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   207388篇
  免费   18362篇
  国内免费   4379篇
耳鼻咽喉   3248篇
儿科学   4052篇
妇产科学   3569篇
基础医学   16521篇
口腔科学   7175篇
临床医学   19102篇
内科学   19717篇
皮肤病学   2384篇
神经病学   10254篇
特种医学   5653篇
外国民族医学   11篇
外科学   20157篇
综合类   33216篇
现状与发展   9篇
一般理论   24篇
预防医学   27619篇
眼科学   1981篇
药学   20029篇
  333篇
中国医学   26111篇
肿瘤学   8964篇
  2024年   788篇
  2023年   4010篇
  2022年   7351篇
  2021年   10256篇
  2020年   9918篇
  2019年   11287篇
  2018年   10001篇
  2017年   8586篇
  2016年   7641篇
  2015年   7121篇
  2014年   14095篇
  2013年   14310篇
  2012年   12631篇
  2011年   13500篇
  2010年   10855篇
  2009年   9375篇
  2008年   8661篇
  2007年   8755篇
  2006年   7443篇
  2005年   6301篇
  2004年   5229篇
  2003年   4655篇
  2002年   3572篇
  2001年   2973篇
  2000年   2640篇
  1999年   2154篇
  1998年   1718篇
  1997年   1548篇
  1996年   1248篇
  1995年   1194篇
  1994年   1088篇
  1993年   965篇
  1992年   876篇
  1991年   805篇
  1990年   701篇
  1989年   681篇
  1988年   632篇
  1987年   568篇
  1986年   522篇
  1985年   1776篇
  1984年   2051篇
  1983年   1285篇
  1982年   1705篇
  1981年   1180篇
  1980年   1010篇
  1979年   902篇
  1978年   736篇
  1977年   552篇
  1976年   693篇
  1975年   477篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
Zusammenfassung In einer tierexperimentellen Studie wurde die Durchblutung nach Anlage einer handgenähten und geklammerten End-zu-End-Anastomose am Schweinedickdarm verglichen. Bei keinem der 15 Tiere trat ein Nahtleck auf. Im Bereich handgeknoteter Fäden konnten einzelne umschriebene minderdurchblutete Gebiete festgestellt werden, die am 7. und 14. postoperativen Tag deutlich sichtbar wurden, wenn die Anastomosen vermehrt vascularisiert waren. Bei den Klammernähten wurden solche Ausfälle der Gewebsdurchblutung nicht gesehen. Die intramuralen Arterien zogen unbehindert durch die B-förmig gestalteten Klammern hindurch. Ein unauffälliges Gefäßmuster und eine abgeschlossene Anastomosenheilung wurden bei den Klammernähten nach 3 Wochen und bei Handnähten nach 4 Wochen beobachtet.
Blood supply of stapled and sutured colonic anastomoses
Summary The blood supply of end-to-end staple and suture lines in the pig colon was compared. In 15 operated animals there was no anastomotic leak. Sporadic circumscribed areas of restricted circulation could be noticed in hand-sewn anastomoses. This effect was marked on the 7th and 14th postoperative day, when vascularisation of the anastomoses was increased. Such lack of vascular supply was not seen in stapled anastomoses. The intramural arteries passed through the B-shaped staples without hindrance. An unremarkable vascular pattern and a completed healing of the anastomoses were observed after 3 weeks in staple lines and after 4 weeks in suture lines.
Herrn Prof. Dr. Dr. h.c. F. Stelzner zum 65. Geburtstag gewidmet  相似文献   
962.
目的 :探讨胫腓骨远端骨折治疗术式的选择、术中术后应注意的问题及其疗效。方法 :对不同类型的胫腓骨远端骨折 36例进行 8~ 18个月的随访 ,并结合临床及影像学资料 ,对其诊断、手术方法及治疗效果进行分析总结。结果 :本组术后 2 5~ 3 5个月骨折均愈合。踝关节功能优良率 77 7%。结论 :熟悉骨折的分型及相应内固定术式的选择 ;注重踝穴骨折的解剖复位及固定和踝关节的功能位固定及早期功能锻炼。  相似文献   
963.
964.
92例跟骨骨折后足部畸形功能障碍治疗探讨   总被引:6,自引:1,他引:5  
本文对92例106足波及距下关节的跟骨骨折治疗后1~6年遗留足畸形、功能障碍的病例(PALey:舌型17足,中央压陷型53足,严重粉碎型36足)进行了分析和总结。作者强调解剖复位、牢靠固定、一期植骨、早期关节持续被动运动及不过早负重是预防跟骨骨折众多并发症的重要措施。  相似文献   
965.
Risk factors for postoperative nausea and vomiting   总被引:9,自引:0,他引:9  
  相似文献   
966.
A study of C4 bound to human erythrocytes in vitro and in vivo has been made by immunoblotting with mouse monoclonal anti-C4c and anti-C4d and human polyclonal anti-C4d (Rodgers and Chido) following SDS-PAGE. Multi-banded patterns differentiated between C4A and C4B isotypes. Treatment of EC4b with trypsin eliminated immunoblotting but not agglutination reactions. Serum inactivation (factor I) of EC4b resulted in banding patterns similar to those obtained from patients' EC4d. Treatment of EC4b membranes with NH2OH affected many of the bands, two were lost, one was markedly reduced and others had altered SDS-PAGE mobility. Interpretation of the bands has been made in terms of C4-acceptor complexes and inactivation fragments of C4. A distinct difference in the banding of C4A and C4B isotypes has been detected.  相似文献   
967.
An enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of serum antibodies against group-specific epitopes of the glycoproteins (G1, G2) and nucleoprotein (NP) of the genus Hantavirus. This assay was used to study the kinetics of the development of serum antibodies after natural infection with Puumala-like virus in humans. To this end a panel of 34 serum samples collected from individuals at different times after natural infection was tested by the ELISA. The samples were also tested for specific IgM and IgG levels against Puumala-like virus, which provided confirmatory data about the presumed timing of infection. It was shown that serum antibodies against the G1 epitope were present in the acute and early convalescent period just before antibodies to the NP epitope could be demonstrated. In contrast, antibodies to two G2 epitopes were present not earlier than in the convalescent and late convalescent period. Since all these categories of antibodies seem to persist for long periods, antibodies against the G1 epitope and the NP epitope may be of specific diagnostic value. Furthermore, levels of G1-specific antibodies and antibodies to either NP or G2 may allow estimation of the time elapsed following initial infection.  相似文献   
968.
Background During the last decade, there has been a growing interest in outpatient support services for persons with intellectual disability (ID) and psychiatric and/or behavioural problems and their families. In this study, we explore the family burden that is associated with children or adults with ID and behavioural or psychiatric problems living at home. Method The research group consisted of 66 clients of In Casa, a project of outpatient treatment. Their average age is 18.97 years and their average IQ 55.37. The Reiss Screen for Maladaptive Behaviour (adults) or Reiss Scales for Children's Dual Diagnosis (children) and the Nijmegen Family Situation Questionnaire have been administered. Results About 62% of the children and 86% of the adults living at home and referred to In Casa have severe psychiatric or behavioural problems as measured by the Reiss scales. The dual diagnosis has a more negative impact on the family situation than the condition of ID only. Conclusion Parents consider the psychiatric or behavioural problems of their child to be an extra burden and feel it more difficult to raise and manage such a child. This impels them to change the situation and to call on the help of external services. Some methodological questions and the implications of the findings in terms of support needs are discussed.  相似文献   
969.
Background Germinal matrix and intraventricular hemorrhage (GMH/IVH) is a known complication occurring in the first week of life in preterm neonates. However, the precise time of its occurrence and the ideal time to perform diagnostic imaging studies remain controversial. The purpose of this paper is to address these two issues in our patient population to allocate our resources to those at highest risk.Materials and methods This study included 282 premature newborns (under 37 weeks of gestation) that were admitted to our neonate ICU in a year’s time and screened for GMH/IVH. They were grouped in four categories according to their weight at birth, and according to their gestational age. All patients had a daily cranial ultrasound during the first week. It was then repeated once in the second week and once in the third.Results We found that the incidence of GMH/IVH among preterm neonates was 44.68%. It was inversely related to the weight and the age of the newborn. The onset of bleeding coordinated with the occurrence of hypoxia and respiratory distress requiring mechanical ventilation. The majorities occurred in the first 7 days of life; they were mostly grade I and II according to the Papule classification and silent for the most part. Complications were present in 41% of the survivors.  相似文献   
970.
目的:探讨川芎嗪对大鼠缺血再灌注损伤基因表达谱的影响,筛选出肾损伤的相关基因.方法:将大鼠随机分为实验组与对照组.实验组以川芎嗪经大鼠尾静脉注射6周后,建立缺血性肾衰竭模型,运用基因总结技术检测川芎嗪对肾损伤相关基因表达的影响.结果:川芎嗪能使大鼠缺血再灌注损伤肾相关基因表达上调和下调,其中川芎嗪下调已命名的大鼠肾基因(Ratio<0.5)67个;川芎嗪上调已命名的大鼠肾基因(Ratio<0.5)26个.结论:川芎嗪通过下调或上调缺血再灌注损伤肾相关基因表达的活性对急性缺血再灌注损伤肾发生药理作用.  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