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   412537篇
  免费   22088篇
  国内免费   14353篇
耳鼻咽喉   3358篇
儿科学   9560篇
妇产科学   7853篇
基础医学   44281篇
口腔科学   5763篇
临床医学   43169篇
内科学   69141篇
皮肤病学   3497篇
神经病学   29548篇
特种医学   17412篇
外国民族医学   102篇
外科学   54673篇
综合类   36709篇
现状与发展   53篇
一般理论   45篇
预防医学   32648篇
眼科学   9367篇
药学   33557篇
  183篇
中国医学   11767篇
肿瘤学   36292篇
  2024年   645篇
  2023年   3212篇
  2022年   7679篇
  2021年   11656篇
  2020年   8580篇
  2019年   7724篇
  2018年   29299篇
  2017年   23926篇
  2016年   25673篇
  2015年   11103篇
  2014年   13709篇
  2013年   12812篇
  2012年   24443篇
  2011年   39744篇
  2010年   30093篇
  2009年   20656篇
  2008年   31862篇
  2007年   34085篇
  2006年   12890篇
  2005年   14571篇
  2004年   11849篇
  2003年   11857篇
  2002年   9044篇
  2001年   6270篇
  2000年   6533篇
  1999年   6586篇
  1998年   3851篇
  1997年   3870篇
  1996年   2877篇
  1995年   2691篇
  1994年   2332篇
  1993年   1555篇
  1992年   2331篇
  1991年   2079篇
  1990年   1789篇
  1989年   1530篇
  1988年   1318篇
  1987年   1192篇
  1986年   955篇
  1985年   776篇
  1984年   509篇
  1983年   401篇
  1982年   250篇
  1981年   201篇
  1980年   230篇
  1979年   245篇
  1978年   149篇
  1977年   115篇
  1976年   105篇
  1974年   135篇
排序方式: 共有10000条查询结果,搜索用时 437 毫秒
991.
We present two case studies, one of generalized chorea and one of hemichorea, both after severe hypoglycemia episodes. Both cases showed hyperperfusion in their SPECT scans. The MRI and SPECT findings serve as clues regarding the role of basal ganglion dysfunction associated with chorea.  相似文献   
992.
993.
994.
995.
移植肾破裂的处理   总被引:4,自引:0,他引:4  
目的 提高移植肾破裂的防治水平。方法  6例移植肾破裂 ,手术前 2例 ,手术后 4例。 2例术前供肾破裂 ,采用切开移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾。 1例术后移植肾破裂早期 ,出血少 ,针对顽固性高血压采用“硝普钠”降压 ,配合常规抗排斥药物。 3例术后移植肾破裂出血量估计超过 10 0 0ml者 ,采用手术延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾。结果  ( 1)手术前 2例手术后 4例 ,采用切开或者延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾并配合“硝普钠”降压的方法处理 ,均未再破裂出血 ,移植肾功能恢复良好。 ( 2 ) 1例术后移植肾破裂早期的患者 ,针对顽固性高血压采用“硝普钠”降压 ,配合常规抗排斥药物 ,非手术治疗成功。结论  ( 1)采用手术切开或延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾可以有效治疗移植肾破裂。 ( 2 )移植肾破裂出血少的情况下 ,可以在密切观察下非手术治疗  相似文献   
996.
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus, it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule. Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus.  相似文献   
997.
Nuclear factor-kappaB (NF-kappaB) plays a key role in inflammation, which is involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). In the present study, we assessed the potential role of NF-kappaB in regulation of cerebral vasospasm. Nuclear factor-kappaB DNA-binding activity was measured in cultured vascular smooth muscle cells (VSMCs) treated with hemolysate and pyrrolidine dithiocarbamate (PDTC, 80 micromol/L), an inhibitor of NF-kappaB. Forty-two rabbits were divided into three groups: control, SAH, and PDTC groups (n=14 for each group). The caliber of the basilar artery was evaluated. Nuclear factor-kappaB DNA-binding activity and the gene expression levels of cytokines and adhesion molecules in the basilar artery were measured. Immunohistochemical study was performed to assess the expression and localization of tumor necrosis factor (TNF)-alpha, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase (MPO). It was observed that NF-kappaB DNA-binding activity was significantly increased by treatment with hemolysate in cultured VSCMs, but this increase was suppressed by pretreatment with PDTC. Severe vasospasm was observed in the SAH group, which was attenuated in the PDTC group. Subarachnoid hemorrhage could induce increases of NF-kappaB DNA-binding activity and the gene expression levels of TNF-alpha, interleukin (IL)-1 beta, ICAM-1, and vascular cell adhesion molecule (VCAM)-1, which were reduced in the PDTC group. Immunohistochemical study demonstrated that the expression levels of TNF-alpha, ICAM-1, and MPO were all increased in the SAH group, but these increases were attenuated in the PDTC group. Our results suggest that NF-kappaB is activated in the arterial wall after SAH, which potentially leads to vasospasm development through induction of inflammatory response.  相似文献   
998.
From May 1, 1985 to December 31, 1991, a total of 4,962,707 serum samples from 8 population groups in Taiwan were tested for anti-human immunodeficiency virus type 1 (anti-HIV-1). In total, 256 samples were seropositive; of these individuals, 43 developed acquired immunodeficiency syndrome (AIDS): 29 were homosexuals; 5 were hemophiliacs; 8 were heterosexuals and 1 was of unknown risk. Although the prevalence of HIV-1 infection and AIDS remains low compared with other countries, since 1988 the increase has been rapid. Before 1977 the majority were homosexuals and hemophiliacs; thereafter the risk groups diversified, with a trend away from homosexuals and hemophiliacs towards heterosexuals and intravenous drug abusers (IVDAs). A few patients have caused serious social problems for the public, health care workers and families. Active community efforts are needed to achieve future success in the control of HIV-1 infection and AIDS in Taiwan.  相似文献   
999.
α adrenoreceptor 301–303 deletion polymorphism does not influence basal metabolic rate, insulin resistance or weight gain in Greek women with polycystic ovary syndrome.  相似文献   
1000.
目的:探讨老年缺血性脑血管疾病患者脑血流灌注与颈动脉超声各项指标之间的联系,寻求脑血管硬化的预测因子.材料和方法: 对44例经SPECT证实为缺血性脑血管疾病的老年患者作颈动脉超声检查,作超声各项指标与平均脑血流的相关分析.结果: 缺血性脑血管疾病患者的平均脑血流与患侧颈总动脉、颈内动脉的收缩期峰流速、舒张末流速以及颈动脉CAS斑块积分成正相关,而与颈总动脉的阻力指数呈负相关.结论: 颈动脉血流速度以及颈动脉斑块CAS积分可有效的估计老年缺血性脑血管疾病患者的脑血流灌注情况以及缺血的严重程度.  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