surface antigens of Plasmodium falciparum, Plasmodium yoelii and Plasmodium chabaudi. When the Sal-1 Pv200 sequence was compared with the corresponding sequence from the Belèm strain of P. vivax, it was found that the two merozoite surface antigens were relatively well conserved with an overall amino acid sequence identity of 81%. A region of 23 repeated glutamine residues, found in the sequence of the Belèm isolate was not found, however, in the Sal-1 sequence. Amino-and carboxy-terminal domains of the Pv200 protein were expressed in the yeast Saccharomyces cerevisiae. Each recombinant protein was shown to react with antibodies in sera from splenectomized Bolivian Saimiri monkeys that had been infected previously with P. vivax, and in human sera from individuals with a history of exposure to vivax malaria. The availability of recombinant DNA-derived Pv200 proteins will now allow a full assessment of their utility in the diagnosis and immunoprophylaxis of the benign tertian malaria associated with P. vivax infection. 相似文献
36.
Dorak MT Shao W Machulla HK Lobashevsky ES Tang J Park MH Kaslow RA 《Genes and immunity》2006,7(6):450-467
Since the complete sequencing of a human major histocompatibility complex (MHC) haplotype, interest in non-human leucocyte antigen (HLA) genes encoded in the MHC has been growing. Non-HLA genes, which outnumber the HLA genes, may contribute to or account for HLA and disease associations. Most information on non-HLA genes has been obtained in separate studies of individual loci. To comprehensively address polymorphisms of relevant non-HLA genes in 'conserved extended haplotypes' (CEH), we investigated 101 International Histocompatibility Workshop reference cell lines and nine additional anonymous samples representing all 37 unambiguously characterized CEHs at MICA, NFKBIL1, LTA, NCR3, AIF1, HSPA1A, HSPA1B, BF, NOTCH4 and a single nucleotide polymorphism (SNP) at HLA-DQA1 as well as MICA, NOTCH4, HSPA1B and all five tumour necrosis factor short tandem repeat (STR) polymorphisms. This work (1) provides an extensive catalogue of MHC polymorphisms in all CEHs, (2) unravels interrelationships between HLA and non-HLA haplotypical lineages, (3) resolves reported typing ambiguities and (4) describes haplospecific markers for a number of CEHs. Analysis also identified a DQA1 SNP and segments containing MHC class III polymorphisms that corresponded with class II (DRB3 and DRB4) lineages. These results portray the MHC where lineages containing non-HLA and HLA variants in linkage disequilibrium may operate in concert and can guide more thorough design and interpretation of HLA-disease relationships. 相似文献
37.
Sequences from higher primates orthologous to the human Xp/Yp telomere junction region reveal gross rearrangements and high levels of divergence 总被引:2,自引:2,他引:2
A high level of sequence polymorphism combined with linkage disequilibrium
has created a limited number of highly diverged haplotypes across the human
Xp/Yp telomere junction region. To gain insight into the unusual genetic
characteristics of this region, we have examined the orthologous sequences
in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla)
and the orang-utan (Pongo pygmaeus). Divergence from the human Xp/Yp
sequence is higher (average 2.6-fold) than that observed at other loci. The
position of the human Xp/Yp telomere is unique, as additional sequences are
present at this location in the other three species. These included an
array of subterminal satellite in the chimpanzee and, in the gorilla a
small interstitial array of telomere-like repeats followed by sequences
with strong homology to the human 18p subterminal region. In the
orang-utan, two alleles with different structures were identified. These
differ by the presence or absence of a short interspersed nuclear element
(SINE) sequence just proximal to long arrays of telomere-like repeat
sequences that probably represent the proximal end of the orang-utan Xp/Yp
telomere. In addition, a high level of sequence divergence between the two
orang-utan structures was identified. This divergence is similar to that
observed between the human Xp/Yp telomere-adjacent haplotypes. The high
sequence divergence and evidence of gross rearrangements indicate that the
Xp/Yp telomeric region has evolved faster than the rest of the genome.
相似文献
38.
Liu C Carrington M Kaslow RA Gao X Rinaldo CR Jacobson LP Margolick JB Phair J O'Brien SJ Detels R 《Journal of acquired immune deficiency syndromes (1999)》2004,37(2):1313-1317
HLA class II alleles were molecularly typed for 100 high-risk seronegative men and 184 low-risk seroconverters from the Multicenter AIDS Cohort Study (MACS). Seven resistant individuals homozygous for CCR5 Delta32 deletions were excluded from analysis. In the univariate analysis, no significant HLA class II associations with resistance/susceptibility to HIV type 1 infection were identified. However, the transporter associated with antigen presentation 2 (TAP2) Ala 665 variant associated with resistance in earlier analyses in the MACS was in linkage disequilibrium with some HLA class II alleles. After adjusting for the established associations with HLA-A*0205 subgroup and TAP2 Ala 665 variant, no HLA class II alleles were independently associated with resistance/susceptibility to HIV-1 infection. Other genetic factors in the HLA class II-TAP region of the major histocompatibility complex might be involved. 相似文献
39.
TEELUCKSINGH S; STEER CR; THOMPSON CJ; SECKL JR; DOUGLAS NJ; EDWARDS CRW 《QJM : monthly journal of the Association of Physicians》1991,78(2):185-190
We describe a young man who developed extensive hypothalamicdysfunction including diabetes insipidus, adipsia, hyperprolactinaemia,and poikiliothermia together with central sleep apnoea followingexposure to toluene. 相似文献
40.
Anju Bansal Jonathan Carlson Jiyu Yan Olusimidele T. Akinsiku Malinda Schaefer Steffanie Sabbaj Anne Bet David N. Levy Sonya Heath Jianming Tang Richard A. Kaslow Bruce D. Walker Thumbi Ndung’u Philip J. Goulder David Heckerman Eric Hunter Paul A. Goepfert 《The Journal of experimental medicine》2010,207(1):51-59