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   3489164篇
  免费   281797篇
  国内免费   14593篇
耳鼻咽喉   48464篇
儿科学   106934篇
妇产科学   91283篇
基础医学   546986篇
口腔科学   96880篇
临床医学   308374篇
内科学   618221篇
皮肤病学   93049篇
神经病学   297939篇
特种医学   138893篇
外国民族医学   453篇
外科学   543373篇
综合类   107087篇
现状与发展   24篇
一般理论   2262篇
预防医学   284316篇
眼科学   79627篇
药学   242986篇
  23篇
中国医学   10347篇
肿瘤学   168033篇
  2021年   54914篇
  2020年   35041篇
  2019年   58026篇
  2018年   70835篇
  2017年   54090篇
  2016年   59844篇
  2015年   73983篇
  2014年   108170篇
  2013年   173358篇
  2012年   90092篇
  2011年   89160篇
  2010年   115510篇
  2009年   120724篇
  2008年   77094篇
  2007年   80624篇
  2006年   91466篇
  2005年   86785篇
  2004年   89027篇
  2003年   80386篇
  2002年   70701篇
  2001年   109276篇
  2000年   102388篇
  1999年   101324篇
  1998年   65231篇
  1997年   63132篇
  1996年   60647篇
  1995年   56092篇
  1994年   50324篇
  1993年   47019篇
  1992年   71714篇
  1991年   68015篇
  1990年   64993篇
  1989年   64335篇
  1988年   60216篇
  1987年   58841篇
  1986年   56328篇
  1985年   55964篇
  1984年   50483篇
  1983年   45772篇
  1982年   42318篇
  1981年   39785篇
  1980年   37627篇
  1979年   42935篇
  1978年   37352篇
  1977年   34266篇
  1976年   31035篇
  1975年   30688篇
  1974年   32403篇
  1973年   31074篇
  1972年   29501篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Summary  We present the third case of Niemann–Pick disease type C without neurological symptoms. The patient was a 53-year-old woman without significant prior health problems who died of acute pulmonary embolism. Autopsy findings of hepatosplenomegaly, lymphadenopathy and ceroid-rich foam cells raised the suspicion of the visceral form of acid sphingomyelinase deficiency (Niemann–Pick disease type B; NPB) or a much rarer disorder, variant adult visceral form of Niemann–Pick disease type C (NPC). To verify the histopathological findings, SMPD1, NPC1 and NPC2 genes were analysed. Two novel sequence variants, c.1997G>A (S666N) and c.2882A>G (N961S) were detected in the NPC1 gene. No pathogenic sequence variants were found either in the SMPD1 gene mutated in NPB or in NPC2 gene. The pathogenicity of both NPC1 variants was supported by their location in regions important for the protein function. Both variations were not found in more than 300 control alleles. Identified sequence variations confirm the diagnosis of the extremely rare adult visceral form of Niemann–Pick disease type C, which is otherwise dominated by neurovisceral symptoms. Although only three patients have been reported, this (most probably underdiagnosed) form of NPC should be considered in differential diagnosis of isolated hepatosplenomegaly with foam cells in adulthood. Electronic supplementary material  Supplementary material is available for this article at  相似文献   
942.
A 65-year-old man developed acute limb ischemia, severe abdominal wall and lower limb livedo reticularis following a coronary angiogram. The differential diagnoses of acute limb ischemia and multiple cholesterol emboli syndrome (MCES) are discussed. This work was performed at Long Island Jewish Medical Center, 270-05, 76th Avenue, New Hyde Park, NY 11040.  相似文献   
943.
We describe the simple adaptation of a standard fluorescent microscope for illumination using a 'Royal Blue' Luxeon light emitting diode (LED) and demonstrate that this form of illumination is suitable for the detection of auramine O stained Mycobacterium spp. The low cost, low power consumption, safety and reliability of LEDs makes them attractive alternatives to mercury vapour lamps.  相似文献   
944.
945.
946.
精神分裂症首次发病患者的磁共振弥散张量显像研究   总被引:1,自引:0,他引:1  
目的探讨从未用过药的精神分裂症首次发病(以下简称首发)患者的重要白质及部分灰质区的磁共振弥散张量显像(DTI)的特点。方法选取9例首发精神分裂症患者(患者组)及9名年龄、性别、受教育程度与患者组相配对的健康者,应用DTI成像技术检测脑额颞交界处、内囊等白质区和颞中回灰质、中央前回、中央后回等灰质区的各向异性(FA)、表观扩散系数(ADC)及双侧海马体积。结果患者组及对照组组内左右两侧兴趣区FA值及ADC值的差异无统计学意义(P>0.05);患者组与对照组各感兴趣区FA值差异无统计学意义(P>0.05),但患者组颞中回灰质(8.655×10-9)、中央前回(7.816×10-9)、中央后回(7.855×10-9)ADC值高于对照组(分别为7.428×10-9,6.921×10-9,7.013×10-9;P=0.049,0.009,0.005);两组内及组间双侧海马体积比较,差异均无统计学意义(P>0.05)。结论首发精神分裂症患者与健康者DTI参数之间没有明显区别。  相似文献   
947.
948.
目的 探讨术中电生理监护对椎管神经鞘瘤显微手术中的作用及意义,提高对椎管内神经鞘瘤的治疗水平。方法 回顾性分析65例术中电生理动态监护下,显微手术切除椎管内神经鞘瘤。结果 治愈60例(占92.3%),好转5例(占7.7%),无死亡;肿瘤全切62例,次全切除3例,全切率95.4%。结论 常规动态电生理监测下显微手术切除椎管神经鞘瘤,能保全脊髓神经的功能,减少副损伤,提高手术安全性;显微手术有助于提高肿瘤全切率,可有效减少术后复发。对影响脊柱稳定性的行脊柱融合内固定。  相似文献   
949.
Aggressive behavior linked to corticotropin-reactive autoantibodies.   总被引:3,自引:0,他引:3  
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones.  相似文献   
950.
Zusammenfassung Diese Studie untersucht, wie Erfolg im Einzelcoaching entsteht und was Psychodrama dazu beitragen kann. Dabei werden zun?chst die vier Berner Wirkfaktoren dargestellt, die im Rahmen einer allgemeinen psychologischen Coachingkonzeption die vier m?glichen Erfolgsstrategien darstellen. über Videoauswertung und schriftliche Befragung aller Beteiligten wurden 35 Einzelsitzungen evaluiert. Dabei zeigten sich die vier Wirkfaktoren tats?chlich als elementar in kurz- und mittelfristig erfolgreichen Coachingprozessen. In dem experimentellen Vergleich wurde das psychodramatische Coaching zudem wesentlich besser bewertet als das Vergleichscoaching, was durch den Ressourcen- und Wachstumsfokus sowie die sehr gute Beziehungskompetenz der Psychodramatiker erkl?rt werden kann. Des Weiteren zeigen die Auswertungen, dass ein dosierter und gezielter Einsatz des psychodramatischen Methodenrepertoires fruchtbarer zu sein scheint als der zeitlich umfassende Einsatz des Psychodramas als Hauptinterventionsmethode.
Summary The present study investigates the process of success development in one-to-one-coaching and examines how the method of psychodrama can contribute to this process. First the four change factors are presented. They represent the four success strategies in a general psychological coaching approach that can be chosen by the coach. Second 35 one-to-one-coaching sessions are evaluated by a video-based rating-system and questionnaires that were filled in by all coaches, clients and employees of the clients. In these analyses the four change factors were shown to be critical for short- and medium-term success. In an experimentally designed assessment the psychodramatic coachings had a considerably better result than the comparative coaching. This outcome could be explained by the focus on resources and growth and the high competence of the psychodramatic coaches to set up an appreciative coaching relationship. The analyses demonstrate furthermore that the well-aimed and specific use of psychodrama methods is more fruitful than its time-extensive use as the main intervention method.


Peter Behrendt geb. 1977, Dipl. Psych., ausgebildeter Psychodrama-Therapeut und Mediator, seit 2004 freiberuflich Coaching, Moderation sowie Konzeption und Durchführung von Fortbildung und Trainings. Er konzipierte und leitete die Evaluationsstudie, die diesem Artikel zugrunde liegt.  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