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   504294篇
  免费   50748篇
  国内免费   33307篇
耳鼻咽喉   4322篇
儿科学   7060篇
妇产科学   6021篇
基础医学   50781篇
口腔科学   10988篇
临床医学   72209篇
内科学   67563篇
皮肤病学   5888篇
神经病学   23391篇
特种医学   18439篇
外国民族医学   246篇
外科学   44975篇
综合类   95249篇
现状与发展   122篇
一般理论   37篇
预防医学   41197篇
眼科学   13739篇
药学   53662篇
  619篇
中国医学   33731篇
肿瘤学   38110篇
  2024年   1847篇
  2023年   7987篇
  2022年   18639篇
  2021年   23773篇
  2020年   19595篇
  2019年   14977篇
  2018年   16355篇
  2017年   16427篇
  2016年   15068篇
  2015年   23212篇
  2014年   28872篇
  2013年   27814篇
  2012年   38752篇
  2011年   42864篇
  2010年   31032篇
  2009年   26310篇
  2008年   29618篇
  2007年   28892篇
  2006年   27225篇
  2005年   25330篇
  2004年   16757篇
  2003年   15974篇
  2002年   13083篇
  2001年   11243篇
  2000年   10466篇
  1999年   10134篇
  1998年   6582篇
  1997年   6379篇
  1996年   5085篇
  1995年   4601篇
  1994年   3919篇
  1993年   2575篇
  1992年   2869篇
  1991年   2529篇
  1990年   2152篇
  1989年   1871篇
  1988年   1571篇
  1987年   1459篇
  1986年   1146篇
  1985年   845篇
  1984年   483篇
  1983年   395篇
  1982年   236篇
  1981年   247篇
  1980年   167篇
  1979年   196篇
  1978年   107篇
  1977年   96篇
  1976年   66篇
  1974年   69篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
62.
63.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
64.
65.
66.
The purpose of this meta-analysis is to compare the relative merits among laparoscopic-assisted operations and laparotomy operations for patients with Hirschsprung disease.PubMed, Web of Science, and Wanfang databases were searched for the related articles. We analyzed dichotomous variables by estimating odds ratios (ORs) with their 95% confidence intervals (CIs) and continuous variables using the weighted mean difference (WMD) with the 95% CI. The random-effects model (REM) was used to combine the results. The outcome measures included operating time (OT), estimated blood loss (EBL), length of hospital stay (LOHS), mean first bowel movement (MFBM), and number of complications.Sixteen articles were included in the meta-analysis. These studies involved a total of 774 patients, 396 of whom underwent laparoscopic-assisted operations and 378 of whom underwent laparotomy operations. The EBL (WMD = −1.48, 95% CI = −1.82, −1.13), LOHS (WMD = −0.67, 95% CI = −0.86, −0.49), MFBM (WMD = −0.83, 95% CI = −1.05, −0.61), and number of complications (OR = 0.60, 95% CI = 0.40, 0.89) were significantly lower in laparoscopic-assisted operations than in laparotomy operations. The OT (WMD = 0.12, 95% CI = −0.05, 0.28) showed no significant differences between laparoscopic-assisted operations and laparotomy operations.Compared with laparotomy operations, laparoscopic-assisted operations are generally safer and more reliable for patients with Hirschsprung disease.  相似文献   
67.
目的 分析H型高血压患者的舌面诊图像颜色参数特征,探讨H型高血压患者的舌诊、面诊变化规律。方法 运用上海中医药大学自行研制的Smart TCM-1型中医舌面一体仪,采集高血压患者舌面诊图像,提取特征参数,分析健康对照组、H型高血压组与非H型高血压组患者舌面颜色参数特征。结果 ①在舌色各项参数中,H型高血压组舌尖部R值、B值、V值均显著小于健康对照组(P < 0.01);非H型高血压组舌尖部B值显著小于健康对照组(P < 0.01),S值较健康对照组显著增大(P < 0.05);H型高血压组舌尖部R、V值均明显小于非H型高血压组(P < 0.05)。在舌苔各项参数中,H型高血压组舌中H值、V值均明显小于健康对照组(P < 0.05);非H型高血压组舌中V值、舌右V值均显著小于健康对照组(P < 0.01);H型高血压组舌中H值明显小于非H型高血压组(P < 0.05),右侧舌苔S值明显大于非H型高血压组(P < 0.05)。②H型高血压组面色参数鼻G值、下颌G值、口唇R值、口唇V值均明显小于健康对照组(P < 0.05);非H型高血压组前额H值、目眶H值、脸颊H值、鼻H值、下颌H值、整体H值均明显大于健康对照组(P < 0.05);H型高血压组前额H值、目眶G值、目眶H值、脸颊H值、鼻G值、鼻H值、下颌R值、下颌G值、下颌H值、下颌V值、口唇R值、口唇G值、口唇V值、整体R值、整体G值、整体H值、整体V值均明显小于非H型高血压组(P < 0.05)。结论 H型高血压患者苔色偏黄,以舌中部为主,且舌右侧黄苔积聚较明显;H型高血压患者面色为黄中带红,口唇、下颌部更为晦暗。H型高血压患者的舌、面诊特征参数的变化,与高血压病阳亢湿盛病机相符。  相似文献   
68.
目的:研究滋阴清热方治疗对甲状腺功能亢进症阴虚火旺证患者疗效、血浆内皮素-1、炎症因子和免疫功能的影响。方法:将广州市花都区妇幼保健院收治的100例甲状腺功能亢进症阴虚火旺证患者分成观察组和对照组。对照组:给患者使用常规药物治疗;观察组:在对照组的基础上,给予滋阴清热方治疗。干预后,比较两组患者的临床疗效、血浆内皮素-1(Endothelin,ET)、炎症因子[白介素-2(Interleukin-2,IL-2)、白介素-8(Interleukin-8,IL-8)]及肿瘤坏死因子(Tumour Necrosis Factor-α,TNF-α)和免疫功能(CD3^+、CD4^+、CD8^+及CD4^+/CD8^+)。结果:干预前,两组患者IL-2、IL-8及TNF-α无变化,差异无统计学意义(P>0.05);干预后,观察组患者的IL-2比对照组高,且对照组的IL-8及TNF-α比观察组的高,P<0.05,差异有统计学意义;干预前,两组患者的CD3^+、CD4^+、CD8^+及CD4^+/CD8^+与ET无变化;干预后,观察组的CD3^+、CD4^+、CD8+及CD4^+/CD8^+比对照组高,P <0.05,差异有统计学意义,且观察组的ET低于对照组且观察组总有效率明显高于对照组。结论:滋阴清热方治疗降低了血浆内皮素-1,减少炎症的出现,提高免疫功能。  相似文献   
69.
The ban of lead in many electronic products and the expectation that, sooner or later, this ban will include the currently exempt piezoelectric ceramics based on Lead-Zirconate-Titanate has motivated many research groups to look for lead-free substitutes. After a short overview on different classes of lead-free piezoelectric ceramics with large strain, this review will focus on Bismuth-Sodium-Titanate and its solid solutions. These compounds exhibit extraordinarily high strain, due to a field induced phase transition, which makes them attractive for actuator applications. The structural features of these materials and the origin of the field-induced strain will be revised. Technologies for texturing, which increases the useable strain, will be introduced. Finally, the features that are relevant for the application of these materials in a multilayer design will be summarized.  相似文献   
70.
This meta-analysis examined whether early decompressive craniectomy (DC) can improve control of intracranial pressure (ICP) and mortality in patients with traumatic brain injury (TBI).Medline, Cochrane, EMBASE, and Google Scholar databases were searched until May 14, 2015, using the following terms: traumatic brain injury, refractory intracranial hypertension, high intracranial pressure, craniectomy, standard care, and medical management. Randomized controlled trials in which patients with TBI received DC and non-DC medical treatments were included.Of the 84 articles identified, 8 studies were selected for review, with 3 randomized controlled trials s having a total of 256 patients (123 DCs, 133 non-DCs) included in the meta-analysis. Patients receiving DC had a significantly greater reduction of ICP and shorter hospital stay. They also seemed to have lower odds of death than patients receiving only medical management, but the P value did not reach significance (pooled odds ratio 0.531, 95% confidence interval 0.209–1.350, Z = 1.95, P = 0.183) with respect to the effect on overall mortality; a separate analysis of 3 retrospective studies yielded a similar result.Whereas DC might effectively reduce ICP and shorten hospital stay in patients with TBI, its effect in decreasing mortality has not reached statistical significance.  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