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   382篇
  免费   31篇
  国内免费   2篇
儿科学   27篇
妇产科学   5篇
基础医学   56篇
口腔科学   3篇
临床医学   18篇
内科学   95篇
皮肤病学   7篇
神经病学   75篇
特种医学   2篇
外科学   23篇
综合类   2篇
预防医学   40篇
眼科学   13篇
药学   11篇
肿瘤学   38篇
  2023年   1篇
  2022年   1篇
  2021年   8篇
  2020年   4篇
  2019年   12篇
  2018年   10篇
  2017年   3篇
  2016年   5篇
  2015年   8篇
  2014年   13篇
  2013年   18篇
  2012年   24篇
  2011年   19篇
  2010年   11篇
  2009年   9篇
  2008年   16篇
  2007年   28篇
  2006年   32篇
  2005年   22篇
  2004年   32篇
  2003年   31篇
  2002年   24篇
  2001年   4篇
  2000年   5篇
  1999年   2篇
  1998年   8篇
  1997年   4篇
  1996年   6篇
  1995年   4篇
  1994年   4篇
  1993年   10篇
  1992年   3篇
  1991年   3篇
  1990年   5篇
  1989年   2篇
  1988年   3篇
  1987年   3篇
  1986年   3篇
  1985年   4篇
  1984年   2篇
  1983年   2篇
  1982年   1篇
  1981年   2篇
  1980年   1篇
  1978年   1篇
  1974年   1篇
  1973年   1篇
排序方式: 共有415条查询结果,搜索用时 15 毫秒
21.
The purpose of this article is to examine gender differences in social and psychological adjustment among cancer patients. The social adjustment and psychological distress of 49 patients (34 women and 15 men) undergoing active medical care (chemotherapy and radiation) were assessed. Socio-demographic and medical parameters were also examined to account for differences in adjustment. Three questionnaires were used: A personal information questionnaire; a Psychosocial Adjustment to Illness Scale (PAIS-SR) (Derogatis & Lopez, 1983); and a psychological distress one (BSI) (Derogatis & Spencer, 1982). Significant differences were found between men and women patients in several dimensions of the social adjustment, psychological distress and medical variables. Possible explanations, recommendations for further research and clinical intervention are suggested.  相似文献   
22.
OBJECTIVE: Previous studies have suggested that obesity enhances the inflammatory response, producing macromolecules involved in the induction and/or maintenance of increased erythrocyte aggregation. The objectives of this study were to evaluate the correlation between inflammation markers, erythrocyte adhesiveness/aggregation, and the degree of obesity and to assess phosphatidylserine expression on erythrocyte surface membrane of obese vs. nonobese individuals. RESEARCH METHODS AND PROCEDURES: Erythrocyte adhesiveness/aggregation in the peripheral venous blood was evaluated by using a new biomarker, phosphatidylserine expression was assessed by means of flow cytometry, and markers of inflammation were measured in 65 subjects: 30 obese [body mass index (BMI) = 41 +/- 7.7 kg/m(2)] and 35 nonobese (BMI = 24 +/- 2.7 kg/m(2)) individuals. Pearson correlations and Student's t test were performed. RESULTS: A highly significant difference was noted in the degree of erythrocyte adhesiveness/aggregation and markers of inflammation between the study groups. BMI correlated with erythrocyte adhesiveness/aggregation (r = 0.42, p = 0.001), erythrocyte sedimentation rate (r = 0.42, p = 0.001), high-sensitive C-reactive protein (r = 0.55, p < 10(-4)), fibrinogen (r = 0.37, p = 0.004), and white blood cell count (r = 0.45, p < 10(-4)). The degree of erythrocyte adhesiveness/aggregation correlated with erythrocyte sedimentation rate (r = 0.5, p < 10(-4)), high-sensitive C-reactive protein (r = 0.56, p < 10(-4)), fibrinogen (r = 0.54, p < 10(-4)), and white blood cell count (r = 0.32, p = 0.01). DISCUSSION: Our results suggest that obesity-related erythrocyte adhesiveness/aggregation is probably mediated through increased concentrations of adhesive macromolecules in the circulation and not necessarily through hyperlipidemia or phosphatidylserine exposure on erythrocyte's membrane.  相似文献   
23.
Slowness is a common complaint in children with attention-deficit hyperactivity disorder (ADHD) and with developmental right hemisphere syndrome. However, it was our clinical impression that slowness in developmental right hemisphere syndrome was more prominent than in ADHD. Our objective was to assess slowness as operationalized by speed of performance in children with developmental right hemisphere syndrome, children with ADHD, and controls. The research sample comprised 19 children in each group, matched for age, gender, socioeconomic status, IQ, and handedness. The subjects were administered a reaction time battery assessing speed of performance. Overall, the average performance differed among the three study groups (F(2,53) = 2.40, P < .01). Children with developmental right hemisphere syndrome were slower than their peers with ADHD (t(35) = 1.99, P < .05) and slower than controls (t(35) = 4.55, P < .001). Children with ADHD performed more slowly than controls, although for the majority of tasks, this was nonsignificant. We conclude that slowness is an integral and consistent component of developmental right hemisphere syndrome and cannot be attributed only to the ADHD symptomatology.  相似文献   
24.
Developmental dyscalculia   总被引:4,自引:0,他引:4  
Developmental dyscalculia is a specific learning disability affecting the acquisition of arithmetic skills in an otherwise-normal child. Although poor teaching, environmental deprivation, and low intelligence have been implicated in the etiology of developmental dyscalculia, current data indicate that this learning disability is a brain-based disorder with a familial-genetic predisposition. The neurologic substrate of developmental dyscalculia is thought to involve both hemispheres, particularly the left parietotemporal areas. Developmental dyscalculia is a common cognitive handicap; its prevalence in the school population is about 5–6%, a frequency similar to those of developmental dyslexia and attention-deficit-hyperactivity disorder. Unlike these, however, it is as common in females as in males. Developmental dyscalculia frequently is encountered in neurologic disorders, examples of which include attention-deficit-hyperactivity disorder, developmental language disorder, epilepsy, and fragile X syndrome. The long-term prognosis of developmental dyscalculia is unknown; it appears, however, to persist, at least for the short-term, in about half of affected preteen children. The consequences of developmental dyscalculia and its impact on education, employment, and psychologic well-being of affected individuals are unknown.  相似文献   
25.
After injury of their axons, damaged neurons shift their metabolic activity into a reparative mode aimed at survival and regeneration or, alternatively, they undergo degeneration and die. Previous reports have shown that at the initial stages of the response to axonal injury, polyamines are essential for neuronal survival and can accelerate functional recovery. In this study we examined the ability of exogenous polyamines to accelerate regeneration following crush of the pre- or postganglionic sympathetic nerves of the superior cervical ganglion in adult rats. We found that early treatment with polyamines after pre- or postganglionic nerve crush, accelerated the reappearance of choline acetyltransferase activity in the superior cervical ganglion, and of [3H]norepinephrine uptake in the iris, respectively. Functional recovery from eyelid ptosis was also accelerated. We conclude that treatment with polyamines can enhance regeneration of peripheral sympathetic neurons.  相似文献   
26.
BACKGROUND: Tourette syndrome (TS) is a chronic disorder characterized by motor and vocal tics. Previous studies reported a substantial lag period between disease onset and diagnosis ranging from 3 to 11.9 years. AIMS: To determine the lag period and factors associated with diagnosis delay of TS. METHODS: All files of 185 children with TS attending one neuropediatric unit in Jerusalem were reviewed. Lag time between disease onset, according to DSM criteria, and diagnosis was determined and the contributions of the disease course, comorbidities and epidemiological factors were assessed. RESULTS: A relatively short lag to diagnosis following the onset of diagnosable TS was documented (mean 13.2+/-15.9 months, median 6 months). A relatively longer gap was associated with older age at TS onset (r=0.161, p<0.05) and vocal tics as the first manifestation rather than motor or combined motor and vocal tics (mean=20.3+16.3 months vs 11.9+16.5 and 12.6+15.2, respectively, p<0.05). A relatively shorter gap was associated with tic severity (r=0.13, p<0.05) and presence of comorbid obsessive-compulsive disorder (OCD) (9.5+14.7 months vs. 14.1+16 without OCD, p<0.05). CONCLUSIONS: Lag time to diagnosis is relatively short in our population. Factors associated with a shorter lag (early age of TS onset, motor tics as the first manifestation, greater tics severity and the presence of OCD) may be perceived as disruptive, prompting patient and families to seek medical care. Conversely, vocal tics as the first manifestation, associated with a longer lag, may be misdiagnosed as features of common pediatric conditions, thus delaying diagnosis.  相似文献   
27.
OBJECTIVE: To assess whether the influenza vaccination of community-dwelling, diabetic, elderly individuals is associated with reduced rates of hospitalization and death. RESEARCH DESIGN AND METHODS: In this outcome-research study, we compared mortality and hospitalization rates of 15,556 patients aged >or=65 years followed using a diabetes registry in a large health maintenance organization to that of 69,097 members not suffering from chronic disease who were considered as a reference group. The study outcomes included all-cause death and hospitalization in internal medicine or geriatric wards for any reason over winter and summer (control) periods. RESULTS: Vaccination rates were 48.8 and 42.0% among patients with diabetes and the reference population, respectively. Influenza vaccination was associated with a 12.3% reduction in hospitalization rates for patients with diabetes compared with 23.0% in the reference group (P = 0.08). The reduction in hospitalization rates was similar in both sexes among patients with diabetes. In addition, there was a significant reduction in mortality for the vaccinated group of patients with diabetes when compared with the nonvaccinated group except for female patients aged >or=85 years. CONCLUSIONS: The study results support the use of influenza vaccine among an elderly population. However, there does not appear to be an additional benefit for patients with diabetes.  相似文献   
28.
Ab's to the alpha-chain of the IL-2 receptor (anti-CD25) are used clinically to achieve immunosuppression. Here we investigated the effects of DNA vaccination with the whole CD25 gene on the induction of rat adjuvant arthritis. The DNA vaccine protected the rats and led to a shift in the cytokine profile of T cells responding to disease target antigens from Th1 to Th2. The mechanism of protection was found to involve the induction of an antiergotypic response, rather than the induction of anti-CD25 Ab's. Antiergotypic T cells respond to activation molecules, ergotopes, expressed on syngeneic activated, but not resting, T cells. CD25-derived peptides function as ergotopes that can be recognized by the antiergotypic T cells. Antiergotypic T cells taken from control sick rats did not proliferate against activated T cells and secreted mainly IFN-gamma. In contrast, antiergotypic cells from CD25-DNA-protected rats proliferated against activated T cells and secreted mainly IL-10. Protective antiergotypic T cells were found in both the CD4+ and CD8+ populations and expressed alpha/beta or gamma/delta T cell receptors. Antiergotypic alpha/beta T cells were MHC restricted, while gamma/delta T cells were MHC independent. Thus, CD25 DNA vaccination may induce protection from autoimmunity by inducing a cytokine shift in both the antiergotypic response and the response to the antigens targeted in the disease.  相似文献   
29.
30.
Neuropsychological functioning of 30 siblings of children with autism (AU-S), 28 siblings of children with mental retardation of (MR-S), and 30 siblings of children with developmental language delay (DLD-S) was compared. Two siblings, both AU-S, received diagnoses of pervasive developmental disorder (PDD). More siblings with cognitive disabilities were found in DLD-S than in AU-S. However, these differences disappeared after excluding diagnosed siblings or after accounting for family membership. In sum, despite the elevated incidence of PDD among AU-S, the neuropsychological functioning of the remaining siblings did not convey specific characteristics related to the genetic risk associated with autism, in contrast to the cognitive functioning of the DLD-S, which did reflect a genetic risk.  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