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   2107篇
  免费   145篇
  国内免费   8篇
耳鼻咽喉   13篇
儿科学   163篇
妇产科学   47篇
基础医学   311篇
口腔科学   15篇
临床医学   275篇
内科学   296篇
皮肤病学   31篇
神经病学   231篇
特种医学   51篇
外科学   196篇
综合类   68篇
一般理论   2篇
预防医学   250篇
眼科学   18篇
药学   159篇
中国医学   3篇
肿瘤学   131篇
  2023年   21篇
  2022年   25篇
  2021年   63篇
  2020年   40篇
  2019年   42篇
  2018年   51篇
  2017年   31篇
  2016年   58篇
  2015年   47篇
  2014年   68篇
  2013年   111篇
  2012年   151篇
  2011年   141篇
  2010年   69篇
  2009年   68篇
  2008年   130篇
  2007年   132篇
  2006年   134篇
  2005年   137篇
  2004年   105篇
  2003年   126篇
  2002年   104篇
  2001年   22篇
  2000年   20篇
  1999年   17篇
  1998年   27篇
  1997年   20篇
  1996年   14篇
  1995年   10篇
  1994年   14篇
  1993年   15篇
  1992年   20篇
  1990年   10篇
  1989年   6篇
  1988年   12篇
  1986年   12篇
  1985年   9篇
  1984年   9篇
  1983年   9篇
  1982年   11篇
  1981年   12篇
  1980年   10篇
  1979年   11篇
  1978年   7篇
  1977年   12篇
  1976年   6篇
  1974年   8篇
  1973年   8篇
  1972年   7篇
  1968年   5篇
排序方式: 共有2260条查询结果,搜索用时 15 毫秒
1.
The purpose of this study is to determine the role of liver biopsy and outcome of patients undergoing donor evaluation for adult-to-adult right hepatic lobe living donor liver transplantation (LDLT). Records of patients presenting for a comprehensive donor evaluation between 1997 and February 2005 were reviewed. Liver biopsy was performed only in patients with risk factors for abnormal histology. Two hundred and sixty patients underwent a comprehensive donor evaluation and 116 of 260 (45%) were suitable for donation, 14 of 260 (5.4%) did not complete evaluation and 130 of 260 (50%) were rejected. Four patients underwent unsuccessful hepatectomy surgery due to discovery of intraoperative abnormalities. Between 1997 and 2001, the acceptance rate of donor candidates (63%) was higher than 2002-2005 (36%), p < 0.0001. Sixty-six of the 150 eligible patients (44%) fulfilled criteria for liver biopsy and 28 of 66 (42%) had an abnormal finding. Less than half of the patients undergoing donor evaluation were suitable donors and the donor acceptance rate has declined over time. A large proportion of the patients undergoing liver biopsy have abnormal findings. Our evaluation process failed to identify 4 of 103 who had aborted donor surgeries.  相似文献   
2.
SUPER IF ON     
Meyer  Harriet S. 《JAMA》2006,295(7):833
  相似文献   
3.
Summary Candida endocarditis is an unusual but severe complication of systemic infection caused byCandida albicans and occasionally by other fungal species. We describe seven cases that occurred during a period of 20 years in western Sweden. In four cases infections were located on prosthetic valves and in three cases native valves were involved. Three patients died of the disease in the acute phase. A definite diagnosis was established in one of four survivors. This patient had an aortic valve endocarditis and a saddle embolisation and was treated with immediate surgery, followed by intensive treatment with liposomal amphotericin B + flucytosine. Fungal endocarditis is still a serious disease with a high mortality and whenever the diagnosis is suspected, antifungal therapy must be started and transesophageal sonography should be performed to visualize vegetations. Immediate surgery should be considered.
Pilzendokarditis — Bericht über sieben Fälle und kurze Literaturübersicht
Zusammenfassung DieCandida-Endokarditis ist eine seltene, aber schwere Komplikation einer systemischen Infektion durchCandida albicans und gelegentlich auch durch andere Pilzspezies. Wir berichten über sieben Fälle, die in einem Zeitraum von 20 Jahren in Westschweden beobachtet wurden. In vier Fällen waren Klappenprothesen und in drei Fällen natürliche Klappen betroffen. Drei Patienten starben in der akuten Phase an der Krankheit. Bei einem der vier überlebenden Patienten konnte die Diagnose eindeutig gesichert werden. Dieser Patient hatte eine Aortenklappenendokarditis und einen reitenden Embolus. Er wurde sofort operiert und hochdosiert mit liposomalem Amphotericin B und mit Flucytosin behandelt. Die Pilzendokarditis ist nach wie vor eine ernste, mit hoher Letalität belastete Krankheit. Die antimykotische Therapie muß bereits beim ersten Verdacht begonnen werden. Um Vegetationen nachzuweisen, sollte die transösophageale Sonographie durchgeführt werden. Ein sofortiges chirurgisches Eingreifen ist zu erwägen.
  相似文献   
4.
5.
This article describes family well being after a child's intensive care nursery experience. Thirty families of children who were graduates of intensive care nurseries participated in the study. Fifteen families of children with identifiable disabilities and 15 families of children with no identifiable disabilities were interviewed and completed standardized questionnaires. A comparison of family well being was done across three dimensions: the child's characteristics and caregiving needs, the family's support resources and needs, and the family's values and beliefs regarding their child's hospitalization and resulting special needs. Both groups of families had realized a renewed sense of meaning concerning family, children, and life itself due to their child's medical crises or disability. Families of children with disabilities, however, noted their financial concerns, burdens with their child's caregiving, and their difficulty in locating services for their child. These families' experiences underscore the need for a coordinated transition from the hospital to the community for the family and child.  相似文献   
6.
When, in the early 1960s, Thomas K. Hunt, MD began investigating the role of oxygen in wound healing, he recognized that translation to humans would require the ability to measure oxygen tension in human wounds. This article will review his contributions to the development of subcutaneous tissue oxygen measurement and to the understanding of wound physiology and oxygen delivery, particularly through use of oxygen measurement. Hunt's major contributions to the field include the observations that all wounds show some degree of hypoxia, while many are severely hypoxic; the degree of hypoxia in wounds is sufficient to impair wound healing, and particularly bacterial killing by neutrophils, collagen deposition, angiogenesis, and epithelization; the sympathetic nervous system plays a central role in decreasing wound oxygen supply; and wound oxygen delivery and wound healing capacity can be increased by controlling the sympathetic nervous system. All these observations required tissue oxygen measurement, and, in particular, translation of basic scientific observations to clinical research required a method of measuring wound oxygen tension in humans.  相似文献   
7.
8.
Background: Erythrocytes are transfused to improve oxygen delivery and prevent or treat inadequate oxygenation of tissues. Acute isovolemic anemia subtly slows human data processing and degrades memory, increases heart rate, and decreases self-assessed energy level. Erythrocyte transfusion is efficacious in reversing these effects of acute anemia. We tested the hypothesis that increasing arterial oxygen pressure (Pao2) to 350 mmHg or greater would supply sufficient oxygen to be equivalent to augmenting hemoglobin concentration by 2-3 g/dl and thus reverse the effects of acute anemia.

Methods: Thirty-one healthy volunteers, aged 28 +/- 4 yr (mean +/- SD), were tested with verbal memory and standard, computerized neuropsychologic tests before and twice after acute isovolemic reduction of their hemoglobin concentration to 5.7 +/- 0.3 g/dl. Two sets of tests were performed in randomized order at the lower hemoglobin concentration: with the volunteer breathing room air or oxygen. The subject and those administering the tests and recording the results were unaware which gas was administered. As an additional control for duration of the experiment, 10 of these volunteers also completed the same tests on a separate day, without alteration of hemoglobin concentration, at times of the day similar to those on the experimental day. Heart rate, mean arterial blood pressure, and self-assessed sense of energy were recorded at the time of each test.

Results: Reaction time for digit-symbol substitution test increased, delayed memory was degraded, mean arterial pressure and energy level decreased, and heart rate increased at a hemoglobin concentration of 5.7 g/dl (all P < 0.05). Increasing Pao2 to 406 +/- 47 mmHg reversed the digit-symbol substitution test result and the delayed memory changes to values not different from those at the baseline hemoglobin concentration of 12.7 +/- 1.0 g/dl, and decreased heart rate (P < 0.05). However, mean arterial pressure and energy level changes were not altered with increased Pao2 during acute anemia.  相似文献   

9.
10.

Background  

Many studies have found socioeconomic differentials in cancer survival. Previous studies have generally demonstrated poorer cancer survival with decreasing socioeconomic status but mostly used only ecological measures of status and analytical methods estimating simple survival. This study investigate socio-economic differentials in cancer survival using four indicators of socioeconomic status; three individual and one ecological. It uses a relative survival method which gives a measure of excess mortality due to cancer.  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