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1.
2.
Differential mortality: some comparisons between England and Wales, Finland and France, based on inequality measures 总被引:4,自引:0,他引:4
Inequalities in mortality between social classes or socioeconomic groups were compared in three European countries, using similar sources of data from large national cohort studies. People registered at a census in 1971 (1975 for France) or a sample of them, were followed until 1980 or 1981. The Gini coefficient, a measure widely used in economics, allowed the comparison of various situations involving different numbers and group sizes. It was applied to age groups 35-44, and 45-54 for men only. According to this measure, inequalities were of the same order in England and Wales and Finland, and greater in France. Differences between the three countries concerning the principal causes of death leading to inequalities were cardiovascular diseases in England and Wales, accidents and cardiovascular diseases in Finland, and cancer and cirrhosis in France. 相似文献
3.
A patient with a spontaneously thrombosed arteriovenous malformation (AVM) presented with epilepsy. The CT and MRI appearances were of an intrinsic cerebral neoplasm with extensive surrounding vasogenic cerebral oedema and a mass effect. Histopathology confirmed a large thrombosed AVM. The natural history of AVMs and spontaneous thrombosis are reviewed. 相似文献
4.
Differential expression of extracellular matrix metalloproteinase inducer (CD147) in normal and ulcerated corneas: role in epithelio-stromal interactions and matrix metalloproteinase induction 总被引:12,自引:0,他引:12 下载免费PDF全文
Gabison EE Mourah S Steinfels E Yan L Hoang-Xuan T Watsky MA De Wever B Calvo F Mauviel A Menashi S 《The American journal of pathology》2005,166(1):209-219
Extracellular matrix metalloproteinase inducer (EMMPRIN) was originally identified on the tumor cell surface as an inducer of matrix metalloproteinase (MMP) production in neighboring fibroblasts. Here we demonstrate a role for EMMPRIN in MMP induction during corneal wound healing. MMP and EMMPRIN expression was analyzed in normal and ulcerated human corneas, as well as in corneal epithelial and stromal cells in culture using confocal microscopy, zymography, immunoblots, and real-time polymerase chain reaction. In normal cornea EMMPRIN was predominantly expressed in the epithelium but was markedly induced in the anterior stroma of ulcerated corneas. This coincided with MMP-2 induction that co-localized with EMMPRIN at the epithelio-stromal boundary. The role of epithelial-stromal interaction in MMP induction was investigated in an in vitro co-culture system and demonstrated an induction and co-localization of EMMPRIN and MMP-2 in the fibroblasts at the interface with epithelial cells. Direct contact of fibroblasts with EMMPRIN-containing purified epithelial cell membranes also induced MMP-1, MMP-2, and EMMPRIN and this was inhibited by a blocking anti-EMMPRIN antibody, suggesting that EMMPRIN was primarily responsible for this induction. These findings, and the up-regulation of EMMPRIN by epidermal growth factor and transforming growth factor-beta, demonstrate a role for EMMPRIN in wound healing and suggest that sustained local up-regulation of EMMPRIN and MMPs in chronic situations in which healing is delayed may lead to excessive matrix degradation and corneal melts. 相似文献
5.
Hfq-dependent regulation of OmpA synthesis is mediated by an antisense RNA 总被引:17,自引:1,他引:17 下载免费PDF全文
Udekwu KI Darfeuille F Vogel J Reimegård J Holmqvist E Wagner EG 《Genes & development》2005,19(19):2355-2366
This paper shows that the small RNA MicA (previously SraD) is an antisense regulator of ompA in Escherichia coli. MicA accumulates upon entry into stationary phase and down-regulates the level of ompA mRNA. Regulation of ompA (outer membrane protein A), previously attributed to Hfq/mRNA binding, is lost upon deletion of the micA gene, whereas overexpression of MicA inhibits the synthesis of OmpA. In vitro, MicA binds to the ompA mRNA leader. Enzymatic and chemical probing was used to map the structures of MicA, the ompA mRNA leader, and the complex formed upon binding. MicA binding generates a footprint across the ompA Shine-Dalgarno sequence, consistent with a 12 + 4 base-pair interaction, which is additionally supported by the effect of mutations in vivo and by bioinformatics analysis of enterobacterial micA/ompA homolog sequences. MicA is conserved in many enterobacteria, as is its ompA target site. In vitro toeprinting confirmed that binding of MicA specifically interferes with ribosome binding. We propose that MicA, when present at high levels, blocks ribosome binding at the ompA translation start site, which-in line with previous work-secondarily facilitates RNase E cleavage and subsequent mRNA decay. MicA requires the presence of the Hfq protein, although the mechanistic basis for this remains unclear. 相似文献
6.
Anti-thymosin alpha 1 monoclonal antibodies recognized, on immunoblots, 1 to 2 bands corresponding to molecules of 34 and 35 Kd when using aqueous extracts of thymus, spleen, kidney, liver, brain, pituitary and adrenal glands from rats or mice. Anti-bovine thymopoietin polyclonal antibodies, in the same conditions, labelled analogous 34, 35 and 35.5 Kd molecules in brain and thymus extracts but also a 40 Kd molecules in thymus and a 90 Kd in brain extracts. Anti-synthetic thymulin monoclonal antibodies recognized irregularly and poorly a 52 Kd molecule from thymus and brain extracts. These results suggest that thymopoietin, thymulin and specially Thymosin alpha 1 are first synthesized in large precursors. Finally, other organs seem capable of synthesizing thymosin alpha 1 and probably thymopoietin, but for thymulin, the results are too irregular to conclude. 相似文献
7.
Cloning and expression of surface antigens from occult chronic hepatitis B virus infections and their recognition by commercial detection assays 总被引:6,自引:0,他引:6
Jeantet D Chemin I Mandrand B Tran A Zoulim F Merle P Trepo C Kay A 《Journal of medical virology》2004,73(4):508-515
Occult hepatitis B virus (HBV) infections show little or no serological markers of viral infection, including the absence of hepatitis B surface antigen (HBsAg) which is the main marker of ongoing HBV infection. Such infections can be important in the context of blood and/or organ donations. To study whether mutations contribute to HBsAg seronegativity, S gene sequences from such patients were amplified and cloned. Sequencing revealed 12 clones from seven different patients which contained potentially important mutations. The sequences were subcloned into an expression vector and mutant HBsAgs were expressed in cell culture. The capacity of three HBsAg detection assays to recognise the mutant HBsAgs was studied. Three categories were found: mutant HBsAgs that are not recognised by the assays, those that are recognised as well as wild-type (WT) antigen and an intermediate category where detection of the mutant HBsAgs is reduced with respect to WT. Most of the isolates fall into the second category. Mutations can therefore contribute to HBsAg seronegativity in occult HBV infections, but in most cases the explanation is probably the low level of viral replication. 相似文献
8.
High-intensity intermittent running training improves pulmonary function and alters exercise breathing pattern in children 总被引:2,自引:0,他引:2
Nourry C Deruelle F Guinhouya C Baquet G Fabre C Bart F Berthoin S Mucci P 《European journal of applied physiology》2005,94(4):415-423
We investigated the effects of short duration running training on resting and exercise lung function in healthy prepubescent children. One trained group (TrG) (n = 9; three girls and six boys; age = 9.7 ± 0.9 year) participated in 8 weeks of high-intensity intermittent running training and was compared to a control group (ContG) (n = 9; four girls and five boys; age = 10.3 ± 0.7 year). Before and after the 8-week period, the children performed pulmonary function tests and an incremental exercise test on a cycle ergometer. After the 8-week period, no change was found in pulmonary function in ContG. Conversely, an increase in forced vital capacity (FVC) (+7 ± 4% ; P = 0.026), forced expiratory volume in one second (+11 ± 6% ; P = 0.025), peak expiratory flows (+17 ± 4% ; P = 0.005), maximal expiratory flows at 50% (+16 ± 10% ; P = 0.019) and 75% (+15 ± 8% ; P = 0.006) of FVC were reported in TrG. At peak exercise, TrG displayed higher values of peak oxygen consumption (+15 ± 4% ; P<0.001), minute ventilation (+16 ± 5% ; P = 0.033) and tidal volume (+15 ± 5% ; P = 0.019) after training. At sub-maximal exercise, ventilatory response to exercise
was lower (P = 0.017) in TrG after training, associated with reduced end-tidal partial oxygen pressure (P<0.05) and higher end-tidal partial carbon dioxide pressure (P = 0.026). Lower deadspace volume relative to tidal volume was found at each stage of exercise in TrG after training (P<0.05). Eight weeks of high-intensity intermittent running training enhanced resting pulmonary function and led to deeper exercise ventilation reflecting a better effectiveness in prepubescent children. 相似文献
9.
Genetic variability of hepatitis C virus in chronically infected patients with viral breakthrough during interferon-ribavirin therapy 总被引:4,自引:0,他引:4
Vuillermoz I Khattab E Sablon E Ottevaere I Durantel D Vieux C Trepo C Zoulim F 《Journal of medical virology》2004,74(1):41-53
Little is known about hepatitis C virus (HCV) breakthrough during antiviral therapy, although it would help in understanding HCV resistance to current antiviral treatments. To analyse the implication of virological factors and the vigour of humoral immune responses in this phenomenon, we studied nine chronic hepatitis C patients with a viral breakthrough during IFN/ribavirin combination therapy, as well as five responders and five non-responders. The IRES and regions coding for the capsid protein, the PePHD domain of envelope glycoprotein E2 and the NS5A and 5B proteins were amplified by RT-PCR before treatment, before and during breakthrough, and after treatment. The major variant sequence was obtained by direct sequencing. The heterogeneity of quasispecies was studied by SSCP in all patients and sequencing after cloning in seven genotype 1b-infected patients. Humoral responses against HCV epitopes were also analysed. The major sequences of IRES, PePHD, and NS5B remained stable during treatment, regardless of the treatment response. However, the capsid protein and the regions flanking PePHD showed sequence variations in breakthrough patients, although no specific mutation was identified. The variable V3 region of NS5A, but not the PKR-binding domain and the ISDR, seemed to be associated with differences in response to treatment. The analysis of HCV quasispecies revealed no characteristic pattern during treatment in breakthrough patients, whose HCV genome profiles looked most similar to that of non-responders. The humoral response was similar between groups. In conclusion, viral breakthrough does not seem to be due to selection of resistant strains with signature mutations. 相似文献
10.
Ben Khadhra Hajer Rose-Robert Françoise Herpe Yves Edouard Sevestre Henri Choukroun Gabriel Catherine Luc Amant Carole Saint Fabien 《International urology and nephrology》2021,53(1):59-67
International Urology and Nephrology - Biomarkers for the diagnosis and monitoring treatment response of kidney cancer are urgently needed. Neutrophil gelatinase-associated lipocalin (NGAL) is a... 相似文献