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   566篇
  免费   106篇
  国内免费   5篇
耳鼻咽喉   2篇
儿科学   11篇
妇产科学   4篇
基础医学   25篇
口腔科学   9篇
临床医学   76篇
内科学   189篇
神经病学   39篇
特种医学   193篇
外科学   67篇
综合类   10篇
预防医学   14篇
眼科学   2篇
药学   17篇
肿瘤学   19篇
  2023年   11篇
  2021年   6篇
  2020年   6篇
  2019年   4篇
  2018年   26篇
  2017年   15篇
  2016年   18篇
  2015年   20篇
  2014年   42篇
  2013年   46篇
  2012年   12篇
  2011年   18篇
  2010年   33篇
  2009年   43篇
  2008年   25篇
  2007年   20篇
  2006年   9篇
  2005年   14篇
  2004年   21篇
  2003年   10篇
  2002年   10篇
  2001年   8篇
  2000年   9篇
  1999年   9篇
  1998年   21篇
  1997年   23篇
  1996年   16篇
  1995年   13篇
  1994年   9篇
  1993年   16篇
  1992年   4篇
  1991年   3篇
  1990年   7篇
  1989年   21篇
  1988年   16篇
  1987年   13篇
  1986年   8篇
  1985年   13篇
  1984年   4篇
  1983年   4篇
  1982年   9篇
  1981年   6篇
  1980年   9篇
  1979年   4篇
  1978年   3篇
  1977年   6篇
  1976年   7篇
  1975年   4篇
  1971年   1篇
  1961年   1篇
排序方式: 共有677条查询结果,搜索用时 0 毫秒
71.

Purpose

During the mechanical ventilation weaning process, the spontaneous breathing trial (SBT) is the confirmatory test of patients' capability to breathe unassisted. However, the SBT interobserver agreement rate (its reliability) is unknown, and our objective was to evaluate it.

Materials and Methods

This is a prospective, multicentric and observational study. Patients were included when the SBT criteria were fulfilled. Two physicians and 2 respiratory therapists (RTs) rated each SBT. The SBT interobserver agreement was measured using κ statistic and also the percentage of agreement with its 95% credible interval (CrI) calculated by a Bayesian inference.

Results

Ninety-three distinct physicians and 91 distinct RTs rated 130 SBTs. The κ coefficient was 0.46 for physicians and 0.57 for RT, indicating a moderate interobserver agreement rate. The percentage of agreement was 87.7% between physicians (95% CrI, 81.0%-92.3%) and 86.2% between RT (95% CrI, 79.2%-91.1%). The physicians' and RT' percentage of agreement were not statistically different (P = .71).

Conclusions

The SBT interobserver agreement rate is only moderate for physicians and RT. The percentage of agreement between 2 different SBT observers is 79.2% to 92.3%. Therefore, a relevant percentage of patients will have different extubation decisions depending on the SBT observer.  相似文献   
72.
73.
Objectives: Boarding admitted patients in emergency department (ED) treatment beds has been recognized as a major cause of ED crowding and ambulance diversions. When process delays impede the transfer of admitted patients from the ED to inpatient units, the department's capacity to accept new arrivals and to generate revenue from additional patient services is restricted. The objective of this study was to determine the amount of functional ED treatment capacity that was used to board inpatients during 12 months of operations at a community hospital and to estimate the value of that lost treatment capacity.
Methods: Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in south central Pennsylvania between July 2004 and June 2005 were used to determine the amount of treatment bed occupancy lost to inpatient holding and the revenue potential of utilizing that blocked production capacity for additional patient visits.
Results: Transferring admitted patients from the ED to an inpatient unit within 120 minutes would have increased the functional treatment capacity of the ED by 10,397 hours during the 12 months of this study. By reducing admission process delays, the hospital could potentially have accommodated another 3,175 patient encounters in its existing treatment spaces. Providing emergency services to new patients in ED beds formerly used to board inpatients could have generated $3,960,264 in additional net revenue for the hospital.
Conclusions: Significantly higher operational revenues could be generated by reducing output delays that restrict optimal utilization of existing ED treatment capacity.  相似文献   
74.
75.
76.
The role of basal forebrain-derived cholinergic afferents in the development of neocortex was studied in postnatal rats. Newborn rat pups received intraventricular injections of 192 IgG-saporin. Following survival periods ranging from 2 days to 6 months, the brains were processed to document the cholinergic lesion and to examine morphological consequences. Immunocytochemistry for choline acetyltransferase (ChAT) and in situ hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the cholinergic neurons in the medial septum and nucleus of the diagonal band of Broca in the basal forebrain. In situ hybridization for glutamic acid decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons. Acetylcholinesterase histochemistry demonstrates a marked reduction of the cholinergic axons in neocortex. Cholinergic axons are reduced throughout the cortical layers; this reduction is more marked in medial than in lateral cortical areas. The thickness of neocortex is reduced by approximately 10%. Retrograde labeling of layer V cortico-collicular pyramidal cells reveals a reduction in cell body size and also a reduction in numbers of branches of apical dendrites. Spine densities on apical dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated cases; no change was detected in number of spines on basal dendrites. These results indicate a developmental or maintenance role for cholinergic afferents to cerebral cortical neurons.   相似文献   
77.
78.
79.
80.
Mahoney  MC; Shipley  RT 《Radiology》1988,166(3):721-723
Following lobectomy of the right upper lobe of the lung, a single fissure, the neofissure, separates the right middle and lower lobes. In 25 patients in whom chest radiographs and computed tomographic (CT) scans were obtained after right upper lobectomy, the neofissure was identifiable to some extent on the radiographs in seven (28%) and on CT scans in 24 (96%). Among those patients in whom the neofissure was seen in its entirety, in 12 of 20 (60%) it was oriented predominantly in the coronal plane, paralleling the course of the original major fissure but displaced anteriorly and superiorly. In seven of 20 patients (35%) the superior aspect was coronal, rotated clockwise toward the sagittal plane inferiorly. In one of 20 patients (5%) the neofissure was oriented predominantly in the sagittal plane. The right middle lobe lies anterior and medial to the neofissure; the right lower lobe lies posterior and lateral.  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