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981.
982.
983.
984.
NK4基因在人胰腺癌细胞中的表达及其生物学活性   总被引:2,自引:0,他引:2  
目的 肝细胞生长因子通过其受体c met的激活 ,在调节肿瘤侵袭、转移和血管形成中具有重要作用。NK4不仅是肝细胞生长因子的拮抗剂 ,而且也是血管形成的抑制剂 ,阻断HGF/c met途径和肿瘤血管的形成可成为抗胰腺癌治疗的策略之一。为此 ,构建NK4基因真核细胞表达载体并进行转染研究 ,探讨NK4基因在胰腺癌细胞中的表达及其生物学活性。方法 对重组 pcDNA3/hNK4质粒转行酶切 ,将NK4基因克隆到真核表达载体pRC/CMV2 ,应用脂质体将重组 pRC/CMV2 hNK4质粒转入胰腺癌SW 1990细胞中 ,采用逆转录聚合酶链反应 (RT PCR)及免疫印迹 (Westernblot)分别检测转染肿瘤细胞中NK4mRNA和蛋白的表达 ,并筛选出高转录和高表达的细胞克隆。以MTT法检测其细胞克隆表达产物对血管内皮细胞增殖的影响。结果 转导NK4基因的SW1990细胞可表达并分泌NK4,RT PCR扩增出预期的 45 3bp片段 ,Westernblot显示有 5 0 0 0 0的NK4蛋白 ,其上清液可显著抑制血管内皮细胞的生长 (0 .5 37± 0 .10 6和 1.15 2± 0 .12 8,0 .736± 0 .10 8和 1.16 1± 0 .110 ,P <0 .0 1)。结论 NK4基因对血管内皮细胞的生长具有抑制作用 ,在肿瘤基因治疗中可能具有重要意义  相似文献   
985.
BACKGROUND: Several nested case-control studies have reported the potentially causal relationship between Helicobacter pylori infection and the development of gastric cancer. However, there has been no prospective study evaluating this issue. The purpose of this study is to examine the impact of H pylori infection on gastric cancer occurrence in a general Japanese population (Hisayama, Japan) stratified according to sex, using a prospective study design. METHODS: A total of 2602 subjects aged 40 years or older (1070 men; mean age, 57 years; 1532 women; mean age, 59 years) without a history of gastrectomy or gastric cancer were classified according to the status of the serum IgG antibodies to H pylori and observed prospectively for 9 years from 1988. RESULTS: Infection of H pylori was more common in men (71.5%) than in women (62.5%; P<.001). The age-adjusted incidence of gastric cancer for men (5.3 per 1000 person-years) was 4-fold higher than that for women (1.3; P<.001). In men, the age-adjusted incidence of gastric cancer was significantly higher in the subjects with H pylori infection than in those without it (6.2 vs 2.5; relative risk, 2.59 [95% confidence interval, 1.03-6.50]), whereas no significant difference was observed in women (1.2 vs 1.1; relative risk, 0.99 [95% confidence interval, 0.36-2.68]). These results were similar even after controlling for other risk factors in multivariate analysis. It was estimated that 40.1% of gastric cancers for men in this cohort were attributable to H pylori infection. CONCLUSION: A significant relationship exists between infection with H pylori and subsequent occurrence of gastric cancer for men but not for women in this Japanese population.  相似文献   
986.
OBJECTIVES: The study evaluated the transcardiac extraction or spillover of aldosterone (ALDO) in normal subjects and in patients with congestive heart failure (CHF). BACKGROUND: Aldosterone promotes collagen synthesis and structural remodeling of target organs such as the heart. Spironolactone, an ALDO receptor antagonist, has recently been reported to reduce the mortality of patients with CHF; however, the effects of spironolactone on the transcardiac gradient of ALDO have not been clarified. METHODS: We measured plasma ALDO in the aortic root (AO) and coronary sinus (CS) in normal subjects and 113 consecutive CHF patients and also measured plasma procollagen type III aminoterminal peptide (PIIINP) in CS, a biochemical marker of myocardial fibrosis. RESULTS: Plasma ALDO was significantly lower in the CS than in the AO in normal subjects (n = 15; 61.2 +/- 9.3 vs. 83.1 +/- 11.8 pg/ml, p < 0.0001). In 96 CHF patients who did not receive spironolactone, plasma ALDO was significantly lower in the CS than in the AO (59.3 +/- 3.9 vs. 73.8 +/- 4.9 pg/ml, p < 0.0001). In contrast to the difference in these 96 patients, there was no significant difference in ALDO between the AO and CS in 17 patients who received spironolactone (127.4 +/- 20 vs. 124.0 +/- 19 pg/ml, p = 0.50). Stepwise multivariate analyses showed that spironolactone therapy had an independent and significant negative relationship with the transcardiac gradient of plasma ALDO in patients with CHF. In addition, significant positive correlations were seen between the transcardiac gradient of plasma ALDO and PIIINP (r = 0.565, p < 0.0001) and the left ventricular end-diastolic volume index (r = 0.484, p < 0.0001). CONCLUSIONS: These results indicate that plasma ALDO is extracted through the heart in normal subjects and in CHF patients who do not receive spironolactone and that spironolactone inhibits the transcardiac extraction of ALDO in CHF patients, suggesting that spironolactone blocks the effects of ALDO on the failing heart in patients with CHF.  相似文献   
987.
988.
Distribution of galanin-like peptide in the rat brain   总被引:4,自引:0,他引:4  
Galanin-like peptide (GALP) is a novel galanin-like peptide isolated from the porcine hypothalamus. To determine the distribution of GALP in the rat brain, we performed immunohistochemical studies using a monoclonal antibody toward the N-terminal sequence of GALP. GALP-immunoreactive neuronal cell bodies were observed only in the arcuate nucleus (Arc), which was further confirmed by in situ hybridization studies using digoxigenin-labeled antisense GALP riboprobe. Additional immunostained cells were found in the median eminence and infundibular stalk. The GALP neurons found in the Arc were further characterized by double label immunohistochemistry. More than 85% of the GALP neurons were immunostained with leptin receptor antibody. However, the GALP neurons and fibers found in the Arc were not labeled with alpha-MSH, somatostatin, neuropeptide Y, agouti-related protein, or galanin antibodies, indicating that GALP is found in neurons other than these known Arc neurons. Dense staining of GALP-containing fibers was found in the anterior parvicellular part of the paraventricular hypothalamic nucleus, in the ventral part of the lateral septal nucleus, and in the bed nucleus of the stria terminalis. Relatively dense staining was noted in the medial preoptic area (MPA), and weak staining was noted in the periventricular hypothalamic nucleus. Detailed double labeling studies in the paraventricular hypothalamic nucleus demonstrated that GALP-containing fibers converged in a more rostral direction than did agouti-related protein-containing fibers. Furthermore, GALP-immunoreactive fibers were in close apposition with GnRH-immunoreactive fibers in the MPA and bed nucleus of the stria terminalis, and about 6% of GnRH-positive neurons in the MPA showed close contact with the GALP-immunoreactive fibers. Our findings indicate that GALP neurons, as leptin-responsive neurons, may participate in the regulation of feeding behavior and/or reproductive functions.  相似文献   
989.
Pancreaticobiliary maljunction: etiologic concepts based on radiologic aspects   总被引:15,自引:0,他引:15  
BACKGROUND: The purpose of this study was to develop a new concept of the embryonic etiology of pancreaticobiliary maljunction (PBM) based on cholangiopancreatograms. METHODS: The subjects were 202 patients with PBM (60 men and 142 women) in whom the junction of the pancreatic and bile ducts was radiologically diagnosed as being located outside of the duodenal wall; 133 of the 202 patients also had congenital cystic dilatation of the bile duct (CCBD). RESULTS: The length of the duct from the junction to the orifice of the major papilla (the common channel) ranged from 0.5 to 5 cm on the cholangiopancreatograms. Small radicles of the pancreatic duct arose from the common channel in 36 of the 202 patients. This finding suggests that the common channel is itself the main pancreatic duct in patients with PBM. Moreover, cholangiopancreatography revealed that in 99 of the 202 patients, there was a narrowed duct segment distal to the biliary cyst in patients with CCBD or distal to the normal bile duct in those without CCBD; the length of the narrowed segment varied. Histologic examination revealed smaller branches that had arisen from this narrowed segment in 2 anatomic specimens. This also suggests that the narrowed ductal segment belongs to the pancreatic duct system. CONCLUSION: PBM is an anomaly that is probably caused by a disturbance in the embryologic connections (misarrangement) of the pancreatic and biliary duct system that occurs extremely early during gestation when the bile duct joins with the ventral pancreatic duct system. PBM is not due to an arrest of the normal migration of the common channel into the duodenal lumen during embryonic development.  相似文献   
990.
We report a case of biliary cystadenocarcinoma of the liver with superficial spread to the extrahepatic bile duct. Preoperative endoscopic retrograde cholangiography revealed communication between a 4.5-cm cyst in segment 4 of the liver and the bile duct. From the findings obtained by peroral cholangioscopy and intraoperative cholangioscopy, the granular mucosa in the bile duct was diagnosed as superficially spreading cancer. The right posterior segmental bile duct and the right anterior segmental bile duct were resected at the point where the spread of cancer was no longer traceable and left lobectomy plus caudate lobectomy was carried out. This achieved radical resection, leaving the resected margin of the bile duct free from cancer. Histopathologically, well-differentiated papillary adenocarcinoma was found on the inner surface of the cyst, and the cancer had superficially spread from the cyst to the extrahepatic bile duct via the 2.5-mm diameter communication between the cyst and bile duct. The cancer was limited only to the mucosal layer all over the lesion. When performing radical surgery for biliary cystadenocarcinoma, it is recommended that cholangioscopy be performed to examine whether the cancer has superficial spread to the extrahepatic bile duct or not. Bile duct resection should be carried out, depending on the extent of the superficial spread, so that the resected margin of the bile duct is free from cancer.  相似文献   
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