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   1066篇
  免费   44篇
  国内免费   8篇
耳鼻咽喉   20篇
儿科学   94篇
妇产科学   38篇
基础医学   81篇
口腔科学   63篇
临床医学   73篇
内科学   243篇
皮肤病学   17篇
神经病学   86篇
特种医学   48篇
外科学   165篇
综合类   15篇
预防医学   27篇
眼科学   45篇
药学   55篇
肿瘤学   48篇
  2024年   1篇
  2023年   4篇
  2022年   11篇
  2021年   23篇
  2020年   17篇
  2019年   28篇
  2018年   28篇
  2017年   22篇
  2016年   33篇
  2015年   32篇
  2014年   34篇
  2013年   64篇
  2012年   65篇
  2011年   77篇
  2010年   31篇
  2009年   43篇
  2008年   86篇
  2007年   81篇
  2006年   103篇
  2005年   77篇
  2004年   64篇
  2003年   65篇
  2002年   38篇
  2001年   14篇
  2000年   4篇
  1999年   10篇
  1998年   5篇
  1997年   6篇
  1996年   3篇
  1995年   10篇
  1994年   1篇
  1993年   4篇
  1992年   5篇
  1991年   5篇
  1990年   2篇
  1989年   2篇
  1988年   3篇
  1987年   1篇
  1986年   2篇
  1985年   4篇
  1984年   2篇
  1979年   1篇
  1977年   1篇
  1976年   2篇
  1974年   3篇
  1972年   1篇
排序方式: 共有1118条查询结果,搜索用时 46 毫秒
91.
92.
Since little is known concerning regulation of immunological parameters in rapid changing psychiatric states like panic attacks, we measured cytokines at different time points in healthy subjects, which underwent experimental panic induction using the CCK-4 paradigm. Apart from a challenge related IL-6 increase, we could not observe any changes of neuroimmunological markers in relation to acute anxiety with regard to time and group. Herein we conducted for the first time a new approach to immunological research in panic disorder, suggesting immune changes are more related to long term disease stress.  相似文献   
93.
94.
Interferon-gamma is the most important cytokine in resistance to mycobacterial diseases and common variants of interferon-gamma gene could be related to tuberculosis susceptibility. We tested the hypothesis that the interferon-gamma+874T-A polymorphism is associated with tuberculosis disease, and affects the interferon-gamma response. We determined by pyrosequencing the distribution of the interferon-gamma+874T-A polymorphism in a Turkish population of 319 patients with pulmonary tuberculosis, 42 children with severe forms of tuberculosis and 115 healthy donors. We also analysed whether any correlation exists between this polymorphism and interferon-gamma response to Mycobacterium tuberculosis antigens by ELISPOT in 58 pulmonary tuberculosis cases, and the results were analysed according to the genotypes. We found that the minor allele (T) frequency was significantly lower in patients with pulmonary tuberculosis when compared to controls (P=0.024, OR=0.7), a similarly significant decrease in the frequency of TT genotype was observed in patients with pulmonary tuberculosis, compared to the control group (P=0.02, OR=0.49). IFN-gamma responses to PPD antigen in TT genotype was found to be significantly higher than the AA group (P>0.001). Non-parametric correlation analysis of ELISPOT data showed significant reverse correlation in PPD, CFP10 and ESAT6 values and IFN-gamma +874 genotypes. These results show that the IFN-gamma +874T-A polymorphism is related to the IFN-gamma response and the magnitude of the response decreases during transition from TT- to TA and to AA genotypes. Our data suggest that similar to various Caucasian populations, in a Turkish population the IFN-gamma+874 T-A polymorphism is also associated with tuberculosis disease and affects the magnitude of the IFN-gamma response.  相似文献   
95.
Antidepressants such as SSRIs or mirtazapine have been demonstrated to increase the concentrations of 3alpha-reduced neuroactive steroids throughout several weeks of treatment. However, no data are available on the impact of mood stabilizers such as lithium or carbamazepine on neuroactive steroid levels in depressed patients. Study 1 was performed in 26 drug-free depressed inpatients who were treated with either mirtazapine monotherapy (n=13) or combination therapy with mirtazapine and addition of lithium (n=13). Twenty drug-free depressed inpatients were included in study 2, receiving either mirtazapine monotherapy (n=10) or combination treatment with mirtazapine and carbamazepine (n=10). Plasma samples were taken weekly at 0800 h in the morning and quantified for neuroactive steroids by means of combined gas chromatography/mass spectrometry analysis. In study 1, the mirtazapine-induced rises in 3alpha,5alpha-tetrahydroprogesterone and 3alpha,5beta-tetrahydroprogesterone were abolished by additional lithium administration, as compared to mirtazapine monotherapy. In study 2, the mirtazapine-evoked increase in 3alpha,5alpha-tetrahydroprogesterone was reversed after additional administration of carbamazepine, presumably due to lowered mirtazapine levels after induction of cytochrome P450 enzymes. Apparently, the mood stabilizers lithium and carbamazepine do not enhance but rather reverse the increase in plasma concentrations of 3alpha-reduced neuroactive steroids in depressed patients pretreated with antidepressants such as mirtazapine.  相似文献   
96.
Oral chronic graft versus host disease (cGVHD) is common and a major cause of morbidity and loss of quality of life in long term survivors. Cyclosporine with prednisone remains the first line therapy for oral manifestations of cGVHD. However, even with routine administration of systemic agents, many patients with oral manifestations of cGVHD do not have resolution of their disease and may benefit from incorporation of local therapy. Budesonide is a highly potent steroid which has minimal systemic side effects and being used for oral cGVHD. We designed a retrospective study to compare treatment results of patients with oral cGVHD who received topical budesonide in addition to systemic therapy that consists of combined prednisone and cyclosporine (Group A, n = 12), with the treatment results of patients who were administered the same systemic therapy alone (Group B, n = 11) to determine whether budesonide mouthwash had any advantage on response rates. Three mg topical budesonide/10 ml saline was used 3-4 times a day for up to 6 months in group A. Diagnosis, clinical staging, and treatment response scoring for cGVHD were performed according to National Institutes of Health (NIH) consensus criteria. At the baseline examination, there were no statistically significant differences in terms of median oral cGVHD examination scores between two groups. After treatment, there was statistically significant decrease in median oral cGVHD examination scores compared to baseline (P < 0.001 and 0.021), and significant differences were found between two groups (P < 0.032). Overall response rate was 83% and 36% for group A and B, respectively (P = 0.036). However, no statistically significant differences were found between median pain scores of two groups before and after treatment (P = 0.740 and P = 0.091). No major systemic side effects and oral candidiasis were observed in two groups of patients. We concluded that topical budesonide might be added to systemic therapy to obtain better response rates in patients with oral cGHVD.  相似文献   
97.
98.
Advances in Alzheimer Disease (AD) research suggest that central nervous system (CNS) lipids play a key role in the pathogenesis. This role is attributed to the rich lipid content of CNS structures and the presence of blood brain barrier which disables the exchange of lipids between CNS and plasma. Among these lipids, cholesterol is a unique molecule provided mainly by its de novo synthesis in the CNS. Special apolipoproteins used for its efficient recycling within the CNS and special oxysterols formed that are specific to brain all contribute to the unique properties of the molecule. Above all, the presence of cholesterol in the membrane enables it to function as a regulator of a number of protein related processes such as the beta-amyloid precursor protein cleavage. Cholesterol reducing agents such as statins are recently proposed to have a protective role in AD. This review will focus on the role of cholesterol metabolism and genetics in AD. Current literature investigating the relationship between cholesterol and AD will be evaluated from the pathophysiological perspective. Genetic studies concerning proteins which are involved in the CNS cholesterol metabolism will also be summarized in the hope that genomics may stimulate further studies and thus contribute to a more clear understanding of the molecular mechanisms in the pathophysiology of AD.  相似文献   
99.
OBJECTIVE: Myocardial ischaemia in cardiac syndrome X (CSX) is believed to be due to microvascular dysfunction. Increased oxidative stress is one of the suspected mechanisms of microvascular dysfunction. The aim of this study was to evaluate the oxidative status in patients with CSX, by determining serum paraoxonase-1 (PON 1) activity in addition to LDL-oxidation markers. METHODS AND RESULTS: This cross-sectional study consisted of patients with CSX (group I, n = 30), patients with coronary artery disease (group II, n = 31), and healthy controls (group III, n = 32). Lipid parameters, PON-1 activity, and LDL oxidation markers (conjugated-diene and thiobarbituric acid-reactive substance-TBARS) were measured. Endothelium-dependent vasodilatation was determined by brachial artery ultrasonography. There were no significant differences in serum LDL, apolipoprotein-B, baseline LDL-diene, and LDL-TBARS levels between groups. There were no differences in both apolipoprotein-A1 and HDL levels between group I and group III. Apolipoprotein-A1 and HDL levels were significantly lower in group II than group I patients (P < 0.001). PON-1 activity was lowest in group II patients. Average PON-1 activity in group I was in between of group II and group Ill. The percent change of LDL-diene levels after stimulation was significantly higher in group II than in groups I and III (P = 0.005 and P = 0.02, respectively). The percent change of LDL-TBARS levels was lowest in group I (P = 0.03). There was a moderate correlation between endothelium-dependent vasodilatation and PON-1 activity in group I (r = 0.43, P = 0.04). CONCLUSIONS: Enhanced oxidative stress might be one of the causes of impaired endothelial functions resulting in myocardial ischaemia and chest pain in patients with CSX. The relatively preserved HDL and apolipoprotein-A1 levels in patients with CSX might be a protective mechanism against progression of coronary microvascular dysfunction to atherosclerotic coronary artery disease.  相似文献   
100.
The aim of this study was to evaluate the impact of enuresis nocturna on quality of life of the mothers. Mothers who have a child with monosymptomatic nocturnal enuresis (n = 28) and mothers who have a child without any health problems (n = 38) were enrolled in the study. Groups were in balance for background variables (child’s age, gender, and number of siblings; mother’s age, marital status, highest year of education completed, and occupation; presence of health insurance; and type of residence). Short-Form Health Survey (SF-36) Questionnaire, the Beck Depression Inventory (BDI), and Spielberg’s State-Trait Anxiety Inventory (STAI) were applied to all mothers. The mothers of children with enuresis had significantly lower quality-of-life scores in the SF-36 for the bodily pain (p = 0.015) and role emotional (p = 0.014) subscales. We observed significant difference between groups according to BDI; mean score was higher in mothers who have a child with enuresis nocturna (p = 0.017). There was no significant difference between groups according to the STAI. Significant differences according to bodily pain and role emotional subscales of SF-36, and the BDI scores, show that the mothers were negatively affected by having a child with monosymptomatic nocturnal enuresis.  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