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   1080篇
  免费   55篇
  国内免费   6篇
耳鼻咽喉   12篇
儿科学   45篇
妇产科学   13篇
基础医学   165篇
口腔科学   7篇
临床医学   80篇
内科学   229篇
皮肤病学   4篇
神经病学   124篇
特种医学   24篇
外科学   197篇
综合类   3篇
预防医学   88篇
眼科学   9篇
药学   72篇
肿瘤学   69篇
  2021年   5篇
  2020年   7篇
  2019年   9篇
  2018年   8篇
  2017年   12篇
  2016年   7篇
  2015年   13篇
  2014年   18篇
  2013年   50篇
  2012年   54篇
  2011年   42篇
  2010年   31篇
  2009年   40篇
  2008年   76篇
  2007年   69篇
  2006年   81篇
  2005年   83篇
  2004年   79篇
  2003年   73篇
  2002年   73篇
  2001年   27篇
  2000年   11篇
  1999年   26篇
  1998年   19篇
  1997年   13篇
  1996年   13篇
  1995年   10篇
  1994年   9篇
  1993年   15篇
  1992年   10篇
  1991年   5篇
  1990年   12篇
  1989年   9篇
  1988年   8篇
  1987年   7篇
  1986年   5篇
  1985年   9篇
  1984年   10篇
  1983年   7篇
  1982年   7篇
  1981年   12篇
  1980年   4篇
  1979年   9篇
  1978年   9篇
  1976年   7篇
  1975年   4篇
  1973年   4篇
  1971年   4篇
  1967年   3篇
  1965年   3篇
排序方式: 共有1141条查询结果,搜索用时 17 毫秒
991.
992.
Few studies have investigated the relationship of temperament and character, as conceptualized in the Temperament and Character Inventory-Revised (TCI-R), to symptoms of depression and anxiety in the general population. In this study a random sample of subjects (20 to 70 years), in two Finnish cities, were surveyed with the TCI-R, Beck Depression and Anxiety Inventories, plus questions related to diagnosed lifetime mental disorders, health care use for psychiatric reasons during the past 12 months, and history of mental disorders in first-degree relatives. Altogether 347 subjects (38.6%) responded. Of the TCI-R dimensions, Harm Avoidance correlated with symptoms of depression (r(s)=0.555, p<0.001), anxiety (r(s)=0.560, p<0.001), self-reported lifetime mental disorder (r(s)=0.272, p<0.001), health care use for psychiatric reason during the past 12 months (r(s)=0.241, p<0.001) and family history of mental disorder (r(s)=0.202, p<0.001). Self-directedness correlated negatively with symptoms of depression (r(s)=-0.495, p<0.001), anxiety (r(s)=-0.458, p<0.001), lifetime mental disorder (r(s)=0.225, p<0.001) and health care use (r(s)=-0.135, p=0.013). Overall, Harm Avoidance and Self-directedness seem to associate moderately with depressive and anxiety symptoms, and somewhat predict self-reported use of health services for psychiatric reasons, and lifetime mental disorder. High harm avoidance may associate with a family history of mental disorder.  相似文献   
993.
994.
We treated 21 aggressive and malignant bone tumors by wide resection and replacement with deep-frozen osteoarticular and segmental (intercalary and block) allografts. Radiologic and histologic studies showed a gradual accretion of new bone on the graft trabeculae, sometimes with total creeping substitution. Substantial resorption of grafted condylar bone occurred in 3 of 14 cases. One of them ended with arthrodesis; in the other 2 the result after augmentation autografts was fair. Radiographically, a gradual joint surface destruction was observed in all the osteoarticular grafts after 5 years, not correlating with joint function, however. Biopsies showed some cartilage regeneration. Each patient underwent, on an average, two operations. Function after osteoarticular grafts at 3-16 years was excellent in 1 case, good in 4, fair in 6, and poor in 1 case; 2 cases were too recent for evaluation. Function 3-12 years after segmental grafts was excellent in 3 cases and poor in 3 cases (1 amputation due to nonunion, 1 amputation due to recurrence, and 1 prosthetic replacement due to recurrence); 1 case was too recent for evaluation. We conclude that an allograft is an acceptable alternative in the reconstruction of large tumor defects. However, it still presents unsolved immunologic and preservation problems, which make the prognosis guarded.  相似文献   
995.
996.
1H and13C NMR chemical shifts were determined from the NMR spectra of low concentration solutions of T-2 toxin, T-2 triol, HT-2 toxin, diacetoxyscirpenol, and neosolaniol. Isomerization of neosolaniol was observed to occur in chloroform solution. 1D and 2D1H and13C NMR techniques were used in order to determine the structure of the isomerization product, finally identified as 4,8-diacetoxy-3, 15-dihydroxy-12,13-epoxytrichothec-9-ene.  相似文献   
997.
Summary A double-blind cross-over comparison of a new 2-sympathomimetic bronchodilator, clenbuterol, with salbutamol and placebo has been made during a 24 day period of out-patient treatment of 19 adults with moderately severe asthma. Oral clenbuterol (10 µg 3 times a day) and salbutamol (4 mg 3 times a day) were equally and significantly (p<0.001) more effective than placebo, when daily records of peak expiratory flow or use of isoprenaline inhalations were the criteria of activity. Daily records of symptoms according to a questionnaire also suggested relief of the subjective effects of asthma during treatment with both active drugs (p<0.01).  相似文献   
998.
Food antigens and enteroviruses are possible triggers of type 1 diabetes. Because permeability of the intestinal epithelium may facilitate contact of these antigens with the mucosal immune system, we set out to study intestinal permeability in patients with type 1 diabetes. Children with type 1 diabetes (n = 26, mean age 12 years, mean duration of disease 4 years) and 24 healthy age-matched control children were given mannitol and lactulose orally, and their intestinal permeability was measured as a percentage of this dose recovered in urine. Patients with type 1 diabetes did not differ in their permeability to lactulose, nor was their lactulose/mannitol ratio any different from that of controls. However, patients with type 1 diabetes who had the HLA-DQB 1*02 allele and, therefore, a higher risk for celiac disease (CD) absorbed significantly more mannitol (mean + 95% CI): 17.7% (15.2-20.2) than did those negative for this allele: 12.3% (8.2-16.4), p = 0.04. Their lactulose permeability was also higher: 0.30 (0.16-0.44) and 0.09% (0-0.18), respectively, p = 0.02. Although the differences in permeability reach statistical significance, there was still much overlap between the two groups in terms of actual laboratory values. The higher permeability of patients with the HLA-DQB1*02 allele suggests that these patients may be more prone to develop abnormal immune responses to food antigens.  相似文献   
999.
Summary Procaterol is a new, potent, long-acting beta-2-adrenergic bronchodilator. The magnitude and duration of the immediate bronchodilatation produced by inhaled procaterol aerosol have been compared with those produced by inhaled salbutamol aerosol in 20 asthmatic patients. Patients inhaled two puffs of procaterol (20 g) or two puffs of salbutamol (200 g) and PEF, FVC and FEV1 were measured after 5, 15, 30, 60, 120 and 180 min.The changes in mean PEF, FEV1 and FVC values were greater after procaterol than salbutamol, but the difference in bronchodilatation was not significant. The response to rimiterol after 180 min was greater in the salbutamol group. The increases in heart rate and systolic blood pressure were slightly higher after procaterol. Eleven patients reported adverse effects; 5 after procaterol, 3 after salbutamol, and 3 after both drugs. Thus, procaterol was a potent bronchodilator when inhaled as a single dose of 20 g, but it did not appear to be an ultra long-acting preparation.  相似文献   
1000.
The objective of this study was to assess the value of lower limb revascularization and free flap transfer (LLR-FFT) in the management of critical leg ischemia and major tissue loss. A total of 29 consecutive patients with critically ischemic leg and major tissue loss underwent 24 simultaneous and 6 staged LLR-FFT procedures. The main outcome measures were bypass graft patency, free flap viability, leg salvage, patients alive with salvaged leg, and survival. At the 2-year follow-up, the bypass graft patency rate was 85%, secondary free flap viability rate was 82%, and 82% of patients achieved leg salvage and were ambulant. If the success was defined as patients being alive with a salvaged leg, the corresponding rate was 80%. Three patients achieved long-term primary patency and leg salvage despite free flap failure, which occurred during the 30-day postoperative period. Lower extremity revascularization plus free flap coverage of large ischemic lesions is valuable in achieving long-term leg salvage. Because revascularization and conventional management of major tissue loss alone can be effective in the management of a small number of cases, staged LLR-FFT is indicated, when appropriate, for better selection of patients undergoing such an aggressive and demanding 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