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371.
Summary The filamentous fungus C. lunatus converts progesterone mainly to its 11-hydroxy derivative. C. lunatus transformed with the plasmid pAN 7-1, which contains the E. coli hph gene expressed under the control of the A. nidulans gpd and trpC expression signals, lacks this activity, but exhibits acetyl side chain degradation of progesterone through the reaction scheme progesterone20-hydroxy-progesterone
4-androstene-3,17-dione testolactone+testosterone. The main partof this metabolic pathway is not expressed in the non-transformed strain. It was determined that the site-specific integration of the plasmid into the genome directly influences the expression of genes involved in the bioconversion of steroids. 相似文献
372.
373.
Radovan Turyna David Kachlik Eduard Kucera Petr Kujal Jaroslav Feyereisl Vaclav Baca 《Journal of anatomy》2013,223(1):69-73
The purpose of this study was to describe the distribution and structure of ventral tributaries leading into the inferior vena cava where right-sided paraaortic lymphadenectomy is performed. The study examined 21 retroperitoneal specimens by graphic reconstruction, statistical evaluation, and histological examination of ventral tributaries (VTs). Seventy VTs were identified. The average number per specimen was 3.33. There were 20, 40, and 40% of VTs found in Levels I, II, and III, respectively. During the preparation, we observed an unusual arrangement of the IVC wall, into which VTs were led through a preformed sleeve-like channel and anchored near the lumen. This finding is a key mechanism that explains the ease with which VTs are extracted during surgery. Knowledge of the distribution and histological structure of VTs allows proper orientation of the retroperitoneal area of the front wall of inferior vena cava, which is essential for uncomplicated right-sided paraaortic lymphadenectomy. The histological structure of the VT ostium within the wall of the inferior vena cava explains why injury is easy during the procedure. 相似文献
374.
Marija Rogar Robert Juvan Petra Hudler Radovan Komel 《Environmental and molecular mutagenesis》2017,58(9):701-711
Background: Single nucleotide polymorphisms (SNPs) in mitotic checkpoint genes could confer increased susceptibility to gastric cancer (GC). We investigated the association of Aurora kinase A (AURKA), Aurora kinase B (AURKB), Aurora kinase C (AURKC), Polo‐like kinase 1 (PLK1) and Budding uninhibited by benzimidazol 3, yeast (BUB3) gene polymorphisms with GC risk. Materials and methods: Genotyping of 6 SNPs in AURKA (rs911160 and rs8173), AURKB (rs2289590), AURKC (rs11084490), PLK1 (rs42873), and BUB3 (rs7897156) was performed using TaqMan genotyping assays. Results: Our study demonstrated that rs911160 (AURKA) heterozygous genotype was associated with an increased GC risk (OR = 1.50, 95% CI = 1.01‐2.22, P = 0.043). Analysis of rs911160 (AURKA) showed significant association with an increased risk for intestinal type GC (OR = 1.80, 95%CI = 1.01–3.21, P = 0.040) and the risk was significantly higher in women than men (OR = 2.65, 95%CI = 1.02–6.87, P = 0.033). SNP rs2289590 in AURKB might contribute to susceptibility for the development of gastric cancer, particularly in women (OR = 2.08, 95% CI = 1.05–4.09, P = 0.032). Conclusion: Our findings suggested that AURKA (rs911160) and AURKB (rs2289590) polymorphisms could affect GC risk. Further validation studies in larger and multi‐ethnical populations are needed to elucidate their functional impact on the development of GC. Environ. Mol. Mutagen. 58:701–711, 2017. © 2017 Wiley Periodicals, Inc. 相似文献
375.
Sandhya Xavier Radovan Vasko Kei Matsumoto Joseph A. Zullo Robert Chen Julien Maizel Praveen N. Chander Michael S. Goligorsky 《Journal of the American Society of Nephrology : JASN》2015,26(4):817-829
Excessive TGF-β signaling in epithelial cells, pericytes, or fibroblasts has been implicated in CKD. This list has recently been joined by endothelial cells (ECs) undergoing mesenchymal transition. Although several studies focused on the effects of ablating epithelial or fibroblast TGF-β signaling on development of fibrosis, there is a lack of information on ablating TGF-β signaling in the endothelium because this ablation causes embryonic lethality. We generated endothelium-specific heterozygous TGF-β receptor knockout (TβRIIendo+/−) mice to explore whether curtailed TGF-β signaling significantly modifies nephrosclerosis. These mice developed normally, but showed enhanced angiogenic potential compared with TβRIIendo+/+ mice under basal conditions. After induction of folic acid nephropathy or unilateral ureteral obstruction, TβRIIendo+/− mice exhibited less tubulointerstitial fibrosis, enhanced preservation of renal microvasculature, improvement in renal blood flow, and less tissue hypoxia than TβRIIendo+/+ counterparts. In addition, partial deletion of TβRII in the endothelium reduced endothelial-to-mesenchymal transition (EndoMT). TGF-β–induced canonical Smad2 signaling was reduced in TβRII+/− ECs; however, activin receptor-like kinase 1 (ALK1)–mediated Smad1/5 phosphorylation in TβRII+/− ECs remained unaffected. Furthermore, the S-endoglin/L-endoglin mRNA expression ratio was significantly lower in TβRII+/− ECs compared with TβRII+/+ ECs. These observations support the hypothesis that EndoMT contributes to renal fibrosis and curtailing endothelial TGF-β signals favors Smad1/5 proangiogenic programs and dictates increased angiogenic responses. Our data implicate endothelial TGF-β signaling and EndoMT in regulating angiogenic and fibrotic responses to injury. 相似文献
376.
Osteoarthritis (OA), the most common chronic musculoskeletal disease, represents a leading cause of disability in the elderly population worldwide. At present, there is no aetiological treatment for OA patients. Also, current therapeutic regimens for OA are only partially effective, and that is the main reason for most physicians' complaints. Therefore, one of the biggest challenges in the future will be to find the most appropriate therapy or therapies for OA. Currently, there are three basic modalities of treatment: nonpharmacological, pharmacological and surgical. Regarding pharmacological treatment, numerous molecular pathways involved in the pathophysiology of OA have been investigated as potential therapeutic targets. In preclinical and clinical trials, many compounds and agents have been tested, and some of them have already shown positive effects on the progression of knee and/or hip OA. One such possible pharmacological treatment of OA is anticytokine therapy. Interleukin-1 (IL-1), as a main inflammatory and catabolic cytokine in the pathophysiology of OA, represents one of the possible treatment targets. For specific inhibition of IL-1 production or activity, various treatment strategies could be used. These include the inhibition or modification of IL-1 action through the application of IL-1 receptor antagonist proteins, soluble IL-1 receptors, monoclonal antibodies against IL-1 or against IL-1 receptor I, blocking the formation of active IL-1β, blocking the IL-1 cellular signalling pathways, or using gene therapy. All the above mentioned treatment strategies for specific inhibition of IL-1 production or activity have been investigated in numerous preclinical and clinical studies. Some of these investigations led to the discovery of new potential drugs for the treatment of OA. However, the results of treatment with these drugs were not entirely satisfactory, and further research is required to achieve the desired goals of therapy. 相似文献