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   350篇
  免费   23篇
  国内免费   29篇
耳鼻咽喉   3篇
儿科学   22篇
妇产科学   3篇
基础医学   34篇
口腔科学   18篇
临床医学   61篇
内科学   92篇
皮肤病学   8篇
神经病学   12篇
特种医学   28篇
外科学   54篇
综合类   19篇
一般理论   1篇
预防医学   14篇
药学   15篇
中国医学   2篇
肿瘤学   16篇
  2022年   4篇
  2021年   2篇
  2020年   3篇
  2019年   8篇
  2018年   5篇
  2017年   8篇
  2016年   9篇
  2015年   8篇
  2014年   13篇
  2013年   14篇
  2012年   7篇
  2011年   9篇
  2010年   14篇
  2009年   14篇
  2008年   14篇
  2007年   17篇
  2006年   8篇
  2005年   21篇
  2004年   8篇
  2003年   6篇
  2002年   10篇
  2001年   13篇
  2000年   6篇
  1999年   12篇
  1998年   21篇
  1997年   20篇
  1996年   18篇
  1995年   13篇
  1994年   14篇
  1993年   3篇
  1992年   7篇
  1991年   4篇
  1990年   4篇
  1989年   9篇
  1988年   6篇
  1987年   8篇
  1986年   12篇
  1985年   5篇
  1983年   1篇
  1982年   2篇
  1981年   2篇
  1980年   1篇
  1978年   4篇
  1977年   5篇
  1976年   4篇
  1975年   3篇
  1974年   1篇
  1973年   1篇
  1971年   1篇
排序方式: 共有402条查询结果,搜索用时 31 毫秒
101.
Successful transplantation requires the prevention of allograft rejection and, in the case of transplantation to treat autoimmune disease, the suppression of autoimmune responses. The standard immunosuppressive treatment regimen given to patients with autoimmune type 1 diabetes who have received an islet transplant results in the loss of T cells. In many other situations, the immune system responds to T cell loss through cytokine-dependant homeostatic proliferation of any remaining T cells. Here we show that T cell loss after islet transplantation in patients with autoimmune type 1 diabetes was associated with both increased serum concentrations of IL-7 and IL-15 and in vivo proliferation of memory CD45RO(+) T cells, highly enriched in autoreactive glutamic acid decarboxylase 65-specific T cell clones. Immunosuppression with FK506 and rapamycin after transplantation resulted in a chronic homeostatic expansion of T cells, which acquired effector function after immunosuppression was removed. In contrast, the cytostatic drug mycophenolate mofetil efficiently blocked homeostatic T cell expansion. We propose that the increased production of cytokines that induce homeostatic expansion could contribute to recurrent autoimmunity in transplanted patients with autoimmune disease and that therapy that prevents the expansion of autoreactive T cells will improve the outcome of islet transplantation.  相似文献   
102.
103.
104.
The case of a 42-year-old woman with prolonged migraine visual aura without headache, whose long-lasting episodes of visual aura were successfully controlled by oral sumatriptan, is reported. Effectiveness of sumatriptan was unequivocal, since, after taking sumatriptan, duration of aura would drop from 1.5 h to approximately 20 min. This case suggests that sumatriptan may cross the blood-brain barrier and block spreading depression.  相似文献   
105.
Women with recurrent abortion, primary unexplained infertility, and gestational trophoblastic neoplasia (GTN) manifest disordered human chorionic gonadotrophin (HCG) secretion. Mutations in the HCG beta/luteinizing hormone (LH) beta gene complex could cause aberrant HCG production in these disorders. The purpose of this study was to determine whether HCG beta gene deletions occur in women with recurrent abortion or primary unexplained infertility, and whether HCG beta gene duplications are present in women with GTN. DNA was extracted from 10 patients with unexplained recurrent abortion, 10 patients with unexplained primary infertility, 12 patients with GTN, three partners of women with GTN, and 30 controls. Southern blots were constructed and hybridized with DNA probes for HCG beta-5 and the LH beta gene. No gene deletions were identified in patients with recurrent abortion or primary unexplained infertility. Likewise, no gene duplications were identified in women with GTN. A previously described Mbol restriction fragment length polymorphism (RFLP) was identified in both patients and controls. A new Pstl RFLP was also characterized, but was present in patients and controls. Deletion/duplication mutations in the HCG beta/LH beta gene complex do not appear to be common causes of aberrant HCG production in humans with these disorders.   相似文献   
106.
Indium-111 labeled leukocyte imaging was compared with three-phase skeletal scintigraphy as a means of determining whether osteomyelitis was complicating diabetic osteoarthropathy. Three-phase scintigraphy demonstrated increased activity in both infected and noninfected osteopathic bone, with a sensitivity of 75% and a specificity of 56% for osteomyelitis. Leukocyte imaging had the same sensitivity but was most helpful for excluding infection (specificity, 89%) when three-phase imaging could not. Abnormal leukocyte localization was seen at the primary site of infection in all cases within 4 hours after injection. Disadvantages of leukocyte imaging included long preparation time, low count rates resulting in poor spatial resolution, and absence of bone landmarks, which made it difficult to differentiate soft tissue from bone infection.  相似文献   
107.
Objective : To determine the genotype of patients attending the cystic fibrosis clinic at John Hunter Hospital, Newcastle, Australia.
Methodology : Seventy-five of the 76 patients attending the clinic over a 6 month period had blood collected for genetic analysis of 17 of the cystic fibrosis (CF) gene mutations.
Results : Sixty-one per cent of the patients were homozygous for the ΔF508 mutation and all except one child had at least one ΔF508 mutation.
Discussion : Nearly 80% of the CF genes were the ΔF508 mutation. This prevalence suggests that the obligatory false negative rate of a newborn screening programme for CF based on a combination of immunoreactive trypsin and the ΔF508 gene may be as low as 4-5%.  相似文献   
108.
Chan  FK  Ching  JY  Hung  LC  齐文安 《英国医学杂志》2005,8(6):372-373
问题:在有阿司匹林诱发溃疡出血史的患者中,用氯毗格雷预防溃疡出血复发,是否不次于小剂量阿司匹林加埃索美拉唑?[编者按]  相似文献   
109.
110.
The coronavirus disease 2019 (COVID-19) lockdown dramatically changed people’s lifestyles. Diet, physical activity, and the PNPLA3 gene are known risk factors for non-alcoholic fatty liver disease (NAFLD). Aim: To evaluate changes in metabolic and hepatic disease in NAFLD patients after the COVID-19 lockdown. Three hundred and fifty seven NAFLD patients were enrolled, all previously instructed to follow a Mediterranean diet (MD). Anthropometric, metabolic, and laboratory data were collected before the COVID-19 lockdown in Italy and 6 months apart, along with ultrasound (US) steatosis grading and information about adherence to MD and physical activity (PA). In 188 patients, PNPLA3 genotyping was performed. After the lockdown, 48% of patients gained weight, while 16% had a worsened steatosis grade. Weight gain was associated with poor adherence to MD (p = 0.005), reduced PA (p = 0.03), and increased prevalence of PNPLA3 GG (p = 0.04). At multivariate analysis (corrected for age, sex, MD, PA, and PNPLA3 GG), only PNPLA3 remained independently associated with weight gain (p = 0.04), which was also associated with worsened glycemia (p = 0.002) and transaminases (p = 0.02). During lockdown, due to a dramatic change in lifestyles, half of our cohort of NAFLD patients gained weight, with a worsening of metabolic and hepatologic features. Interestingly, the PNPLA3 GG genotype nullified the effect of lifestyle and emerged as an independent risk factor for weight gain, opening new perspectives in NAFLD patient care.  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