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   1370436篇
  免费   102608篇
  国内免费   4386篇
耳鼻咽喉   17235篇
儿科学   44756篇
妇产科学   36839篇
基础医学   202059篇
口腔科学   36398篇
临床医学   133255篇
内科学   265967篇
皮肤病学   26910篇
神经病学   115212篇
特种医学   49593篇
外国民族医学   366篇
外科学   190013篇
综合类   29108篇
现状与发展   1篇
一般理论   542篇
预防医学   117138篇
眼科学   29923篇
药学   100618篇
  6篇
中国医学   3198篇
肿瘤学   78293篇
  2021年   12220篇
  2019年   12677篇
  2018年   17594篇
  2017年   13193篇
  2016年   14232篇
  2015年   16214篇
  2014年   22244篇
  2013年   33793篇
  2012年   47124篇
  2011年   49773篇
  2010年   28652篇
  2009年   26354篇
  2008年   45068篇
  2007年   47408篇
  2006年   47406篇
  2005年   45730篇
  2004年   43606篇
  2003年   41202篇
  2002年   39902篇
  2001年   61068篇
  2000年   62695篇
  1999年   52491篇
  1998年   14864篇
  1997年   13540篇
  1996年   13302篇
  1995年   12655篇
  1994年   11777篇
  1993年   11063篇
  1992年   41697篇
  1991年   40888篇
  1990年   39534篇
  1989年   37430篇
  1988年   34660篇
  1987年   33778篇
  1986年   32207篇
  1985年   30708篇
  1984年   23104篇
  1983年   19670篇
  1982年   11855篇
  1979年   20837篇
  1978年   14844篇
  1977年   12093篇
  1976年   11896篇
  1975年   12124篇
  1974年   14816篇
  1973年   14494篇
  1972年   13375篇
  1971年   12434篇
  1970年   11495篇
  1969年   10420篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
Resection of the adrenal glands precludes participation in many immunotherapy protocols for metastatic renal cell carcinoma. We performed radical nephrectomy with adrenalectomy and contralateral partial adrenalectomy, including adrenal vein ligation for a 4 cm. hilar metastasis without perioperative complications or local recurrence after 30 months. Adrenal function, measured by cosyntropin stimulation tests 6 weeks and 10 months postoperatively, was normal. Partial adrenalectomy with preservation of adrenal function is possible.  相似文献   
995.
996.
Irritability is often a problem for patients with Post-Traumatic Stress Disorder (PTSD). We describe two cases that illustrate the use of lithium in the treatment of veterans with PTSD who complained of serious problems with irritability or angry outbursts. These cases are discussed in the context of evidence that lithium may be useful in other patients with disorders of impulse control. The evidence linking disorders of anger and impulse control to a dysregulation in neurotransmitter regulation, particularly in serotonergic pathways, supports a psychopharmacologic approach to treatment. These findings should lead to further study of the role of lithium in the treatment of this symptom complex in patients with PTSD.  相似文献   
997.
Hormone replacement therapy is the optimal therapeutic choice for postmenopausal syndrome. While low doses of estrogens (0.3 mg/day of conjugated estrogens) can counteract neurovegetative menopausal symptoms, higher doses (0.625 mg/day of conjugated estrogens) are required to prevent bone loss in postmenopausal women. Experimental and clinical studies have shown that ipriflavone, a non-hormonal isoflavone derivative, is effective in the prevention and treatment of postmenopausal osteoporosis. The aim of the present investigation was to evaluate the efficacy and toler-ability of ipriflavone and very low doses of equine conjugated estrogens on bone loss in early postmenopausal women. Eighty-three healthy postmenopausal women (50.3±0.7 years) were enrolled for this 1-year multicenter study. All subjects were randomly allocated to receive: double placebo (n=24; group A), placebo plus conjugated equine estrogens 0.30 mg/day (n=31; group B) or conjugated equine estrogens 0.30 mg/day plus oral ipriflavone 200 mg tris in die at meals (n=28; group C), according to a double-masked design. Among women who completed the treatment period (valid completers), those of group A showed a progressive decrease in forearm bone density (FBD; measured by dual photon absorptiometry) that reached 1.7% after 12 months. The women in group B maintained their FBD in the first 6 months of treatment but, at the end of the study, showed a bone loss of 1.4% compared with basal values. By contrast, women in group C showed a significant increase in FBD after 1 year of treatment (+5.6%;p<0.01). Bothvalid completers andintention to treat analyses revealed a significant difference (p<0.05) between group A and group C over the study period. None of the treatments produced significant changes of biochemical markers of bone turnover, while hot flushes and other climacteric symptoms were significantly reduced after the sixth month of treatment in women receiving estrogens. Adverse events were generally mild, and did not differ among the groups. The results of this study suggest that low doses of estrogens combined with ipriflavone could represent a new therapeutic approach to the treatment of the postmenopausal syndrome.  相似文献   
998.
The discovery of an inducible isoform of cyclooxygenase (COX-2) requires a refinement of the theory that inhibition of cyclooxygenase activity is responsible for both therapeutic and side-effects of nonsteroidal anti-inflammatory drugs (NSAIDs). Pharmacological results with developmental compounds suggest that COX-2 is the relevant target for the therapeutic (i.e. anti-inflammatory) effects of NSAIDs, whereas gastric and renal side-effects are related to inhibition of constitutive COX-1. However a role of COX-1 in inflammation cannot be excluded. Furthermore, more research effort is needed to investigate the functional relevance of COX-2 in normal tissue.  相似文献   
999.
Management of hypothalamic gliomas in children: an analysis of 33 cases   总被引:2,自引:0,他引:2  
L A Rodriguez  M S Edwards  V A Levin 《Neurosurgery》1990,26(2):242-6; discussion 246-7
The cases of 33 children with hypothalamic-chiasmatic gliomas are reviewed. Radiation therapy produced clinical or radiographic improvement in 11 (46%) of 24 patients. Progression was documented in 18 patients (54%). Overall, the median time to tumor progression was 60 months; it was 70 months in patients who received radiation therapy and 30 months in those who did not (P less than 0.05). Chemotherapy, either given initially or at the time of progression, caused the tumor to respond or to stabilize in 10 patients. Partial resection of the tumor led to improvement in 3 of 12 patients, obviating the need for a shunt in 2 of them; there were no deaths and postoperative morbidity was transient and minimal (diabetes insipidus, intraventricular hemorrhage, and left hemiparesis in one patient each). The 5- and 10-year survival probabilities were 93 and 74%, respectively. Patients with neurofibromatosis had a better prognosis.  相似文献   
1000.
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