首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   32708篇
  免费   3012篇
  国内免费   2418篇
耳鼻咽喉   243篇
儿科学   266篇
妇产科学   332篇
基础医学   3811篇
口腔科学   499篇
临床医学   4748篇
内科学   4788篇
皮肤病学   252篇
神经病学   1738篇
特种医学   1091篇
外国民族医学   21篇
外科学   3005篇
综合类   5621篇
现状与发展   5篇
一般理论   2篇
预防医学   1901篇
眼科学   1201篇
药学   3637篇
  28篇
中国医学   2036篇
肿瘤学   2913篇
  2024年   124篇
  2023年   593篇
  2022年   1528篇
  2021年   1832篇
  2020年   1415篇
  2019年   1257篇
  2018年   1143篇
  2017年   1175篇
  2016年   1022篇
  2015年   1630篇
  2014年   1883篇
  2013年   1560篇
  2012年   2362篇
  2011年   2575篇
  2010年   1532篇
  2009年   1212篇
  2008年   1606篇
  2007年   1600篇
  2006年   1641篇
  2005年   1856篇
  2004年   1016篇
  2003年   877篇
  2002年   810篇
  2001年   696篇
  2000年   682篇
  1999年   784篇
  1998年   556篇
  1997年   529篇
  1996年   410篇
  1995年   378篇
  1994年   312篇
  1993年   221篇
  1992年   236篇
  1991年   214篇
  1990年   196篇
  1989年   149篇
  1988年   150篇
  1987年   106篇
  1986年   102篇
  1985年   66篇
  1984年   29篇
  1983年   25篇
  1982年   11篇
  1981年   20篇
  1980年   9篇
  1979年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
目的:观察3g/L盐酸洛美沙星眼凝胶的临床疗效及安全性。方法:对128例(203眼)细菌性结膜炎和细菌性角膜炎患者采用多中心、随机分组、平行对照试验,观察其主要症状体征消失情况、角膜炎症面积缩小情况、病原菌清除效果和不良反应。试验组(testgroup,TG)65例(103眼),对照组(controlledgroup,CG)63例100眼,分别应用3g/L盐酸洛美沙星眼凝胶和3g/L盐酸洛美沙星滴眼液。结果:①TG治愈率(80.6%)高于CG治愈率(65.0%);②TG(细菌性结膜炎)眼痛异物感消失率和消失时间(83.7%,5.33±2.00d)优于CG(64.1%,6.36±1.50d);TG(细菌性结膜炎)流泪消失率(91.8%)高于CG(75.0%);③记分统计表明:TG(细菌性结膜炎)结膜充血改善(平均下降1.76分)明显优于CG(平均下降1.25分);TG畏光消失情况(平均下降1.24分)好于CG(平均下降0.87分);TG(细菌性结膜炎)分泌物消失情况(平均下降1.64分)好于CG(平均下降1.33分);④其他情况两组间无明显差异。结论:3g/L盐酸洛美沙星眼凝胶治疗眼前段细菌感染安全、有效,对结膜炎症状体征的改善优于滴眼液。  相似文献   
92.
目的 探讨膀胱粘膜下层无细胞基质的制作与评价。方法 自膀胱解剖出膀胱粘膜下层,置于PBS、0.5%SDS、双蒸水中反复洗涤去除细胞,必要时加用胰蛋白酶消化。获得的细胞外基质采用HE、免疫组化、扫描电镜评价去细胞效果,细胞植入无细胞基质观察细胞能否粘附于该材料。结果 HE、免疫组化、扫描电镜均未见制备的材料中存在细胞及细胞碎片,体外细胞植入试验见细胞可粘附于材料并增殖。结论 采用本制备方法可以得到膀胱粘膜下层无细胞基质,有望为临床提供尿道下裂生物替代材料。  相似文献   
93.
Glial fibrillary acidic protein- (GFAP) and calbindin D28k-immunoreactivity (IR) were investigated in the medial subdivision of the nucleus of the solitary tract (mNST) of prenatally X-irradiated rats. Pregnant rats were exposed to a single whole-body X-irradiation on day 11 or 16 of gestation at a dose of 1. 3 Gy. The offspring were killed at 7-14 days of age for the immunohistochemical observations. Rat pups showed strong GFAP-IR at the level rostral to the obex when receiving X-rays on day 11 of gestation, with hypertrophy of astrocyte cell bodies and cytoplasmic processes, but weak GFAP-IR when receiving X-rays on day 16 of gestation. Calbindin D28k-IR was stronger in the animals receiving X-rays on day 11 or 16 of gestation compared to that in the control animals. In the present study, the increase of GFAP- and calbindin D28k-IR cells in the mNST might indicate that adaptative mechanisms are taking place to preserve integrated nervous system function and possibly, to provide neuroprotection.  相似文献   
94.
内皮素受体拮抗剂治疗充血性心衰一项meta分析   总被引:1,自引:0,他引:1  
目的初步评价内皮素拮抗剂治疗心衰的效果和安全性。方法借助循证医学检索途径和方法筛选出临床随机对照试验(RCTs),数据用Revman4.2软件进行分析。结果共入选13个临床随机对照试验(RCT)4137名患者,其中3个试验评价了心脏指数改善情况,5个试验评价死亡和心衰恶化,4个试验评价其它副作用。心脏指数改善的总效应为:WMD(加权均数差)0.47,95%可信区间(CI)[0.36,0.57](P<0.00001)。Tezosentan<50mg/h、50mg/h和100mg/h三组比较具有相似的效果及副作用,而副作用有随剂量增加的趋势。作为主要终点指标死亡率和心衰恶化两组相似(RR=1.00,95%CI[0.89,1.13](P=0.89),而其它副作用事件发生率则存在明显差异(RR=1.28,95%CI[1.13,1.44](P<0.0001)。结论内皮素拮抗剂可改善心衰患者的心脏指数,但长期效应尚未得到证实。治疗组患者副作用发生常见,并呈剂量依赖性。内皮素拮抗剂的长期效果还需要设计更完善、纳入例数更多的临床随机对照试验加以阐明。  相似文献   
95.
Protein kinase C (PKC) isoforms are increasingly recognized as playing important roles in the regulation of neuronal plasticity and survival. Recent findings from studies of non-neuronal cells suggest that atypical isoforms of PKC can modulate apoptosis in various paradigms. Because increasing data support a role for neuronal apoptosis in the pathogenesis of Alzheimer's disease (AD), we tested the hypothesis that PKCiota (PKCiota) can modify vulnerability of neural cells to apoptosis induced by amyloid beta-peptide (ABP), a cytotoxic peptide linked to neuronal degeneration in AD. Overexpression of PKCiota increased the resistance of PC12 cells to apoptosis induced by ABP. Associated with the increased resistance to apoptosis were improved mitochondrial function and reduced activity of caspases. In addition, ABP-induced increases in levels of oxidative stress and intracellular calcium levels were attenuated in cells overexpressing PKCiota. These findings suggest that PKCiota prevents apoptosis induced by ABP by interrupting the cell death process at a very early step, thereby allowing the cells to maintain ion homeostasis and mitochondrial function.  相似文献   
96.
It is a puzzle to many researchers that with so extensive resources, so advanced technology, and so urgent need the world over, so little has been done to alleviate the suffering of the people. Why is it so difficult to develop the prevention and health promotion strategies? This paper tries to discuss the issue.  相似文献   
97.
Objective: To investigate the distribution of TRPA1 (one kind of the TRP-like ion channel family) channel in the hippocampus and cerebral cortex of rat. Methods: RT-PCR was used to amplify the fragment of TRPA1 in the DRG (dorsal root ganglion), hippocampus and cerebral cortex of adult SD rat. In situ hybridization staining was used to show the distribution of TRPA1 mRNA in the hippocampus and cerebral cortex of adult rat brain. Results: Both RT-PCR and in situ hybridization staining showed that TRPA1 mRNA was expressed in hippocampus and cerebral cortex of the adult rat brain. Conclusion: Our results suggest that there is expression of TRPA1 mRNA both in the hippocampus and cerebral cortex of the adult rat brain.  相似文献   
98.
重型颅脑损伤病人病情危急,致残率、死亡率高,而医护人员的医德修养直接影响危重病人的治疗效果.也关系着医疗卫生行业的社会声誉,因而对临床伦理学有着更高、更严的要求,作者对在救治重型颅脑损伤病人过程中的伦理学问题进行了探讨。  相似文献   
99.
The type III voltage-gated sodium channel was cloned from human brain. The full-length cDNA has 89% identity with rat type III, and the predicted protein (1951 amino acids) has 55 differences. The expression pattern of human type III mRNA was determined in adult brain tissue and, in contrast to rat, was detected in many regions, including caudate nucleus, cerebellum, hippocampus and frontal lobe. The human type III channel was stably expressed in Chinese hamster ovary (CHO) cells and its biophysical properties compared to the human type II channel using identical conditions. The voltage dependence and kinetics of activation were found to be similar to that of type II. The kinetics of inactivation of the two human subtypes were also similar. However, type III channels inactivated at more hyperpolarized potentials and were slower to recover from inactivation than type II. When expressed in human embryonic kidney (HEK293T) cells, type III channels produced currents with a prominent persistent component, which were similar to those reported for rat type II [Ma et al. (1997) Neuron, 19, 443-452]. However, unlike type II, this was prominent even in the absence of coexpressed G-proteins, suggesting type III may adopt this gating mode more readily. The distinct properties of the channel, together with its wide distribution in adult brain, suggest that in humans, type III may have important physiological roles under normal, and perhaps also pathological conditions.  相似文献   
100.
谢幼红 《中医杂志》2005,46(5):361-362
目的:观察疏肝健脾法治疗纤维肌痛综合征(FMS)的临床疗效.方法:56例FMS患者分为A组38例(原发性)和B组18例(合并其他风湿病),给予逍遥散加减治疗,疗程12周.结果:A组总有效率为92.11%,B组总有效率为72.22%.两组比较,A组疗效优于B组(P<0.05),疼痛、压痛、僵硬、疲乏及睡眠障碍等明显改善(P<0.01).结论:疏肝健脾法治疗FMS具有较好的临床疗效,对原发性FMS作用尤为明显.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号