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   28013篇
  免费   1916篇
  国内免费   119篇
耳鼻咽喉   356篇
儿科学   581篇
妇产科学   527篇
基础医学   4133篇
口腔科学   434篇
临床医学   2549篇
内科学   6467篇
皮肤病学   500篇
神经病学   3104篇
特种医学   1033篇
外国民族医学   3篇
外科学   4657篇
综合类   150篇
一般理论   6篇
预防医学   1470篇
眼科学   451篇
药学   2026篇
中国医学   95篇
肿瘤学   1506篇
  2023年   92篇
  2022年   172篇
  2021年   446篇
  2020年   266篇
  2019年   491篇
  2018年   573篇
  2017年   442篇
  2016年   499篇
  2015年   647篇
  2014年   843篇
  2013年   1131篇
  2012年   1732篇
  2011年   1835篇
  2010年   1149篇
  2009年   1011篇
  2008年   1727篇
  2007年   1809篇
  2006年   1693篇
  2005年   1797篇
  2004年   1683篇
  2003年   1685篇
  2002年   1600篇
  2001年   493篇
  2000年   421篇
  1999年   472篇
  1998年   405篇
  1997年   359篇
  1996年   287篇
  1995年   303篇
  1994年   241篇
  1993年   247篇
  1992年   304篇
  1991年   271篇
  1990年   222篇
  1989年   242篇
  1988年   196篇
  1987年   211篇
  1986年   203篇
  1985年   167篇
  1984年   166篇
  1983年   157篇
  1982年   142篇
  1981年   124篇
  1980年   108篇
  1979年   118篇
  1978年   69篇
  1977年   92篇
  1975年   70篇
  1974年   62篇
  1973年   80篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
European Surgery - Treatment of pilonidal sinus disease (PSD) requires a tailored approach. A national guideline was published in 2014. The current status of surgical PSD therapy...  相似文献   
2.
Despite common experiences of identity damage, decline, and deterioration, many brain injury survivors succeed in reconstructing robust identities in the wake of injury. Yet, while this accomplishment greatly benefits survivors’ quality of life, little is known about how positive identity work might be facilitated or enhanced in therapeutic institutions. Drawing on data from a women’s self-help group, we argue that an egalitarian, reflective, strength-focused, and gender-segregated environment can provide female ABI (acquired brain injury) survivors with a fertile scene for identity enhancement and offer unique opportunities for collective identity development. Sociolinguistic interactional analysis revealed four types of positive identity work undertaken within the group: constructing competent selves; tempering the threat of loss and impairment; resisting infantilisation and delegitimisation; and asserting a collective gender identity. This identity work was facilitated by specific programme attributes and activities and contributed to the global project of decentring disability and destigmatising impairments and losses. We call for increased attention to identity issues in brain injury rehabilitation and argue that gender-segregated programming can provide a unique space for female survivors to construct empowering individual and collective identities after injury.  相似文献   
3.
4.
5.
6.
7.
8.
Previous studies have shown that 7,12-dimethylbenz[a]anthracene (DMBA) is cytotoxic to various murine lymphoid tissues, including the spleen, thymus, mesenteric lymph nodes (MLNs), and Peyer's patches (PPs). In the present studies, we measured the amount of covalent binding of [3H]DMBA to lymphoid and nonlymphoid tissues and correlated these findings with the overall levels of [3H]DMBA (and derived substances) present in various tissues following a single oral administration to mice. Results show that [3H]DMBA was taken up relatively rapidly from the GI tract and that it was nearly completely eliminated within 24 hr via the feces. Peak plasma levels were obtained approximately 6 hr after gavage, and most organs (including brain, heart, liver, lung, kidney, spleen, and thymus) achieved their peak level of DMBA at this time. Maximal concentrations of DMBA were detected in gut-associated lymphoid tissues (i.e., PPs and MLNs) at 4 hr, during which time covalent binding of [3H]DMBA was also maximal. The time course for covalent binding was different in the liver, lung, thymus, and spleen, peaking at 6-12 hr. The amount of covalent binding of [3H]DMBA and derived metabolites in the spleen was more than twice that seen in the other tissues examined. Since the spleen has previously been found to be less sensitive to DNA fragmentation induced by DMBA than the PPs, these results suggest that covalent binding may not be the primary determinant of lymphotoxicity in these organs.  相似文献   
9.
The efficiency of Eurocollins or modified University of Wisconsin (UW) solution (MUW) in preserving rat livers was compared. After cold storage with one of the solutions, the livers were transplanted or perfused by collagenase for isolation of hepatocytes. Five of the 6 rats receiving a graft preserved with MUW versus none of the 6 rat receiving a graft preserved with Eurocollins solution survived 24 h or more. A significantly greater number of hepatocytes were isolated from livers preserved with MUW than from livers preserved with Eurocollins solution. This suggests a better reperfusion of MUW-preserved livers by collagenase resulting from less endothelial injury. LDH release by cultured hepatocytes, ketone body production and stimulation by glucagon were not significantly different between the two groups. These results confirm the superiority of MUW solution over Eurocollins in preserving liver grafts. They suggest that the advantage of MUW solution results from better protection of vascular endothelium rather than of hepatocytes.  相似文献   
10.
The authors present 50 cases of cervical spondylotic myelopathy treated by anterior or posterior approach. To assess the severity of the pre- and postoperative neurological symptoms, they define an original ten-point classification scale taking into account gait and urinary disturbance, ability to manipulate objects and pain. With C2-C7 laminectomy, 60% of the patients are improved, essentially for walk. A few cases only (14%) are upgraded for upper limbs function. The authors conclude that this surgical treatment should be applied only when there is a multi-level narrowed canal and predominant lower limbs deficits. The efficacy of the anterior approach depends on complete removal of osteophytes. In cases with complete osteophytectomy, this surgical treatment can improve both the upper and lower limbs function and 77.8% good results are obtained. In a few cases it may be necessary to use both approach successively. Discriminant analysis applied to 12 factors shows that pre-operative scores of upper and lower limbs and sagittal diameter of spinal canal are the most important factors for neurological prognosis.  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