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   5906篇
  免费   313篇
  国内免费   34篇
耳鼻咽喉   122篇
儿科学   277篇
妇产科学   147篇
基础医学   528篇
口腔科学   245篇
临床医学   509篇
内科学   1315篇
皮肤病学   109篇
神经病学   292篇
特种医学   113篇
外科学   987篇
综合类   354篇
一般理论   5篇
预防医学   408篇
眼科学   197篇
药学   401篇
中国医学   32篇
肿瘤学   212篇
  2023年   81篇
  2022年   68篇
  2021年   431篇
  2020年   195篇
  2019年   220篇
  2018年   242篇
  2017年   162篇
  2016年   197篇
  2015年   254篇
  2014年   299篇
  2013年   298篇
  2012年   451篇
  2011年   424篇
  2010年   256篇
  2009年   207篇
  2008年   332篇
  2007年   333篇
  2006年   324篇
  2005年   295篇
  2004年   247篇
  2003年   225篇
  2002年   181篇
  2001年   56篇
  2000年   58篇
  1999年   41篇
  1998年   33篇
  1997年   20篇
  1996年   23篇
  1995年   15篇
  1994年   18篇
  1993年   9篇
  1992年   28篇
  1991年   22篇
  1990年   24篇
  1989年   16篇
  1988年   17篇
  1987年   13篇
  1986年   8篇
  1985年   10篇
  1984年   6篇
  1983年   9篇
  1979年   8篇
  1975年   6篇
  1974年   13篇
  1973年   8篇
  1972年   6篇
  1971年   5篇
  1970年   7篇
  1969年   7篇
  1966年   6篇
排序方式: 共有6253条查询结果,搜索用时 203 毫秒
101.
Self-rated health reflects a person’s integrated perception of health, including its biological, psychological, and social dimensions. It is a predictor of morbidity and mortality. To assess the current status of self-rated health and associated factors in the Kingdom of Saudi Arabia, we analyzed data from the Saudi Health Interview Survey. We conducted a large national survey of adults aged 15 years or older. A total of 10,735 participants completed a standardized health questionnaire. Respondents rated their health with a five-point scale. Data on socio-demographic characteristics, chronic diseases, health-related habits and behaviors, and anthropometric measurements were collected. Associated factors of self-rated health were analyzed using a backward elimination multivariate logistic regression model. More than 77 % of respondents rated their health as excellent/very good. Female sex [odds ratio (OR) 1.52, 95 % confidence interval (CI) 1.24–1.88], decades of age (OR 1.35, 95 % CI 1.25–1.46), diagnosed diabetes mellitus (OR 1.54, 95 % CI 1.22–1.93), diagnosed hypercholesterolemia (OR 1.37, 95 % CI 1.06–1.79), diagnosed hypertension (OR 1.55, 95 % CI 1.22–1.96), number of other diagnosed chronic diseases (OR 1.69, 95 % CI 1.41–2.03), limited vigorous activity (OR 3.59, 95 % CI 2.84–4.53), need for special equipment (OR 2.62, 95 % CI 1.96–3.51), and more than 3 h of daily television/computer screen time (OR 1.59, 95 % CI1.11–2.29) were positively associated with poor/fair health. Smoking, obesity, and physical inactivity were not associated with self-reported health. We found that preventable risk factors are not associated with Saudis’ self-rated health. This optimistic perception of health poses a challenge for preventive interventions in the Kingdom and calls for campaigns to educate the public about the harm of unhealthy behaviors.  相似文献   
102.
103.
Three randomised controlled trials in Africa indicated that voluntary medical male circumcision (VMMC) is an effective method to reduce a man's risk of becoming infected through sex with an HIV-positive female partner. The success of recent public health initiatives to increase numbers of circumcised men in Malawi has been very limited. We conducted in-depth interviews and focus group discussions (FGDs) with men, women and male adolescents from non-circumcising and circumcising communities in southern Malawi to better understand their beliefs about male circumcision and the promotion of VMMC for HIV prevention. Results revealed that beliefs about male circumcision, in general, are strongly mediated by Malawian culture and history. Participants have attempted to develop a new meaning for circumcision in light of the threat of HIV infection and the publicised risk reduction benefits of VMMC. Several study participants found it difficult to distinguish VMMC from traditional circumcision practices (jando and lupanda), despite awareness that the new form of circumcision was an expression of (western) modern medicine performed largely for public health purposes. Greater recognition of background cultural beliefs and practices could inform future efforts to promote medical male circumcision as an HIV prevention strategy in this context.  相似文献   
104.
The aim of this study is to report clinical and imaging findings, and treatment outcomes of a patient with nodular posterior scleritis. A 41-year-old woman was diagnosed as nodular posterior scleritis in the light of clinical and imaging findings. At first admission best corrected visual acuity was 20/50 in her right eye. Fundus examination revealed an amelanotic subretinal mass under the superior temporal arcade associated with subretinal fluid surrounding it. B-scan ultrasonography, optical coherence tomography, fluorescein angiography, and indocyanine green angiography findings confirmed the diagnosis. As treatment, nepafenac eye drops 3 times a day, and flurbiprofen tablet 100 mg twice a day were prescribed. After 4 weeks of treatment, the ocular pain was relieved, BCVA improved to 20/20, and subretinal mass totally regressed. Although the diagnosis of nodular posterior scleritis may be confusing, it has to be kept in mind in patients with a subretinal/choroidal mass. Multimodal fundus imaging may be helpful in differential diagnosis. The condition is usually curable with non-steroidal anti-inflammatory drugs and/or systemic steroids.  相似文献   
105.

Background and Purpose

Abrupt discontinuation of nicotine, the main psychoactive component in tobacco, induces a withdrawal syndrome in nicotine-dependent animals, consisting of somatic and affective signs, avoidance of which contributes to drug maintenance. While blockade of fatty acid amide hydrolase, the primary catabolic enzyme of the endocannabinoid arachidonoylethanolamine (anandamide), exacerbates withdrawal responses in nicotine-dependent mice, the role of monoacylglycerol lipase (MAGL), the main hydrolytic enzyme of a second endocannabinoid 2-arachidonylglycerol (2-AG), in nicotine withdrawal remains unexplored.

Experimental Approach

To evaluate the role of MAGL enzyme inhibition in nicotine withdrawal, we initially performed a genetic correlation approach using the BXD recombinant inbred mouse panel. We then assessed nicotine withdrawal intensity in the mouse after treatment with the selective MAGL inhibitor, JZL184, and after genetic deletion of the enzyme. Lastly, we assessed the association between genotypes and smoking withdrawal phenotypes in two human data sets.

Key Results

BXD mice displayed significant positive correlations between basal MAGL mRNA expression and nicotine withdrawal responses, consistent with the idea that increased 2-AG brain levels may attenuate withdrawal responses. Strikingly, the MAGL inhibitor, JZL184, dose-dependently reduced somatic and aversive withdrawal signs, which was blocked by rimonabant, indicating a CB1 receptor-dependent mechanism. MAGL-knockout mice also showed attenuated nicotine withdrawal. Lastly, genetic analyses in humans revealed associations of the MAGL gene with smoking withdrawal in humans.

Conclusions and Implications

Overall, our findings suggest that MAGL inhibition maybe a promising target for treatment of nicotine dependence.  相似文献   
106.
107.
Clinical Rheumatology - Although latent tuberculosis infection (LTBI) treatment is given before anti-tumor necrosis factor (TNF) treatment, tuberculosis (TB) still develops in these patients and...  相似文献   
108.
BackgroundSevere aortic stenosis (AoS) is considered a primary cause of syncope. However, other mechanisms may be present in these patients and accurate diagnosis can have important clinical implications. The aim of this study is to assess the different etiologies of syncope in patients with severe AoS and the impact on prognosis of attaining a certain or highly probable diagnosis for the syncope.MethodsOut of a cohort of 331 patients with AoS and syncope, 61 had severe AoS and were included in the study. Main cause of syncope and adverse cardiac events were assessed.ResultsIn 40 patients (65.6%), we reached a certain or highly probable diagnosis of the main cause of the syncope. AoS was considered the primary cause of the syncope in only 7 patients (17.5% of the patients with known etiology). Atrioventricular block (14 patients, 35.0%) and vasovagal syncope (6 patients, 15.0%) were the most frequently diagnosed causes. The presence of a known cause for syncope during the admission was not associated with a lower incidence of recurrence during follow-up (hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.20-2.40). Syncope of unknown etiology was independently associated with greater mortality during 1-year follow-up (HR 5.4, 95% CI 1.3-21.6) and 3-year follow-up (HR 3.5, 95% CI 1.2-10.3).ConclusionsIn a high proportion of patients with severe AoS admitted for syncope, the valvulopathy was not the main cause of the syncope. Syncope in two-thirds of this population was caused by either bradyarrhythmia or reflex causes. Syncope of unknown cause was associated with increased short- and medium-term mortality, independently from treatment of the valve disease. An exhaustive work-up should be conducted to determine the main cause for syncope.  相似文献   
109.
Heart Failure Reviews - Previous primary studies have explored the association between blood pressure (BP) and mortality in ambulatory heart failure (HF) patients reporting varying and contrasting...  相似文献   
110.
BACKGROUND: The relation between systolic pulmonary artery pressure (PAP) and mitral stenosis (MS) has been poorly understood. Although the mitral valve area (MVA) is an important factor affecting the PAP, there is a wide spectrum of the PAP in patients with MS despite a similar MVA. So, we analyzed whether the left and right ventricular myocardial performance index (MPI) correlated with the PAP. METHODS: Two-dimensional Doppler echocardiography was performed in 46 patients with MS. The left atrial diameter, mean mitral gradient, and MVA were measured. The PAP was derived from the tricuspid regurgitant jet velocity. The ejection time (ET), isovolumetric relaxation time (IRT), and contraction time (ICT) were measured on annulus of interventricular septum, lateral, inferior and anterior wall of left ventricle, and right ventricle free wall from apical two- and four-chamber views in patients with MS and 40 age-matched healthy patients by tissue Doppler imaging (TDI). Then the MPI was calculated as (IRT + ICT)/ET for both left and right ventricle. The correlation of PAP with MVA, mean mitral gradient, left atrial diameter, and left and right ventricular MPI was evaluated. RESULTS: MVA and PAP were measured as 1.57 +/- 0.39 cm2 (0.8-2.5 cm2)and 42 +/- 16 mmHg, respectively. It was determined that the MPI increased in patients with MS(0.59 +/- 0.1 vs 0.48 +/- 0.07, P < 0.001). It was also demonstrated that the MVA, left atrial diameter, mean diastolic gradient, and left ventricular MPI were correlated with PAP(r =-0.39 [P = 0.007], r = 0.43 [P = 0.003], r = 0.58 [P < 0.001], and r = 0.65 [P < 0.001], respectively). In multivariate analysis, although the PAP correlated with mean diastolic gradient and MPI (r = 0.39 [P = 0.013], and r = 0.48 [P < 0.001]), it did not correlate with left atrial diameter and MVA. The PAP also correlated with right ventricular MPI(r = 0.63 [P < 0.001]). CONCLUSION: This study demonstrates that the left ventricular MPI obtained by TDI is an important marker of PAP, and right ventricular MPI correlates with the PAP in patients with MS.  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