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   593篇
  免费   40篇
  国内免费   7篇
耳鼻咽喉   3篇
儿科学   31篇
妇产科学   2篇
基础医学   55篇
口腔科学   33篇
临床医学   51篇
内科学   130篇
皮肤病学   28篇
神经病学   10篇
特种医学   99篇
外科学   63篇
综合类   24篇
预防医学   31篇
眼科学   5篇
药学   58篇
中国医学   1篇
肿瘤学   16篇
  2022年   2篇
  2021年   15篇
  2020年   4篇
  2019年   3篇
  2018年   6篇
  2017年   6篇
  2016年   13篇
  2015年   13篇
  2014年   13篇
  2013年   28篇
  2012年   25篇
  2011年   12篇
  2010年   28篇
  2009年   29篇
  2008年   14篇
  2007年   12篇
  2006年   20篇
  2005年   18篇
  2004年   8篇
  2003年   15篇
  2002年   10篇
  2001年   11篇
  2000年   10篇
  1999年   22篇
  1998年   36篇
  1997年   26篇
  1996年   21篇
  1995年   13篇
  1994年   23篇
  1993年   23篇
  1992年   8篇
  1991年   7篇
  1990年   6篇
  1989年   13篇
  1988年   20篇
  1987年   13篇
  1986年   15篇
  1985年   8篇
  1984年   8篇
  1983年   6篇
  1982年   9篇
  1981年   12篇
  1980年   12篇
  1978年   4篇
  1977年   5篇
  1976年   9篇
  1975年   2篇
  1973年   1篇
  1957年   1篇
  1955年   1篇
排序方式: 共有640条查询结果,搜索用时 15 毫秒
71.
72.
Purpose.?The aim of the study was to evaluate which factors are associated with the use of healthcare a long time after severe burn injury.

Method.?After a review process based on clinical reasoning, 69 former burn patients out of a consecutive group treated at the Uppsala Burn Unit from 1980?–?1995 were visited in their homes and their use of care and support was assessed in a semi-structured interview. Post-burn health was assessed with the Burn-Specific Health Scale-Brief (BSHS-B) and personality was assessed with the Swedish universities Scales of Personality (SSP).

Results.?The participants were injured on average eight years previously. Thirty-four had current contact with healthcare due to their burn injury and had significantly lower scores on three BSHS-B-domains: Simple Abilities, Work and Hand function, and significantly higher scores for the SSP-domain Neuroticism and the SSP-scales Stress Susceptibility, Lack of Assertiveness, and lower scores for Social Desirability. There was no relation to age, gender, time since injury, length of stay, or to the surface area burned.

Conclusions.?A routine screening of personality traits as a supplement to long-term follow-ups may help in identifying the patient's need for care.  相似文献   
73.
74.
75.
The Mark IV system for radionuclide computed tomography of the brain   总被引:5,自引:0,他引:5  
  相似文献   
76.
An unusual family is described with a congenital bleeding disorder present in four males belonging to three generations. Of the three surviving affected males, all had splenomegaly and petechiae. The three had moderate thrombocytopenia (55-90 X 10(9)/liter) and markedly prolonged Ivy-template bleeding times (greater than 30 min). They were also noted to have reticulocytosis and, upon further investigation, imbalanced globin chain synthesis resembling that of beta-thalassemia minor. Studies on nine additional family members in four generations were normal except for slight elevations of reticulocyte counts in female members, one of whom had the abnormal globin chain synthesis ratio. In male members, the bleeding tendency and clinical signs always occurred in the presence of the globin chain synthesis defect and reticulocytosis. This previously undescribed condition was apparently transmitted as an X-linked disorder.  相似文献   
77.
78.
Saxton  HM; Borzyskowski  M; Mundy  AR; Vivian  GC 《Radiology》1988,168(1):147-150
Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant.  相似文献   
79.
Thrombin-induced secretion of serotonin from platelets can occur in seconds   总被引:1,自引:0,他引:1  
Gear  AR; Burke  D 《Blood》1982,60(5):1231-1234
The platelet release reaction was studied by a new quenched-flow approach. Platelets labeled with 14C-serotonin were reacted for short times (up to 5 sec) with thrombin and then quenched with glutaraldehyde or paraformaldehyde. Serotonin secretion began within 1 sec and was nearly complete by 4 sec. Aggregation recorded by a resistive-particle counter was similarly fast. Therefore, the quenched-flow system reveals that serotonin secretion can occur more rapidly than estimated in earlier studies.  相似文献   
80.

Background and purpose:

ClC-K kidney Cl channels are important for renal and inner ear transepithelial Cl transport, and are potentially interesting pharmacological targets. They are modulated by niflumic acid (NFA), a non-steroidal anti-inflammatory drug, in a biphasic way: NFA activates ClC-Ka at low concentrations, but blocks the channel above ∼1 mM. We attempted to identify the amino acids involved in the activation of ClC-Ka by NFA.

Experimental approach:

We used site-directed mutagenesis and two-electrode voltage clamp analysis of wild-type and mutant channels expressed in Xenopus oocytes. Guided by the crystal structure of a bacterial CLC homolog, we screened 97 ClC-Ka mutations for alterations of NFA effects.

Key results:

Mutations of five residues significantly reduced the potentiating effect of NFA. Two of these (G167A and F213A) drastically altered general gating properties and are unlikely to be involved in NFA binding. The three remaining mutants (L155A, G345S and A349E) severely impaired or abolished NFA potentiation.

Conclusions and implications:

The three key residues identified (L155, G345, A349) are localized in two different protein regions that, based on the crystal structure of bacterial CLC homologs, are expected to be exposed to the extracellular side of the channel, relatively close to each other, and are thus good candidates for being part of the potentiating NFA binding site. Alternatively, the protein region identified mediates conformational changes following NFA binding. Our results are an important step towards the development of ClC-Ka activators for treating Bartter syndrome types III and IV with residual channel activity.  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