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   238篇
  免费   11篇
耳鼻咽喉   3篇
儿科学   20篇
妇产科学   7篇
基础医学   21篇
口腔科学   1篇
临床医学   8篇
内科学   108篇
皮肤病学   1篇
神经病学   10篇
特种医学   4篇
外科学   26篇
综合类   3篇
预防医学   15篇
眼科学   2篇
药学   17篇
中国医学   2篇
肿瘤学   1篇
  2023年   6篇
  2022年   3篇
  2021年   7篇
  2020年   3篇
  2019年   6篇
  2018年   5篇
  2017年   4篇
  2016年   4篇
  2015年   2篇
  2014年   5篇
  2013年   12篇
  2012年   13篇
  2011年   8篇
  2010年   11篇
  2009年   9篇
  2008年   9篇
  2007年   17篇
  2006年   19篇
  2005年   19篇
  2004年   20篇
  2003年   15篇
  2002年   9篇
  2001年   3篇
  2000年   4篇
  1999年   10篇
  1998年   2篇
  1997年   3篇
  1995年   2篇
  1994年   2篇
  1993年   2篇
  1992年   4篇
  1991年   2篇
  1990年   3篇
  1989年   2篇
  1988年   4篇
排序方式: 共有249条查询结果,搜索用时 15 毫秒
1.
2.
3.
Prevalence of childhood asthma and allergic diseases in Ankara, Turkey   总被引:2,自引:1,他引:2  
Kalyoncu AF, Selçuk ZT, Karakoca Y, Emri AS, Çöplü L, Şahin AA, Bariş YI. Prevalence of childhood asthma and allergic diseases in Ankara, Turkey.
The first epidemiologic survey of the prevalence of childhood asthma and other allergic disease in Ankara, Turkey, was done in May 1992. A questionnaire on factors influencing the atopic status and allergic symptoms was distributed to parents of 1226 children aged 6-12 years. In this questionnaire, parents were asked to give information about physician-diagnosed asthma and atopic dermatitis (AD), and self-reported wheezing and rhinoconjunctivitis (perennial or seasonal). The overall response rate was 85 % and included 502 boys (48.5%) and 534 girls (51.5%). The lifetime prevalences of asthma, wheezing, rhinoconjunctivitis, and AD were 17.4%, 23.3%, 28%, and 6.1%, respectively, and the reported prevalences for the last 12 months were 8.3%, 11.9%, 15.4%, and 4%, respectively. Asthma and other allergic disease had been recognized in 23.2% of the children during the last year; in half of these, more than one disease was present. Eight percent of the families kept pet animals; 95.4% of children had been breast-fed, of whom 61% for more than 6 months; and at least one person smoked at home in the case of 73.9% of children. Some health insurance was available to 72.8% of the families. Cumulative prevalences of wheezing, rhinoconjunctivitis, and AD were significantly associated with the presence of pets, passive smoking at home, and absence of health insurance. The prevalence of asthma was not affected by any of these factors except atopic family history. In conclusion, asthma and other allergic diseases constitute a major health problem for schoolchildren in Ankara.  相似文献   
4.
The effects of thimerosal, a sulfhydryl oxidizing agent on nitrergic, endothelium-dependent and -independent relaxations were investigated to examine the possibility that the nitrergic neurotransmitter and endothelium-derived relaxing factor (EDRF) could be S-nitrosothiol or free nitric oxide (NO) in the isolated mouse corpus cavernosum. Thimerosal (5 x 10(-6)-2 x 10(-5) M) inhibited or almost abolished electrical field stimulation--(EFS, 30V, 0.5 ms, 15 sec, 1, 2, 4, 8, 16 Hz), acetylcholine--(ACh, 5 x 10(-8)-1.25 x 10(-6) M), glyceryl trinitrate--(GTN, 3 x 10(-7)-3 x 10(-6) M), and S-nitrosoglutathione--(GSNO, 5 x 10(-6)-1.25 x 10(-4) M) induced relaxations. Thiomerosal inhibition seems to be specific to L-arginine NO pathways since it had no effect on acidified sodium nitrite--(10(-4)-5 x 10(-4) M), photoactivated sodium nitrite--(2 x 10(-4) M), isoprenaline--(10(-6) M), or papaverine--(10(-4) M) elicited relaxations. Moreover, the inhibitory effect of thimerosal on the nitrergic, ACh- or GTN-induced relaxations were partly reversed by sulfhydryl-containing compounds, L-cysteine (10(-3) M), dithiothreitol (10(-3) M), or glutathione (10(-3) M). However L-methionine (10(-3) M), which contains a methyl group on the sulphur atom, failed to restore the thimerosal inhibition. Thimerosal did not change the contraction produced by 10(-4) M NG-nitro-L-arginine methyl ester. These findings indicate that the nitrergic neurotransmitter as well as EDRF may not be free NO but NO-transferring molecules, probably S-nitrosothiols, in the mouse corpus cavernosum.  相似文献   
5.
1. The aim of this study was to investigate the effect of sertraline, a selective serotonin re-uptake inhibitor, on contractile responses to noradrenaline (NA), KCl, serotonin (5-HT) and electrical field stimulation of rat isolated vas deferens. 2. Pre-treatment with 10(-4) M sertraline showed inhibitory effects on responses to NA, KCl, 5-HT and electrical field stimulation, while pre-treatment with 10(-6) and 10(-5) M sertraline caused potentiation of responses to NA (10(-7) and 10(-6) M). 3. A voltage-dependent calcium channel activator, Bay K 8644, restored the inhibited responses when sertraline was washed out of the organ bath, although restoration could not be seen when sertraline was not removed. 4. The inhibition of the contractile responses by sertraline pre-treatment may be via a mechanism through calcium channels which is additional to the selective serotonin re-uptake inhibitory effect of sertraline.  相似文献   
6.
The aim of the present study is to evaluate whether paroxetine (a selective serotonin re-uptake inhibitor) can modify the contractile responses of isolated vas deferens. Some contractile agents, potassium chloride (KCl), adenosine 5'-triphosphate (ATP), noradrenaline (NA), and electrical field stimulation (EFS) caused contractions both in epididymal and prostatic portions of vas deferens. Paroxetine (PX) in concentrations 10(-7) and 10(-6)M potentiated the contractions to KCl and ATP only in epididymal portion but in higher concentrations (10(-5) and 10(-4)M) inhibited the responses in both portions. NA responses were inhibited by PX in all concentrations used, both in prostatic and epididymal portions. Prazosin (PR), an alpha adrenergic receptor blocking agent, inhibited PX-induced potentiation observed for higher concentrations of KCl. PR also inhibited PX-induced potentiation on the responses to ATP in epididymal portion. Pretreatment with PX (10(-7) to 10(-6)M) increased the contractions to EFS but in 10(-5) and 10(-4)M concentrations inhibited them. Even though the preparations were washed out, the inhibited responses of contractile agents could not be restored. After a washout period for PX, when Bay K 8644 (calcium channel activator) was added to the bath medium, the contractile responses to KCl were partially restored. In calcium-free medium, KCl caused contractions in concentrations higher than 80 mM with lower amplitudes which were not affected by PX. Reserpinization did not change the inhibitory pattern of PX's effect on exogenously applied NA in all concentrations tested. In reserpinized rats, the potentiation caused by PX in exogenously applied ATP responses was not observed. In conclusion, we can say that PX has two different effects: inhibition and potentiation of contractions to various agonists. The inhibitory effect of the drug can be explained by a calcium channel blocking activity. The potentiating effect of the drug is mainly related to its presynaptic action, such as NA re-uptake inhibitory effect.  相似文献   
7.
Perioperative spasm of internal mammary artery is a common experience in coronary artery bypass grafting. Many techniques were described of harvesting the internal mammary artery to prevent vasospasm. We investigated the comparison of the contracting and relaxing responses of human internal mammary artery grafts harvested by two different methods. Patients were divided into two groups depending on the harvesting technique. In the first and second groups arteries were harvested by classical and carbon dioxide insufflation techniques, respectively. In both groups, endothelial function of arteries was assessed by precontracting the rings with phenylephrine (10(-5)M) and dilatating them by cumulative acetylcholine (10(-8) to 10(-5)M) concentrations. Cumulative concentration-response curves for phenylephrine (10(-8) to 10(-4)M), noradrenaline (10(-9) to 10(-4)M), and 5-hydroxytryptamine (10(-9) to 10(-4)M) were obtained in all groups. Endothelial integrity of arteries were histopathologically evaluated. In both groups, acetylcholine caused concentration-dependent relaxations in rings precontracted with phenylephrine (10(-5)M). In arteries harvested by carbon dioxide insufflation technique, acetylcholine caused significantly higher relaxations compared to the rings obtained by classical technique (p<0.05). In all rings of study groups, phenylephrine, noradrenaline and 5-hydroxytryptamine caused concentration-dependent contractions. There was not any significant difference in concentration-dependent responses of these contracting pharmacological agents between the groups. Histopathological evaluation revealed no major arterial damage in both groups. Carbon dioxide insufflation technique does seem not only to protect the integrity of the endothelium and the whole vessel, but also prevent the possible vasospasm of the internal mammary artery segments.  相似文献   
8.
Background Acne vulgaris is a common disease affecting adolescents. There is not comprehensive data on acne prevalence in the Central Anatolia Region in particular. Etiology of acne is not clarified yet. Acne might be related to environmental factors. There is increasing evidence supporting acne and diet relationship. Objectives The aim of the study was to determine the acne prevalence in adolescents in the city of Eskisehir, located in the Central Anatolia, Turkey in addition to evaluate factors affecting acne and its relationship with dietary habits. Methods A cross‐sectional study was conducted on 2300 participants aged 13–18 years. The participants were asked to complete a questionnaire form consisting information about acne and a questionnaire form consisting information about dietary habits (The Adolescent Food Habits Checklist). In addition an objective evaluation of acne was determined. Results The mean age of students with acne was 15.10 ± 1.53. The current acne prevalence was 60.7%. Although 21% of the participants had severe acne (grade 3–4) and 25% developed sequelaes, only 11.5% of all participants consulted a doctor. The participants without acne had healthier dietary habits than participants with acne (P < 0.05). Frequent fat intake (OR = 1.39, 95% CI: 1.06–1.82), frequent sugar intake (OR = 1.30, 95% CI: 1.05–1.60), frequent eating sausages, burgers (OR = 1.24, 95% CI: 1.03–1.48), frequent eating pastries, cakes (OR = 1.20, 95% CI: 1.01–1.43) were associated with increased risk for acne. Conclusions Acne prevalence is high among adolescents in Eskisehir but the rate of consulting doctor is low. Increasing public awareness is critical for convincing adolescents to seek medical help earlier. Acne was related with dietary habits. Fat, sugar and fast food consumption is found to be positively correlated with acne prevalence.  相似文献   
9.
Clinical Rheumatology - Immunoglobulin A vasculitis (IgAV) is the most common form of childhood systemic vasculitis. It is mostly self-limiting and characterized by skin, joint, gastrointestinal...  相似文献   
10.
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