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991.
目的探讨V1导联终末电势(PTFV1)在急性心肌梗死(AMI)患者溶栓前后改变及其临床意义。方法将86例AMI入院当天即进行溶栓治疗的患者,根据溶栓后冠脉是否再通分为溶栓再通组(A组)62例,溶栓未通组(B组)24例,并对AMI溶栓前后的PTFV1值进行动态观察,及溶栓后两组左室射血分数(LVEF)进行对比分析。结果A组PTFV1异常检出率与入院时比有非常显著性差异(P<0.01),而B组则无显著差异(P>0.05),LVEF值B组比A组显著下降(P<0.01)。结论AMI溶栓并使冠脉再通的患者,可使PTFV1负值在溶栓后得到减小,并改善左心功能,减小住院死亡率,对评价AMI近斯预后有明显的意义。  相似文献   
992.
993.
目的 研究高血压脑出血患者血肿周围脑组织细胞色素C的释放规律及其与缺氧诱导因子-1a(HIF-1a)的关系,探讨人脑出血血肿周围组织损伤的分子机制.方法 选择行血肿清除术的脑出血患者32例,选取手术过程中获得的血肿周围脑组织,采用免疫组织化学技术、HE染色及TUNEL染色方法检测细胞色素C、HIF-1a的表达及凋亡细胞的变化.结果 出血4h可见神经元细胞及血管内皮细胞肿胀,出血12h可检测到明显的凋亡细胞,24~48h凋亡细胞明显增多,48~72h达到高峰;出血4h,血肿周围脑组织可见少量细胞色素C表达的神经元,48~72h时达到高峰;出血4h,血肿周围脑组织即可见散在HIF-1a表达的神经元,24~48h时达到高峰,48~72h高表达持续存在;细胞色素C的表达与HIF-1a的表达呈正相关性(r=0.83,t=8.32,P<0.01).结论脑出血后血肿周围组织脑血流量下降可引起细胞色素C的释放,产生缺血性病理损害.  相似文献   
994.
BACKGROUND: Epidemiological studies suggest that environmental adversity can alter parental care and thus influence child development. We addressed the question of whether stressors can directly affect parental behavior using a rodent model of stable, individual differences in maternal behavior. METHODS: Lactating rat mothers were characterized as high or low in pup-directed licking/grooming (LG) behavior, rebred, and subjected to 7 days of intermittent stress or control conditions during gestation. Female rats were mated a third time without any subsequent intervention. Maternal behavior, oxytocin receptor (OTR) binding, and offspring behavior were examined. RESULTS: Stress reduced OTR levels and pup LG of high LG mothers to levels comparable with those of low LG mothers. The adult offspring of the gestational stress/high LG mothers resembled those of low LG mothers on behavioral measures of anxiety and maternal behavior, as well as OTR levels. The results of the third mating revealed an enduring effect of gestational stress on both mother and offspring maternal LG. CONCLUSIONS: These findings suggest that stress can directly alter maternal care through the neuroendocrine systems that normally regulate this behavior. Thus, the effects of environmental adversity can be transmitted across generations through a nongenomic mechanism involving maternal care.  相似文献   
995.
乳腺癌组织中Cyclin D1及p16蛋白表达的联合检测及其意义   总被引:3,自引:1,他引:2  
目的:探讨乳腺癌中Cyclin D1及p16蛋白表达的相关性及其临床意义。方法:LSAB法检测多种乳腺组织中Cyclin D1及p16蛋白的表达情况,结合有关临床资料,分析Cyclin D1和p16蛋白表达异常与乳腺癌中重要的临床病理因素的关系。结果:62例乳腺癌组织中,Cyclin D1蛋白过度表达占48·4%,其表达与乳腺癌组织学分级呈明显正相关,且Cyclin D1蛋白过度表达更常见于ER、PR阳性的乳腺癌中。乳腺癌旁组织中Cyclin D1蛋白过度表达为20·0%,其他几种乳腺组织很少有CyclinD1蛋白的过度表达。p16蛋白仅在58·1%的乳腺癌组织中有表达,且p16的表达与组织学分级程度有负相关关系。正常乳腺组织中未见p16蛋白的异常。结论:乳腺癌组织中存在着Cyclin D1蛋白的过度表达及p16蛋白的异常,二者对乳腺癌组织的增殖分化有一定的影响。  相似文献   
996.
目的 探讨血吸虫病并结肠癌与ING1、p53、bcl-2基因之间的相关性及其可能的作用机制。方法采用免疫组化Envision法检测血吸虫病并结肠癌62例、无血吸虫病56例结肠癌中的ING1、p53、bcl-2的表达。结果在血吸虫病并结肠癌组中的ING1阳性表达率(35.5%)明显低于无血吸虫病结肠癌组(46.4%),结果有统计学意义(P〈0.05);而两组中的p53、bcl-2阳性表达率结果无统计学意义(P〉0.05)。结论血吸虫病患者的抑癌基因ING1的失活对结肠癌的发生有一定的影响。  相似文献   
997.
目的探讨扣带回立体定向毁损对甲基苯丙胺(MAP)大鼠脑内颞叶皮质多巴胺D2受体表达的影响。方法80只SD大鼠随机分为对照组、MAP组、MAP 毁损组和MAP 假毁损组,每组各20只;采用经腹腔注射MAP制备精神分裂症MAP模型,立体定向-射频毁损扣带回,免疫组织化学ABC法观察颞叶皮质D2受体的表达。结果与对照组比较,MAP组及MAP 假毁损组大鼠颞叶皮质D2受体表达差异有显著性(P<0.01);MAP 毁损组大鼠颞叶皮质DA受体阳性细胞数目与对照组比较差异无显著性(P>0.05)。结论扣带回毁损可以抑制使用MAP而诱发的颞叶皮质D2表达的亢进。  相似文献   
998.
目的:对趋化因子CXC受体4(CXCR4)在前列腺癌(PCa)组织以及PCa细胞系PC-3M中的表达进行研究。方法:提取正常前列腺组织、PCa组织和PC-3M细胞的总RNA,采用RT-PCR方法,于mRNA水平检测其CXCR4的表达情况;制备PC-3M细胞爬片和MCF-7细胞爬片(人乳腺癌细胞系,作为阳性对照),采用SABC免疫组织化学方法,于蛋白水平测定CXCR4在PC-3M细胞中的表达。结果:RT-PCR方法显示PC-3M细胞和PCa组织CXCR4 mRNA有较高水平的表达,正常前列腺组织未见CXCR4 mRNA的表达;SABC显示PC-3M细胞CXCR4蛋白呈强表达。结论:CXCR4在PCa组织和PC-3M细胞中有明显表达,在正常前列腺组织中无明显表达,CXCR4可能在PCa的发生发展中发挥重要作用。  相似文献   
999.
Metastasis-suppressor genes, by definition, suppress metastasis without affecting tumorigenicity and, hence, present attractive targets as prognostic or therapeutic markers. BRMS1 (breast cancer metastasis suppressor) has recently been identified as a metastasis-suppressor gene for human breast cancer and melanoma. Expression of BRMS1 messenger RNA (mRNA) in multitissue including normal prostate, ovarian, testis, and colon has been detected by northern blot analysis. We hypothesize that the role of BRMS1 in tumor progression may not be limited to breast cancer and melanoma. We previously found that BRMS1 mRNA levels in primary ovarian epithelial carcinomas were significantly lower than that in normal ovarian and benign tumors (P < 0.05), and statistical analysis of BRMS1 mRNA levels revealed that BRMS1 mRNA levels were significantly higher in early tumor stages (I, II) compared with advanced tumor stages (III, IV) in which lymph node or distant metastases were present (P < 0.01). Our data showed that reduced BRMS1 mRNA seems to influence ovarian carcinoma metastatic ability. Therefore, we transfected BRMS1 plasmid into highly malignant ovarian carcinoma cell line, HO-8910PM, and examined cell biologic behaviors including proliferation, adhesion, invasion, and metastasis in vitro and in vivo. BRMS1 expression did not alter the proliferation of HO-8910PM cells in vitro and primary tumor formation in vivo. But, BRMS1 expression significantly suppressed the cell adhesion to extracellular matrix components and in vitro cell invasion in BRMS1-transfected HO-8910PM cells compared to parental HO-8910PM and vector-only transfectants (HO-8910PM-vect). Furthermore, motility of BRMS1 transfectants was inhibited. lung colony formation of intravenously injected BRMS1 transfectants in nude mice was significantly reduced. Also, BRMS1 transfectants form significantly less metastatic to organs of peritoneal cavity in orthotopically implanted ovarian tumor nude models. We further discovered that BRMS1 expression did downregulate expression of an actin-bundling protein associated with cell motility -fascin, which perhaps is the mechanism underlying BRMS1 suppression of metastasis. These data suggested that in addition to its already described role in breast cancer and melanoma, BRMS1 functions as a metastasis-suppressor gene in ovarian carcinoma by modifying several metastatic-associated phenotypes, offering a new target for therapeutic intervention.  相似文献   
1000.
BACKGROUND: Histamine plays an important role in vascular disease. Tissue factor (TF) expression is induced in vascular inflammation and acute coronary syndromes. OBJECTIVES: This study examined the effect of histamine on tumor necrosis factor-alpha- (TNF-alpha-) vs. thrombin-induced endothelial TF expression. METHODS AND RESULTS: Histamine (10(-8)-10(-5) mol L-1), TNF-alpha (5 ng mL-1), and thrombin (1 U mL-1) induced TF expression in human endothelial cells. Although TF expression by TNF-alpha and thrombin was identical, histamine augmented TNF-alpha-induced expression 7.0-fold, but thrombin-induced expression only 2.6-fold. Similar responses occurred with TF activity. The H1-receptor antagonist mepyramine abrogated these effects. Differential augmentation by histamine was also observed at the mRNA level. Histamine-induced p38 activation preceded a weak second activation to both TNF-alpha and thrombin. Histamine-induced c-Jun NH2-terminal kinase (JNK) activation was followed by a strong second activation to TNF-alpha, and less to thrombin. Selective inhibition of this second JNK activation by SP600125 reduced TF induction to histamine plus TNF-alpha by 67%, but to histamine plus thrombin by only 32%. Histamine augmented TNF-alpha- and thrombin-induced vascular cell adhesion molecule 1 (VCAM-1) expression to a similar extent. Consistent with this observation, VCAM-1 induction to TNF-alpha and thrombin was mediated by p38, but not by JNK. CONCLUSIONS: Histamine differentially augments TNF-alpha- vs. thrombin-induced TF expression and activity, which is mediated by the H1-receptor, occurs at the mRNA level, and is related to differential JNK activation.  相似文献   
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