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   1315篇
  免费   106篇
  国内免费   20篇
儿科学   86篇
妇产科学   14篇
基础医学   136篇
口腔科学   63篇
临床医学   128篇
内科学   235篇
皮肤病学   48篇
神经病学   69篇
特种医学   243篇
外科学   125篇
综合类   31篇
预防医学   78篇
眼科学   17篇
药学   81篇
  1篇
肿瘤学   86篇
  2023年   4篇
  2022年   4篇
  2021年   11篇
  2020年   11篇
  2019年   9篇
  2018年   15篇
  2017年   7篇
  2016年   17篇
  2015年   34篇
  2014年   28篇
  2013年   51篇
  2012年   40篇
  2011年   35篇
  2010年   62篇
  2009年   56篇
  2008年   40篇
  2007年   43篇
  2006年   38篇
  2005年   47篇
  2004年   36篇
  2003年   39篇
  2002年   28篇
  2001年   21篇
  2000年   11篇
  1999年   30篇
  1998年   81篇
  1997年   77篇
  1996年   70篇
  1995年   55篇
  1994年   38篇
  1993年   51篇
  1992年   11篇
  1991年   26篇
  1990年   17篇
  1989年   43篇
  1988年   36篇
  1987年   27篇
  1986年   22篇
  1985年   27篇
  1984年   12篇
  1983年   12篇
  1982年   14篇
  1981年   15篇
  1980年   19篇
  1979年   10篇
  1978年   14篇
  1977年   17篇
  1976年   12篇
  1975年   9篇
  1971年   3篇
排序方式: 共有1441条查询结果,搜索用时 15 毫秒
71.
Little objective evidence has been published to support the claim that constipation is an important contributory factor in recurrent urinary tract infection (UTI) in childhood. Using a radiological scoring system, two observers assessed faecal loading from abdominal radiographs of children with proved UTIs. There was a significant increase in the degree of faecal loading in children with UTI when compared with controls (r = 0.237). This difference was mainly accounted for by girls with recurrent (greater than five) UTIs. This study confirms an association between recurrent UTI and faecal loading. Further studies are needed to establish if there is a causal relationship and benefits from treatment.  相似文献   
72.

Background  

The Licensing Act 2003 (The Act) was implemented on the 24th November 2005 across England and Wales. The Act allowed more flexible and longer opening hours for licensed premises. We investigated the effect of The Act on alcohol related attendances to an inner city emergency department in Birmingham, UK.  相似文献   
73.
Extralobar pulmonary sequestration was found in a newborn premature infait that presented with non-immune hydrops fetalis, massive bilateral hydrothorax and polyhydramnios in utero. The baby died of severe respiratory insufficiency 15 h after birth. Postmortem examination revealed distended lymphatic vessels in the sequestered lung tissue probably due to impeded lymph drainage. We suggest that not extralobar pulmonary sequestration itself but a subsequent massive unilateral hydrothorax due to severe obstruction of lymph drainage was the cause of the non-immune hydrops fetalis, pulmonary hypoplasia and polyhydramnios. If these symptoms are diagnosed before delivery, a search for extralobar pulmonary sequestration is indicated.  相似文献   
74.
75.
To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.  相似文献   
76.
It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.  相似文献   
77.
78.
79.
80.
Cohen IT  Joffe D  Hummer K  Soluri A 《Anesthesia and analgesia》2005,101(1):59-63, table of contents
Postoperative nausea and vomiting (PONV), a major complication in children, is responsive to IV and oral ondansetron. Because these routes are not always available, we studied the acceptability and efficacy of ondansetron oral disintegrating tablets (ODT). In this double-blind, randomized, placebo-controlled study, 62 patients undergoing adenotonsillectomy, aged 5 to 11 years, preoperatively received ODT (4 mg) or placebo. Patients assessed the medication for taste and sensation. Anesthesia was induced with sevoflurane, maintained with desflurane, and supplemented with fentanyl 2.5 microg/kg and dexamethasone 0.5 mg/kg (maximum dose, 12 mg). An observer blinded to treatment evaluated patients for pain, agitation, and PONV. Postoperative treatment consisted of fentanyl 1 microg/kg for pain and agitation and metoclopramide 0.15 mg/kg (maximum dose, 10 mg) for PONV. There were no significant differences between study groups with regard to age, weight, recovery time, agitation, or pain. Approximately 90% of the subjects found the ODT to taste good. No subject rejected the study medication, but the ondansetron-containing tablets were found to be less palatable than the placebo. The incidence of vomiting was significantly less in the ondansetron-medicated group.  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