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   279898篇
  免费   23596篇
  国内免费   10310篇
耳鼻咽喉   1317篇
儿科学   9651篇
妇产科学   1944篇
基础医学   24857篇
口腔科学   3830篇
临床医学   28509篇
内科学   71151篇
皮肤病学   3087篇
神经病学   27369篇
特种医学   8595篇
外国民族医学   19篇
外科学   24211篇
综合类   40896篇
现状与发展   48篇
一般理论   9篇
预防医学   21891篇
眼科学   2658篇
药学   21600篇
  209篇
中国医学   14238篇
肿瘤学   7715篇
  2024年   571篇
  2023年   5277篇
  2022年   8015篇
  2021年   14223篇
  2020年   13281篇
  2019年   10532篇
  2018年   10487篇
  2017年   10730篇
  2016年   11450篇
  2015年   10857篇
  2014年   19762篇
  2013年   21343篇
  2012年   16464篇
  2011年   17965篇
  2010年   14053篇
  2009年   13505篇
  2008年   13543篇
  2007年   13204篇
  2006年   12037篇
  2005年   9932篇
  2004年   8319篇
  2003年   7187篇
  2002年   6155篇
  2001年   5352篇
  2000年   4449篇
  1999年   3792篇
  1998年   3623篇
  1997年   3188篇
  1996年   2859篇
  1995年   2545篇
  1994年   2384篇
  1993年   2027篇
  1992年   1904篇
  1991年   1650篇
  1990年   1373篇
  1989年   1181篇
  1988年   1088篇
  1987年   947篇
  1986年   841篇
  1985年   996篇
  1984年   858篇
  1983年   534篇
  1982年   635篇
  1981年   543篇
  1980年   435篇
  1979年   387篇
  1978年   306篇
  1977年   266篇
  1976年   250篇
  1975年   114篇
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
41.
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   
42.
??Objective    To discuss the influence of basic periodontal therapy on the level of IL-8?? IL-10 in serum and gingival crevicular fluid in patients who have chronic periodontitis complicated by coronary heart disease. Methods     A total of 65 cases of patients with chronic periodontitis complicated by coronary heart disease were selected and divided into two groups randomly??Group A of 35 patients who received the basic periodontal therapy and cardiac medical treatment??Group B of 30 patients who received cardiological treatment only. Then??select 25 patient who had developed chronic severe periodontitis with non-systematic disease to establish group C and give them the basic periodontal therapy only. Observe the changes of the IL-8??IL-10 levels in serum and gingival crevicular fluid and the periodontal infection indexes??BI??PD??. Results    The results showed that after three months of basic periodontal therapy the periodontal clinical indices of both group A and group C became better and the IL-8 level obviously reduced??while the IL-10 level obviously increased. There was no obvious difference between group A and group B in each examination index before the therapy. After three months??we found that the periodontal infection index??SBI PD??of group A was obviously better than group B. Compared to group B??the IL-8 level of group A obviously reduced??and the IL-10 level obviously increased. The difference was statistically significant??P < 0.05??. Conclusion    The basic periodontal therapy can effectively improve periodontal conditions of the patients with chronic periodontal diseases??and reduce the risk of breaking the normal cardiovascular function.  相似文献   
43.
Objective: The objective of this study is to evaluate the efficacy and safety of the clearing the lung and dissipating phlegm method in the treatment of acute exacerbation of chronic obstructive pulmonary disease(COPD) and to provide evidence for the treatment of the disease. Materials and Methods: Literature was searched from the United States National Library of Medicine(PubMed), Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database(Wanfang), and the Full?Text Database of Chinese Scientific and Technical Periodicals(VIP).A comprehensive collection was made of randomized controlled trials(RCTs) before June 2018, in which the treatment groups used either the clearing the lung and dissipating phlegm formulas only or combined it with routine Western medicine therapy, and the control group adopted routine Western medicine therapy only for the acute exacerbation of COPD. The Cochrane risk of bias method was used to evaluate the quality of the literature. The data were analyzed and retrieved independently by two reviewers before meta?analysis was carried out with RevMan 5.3 software to evaluate the primary outcome measures, including the total clinical effective rate, and the secondary outcome measures such as the pulmonary function(forced vital capacity [FVC], forced expiratory volume in the 1 s [FEV1], percentage of FEV1 [FEV1%], and FEV1/FVC)and blood gases(PaO_2 and PaCo_2). Results: A total of 13 RCTs involving 990 patients(496 in the treatment group and 494 in the control group)were included in this study. Meta?analysis revealed significant difference in the efficacy of the group that adopted solely the routine Western medicine method and the group that combined the Western medicine with the clearing the lung and dissipating phlegm method. Outcome measures including the pulmonary function(FVC, FEV1, FEV1%, and FEV1/FVC) and the blood gases(PaO_2 and PaCo_2) were significantly improved as compared to the control group(P 0.00001). However, adverse effects in the treatment group using combined traditional Chinese medicine were not reported due to the short observation time of the study. Conclusion: The clearing the lung and dissipating phlegm method can improve the efficacy in the treatment of acute exacerbation of COPD, the outcome measures of the pulmonary function and the blood gases,as well as the life quality of the patients. However, due to the fact that the existing studies are generally of poor quality in which randomization and its implementation were not properly carried out, more high?quality RCTs are necessary to confirm the findings of this study.  相似文献   
44.
45.
46.
目的:探索以系统化、标准化的新型冠状病毒核酸检测为核心和重要组成部分,建立适合于眼科医院新冠疫情精准防控切实可行的防控体系。方法:系列病例研究。自2020年2月24日至3月2日期间,以标准化病毒核酸检测联合血常规、C反应蛋白(CRP)、血清淀粉样蛋白A(SAA)等检测作为所有眼科手术患者术前筛查常规检测项目,同时也为返岗员工提供病毒核酸检测。设计调查问卷了解受检者对鼻咽拭子采样的接受度以及核酸检测结果对其心理状态的影响。结果:99例患者血液学检测结果有一定的异常比例,其中SAA检测结果增高13例,淋巴细胞计数减低12例、增高5例,白细胞计数增高11例、减低1例,CRP增高2例,新型冠状病毒核酸检测均阴性。33例本院职工新型冠状病毒核酸检测均阴性。12%的受访者对鼻咽拭子采样接受度评分较低。受检者在核酸检测前后思想压力评分较高的比例分别为46.7%和6.7%。结论:该项举措一方面为术前新冠病毒肺炎筛查及鉴别诊断提供了客观依据,很大程度上排除了隐性无症状感染者传播的可能,有利于减少二次传播的风险,降低院内交叉感染的概率;另一方面,核酸检测阴性结果有利于调整患者术前的心理状态并缓解医护人员在疫情防控期间的心理压力。  相似文献   
47.
随着社会的发展,人类生活方式的改变,高血压病越来越高发,具有低龄化趋势,代谢综合征常伴随发生,此种情况下的高血压往往是以舒张压升高为主,临床表现常与“亚健康”状态混淆,未能引起患者甚至部分医生的重视,然而事实上越来越多的科学研究证实舒张压高之危害十分明显,不容忽视。尽管现代医学对舒张压高的病因及病理机制有明确的阐述,但是暂时没有特效的药物。李延教授在治疗高血压病方面有着丰富的临床经验,临床中运用泽泻汤合温胆汤加减治疗舒张压高之眩晕,切中病机,加减灵活,屡有良效。文中从中医角度阐述舒张压高的病因病机,介绍李师辨病辨证思路,组方用药特点,附三则典型验案,另加个人心得体会,以期为舒张压高的有效治疗提供思路。  相似文献   
48.
Background: Gait disorders are common in Parkinson’s disease patients who respond poorly to dopaminergic treatment. Blockade of adenosine A2A receptors is expected to improve gait disorders. Istradefylline is a first-in-class selective adenosine A2A receptor antagonist with benefits for motor complications associated with Parkinson’s disease.

Research design and methods: This multicenter, open-label, single-group, prospective interventional study evaluated changes in total gait-related scores of the Part II/III Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) and Freezing of Gait Questionnaire (FOG-Q) in 31 Parkinson’s disease patients treated with istradefylline. Gait analysis by portable gait rhythmogram was performed.

Results: MDS-UPDRS Part III gait-related total scores significantly decreased at Weeks 4–12 from baseline with significant improvements in gait, freezing of gait, and postural stability. Significant decreases in MDS-UPDRS Part II total scores and individual item scores at Week 12 indicated improved daily living activities. At Week 12, there were significant improvements in FOG-Q, new FOG-Q, and overall movement per 48 h measured by portable gait rhythmogram. Adverse events occurred in 7/31 patients.

Conclusions: Istradefylline improved gait disorders in Parkinson’s disease patients complicated with freezing of gait, improving their quality of life. No unexpected adverse drug reactions were identified.

Trial registration: UMIN-CTR (UMIN000020288).  相似文献   

49.
目的 探讨不同年龄阿尔茨海默病(AD)患者ADC值与年龄的相关性。方法 选取30例AD患者(AD组)和年龄与之相匹配的30名志愿者(对照组),按年龄段各分为6个亚组[55~59岁(n=3)、60~64岁(n=4)、65~70岁(n=9)、71~74岁(n=5)、75~80岁(n=6)、>80岁(n=3)],测量双侧海马、红核、尾状核、杏仁体、壳核ADC值,并进行配对t检验、独立样本t检验、单因素方差分析及Pearson相关分析。结果 AD组红核左、右侧ADC值有统计学差异(P=0.022)。AD组不同年龄亚组右侧海马、双侧尾状核、右侧壳核ADC值差异有统计学意义(P均<0.05);2组不同年龄亚组双侧海马、壳核、尾状核ADC值差异有统计学意义(P均<0.05)。AD组右侧海马(r=0.615,P<0.001)、右侧壳核(r=0.653,P=0.001)及双侧尾状核(左侧:r=0.397,P=0.030;右侧:r=0.429,P=0.020)ADC值与年龄呈正相关。结论 AD患者右侧海马和壳核、双侧尾状核ADC值随年龄增加而增大。ADC值可为临床预测和早期诊断AD脑内右侧海马和壳核、双侧尾状核神经退行性病变提供参考。  相似文献   
50.
Endolymphatic hydrops features excess endolymph in the membranous labyrinth, and is a marker of Menière's disease. Between the early 1980s and late 2000s, MRI in Menière's disease aimed purely to rule out tumor or malformation as differential diagnoses for the pressure disorder. Progress in high-resolution MRI, however, now enables excess endolymph to be visualized in the membranous labyrinth, differentiating saccule and utricle in Menière's disease and in other clinical presentations such as cochleovestibular schwannoma. More recently, non-visibility of the saccule was demonstrated in a subgroup of Menière's disease patients, and utricle atelectasis in case of uni- or bilateral vestibular areflexia. Endolymph quantification remains highly controversial in terms of grading approach, but a simple semiology based on excess or deficient visualization of endolymph according to the compartment sheds light on the pathophysiological mechanisms of cochleovestibular disorder and may in future allow effective monitoring of medical and surgical treatment.  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