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971.
972.

Background

Minimizing warm ischemic (WI) injury is one technical focus of partial nephrectomy (PN). Inducing regional ischemia in the tumor area by clamping segmental renal arteries has become an alternative method to decrease WI injury.

Objective

To study the technical feasibility of precise segmental artery clamping under the guidance of dual-source computed tomography (DSCT) angiography during laparoscopic partial nephrectomy (LPN) and to analyze the factors affecting surgical outcomes.

Design, setting, and participants

Retrospective analysis of 125 patients with unilateral kidney tumor treated from December 2009 to November 2011 with a mean follow-up of 18 mo.

Intervention

All patients received retroperitoneal LPN with the feeding segmental arteries precisely clamped. Most of the target branches were dissected close to the hilar parenchyma. The tumor was excised after precise clamping and renorrhaphy was performed.

Outcome measurements and statistical analysis

Univariable and multivariable logistic regression analyses were performed for categorical variables, and continuous variables were analyzed by linear regression.

Results and limitations

The target branches were isolated and clamped successfully in all patients without clamping the main renal artery. Median estimated blood loss (EBL) was 200 ml, and nine patients received blood transfusion. The accuracy of feeding artery orientation by DSCT angiography reached 93.6%. Tumor size, location, and growth pattern independently influenced the number of clamped branches. The number of clamped branches was significantly associated with postoperative renal function and EBL. Limitations of this study include its retrospective nature and that data are from a single-surgeon series.

Conclusions

The precise segmental artery clamping technique under the guidance of DSCT angiography is feasible and efficient to excise the tumor and to protect the normal parenchyma. The number of clamped branches is associated with tumor characteristics and can predict EBL and loss of renal function.  相似文献   
973.
Zhang K  Lv Z  Jia X  Huang D 《Andrologia》2012,44(4):230-236
The damaging effect of hyperlipidaemia on testicular structure was determined, and the influence of melatonin was evaluated in testicular damage related to hyperlipidaemia. Hyperlipidaemia was induced in ApoE-knockout C57BL/6J male mice fed with high-fat diet alone (group A), or with high-fat diet and melatonin (group B). Six ApoE wild-type C57BL/6J male mice were fed with normal diet, served as controls. At the end of the experimental period, ultrastructural observations showed dramatically histopathological alterations in testicular tissues of group A. The basement membranes of seminiferous tubules were partially thickened and wavy-like in testes of mice with hyperlipidaemia, and vacuolar degeneration of mitochondria and dilation of endoplasmic reticulum were identified as well as the number of mitochondria and lipid droplets decreased significantly in Leydig cells and Sertoli cells. Electrondense deposits were observed in cytoplasms of germ cells. The testicular histostructure in group B treated with melatonin was similar to that of control. Apoptosis was determined by terminal-deoxynucleotidyl-transferase-mediated dUTP nick end labelling. Apoptotic germ cells were significantly more numerous in group A than in group B and controls. The results suggest that melatonin may be potential to attenuate testicular damage by improving histopathological changes and reducing germ cell apoptosis in hyperlipidaemic mice.  相似文献   
974.
The present study aims to define the trend of time related changes with local bacterial alteration of bacterial resistance in severe burns in our burn center during a 12-year period. Retrospective analysis of microbiological results on severely burned wounds between 1998 and 2009 was carried out. A study of 3615 microbial isolates was performed. Staphylococcus aureus was the most commonly isolated pathogen (38.2%) followed by A. baumannii (16.2%), Streptococcus viridans (11.4%), Pseudomonas aeruginosa (10.4%), coagulase-negative staphylococci (CNS, 9.2%). The species ratios of S. aureus and A. baumannii increased significantly from 1st to 8th week of hospitalization, while those of Streptococcus viridans, P. aeruginosa and coagulase-negative staphylococci decreased during the same period. Bacterial resistance rates were compared between the periods 1998-2003 and 2004-2009. Vancomycin remained as the most sensitive antibiotic in S. aureus including methicillin-resistant S. aureus (MRSA). It was very likely that the majority of infections caused by Streptococcus viridans, P. aeruginosa and coagulase-negative staphylococci occurred in the early stage of burn course and the majority of infections caused by A. baumannii occurred 4 weeks after admission. The use of different antibiotics was probably the major contributor to these trends.  相似文献   
975.
976.
Promoter hypermethylation can lead to a loss of genetic imprinting in carcinogenesis. The mechanism for the loss of expression of the imprinted gene TSSC3 has not been investigated in cases of osteosarcoma. In this study, we treated osteosarcoma cell lines with 5-Aza-CdR, which is a widely-used DNA methyltransferase inhibitor, and found dose-dependent reduction in cell growth, conversion of cell morphology to a non-motile phenotype, and obvious increase in apoptosis. In addition, we also found that 5-Aza-CdR reactivated TSSC3 expression through demethylation of the promoter regions. These findings indicate that the TSSC3 gene is silenced through hypermethylation of the promoter regions, a mechanism commonly associated with gene silencing in cancer. Finally, we examined the role of TSSC3 in human osteosarcoma SaOS2 cells. We showed that TSSC3 overexpression suppressed SaOS2 cell growth and increased apoptosis through caspase-3 upregulation, thereby, suggesting that TSSC3 may play a pro-apoptosis role to maintain the normal balance of growth. Taken together, these observations suggest that the epigenetic regulation of TSSC3, a pro-apoptosis gene, provides valuable insights into possible osteosarcoma therapies.  相似文献   
977.
ObjectivesTo summarize and differentiate abdominal ultrasound findings of necrotizing enterocolitis and food protein-induced enterocolitis syndrome.MethodsFrom January 2017 to December 2018, the abdominal ultrasound results of 304 cases diagnosed necrotizing enterocolitis or food protein-induced enterocolitis syndrome were retrospectively analyzed. The presence of pneumatosis intestinalis, portal venous gas, bowel wall thickening, intestinal motility, focal fluid collections and hypoechoic change of gallbladder wall were calculated, and the results were compared and analyzed.ResultsPneumatosis intestinalis, portal venous gas, bowel wall thickening, intestinal motility weakened/absent, focal fluid collections and hypoechoic change of gallbladder wall can be found in both necrotizing enterocolitis and food protein-induced enterocolitis syndrome infants. However, in infants with necrotizing enterocolitis, intestinal motility was weakened/absent in whole abdomen, and in food protein-induced enterocolitis syndrome, it only involved isolated segment of bowel. The positive rates of above signs in necrotizing enterocolitis infants were significantly higher than those in food protein-induced enterocolitis syndrome (p < 0.01). Moreover, it was observed that the rate of weakened intestinal motility besides the lesion segment of bowel in necrotizing enterocolitis infants was 100%, and in food protein-induced enterocolitis syndrome infants, it was 0%, which is supposed to be a main sign for identification.ConclusionIn the early stage, abdominal ultrasound can be used to differentiate necrotizing enterocolitis and food protein-induced enterocolitis syndrome.  相似文献   
978.
目的探讨miR-122-5p对创伤性脑外伤后小胶质细胞凋亡、极化和炎症反应的影响。方法建立创伤性脑外伤(traumatic brain injury,TBI)小鼠模型和细胞模型。使用TBI小鼠脑匀浆刺激星型胶质细胞产生外泌体,microRNA微阵列分析外泌体中显著改变的microRNA。实时荧光定量PCR检测TBI小鼠模型和TBI细胞模型中miR-122-5p表达。使用TUNEL凋亡染色、免疫荧光共聚焦、蛋白质印迹研究miR-122-5p抑制剂在TBI神经炎症中对小胶质细胞凋亡、小胶质细胞M1/M2表型转化、NLRP3通路及NFκB磷酸化的作用。结果通过microRNA微阵列分析发现有83个下调miRNA(改变2倍以上,P<0.05),其中miR-122-5p显著下调(P<0.01),miR-122-5p在TBI小鼠及细胞模型中表达显著下降[(1.0±0.00)vs.(0.41±0.15),P<0.001];[(1.0±0.00)vs.(0.34±0.07),P<0.001]。TUNEL凋亡检测、免疫荧光染色结果表明抑制miR-122-5p表达,可以显著减轻LPS诱导的小胶质细胞凋亡[(8.03±1.30)vs.(3.17±0.34),P<0.001],促进小胶质细胞M1向M2表型转化,即M1表型极化减少[(56.96±13.70)vs.(34.70±3.47),P=0.002],M2表型极化增加[(30.46±3.67)vs.(40.74±2.49),P=0.005]。蛋白质印迹结果表明miR-122-5p抑制剂降低NLRP3炎症小体活化[(0.77±0.10)vs.(0.51±0.11),P=0.02],降低NFκB的磷酸化[(0.73±0.08)vs.(0.50±0.07),P=0.003]。结论miR-122-5p在TBI星形胶质细胞分泌的外泌体及小胶质细胞中表达下调,miR-122-5p抑制剂可以通过抑制TBI后NLRP3炎症小体通路的活化及NFκB的磷酸化,促进小胶质细胞M1向M2表型转化,减少小胶质细胞凋亡,从而减轻TBI后小胶质细胞炎症损伤。  相似文献   
979.
The International Journal of Cardiovascular Imaging - Undiagnosed atrial fibrillation (AF) is one of the main sources of cryptogenic stroke. And strain indices measured by speckle-tracking...  相似文献   
980.
Quantification of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) and their change model during treatment are emerging as a useful tool for assessing the outcome of hepatitis B virus (HBV) infection and predicting the efficacy of antiviral therapy. The aim of this study was to compare the performance of the Elecsys and Architect assays for HBsAg and HBeAg quantification. Quantification of HBsAg and HBeAg, determined by these two assays, were assessed in 1292 sera from patients with chronic hepatitis B(CHB). HBeAg quantification in serum was performed by calibrating the results through HBeAg Paul‐Ehrlich international (PEI) reference standard. The HBV genotype was determined by direct sequencing and phylogenetic analysis. Of 1292 samples, the distribution of genotype was 514 (39.78%) genotype B, 776 (60.06%) genotype C, 2 (0.16%) genotype D. The results of HBsAg and HBeAg quantification between the Architect and Elecsys assays were significantly correlated (HBsAg: r = 0.939; HBeAg: r = 0.987), independent of HBV genotype and treatment phase. The mean differences between the two methods (the log10 [Elecsys] ‐ the log10 [Architect]) were 0.075 log10 IU/mL and ?0.149 log10PE IU/mL in quantifying HBsAg and HBeAg, respectively. This study demonstrates a high correlation between the Elecsys and the Architect assays in quantifying HBsAg and HBeAg, regardless of HBV genotype. Both the two assays can be used to monitor the HBsAg and HBeAg levels in patients with chronic hepatitis B.  相似文献   
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