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991.

Background

Exosomes secreted by tumor cells contain specific antigens that may have immunotherapeutic purposes. The aim of this study was to characterize the proteomic content of lymphoma cell-derived exosomes (LCEXs).

Methods

In this study, exosomes derived from Raji cells (EXORaji) were purified and proteins of EXORaji were separated by one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Protein bands were identified by mass spectrometry. The protein components of EXORaji were analyzed using shotgun technology, and the function proteins of EXORaji were defined and described using the Gene Ontology (GO) database and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis.

Results

A total of 197 proteins were identified in EXORaji; 139 proteins were also identified in Raji cells, showing an overlap of 70.56% of the total proteins in EXORaji. Interestingly, the remaining 58 proteins were unique to EXORaji. The GO database and KEGG were used to define and describe the function of proteins. The data showed that some important proteins involved in antigen procession and presentation as well as cell migration and adhesion were also identified in EXORaji, such as MHC-I and II, HSC70, HSP90, and ICMA-1.

Conclusions

LCEXs express a discrete set of proteins involved in antigen presentation and cell migration and adhesion, suggesting that LCEXs play an important role in the regulation of immunity and interaction between lymphoma cells and their microenvironment. LCEXs harbor most of the proteins of lymphoma cells and could be one of the sources of lymphoma-associated antigens for immunotherapeutic purposes.  相似文献   
992.
Objective To investigate the effects of physical activity (PA) on dyslipidemia and elevated resting heart rate (RHR) in a large-scale cross-sectional study in China. Methods We recruited community-based individuals who were 40-60 years old using a cluster sampling method. The PA levels of the participants were classified as low, moderate, or high, using the International Physical Activity Questionnaire. Dyslipidemia was defined as the detection of abnormalities in lipid indicators, and 4 lipid parameters were evaluated using fasting blood samples. Multivariate logistic regression analyses were used to evaluate the associations of PA with dyslipidemia and RHR. Results A total of 10,321 participants (38.88% men) were included in this study. The percentages of individuals with high, moderate, and low PA levels were 46.5%, 43.9%, and 9.6%, respectively. In both men and women, high PA provided odds ratios of 0.88 [95% confidence interval (CI): 0.83, 0.94] for dyslipidemia and 0.82 (95% CI: 0.73, 0.92) for elevated RHR, compared to participants with low PA. Conclusion Our data suggested that substantial health benefits (related to dyslipidemia and elevated RHR) occurred at higher intensity PA, with greater energy consumption, in middle-aged Chinese people, and particularly in men.  相似文献   
993.
目的探讨G蛋白偶联受体激酶4(G protein-coupled receptor kinase 4,GRK4)对内皮素B型受体(endothelin receptor B,ETB)的异常调节在原发性高血压中的作用及机制。方法选用12~14周龄,体质量300 g左右的雄性自发性高血压大鼠(spontaneously hypertensive rats,SHRs)及其对照鼠(Wistar-Kyoto,WKY)各10只,通过无创鼠尾测压仪测定血压,采用右肾上腺静脉插管灌注ETB受体特异性激动剂BQ3020后观察尿流速及尿钠排泄率,荧光定量PCR检测大鼠肾脏GRK4 mRNA水平,Western blot测定大鼠肾脏GRK4及ETB受体的蛋白表达差异,免疫共沉淀法检测ETB受体磷酸化情况,在动物水平观察高血压状态下ETB受体的功能情况。结果 ETB受体激动剂BQ3020对WKY大鼠有明显利尿排钠作用,且这种利尿排钠作用可以被ETB受体抑制剂BQ788阻断,但在SHR大鼠BQ3020的利尿排钠作用受损[尿流速:(11.23±2.16)vs(3.49±1.32),P<0.05];尿钠排泄率:[(1 551.43±393.47)vs(601.16±128.15),P<0.05];在SHR大鼠肾皮质GRK4的蛋白水平及mRNA水平均较WKY大鼠高[蛋白:(1.38±0.10)vs(0.85±0.07),P<0.05];mRNA:[(2.23±0.15)vs(0.78±0.16),P<0.05],SHR大鼠ETB受体总蛋白水平与WKY大鼠相比差异无统计学意义(P>0.05),但ETB受体磷酸化水平增高。结论 GRK4可能通过对内皮素B型受体的异常调节,参与了原发性高血压发生与发病。  相似文献   
994.
We investigated the effect of smaller dose, weight-adjusted heparin with earlier monitoring of activated partial thromboplastin time on the incidence of ischemic and hemorrhagic complications in patients with ST-elevation myocardial infarction treated with full-dose tenecteplase. We compared the outcomes of patients enrolled in the Second Assessment of the Safety and Efficacy of a New Thrombolytic Regimen (ASSENT-2; n = 8,461) who received heparin stratified by weight (patients weighing >67 kg received a 5,000-U bolus plus infusion at 1,000 U/hour; those weighing < or =67 kg received a 4,000-U bolus plus infusion at 800 U/hour) with patients in ASSENT-3 who received weight-adjusted heparin (60-U/kg bolus, maximum 4,000 U/hour, followed by a 12-U/kg/hour infusion, maximum 1,000 U/hour). Compared with patients in ASSENT-2, those in ASSENT-3 had similar rates of 30-day mortality, recurrent infarction, and intracranial hemorrhage, less major bleeding (2.2% vs 4.7%, p <0.001), and less refractory ischemia (6.5% vs 8.6%, p <0.001). After adjustment for baseline characteristics, patients in ASSENT-3 had similar rates of 30-day mortality (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.77 to 1.19) and intracranial hemorrhage (OR 1.02, 95% CI 0.61 to 1.69) but less major bleeding (OR 0.49, 95% CI 0.35 to 0.67) than did patients in ASSENT-2. These findings support the use of smaller dose, weight-adjusted heparin in patients with ST-elevation myocardial infarction treated with tenecteplase.  相似文献   
995.
Typical Turcot's syndrome is characterized by the association of a brain glioma together with multiple colonic polyposis, in which the number of polypoid lesions is small and the association of colonic cancer occurs at a younger age than in familial adenomatous polyposis. We describe a family in which both the father and his son presented with typical Turcot's syndrome without parental consanguinity. This is the first report of a family that is considered to follow an autosomal dominant inheritance. After reviewing 25 documented cases in which the average age of death was 20.3 years old, it was learned that the major cause of death was brain tumor (76 percent) and the minor cause was colon cancer (16 percent). Patients were very young and, therefore, unlikely to have produced a child before their death. These facts seem to support the theory that Turcot's syndrome is an autosomal dominant disorder.  相似文献   
996.
997.
目的探索螺内酯对门脉高压实验犬和肝硬变患者门脉血流动力学的作用.方法用直接门脉插管测压和99mTcMIBI心肝放射性摄取比值(H/L)测定慢性胆总管结扎肝硬变犬(n=16)门静脉压力和门体分流,口服螺内酯20mg/(kg·d).肝硬变患者14例测定H/L,门静脉内径和流速后口服螺内酯80mg/d,4wk为1疗程.结果完成试验的犬13只治疗前后门脉压力(kPa)从259±051下降为242±047(P<005),H/L从033±006降至030±008(P<005).14例肝硬变患者治疗前后H/L值从120±026降为102±034(P<005),门脉内径(mm)从139±23缩小为123±20(P<005).门静脉流速明显增加.结论螺内酯口服可降低门脉压力和门体分流.  相似文献   
998.
目的观察静脉内皮素双受体拮抗剂RO2610612在急性肺栓塞中的应用效果,研究内皮素与急性肺栓塞的关系。方法12只健康杂种犬随机分为对照组和实验组,每组6只。两组所有动物给予戊巴比妥静脉麻醉后分别于颈静脉插入热稀释漂浮导管连接生理监护仪;气管内插入气管插管连接呼吸描记器。采集栓塞前数据后于颈静脉注射自体血栓建立急性肺栓塞动物模型。实验组建立模型后1h开始持续静滴RO26106120.2mg/(kg.h),对照组同时输入等量生理盐水。对照组及实验组所有动物于栓塞前、栓塞后1,2,4,6h记录体、肺循环血流动力学指标、呼吸生理指标;取股动脉血3ml,采用放射免疫法测定动脉血内皮素-1水平,并测动脉血气。结果两组动物栓塞后较栓塞前血浆内皮素-1水平、肺动脉平均压、肺血管阻力、呼吸频率、动脉血二氧化碳分压和肺气道阻力显著性升高(P<0.05),心输出量、动脉血氧分压和肺动态顺应性显著性下降(P<0.05)。实验组于栓塞2h后肺动脉平均压、肺血管阻力、呼吸频率、肺气道阻力升高水平显著性低于同时期对照组(P<0.05),血浆内皮素-1水平、心输出量、和肺顺应性显著性高于对照组(P<0.05)。结论在急性肺栓塞病理过程中,内皮素参与了肺循环阻力升高与肺气道阻力升高和肺顺应性下降的形成。内皮素受体拮抗剂拮抗内皮素与其受体的结合,在急性肺栓塞中,可以减缓肺循环阻力、肺气道阻力的上升,因而可能成为急性肺栓塞临床治疗的新手段。  相似文献   
999.
Background: Gout is an inflammatory disease in which genetic factors play a role. ABCG2 is a urate transporter, and the Q141K and Q126X variants of ABCG2 have been associated with a risk of developing gout, though previous studies of these associations have been inconsistent. Therefore, we conducted a meta-analysis to explore the relationship between these genetic variants and gout. Methods: We examined 8 electronic literature databases. In total, 9 eligible articles on the associations between the Q141K (rs2231142) and Q126X (rs72552713) variants and gout risk, including 11 case-control studies were selected. We used odds ratios (OR) and 95% confidence intervals (CI) to assess the strength of these relationships in dominant, recessive, and co-dominant models. Results: This study included 6652 participants (2499 gout patients and 4153 controls). The Q141K variant was found to significantly increase the risk of gout in Asians (dominant model: OR=2.64, 95% CI=2.04-3.43, P=0.02 for heterogeneity; recessive model: OR=3.19, 95% CI=2.56-3.97, P=0.28 for heterogeneity; co-dominant model: OR=1.37, 95% CI=1.18-1.59, P=0.09 for heterogeneity) and other populations (dominant model: OR=1.85, 95% CI=1.20-2.85, P<0.0001 for heterogeneity; recessive model: OR=3.78, 95% CI=2.28-6.27, P=0.19 for heterogeneity; co-dominant model: OR=1.48, 95% CI=1.26-1.74, P=0.19 for heterogeneity). The Q126X variant also significantly increased the risk of gout in Asians (dominant model: OR=3.87, 95% CI=2.07-7.24, P=0.06 for heterogeneity). Conclusions: These results suggest associations between the rs2231142 and rs72552713 ABCG2 gene polymorphisms and gout risk, which led to unfavorable outcomes. However, studies with larger sample sizes and homogeneous populations should be performed to confirm these results.  相似文献   
1000.
WISP1, a Wnt-induced secreted protein, has been found to have anticancer activity. ALL is a leading cause of death. Here we investigate the WISP1 effects on ALL Jurkat cells. Cell viability was assessed by CCK-8. Cell cycle and apoptosis were detected by flow cytometry. Mitochondrial membrane potential (MMP) was monitored using TMRM. Generation of reactive oxygen species (ROS) was quantified using DCFH-DA. Western blot was used to detect the expression of cell proliferation and apoptosis related genes. The results showed that knockdown of WISP1 significantly inhibited proliferation of Jurkat cells. Parallelly, cell cycle distribution was increased at G1 phase and apoptotic rate was induced after WISP1 knockdown. Furthermore, knockdown of WISP1 induced apoptosis of Jurkat cells was also associated with loss of MMP and generation of ROS. Western blot results showed that the protein expression p-AKT, PCNA, CDK1, P-ERK, CDK2, VEGF, VEGFR2 and Bcl2 were decreased, while the expression of Bax was up-regulated. In conclusion, WISP1 plays an important role in proliferation and apoptosis of Jurkat cells in mitochondria dependent pathway, the specific mechanisms need further study.  相似文献   
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