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   2661348篇
  免费   191258篇
  国内免费   5174篇
耳鼻咽喉   36606篇
儿科学   88334篇
妇产科学   74754篇
基础医学   380592篇
口腔科学   76920篇
临床医学   234544篇
内科学   517280篇
皮肤病学   58953篇
神经病学   206847篇
特种医学   101777篇
外国民族医学   597篇
外科学   406871篇
综合类   59833篇
现状与发展   5篇
一般理论   776篇
预防医学   197707篇
眼科学   63066篇
药学   197810篇
  8篇
中国医学   6124篇
肿瘤学   148376篇
  2018年   28275篇
  2017年   21397篇
  2016年   23802篇
  2015年   27162篇
  2014年   37724篇
  2013年   55939篇
  2012年   77240篇
  2011年   82022篇
  2010年   48528篇
  2009年   45546篇
  2008年   77257篇
  2007年   82805篇
  2006年   83685篇
  2005年   80874篇
  2004年   78075篇
  2003年   74779篇
  2002年   72704篇
  2001年   129808篇
  2000年   133184篇
  1999年   111302篇
  1998年   30421篇
  1997年   26816篇
  1996年   26969篇
  1995年   25711篇
  1994年   23987篇
  1993年   22080篇
  1992年   86842篇
  1991年   84447篇
  1990年   81997篇
  1989年   79296篇
  1988年   72969篇
  1987年   71439篇
  1986年   67754篇
  1985年   64532篇
  1984年   47664篇
  1983年   41004篇
  1982年   23664篇
  1981年   21118篇
  1979年   43681篇
  1978年   30317篇
  1977年   26056篇
  1976年   24344篇
  1975年   26268篇
  1974年   31540篇
  1973年   30330篇
  1972年   28556篇
  1971年   26414篇
  1970年   24648篇
  1969年   23426篇
  1968年   21990篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation.  相似文献   
993.
A goal for the obstetrician and neonatologist is to screen for risk factors associated with intraventricular hemorrhage (IVH) in the low-birthweight infant. Perinatal events that lead to neonatal metabolic and cardiovascular derangements seem to provoke IVH, and conflicting reports have implicated labor as being contributory. A fetal heart rate (FHR) abnormality during premature labor may be a predictor of subsequent neonatal IVH. For this reason, 5 years of FHR tracings at two university medical centers were reviewed for inborn infants who were delivered after premature labor and weighed less than or equal to 2000 gm. Sixty-four infants developed IVH, but pre-existing labor with a discernible FHR pattern was recorded in only 38 (59%) cases. Interpretations were reassuring in 17 (45%) cases, suspicious in 7 (18%) cases, and ominous in 14 (37%) cases. This proportion of FHR patterns was not significantly different from a matched group of premature infants without IVH during the same period. Interpretations of intrapartum FHR patterns of low-birthweight infants are limited, especially before 30 weeks gestation, and not useful in predicting neonatal IVH.  相似文献   
994.
Several types of neurons were differentiated on the basis of a study of neuronal activity in various parts of the cortex near the sulcus principalis during the execution of spatial delayed reactions by monkeys. It was established that the different types of neurons are represented in different numbers in. different parts of the cortex near the sulcus principalis. The determination of several factors influencing the activity of these neurons and the comparison of data on their quantitative representation in the anterior, middle, and posterior parts of the cortex near the sulcus principalis with the existing behavioral data obtained after local ablations of identical regions of the brain made it possible to postulate that neurons belonging to the different types are involved in the analysis of different processes and represent different functional units.Translated from Fiziologicheskii. Zhurnal SSSR imeni I. M. Sechenova, Vol. 71, No. 12, pp. 1488–1494, December, 1985.  相似文献   
995.
996.
This paper outlines the impact of granulocyte‐colony stimulating factor (G‐CSF) used as a single modality therapy in 17 patients with secondary autoimmune neutropenia (S‐AIN) who had been treated a multiple number of times previously. Fifteen of these patients had demonstrable antineutrophil antibodies and two had cellular S‐AIN with haemopoietic inhibitory T‐cells present in the marrow. Prior to treatment, all had had problems with infection. All patients responded within 7 days of commencement of treatment. Provided G‐CSF neutrophil counts were maintained above 1 × 109/l, no further infections occurred. This was achievable by using G‐CSF administered as infrequently as once every 8 days. Eight of the 17 patients remained on G‐CSF, although five switched to the glycosylated form because of side‐effects. None have developed osteoporosis despite 47.29 patient years of total experience with G‐CSF. In conclusion both glycosylated and nonglycosylated G‐CSF can be used effectively in treating AIN on a long‐term basis.  相似文献   
997.
998.
结果 髌股关节的压力与应力随膝关节屈曲角度的增加而升高,随膝关节屈曲角度的减小而降低(图3~8).不同膝关节屈曲角度下弓步变化和跨步变化的髌股关节压力见表1.  相似文献   
999.
1000.
Infantile Digital Fibroma Treated With Mohs Micrographic Surgery   总被引:2,自引:0,他引:2  
John G. Albertini  MD  Maj  USAF  MC  Michael Jude Welsch  MD  CPT  USA  MC  Leo A. Conger  MD  LTC  USA  MC  Lester F. Libow  MD  COL  USA  MC    Dirk M. Elston  MD  COL  USA  MC 《Dermatologic surgery》2002,28(10):959-961
BACKGROUND: Infantile digital fibroma (IDF) is a rare benign fibrous tumor of childhood that frequently recurs despite local excision. Conservative, nonsurgical management may result in regression and/or joint deformity. OBJECTIVE: To describe the histologic features of IDF and discuss a case excised using Mohs micrographic surgery (MMS). METHODS: Case report and review of the clinical, histologic, and ultrastructural features. RESULTS: Characteristic inclusion bodies of actin were identified with hematoxylin and eosin, Masson's trichrome, and rapid actin immunostain. The tumor was debulked and the majority was removed after one stage of MMS, except where the deep margin approached the joint space. The defect healed by secondary intention. At 2 years the patient had no recurrence or functional joint deformity. CONCLUSION: MMS is a surgical treatment option for IDF.  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