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   261270篇
  免费   9710篇
  国内免费   4454篇
耳鼻咽喉   3367篇
儿科学   8342篇
妇产科学   7096篇
基础医学   33638篇
口腔科学   7364篇
临床医学   23460篇
内科学   46021篇
皮肤病学   5349篇
神经病学   16002篇
特种医学   12964篇
外国民族医学   149篇
外科学   35801篇
综合类   9099篇
现状与发展   19篇
一般理论   6篇
预防医学   21083篇
眼科学   5991篇
药学   20307篇
  64篇
中国医学   3196篇
肿瘤学   16116篇
  2022年   2248篇
  2021年   3561篇
  2020年   2574篇
  2019年   2535篇
  2018年   6066篇
  2017年   5951篇
  2016年   5215篇
  2015年   7603篇
  2014年   7856篇
  2013年   6565篇
  2012年   14774篇
  2011年   10337篇
  2010年   5580篇
  2009年   6359篇
  2008年   5664篇
  2007年   6449篇
  2006年   6602篇
  2005年   14651篇
  2004年   15122篇
  2003年   10584篇
  2002年   5454篇
  2001年   5659篇
  2000年   3108篇
  1999年   7305篇
  1998年   1499篇
  1997年   1179篇
  1992年   7260篇
  1991年   7443篇
  1990年   7637篇
  1989年   7194篇
  1988年   6707篇
  1987年   6441篇
  1986年   6141篇
  1985年   5401篇
  1984年   3687篇
  1983年   2987篇
  1979年   3883篇
  1978年   2392篇
  1977年   1808篇
  1976年   1573篇
  1975年   2501篇
  1974年   3143篇
  1973年   2756篇
  1972年   2773篇
  1971年   2768篇
  1970年   2572篇
  1969年   2478篇
  1968年   2252篇
  1967年   2171篇
  1966年   1903篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
综述了脑血管介入术穿刺点压迫方法(包括人工压迫、弹力带加压、压迫器加压、血管闭合装置压迫、止血敷料压迫、气囊加压6种)、止血压力以及压迫时间,提出由于穿刺点和压迫方法的不同,其压迫时间、减压时间和压力大小等需要进一步探讨,为脑血管介入术后患者穿刺点的临床护理提供参考。  相似文献   
2.
Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T2-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T2-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T2-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T2 relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T2 was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T2 relaxation time was derived (R2 = 0.98): T2 (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T2-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T2-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.  相似文献   
3.
Lessons Learned
  • The overall safety profiles of ipilimumab 3 mg/kg and 10 mg/kg administered every 3 weeks, were consistent between Chinese patients with solid tumors in the current study and patients from previous U.S. ipilimumab monotherapy studies. No new safety signals were identified.
  • The mean systemic exposures to ipilimumab (assessed by first dose area under the curve during the dosing interval and maximum serum concentration) were numerically lower in the Chinese patient population than in U.S. patients for both 3 mg/kg and 10 mg/kg doses; however, the range of serum concentrations in the Chinese and U.S. populations overlapped (3 mg/kg and 10 mg/kg), suggesting that ipilimumab pharmacokinetics was ethnically insensitive in this study.
BackgroundThis phase I, open‐label study assessed ipilimumab safety, tolerability, pharmacokinetics (PK), immunogenicity, and antitumor activity in Chinese patients with unresectable, metastatic, recurrent malignant melanoma (MM) or nasopharyngeal carcinoma (NPC).MethodsOf 39 patients enrolled, 25 received ipilimumab (11 patients received 3 mg/kg, and 14 patients received 10 mg/kg). Reasons for not receiving treatment were withdrawal of consent (3 patients), no longer meeting the criteria (10 patients), and one recorded as “other.” During the induction phase, patients received ipilimumab (3 mg/kg, i.v.), on day 1 of a 3‐week cycle, to a maximum of four doses or progressive disease (PD). During the maintenance phase at week 24, patients received ipilimumab (3 mg/kg, i.v.) on day 1 of a 12‐week cycle, to a maximum of 3 years or PD. Considering the co‐primary safety and PK endpoints, the successive dosing required nine patients with two or fewer dose‐limiting toxicities during the 42‐day observation period to proceed with a new cohort of nine patients at 10 mg/kg.ResultsIpilimumab safety and PK profiles were similar in Chinese and predominantly White populations. Ipilimumab was well tolerated. Most adverse events (AEs) were grades 1–2 and experienced by 11 patients treated with 3 mg/kg and 14 patients treated with 10 mg/kg. There were no new safety concerns. Incidence of anti‐ipilimumab antibodies was low (1 of 10 in the 3 mg/kg patients and 2 of 13 in the 10 mg/kg patients) and without safety implications. In the 3 mg/kg group, 8 of 11 patients had PD. In the 10 mg/kg group (all NPC, 0 MM patients), 11 of 14 patients had PD. Three patients had stable disease (one at 3 mg/kg and two at 10 mg/kg).ConclusionIpilimumab was well tolerated in Chinese patients, showing similar safety and PK to previous studies in predominantly White populations.  相似文献   
4.
采用文献复习和实证研究经验的方法对《医疗质量管理办法》中涉及的医疗质量概念及相关问题进行探讨。《医疗质量管理办法》中的医疗质量的定义存在重大缺失,没有涉及医疗服务的结果,特别是患者安全。医疗质量的定义应与国际相关权威机构保持一致,应高度重视医疗服务的结果,特别是患者安全。  相似文献   
5.
Krüppel-like factor 16 (KLF16), a member of the Krüppel-like factor (KLF) family, has been extensively investigated in multiple cancer types. However, the role of KLF16 in oral squamous cell carcinoma (OSCC) remains unknown. Thus, we conducted this study to investigate its related mechanism. KLF16 expression in OSCC cell lines was quantified by western blotting. Then, OECM1 and OC3 cells were divided into Blank, siCtrl, siKLF16#1 and siKLF16#2 groups. Subsequently, cell proliferation was detected using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays, cell migration and invasion were detected with wound healing and Transwell assays, and cell cycle distribution and cell apoptosis were detected via flow cytometry. KLF16, p21, CDK4, Cyclin D1 and p-Rb expression was detected by western blotting. Finally, xenograft models were established in nude mice to observe the in vivo effects of KLF16 on OSCC. KLF16 protein expression was upregulated in OSCC cells. Compared to the cells in the Blank group, the OECM1 and OC3 cells in the siKLF16#1 group and siKLF16#2 group exhibited a sharp decrease in proliferation but a remarkable increase in apoptosis. Moreover, the proportion of cells in the G0/G1 phase notably increased and that in the S phase decreased, with evident decreases in cell invasion and migration. Moreover, KLF16, cyclin-dependent kinase 4 (CDK4), Cyclin D1 and p-Rb protein expression was upregulated, but p21 expression was downregulated. The mice in the siKLF16#1 and siKLF16#2 xenograft model groups exhibited slower tumour growth and smaller tumours with evident downregulation of Ki67 expression compared to the mice in the Blank group. KLF16 expression was upregulated in OSCC cells, and interfering with KLF16 led to cell cycle arrest, inhibited OSCC cell growth and promoted cell apoptosis.  相似文献   
6.
7.
Major depressive disorder is a serious and common neuropsychiatric disorder that affects more than 350 million people worldwide. Electroconvulsive therapy is the oldest and most effective treatment available for the treatment of severe major depressive disorder. Electroconvulsive therapy modifies structural network changes in patients with major depressive disorder and schizophrenia. And it can also affect neuroinflammatory responses and may have neuroprotective effects. Electroconvulsive therapy plays an irreplaceable role in the treatment of major depressive disorder.  相似文献   
8.
9.
This study investigated the hypocholesterolaemic effects of bitter melon aqueous extracts (BMAE) in vitro, the inhibitory effects of BMAE on pancreatic cholesterol esterase (CEase) and incorporation of cholesterol into micelles were investigated. BMAE decreased the in vitro micellar solubility of cholesterol in a dose-dependent manner. The conformation of CEase was investigated by means of circular dichroism (CD) and fluorescence. The result revealed the decrease of α-helix contents, increase of β-sheet and exposure of aromatic amino acid residuals. The incorporation of cholesterol into micelles was inhibited by BMAE. A complex was observed by transmission electron microscopy (TEM), which indicated interaction between cholesterol and BMAE. The result revealed that BMAE can play a role in decreased intestinal cholesterol absorption via inhibition of CEase, and of micelle formation.  相似文献   
10.
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