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   429308篇
  免费   31223篇
  国内免费   10578篇
耳鼻咽喉   4476篇
儿科学   10980篇
妇产科学   7621篇
基础医学   33426篇
口腔科学   9501篇
临床医学   45652篇
内科学   52466篇
皮肤病学   5480篇
神经病学   22015篇
特种医学   9646篇
外国民族医学   37篇
外科学   42786篇
综合类   68990篇
现状与发展   25篇
一般理论   53篇
预防医学   42327篇
眼科学   5946篇
药学   40630篇
  661篇
中国医学   52720篇
肿瘤学   15671篇
  2024年   1314篇
  2023年   7117篇
  2022年   12188篇
  2021年   17536篇
  2020年   16420篇
  2019年   21865篇
  2018年   19129篇
  2017年   16452篇
  2016年   13698篇
  2015年   12785篇
  2014年   26896篇
  2013年   27518篇
  2012年   24521篇
  2011年   26420篇
  2010年   21151篇
  2009年   18810篇
  2008年   17823篇
  2007年   18374篇
  2006年   15806篇
  2005年   13569篇
  2004年   11016篇
  2003年   9606篇
  2002年   7531篇
  2001年   6765篇
  2000年   5610篇
  1999年   4751篇
  1998年   3850篇
  1997年   3693篇
  1996年   3172篇
  1995年   3003篇
  1994年   2861篇
  1993年   2259篇
  1992年   2305篇
  1991年   1998篇
  1990年   1730篇
  1989年   1537篇
  1988年   1438篇
  1985年   4691篇
  1984年   6043篇
  1983年   4498篇
  1982年   4643篇
  1981年   4447篇
  1980年   3902篇
  1979年   3574篇
  1978年   3116篇
  1977年   2247篇
  1976年   2695篇
  1975年   2101篇
  1974年   1835篇
  1973年   1672篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
小儿乙状结肠冗长症病理特点分析   总被引:11,自引:0,他引:11  
目的 探讨小儿乙状结肠冗长症的病理特点,以提高对该症病理特点的认识。方法 分析我科1993~2002年间经手术治疗12例小儿乙状结肠冗长症的临床病理资料。结果 小儿乙状结肠冗长症病理特点与先天性巨结肠同源病相似。主要表现为乙状结肠肠壁肥厚,部分肌纤维变性。结肠黏膜萎缩,黏膜下充血水肿;肌间神经丛减少,均可见神经节细胞发育幼稚,且数量减少或体积变小,呈固缩或空泡变性。结论 小儿乙状结肠冗长症大多有肠神经元发育异常。  相似文献   
992.
介绍了一种从谷朊粉废水中提取戊聚糖的工艺,由此工艺得到的产品(戊聚糖质量分数约70%,蛋白质质量分数约20%)能较好地保持戊聚糖的特性.研究了其它添加剂(卡拉胶)对戊聚糖的乳化性,戊聚糖对肉制品持油、持水性以及其质构的影响.谷朊粉废弃水提取物与卡拉胶的复配产品在添加量(质量分数)为6%时能使肉制品有较好的持油性和相应的质构.  相似文献   
993.
本文作者比较了不同时期的纸质病案的使用率,讨论了旧病案的缺点,如难于保存,占用空间及实用价值不大.作者提出了改进保存病案的办法.  相似文献   
994.
目的 探讨提高上尿路结石碎石成功率的微创治疗方法。方法 采用经皮肾穿微造瘘输尿管镜气压弹道碎石,术中放置双J管,术后配合体外冲击波碎石术(ESWL)治疗上尿路结石48例。结果 结石总排净率为89.1%,结石最小排净率79.2%,无严重并发症发生。结论 该方法结石排净率高,创伤较小,手术并发症少,是上尿路结石较为理想的微创治疗方法。  相似文献   
995.
中西药合用对帕金森病大鼠旋转行为的影响   总被引:4,自引:1,他引:3  
目的 观察中西药合用对帕金森病(Parkinson disease,PD)大鼠旋转行为的影响。方法 采用6羟多巴胺注射于脑右侧黑质造成偏侧帕金森病模型,并用滋补肝肾、通络解毒的中药以及西药美多巴进行治疗,同时设立美多巴对照组,观察中西药合用对PD大鼠旋转行为的影响。结果 中西药合用可使模型大鼠的旋转圈数明显减少。结论 中西药合用能明显改善PD模型大鼠的旋转行为。  相似文献   
996.
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting.  相似文献   
997.
M. Spilsbury 《Haemophilia》2004,10(S4):25-29
Summary.  This paper is based on the assumption that psychosocial services can add important mental and social dimensions to the traditional concepts of help and medicine. Peer support which has been established world-wide for people with haemophilia and their families is invaluable and irreplaceable. However the role of the professional psychosocial worker is underutilized in most countries, mostly because of lack of financial resources. This paper will argue that skilled workers can assist individuals and groups to reach their full potential in a variety of creative and non-threatening ways. Psychosocial workers have strict codes of conduct and requirements relating to accreditation to ensure accountability in their work. They can work in a variety of individual roles and have a wide range of individual mandates within work settings.  相似文献   
998.
The naevus of Ota (naevus fusculocoeruleus ophthalmomaxillaris) was first described by the Japanese dermatologist M. T. Ota in 1939. It has a reported incidence of 0.2% to 1% in the Japanese population. It usually occurs in the skin innervated by the first or second branch of the trigeminal nerve. The naevus comprises dermal melanocytes and is congenital or acquired during adolescence. Commonly associated lesions include scleral melanocytosis and other ocular manifestations as well as lesions of the tympanic membrane, oral and intranasal mucosa and leptomeninges. Diseases associated with Ota's naevus in rare cases are open-angle glaucomas and melanoma. The naevus of Ota in Europeans is a rare manifestation. We report the very rare case of a bilateral naevus of Ota associated with enoral melanocytosis in a white European person.  相似文献   
999.
Using an information-theoretic approach, causality between the systolic amplitude in blood pressure and the frequency of the heart beat was analyzed. Blood pressure and ECG were noninvasively recorded in young, healthy subjects. Three successive measurements were performed: during spontaneous breathing and during paced respiration—at frequencies both higher and lower than that of spontaneous respiration. We demonstrate that the amplitude and frequency of the cardiac rhythm are synchronized for most of the time. The synchronization is stronger during paced respiration at a frequency lower than that of spontaneous breathing. Episodes where the cardiac frequency was driven by the systolic pressure were also detected during slow, paced respiration.  相似文献   
1000.
新生儿产伤79例分析   总被引:3,自引:1,他引:2  
目的了解新生儿产伤种类及相关因素.方法用回顾性分析方法对该院23年间分娩造成的新生儿产伤共79例进行分析.结果23年间共分娩25 916例次,分娩造成的新生儿产伤共79例,发生率为3.05‰.产伤类型包括:骨折、臂丛神经损伤、产钳伤、刀伤、面瘫、口底损伤,其中以骨折为最多,计33例,占41.77%,骨折中颅骨骨折所占比例最大,25例(75.76%).与产伤关系最为密切的分娩方式是产钳助产.体重≥2500 g,发生新生儿产伤71例,占89.87%.新生儿产伤Apgar评分≤7分56例,占70.89%.结论正确选择分娩方式,把新生儿产伤降到最低点.  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