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BACKGROUND: Brainstem gliomas are highly heterogeneous tumors both in their clinical manifestation and in their pathology. Despite significant advances in the surgery for brainstem gliomas many aspects of this pathology are still unelear. OBJECTIVE: To evaluate the clinical, radiological and surgical outcome of 40 focal "intrinsic" brainstem gliomas and propose a surgical strategyoriented classification. MATERIALS AND METHODS: A total of 40 focal ‘intrinsie’ ("expanding variety") tumors have been operated over a period of 8.5-years (January 1998-June 2007). Our criteria included patients with (1) well-defined gadolinium enhancing tumor, (2) relatively long duration of symptoms (〉 six months) and (3) good neurological functional status and independent for all activities of davy living. The cutoff size of 2 cm was not rigidly adhered to. RESULTS: The "intrinsic" brainstem tumors were classified into three types: Expanding, diffuse infiltrative and pure ventral varieties. 相似文献
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Krutchen AE; Bjarnason H; Stackhouse DJ; Nazarian GK; Magney JE; Hunter DW 《Radiology》1996,200(1):159
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G. K. Hulse E. Milne D. R. English C. D. J. Holman 《Addiction (Abingdon, England)》1998,93(10):1553-1558
Aims/Design. Assessment of the association between the regular use of opiates by women during pregnancy and antepartum haemorrhage has been made difficult by the low prevalence of these conditions observed in clinical settings. As a consequence, most published studies lack statistical power due to the small number of cases. We combined all suitable published data in a meta-analysis to assess the association more accurately. Findings. Meta-analysis produced a pooled estimate of the crude odds ratio for antepartum haemorrhage in relation to maternal opiate use of 2.33 (95%CI 1.32-4.30). Conclusions. This odds ratio estimate is consistent with a moderately strong association. Studies included did not adjust for possible confounders (e.g. prenatal care, cocaine or tobacco), so confounding is likely to account for at least some of the observed effect. The relative consistency of results from studies included in the meta-analysis that were conducted in different countries and at different times adds to the strength of the evidence for an association between opiate use and antepartum haemorrhage. Well designed studies are urgently required to assess the independent effects of different types and patterns of maternal opiate use and confounders such as cigarette smoking, illicit cocaine use and antenatal care on antepartum haemorrhage. 相似文献
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The effect of food on the oral bioavailability of sustained-release morphine sulfate tablets (ORAMORPH SR; Roxane Laboratories, Inc., Columbus, OH; OSR) was examined in an open-label, randomized, two-period crossover study. Healthy male volunteers received a 30-mg OSR tablet orally every 12 hours for seven doses during both the fasted and fed states. Dosing periods were separated by a 14-day washout. Volunteers in the fasted group received all doses either 2 hours before or after meals. Volunteers in the fed group received all doses immediately after meals. All meals were standardized. Serial blood samples were collected for analysis of plasma morphine concentration by radioimmunoassay. Pharmacokinetic parameters were calculated using plasma concentration data collected after the last dose at 72 hours of each dosing period. The two one-sided t analysis indicated confidence intervals between 80% and 120% for maximum peak plasma concentration (Cmax), AUC72-84hr, Cavg, and Cmin. The relative bioavailability of OSR administered after meals was 90.2% of that administered in the fasted state. As compared with the fasted condition, morphine bioavailability was essentially unchanged when multiple oral doses of 30-mg OSR tablets were given after meals. 相似文献
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Matthew GK Benesch Rongrong Wu Gopal Menon Kazuaki Takabe 《American journal of cancer research》2022,12(12):5403
Outcomes in pancreatic ductal adenocarcinoma (PDAC) are known to be worse in tumors with high integrin β1 expression, but targeted monotherapy against this integrin has not been effective. Seven other beta integrins are expressed in mammalian biology and they are known to have overlapping and compensatory signaling in biological systems. However, their roles in PDAC are poorly understood and have not been systematically compared to integrin β1 biology. In this study, we analyzed the clinical outcomes against beta integrin 1-8 (ITGB1-8) expression in PDAC samples from two large independent cohorts, The Cancer Genome Atlas (TCGA) and . Biological function and tumor microenvironment composition were studied using Gene Set Enrichment Analysis and xCell. Expression of all eight beta integrins is significantly increased in PDACs relative to normal pancreatic tissues (all P<0.001). ITGB1, 2, 5, and 6 have similarly enriched gene patterns related to transforming growth factor (TGF)-β, epithelial mesenchymal transition, inflammation, stemness, and angiogenesis pathways. Homologous recombination defects and neoantigens are increased in high-ITGB4, 5, and 6 tumors, with decreased overall survival in high-ITGB1, 5, and 6 tumors compared to low expression tumors (hazard ratios 1.5-2.0). High-ITGB1, 2, and 5 tumors have increased fibroblast infiltration (all P<0.01) while endothelial cells are increased in high-ITGB2 and 3 tumors (all P<0.05). Overall, beta integrin expression does not correlate to immune cell populations in PDACs. Therefore, while all beta integrins are overexpressed in PDACs, they exert differential effects on PDAC biology. ITGB2, 5, and 6 have a similar profile to ITGB1, suggesting that future research in PDAC integrin therapy needs to consider the complementary signaling profiles mediated by these integrins. GSE21501相似文献