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   6803篇
  免费   674篇
  国内免费   545篇
耳鼻咽喉   45篇
儿科学   51篇
妇产科学   58篇
基础医学   814篇
口腔科学   99篇
临床医学   891篇
内科学   933篇
皮肤病学   74篇
神经病学   407篇
特种医学   263篇
外国民族医学   8篇
外科学   686篇
综合类   1179篇
现状与发展   5篇
预防医学   469篇
眼科学   311篇
药学   793篇
  1篇
中国医学   336篇
肿瘤学   599篇
  2024年   15篇
  2023年   100篇
  2022年   191篇
  2021年   360篇
  2020年   254篇
  2019年   243篇
  2018年   234篇
  2017年   212篇
  2016年   221篇
  2015年   324篇
  2014年   400篇
  2013年   329篇
  2012年   525篇
  2011年   560篇
  2010年   314篇
  2009年   280篇
  2008年   345篇
  2007年   389篇
  2006年   298篇
  2005年   338篇
  2004年   248篇
  2003年   253篇
  2002年   223篇
  2001年   216篇
  2000年   211篇
  1999年   206篇
  1998年   90篇
  1997年   100篇
  1996年   69篇
  1995年   49篇
  1994年   52篇
  1993年   28篇
  1992年   44篇
  1991年   36篇
  1990年   24篇
  1989年   38篇
  1988年   27篇
  1987年   25篇
  1986年   21篇
  1985年   20篇
  1984年   9篇
  1983年   6篇
  1982年   6篇
  1975年   6篇
  1974年   7篇
  1973年   7篇
  1972年   11篇
  1971年   7篇
  1970年   9篇
  1968年   5篇
排序方式: 共有8022条查询结果,搜索用时 210 毫秒
1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。  相似文献   
2.
ABSTRACT

Objective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group.

Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared.

Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group.

Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients.  相似文献   
3.
4.
The objective of the present study was to evaluate the clinical, radiological, and functional outcomes of a subscapularis transthoracic surgical approach and a posterolateral surgical approach with debridement, bone graft fusion, and internal fixation for the treatment of upper thoracic tuberculosis.There is currently debate over the best surgical approach for the treatment of upper thoracic tuberculosis. Traditionally, the subscapularis transthoracic approach has been preferred; however, the posterolateral approach has gained popularity in the past few years.A prospective, consecutive cohort of 43 upper thoracic tuberculosis patients with a mean age of 39 years (range: 20–52 years) was followed up for a minimum of 12 months (range: 12–60 months). Patients were randomly divided into 2 groups. Group A (n = 21) was treated by the subscapularis transthoracic approach and group B (n = 22) was treated by the posterolateral approach. All cases were evaluated for clinical, radiological, and functional outcomes. Intraoperative blood loss, operative duration, intraoperative and postoperative complications, hospital stay, the cure rate, fusion time, and the Frankel scale were used for clinical and functional evaluation, whereas the kyphosis angle was used for radiological evaluation.Grafted bones were fused by 10 months in all cases. There was no statistically significant difference between groups before surgery in terms of gender, age, segmental tuberculosis, erythrocyte sedimentation rate (ESR), Frankel scale, or Cobb''s angle (P > 0.05). The average operative duration for Group B was lower than that of Group A. There were no significant differences in intraoperative blood loss, intraoperative and postoperative complications, hospital stay, grafted bone fusion time, or cure rate between groups (P > 0.05). The Cobb''s angle correction rate for group B (68.5%) was significantly better than that of group A (30.9%). The neurological score showed significant postoperative improvement in both groups, with no significant difference between the groups.The subscapularis transthoracic approach and the posterolateral approach with debridement, bone graft fusion, and internal fixation are both sufficient and satisfactory for the surgical treatment of upper thoracic tuberculosis. However, the posterolateral approach is superior to the subscapularis transthoracic approach in terms of surgical trauma, operative time, and kyphosis correction.  相似文献   
5.
Transmural electrical dispersion determines the repolarization sequence across the ventricular wall, and plays an important role in the development of arrhythmias under pathological conditions. While it is clear that the transmural gradient of the transient outward current ( I to) underlies the dramatic difference in phase 1 repolarization across the ventricle, its contribution to the transmural action potential duration (APD) dispersion is not clear. We investigated this problem using the dynamic clamp technique in canine ventricular myocytes. The dynamic clamp allows quantitative 'insertion' of simulated conductances in real, biological cells, bridging pure computer modelling and experimental electrophysiology. 'Insertion' of an epicardial level of I to in endocardial cells produced a prominent phase 1 repolarization and a 'spike-and-dome' action potential morphology, but did not significantly affect the APD. Increasingly larger I to densities prolonged, and then dramatically shortened the endocardial APD. We also used the dynamic clamp to subtract, or 'block' the native I to in epicardial cells. Such 'blockade' eliminated the epicardial action potential notch, but had no significant effect on the APD. We conclude that I to, while being a key regulator of phase 1 repolarization, does not significantly affect the APD of canine ventricular myocytes, and that the I to gradient is not a significant contributor to the transmural APD dispersion in the canine ventricle. By allowing computer simulation on a biological background, the dynamic clamp is a new and effective tool to study the ionic basis of the electrical properties of cardiac cells.  相似文献   
6.
中风毒邪论是一种与传统中医中风病理有所不同的理论 ,在中风毒邪论指导下形成解毒通络方是较为理想的神经保护剂 ,可解决目前神经保护治疗的主要障碍 ,有望成为提高中医治疗中风急性期疗效的关键  相似文献   
7.
取正常成人心脏瓣膜36个,置于低浓度广谱抗生素的营养液(RP-MI1640细胞培养液)中灭菌48h,-80℃冰箱初冻,置于液氮中长期保存。灭菌前后瓣膜细菌培养阴性率分别为94.3%和100%,解冻后经光镜、电镜检查证实瓣组织细胞结构正常,组织培养葡萄糖消耗率测定示瓣组织存活良好。临床同种心脏瓣膜原位移植3例,随访6~30个月,瓣功能良好  相似文献   
8.
卷柏抗肿瘤药理作用研究   总被引:16,自引:0,他引:16  
目的:为寻找高效低毒的抗肿瘤药物,探究卷柏抗肿瘤的药理作用。方法:采用卷柏水提物及其各个萃取部位对小鼠肉瘤S180,肝癌H22模型腹腔注射给药,并观察两肿瘤体重量变化。实验结果表明:卷柏水提取物及其各个萃取部位对两种瘤株均有不同程度的抑制作用,其中JB-W-2(水萃取部位)作用最强,且存在着剂量依赖性;其次是JB-W-3在大剂量时仅对肉瘤呈现较强的抑制作用。  相似文献   
9.
目的:比较联合吸入沙丁胺醇与布地奈德和双倍吸入沙丁胺醇在治疗轻中度支气管哮喘患者的临床疗效。方法:80例患者随机分成两组:①观察组沙丁胺醇6~12m g/d加用布地奈德400~800ug/d,每日两次;②对照组沙丁胺醇双倍使用即剂量为12~24 m g/d,每日两次。疗程均为8周。结果:观察组患者临床症状明显缓解,早、晚最大呼气流量(PEF)改善,较对照组有明显统计学差异(P<0.05)。药物不良反应观察组与对照组之间无统计学差异。结论:沙丁胺醇、布地奈德联合应用,通过两者之间协调互补可有效改善肺功能,使哮喘患者得到很好治疗。  相似文献   
10.
观察保肾口服液对IgA肾病小鼠T细胞^3H-TdR掺入及其分泌IL-2水平的影响,结果表明低、中、高3种浓度的保肾口服液均能显著促进IgA肾病小鼠的自发性和ConA刺激的T细胞^3H-TdR掺入,促进T细胞合成,分泌IL-2,提前给药作用相同。提示保肾口服液有显著增强IgA肾病小鼠细胞免疫功能的作用。  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