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   592篇
  免费   56篇
  国内免费   5篇
耳鼻咽喉   8篇
儿科学   23篇
妇产科学   14篇
基础医学   44篇
口腔科学   11篇
临床医学   84篇
内科学   129篇
皮肤病学   21篇
神经病学   17篇
特种医学   97篇
外科学   60篇
综合类   22篇
预防医学   49篇
眼科学   8篇
药学   20篇
肿瘤学   46篇
  2023年   6篇
  2021年   15篇
  2020年   8篇
  2019年   7篇
  2018年   15篇
  2017年   16篇
  2016年   12篇
  2015年   19篇
  2014年   30篇
  2013年   42篇
  2012年   12篇
  2011年   15篇
  2010年   32篇
  2009年   19篇
  2008年   20篇
  2007年   22篇
  2006年   16篇
  2005年   9篇
  2004年   8篇
  2003年   4篇
  2002年   11篇
  2001年   14篇
  2000年   7篇
  1999年   14篇
  1998年   27篇
  1997年   32篇
  1996年   29篇
  1995年   17篇
  1994年   19篇
  1993年   12篇
  1992年   10篇
  1991年   2篇
  1990年   6篇
  1989年   9篇
  1988年   8篇
  1987年   8篇
  1986年   8篇
  1985年   10篇
  1984年   9篇
  1983年   5篇
  1982年   13篇
  1981年   7篇
  1980年   11篇
  1979年   5篇
  1978年   6篇
  1977年   8篇
  1976年   6篇
  1975年   5篇
  1973年   3篇
  1970年   2篇
排序方式: 共有653条查询结果,搜索用时 31 毫秒
91.
Color Doppler imaging (CDI) can demonstrate the relative direction and velocity of blood flow in color, superimposed on a conventional gray-scale ultrasound image that depicts stationary tissue. Twenty-five infants were studied with portable CDI in the coronal, sagittal, and axial planes. Bilateral antegrade flow was noted in the anterior, middle, and posterior cerebral arteries in all patients. Multiplanar CDI can image flow in the circle of Willis and its tributaries and branches.  相似文献   
92.
A technique for simultaneous bilateral biplane arteriography of the abdomen, pelvis, and lower extremities is described. The biplane views provided clinically significant information in approximately 40% of cases.  相似文献   
93.
Bile was excluded from the gastrointestinal tract of 5 dogs with Heidenhain pouches by total external biliary fistulas. After a major portion of the jejunum and the ileum was resected Heidenhain pouch secretions increased in all instances. The results indicate that the increase in gastric secretion which regularly follows small-bowel resection is independent of the presence or absence of bile in the gastrointestinal tract.Supported by Grant AM-7750 from the US Public Health Service.The opinions expressed in this publication are those of the authors and not necessarily those of the US Air Force Medical Service.  相似文献   
94.
Ultrasound findings in hepatitis   总被引:1,自引:0,他引:1  
  相似文献   
95.
96.

Background:

It is not known whether cardiovascular disease (CVD) risk level is related to knowledge of the leading cause of death of women or heart attack symptoms.

Hypothesis:

Women with higher CVD risk estimated by Framingham Risk Score (FRS) or metabolic syndrome (MS) have lower CVD knowledge.

Methods:

Women visiting primary care clinics completed a standardized behavioral risk questionnaire. Blood pressure, weight, height, waist size, fasting glucose, and lipid profile were assessed. Women were queried regarding CVD knowledge.

Results:

Participants (N = 823) were Hispanic women (46%), non‐Hispanic white (37%), and non‐Hispanic black (8%). FRS was determined in 278: low (63%), moderate (29%), and high (8%); 24% had ≥3 components of MS. The leading cause of death was answered correctly by 54%, heart attack symptoms by 67%. Knowledge was lowest among racial/ethnic minorities and those with less education (both P< 0.001). Increasing FRS was inversely associated with knowing the leading cause of death (low 72%, moderate 68%, high 45%, P = 0.045). After multivariable adjustment, moderate/high FRS was inversely associated with knowing symptoms (moderate odds ratio [OR] 0.52, 95% confidence interval [CI]: 0.28‐0.98; high OR 0.29, 95% CI: 0.11–0.81), but not the leading cause of death. MS was inversely associated with knowing the leading cause of death (P< 0.001) or heart attack symptoms (P = 0.018), but not after multivariable adjustment.

Conclusions:

Women with higher FRS were less likely to know heart attack symptoms. Efforts to target those at higher CVD risk must persist, or the most vulnerable may suffer disproportionately, not only because of risk factors but also inadequate knowledge. Clin. Cardiol. 2011 DOI: 10.1002/clc.22092 This work was supported in part by the US Department of Health and Human Services (1HHCWH05003‐01‐11); Arlene and Joseph Taub Foundation, Paterson, New Jersey; Edwina and Charles Adler Foundation; and by Columbia University's CTSA grant, UL1‐RR024156 from the NCRR/NIH. The authors have no other funding, financial relationships, or conflicts of interest to disclose.  相似文献   
97.
The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis is becoming an important part of glioblastoma classification. Besides the well-known cell cycle-related circuitries that are associated with glioblastoma onset and development, new insights may be derived by looking at pathways involved in regulation of epigenetic phenomena and cellular metabolism, which may both be highly deregulated in cancer cells. We evaluated if in glioblastoma patients the high grade of malignancy could be associated with aberrant expression of some genes involved in regulation of epigenetic phenomena and lipid metabolism. We measured the mRNA levels of ZFP57, TRIM28, CPT1A, CPT1B, and CPT1C in a cohort of 80 patients divided in two groups: grade II and grade IV. We evidenced that high grade glioblastoma is associated with increased level of ZFP57, a protein involved in gene imprinting, and aberrant expression of CPT1A and CPT1C, regulators of fatty acid oxidation. Our study may pave the way to identify new markers that could be potentially useful for diagnosis and/or prognosis of glioblastoma.  相似文献   
98.
Rationale, aims and objectives Drug‐eluting coronary stents (DES) rapidly dominated the marketplace in the United States after approval in 2003, but utilization rates were initially lower among African American patients. We assess whether racial differences persisted as DES diffused into practice. Methods Medicare claims data were used to identify coronary stenting procedures among elderly patients with acute coronary syndromes (ACS). Regression models of the choice of DES versus bare mental stent controlled for demographics, ACS type, co‐morbidities and hospital characteristics. Diffusion was assessed in the short run (2003–2004) and long run (2007), with the effect of race calculated to allow for time‐varying effects. Results The sample included 381 887 Medicare beneficiaries treated with stent insertion; approximately 5% were African American. Initially (May 2003–February 2004), African American race was associated with lower DES use compared to other races (44.3% versus 46.5%, P < 0.01). Once DES usage was high in all patients (March–December 2004), differences were not significant (79.8% versus 80.3%, P = 0.45). Subsequent concerns regarding DES safety caused reductions in DES use, with African Americans having lower use than other racial groups in 2007 (63.1% versus 65.2%, P < 0.01). Conclusions Racial disparities in DES use initially disappeared during a period of rapid diffusion and high usage rates; the reappearance of disparities in use by 2007 may reflect DES use tailored to unmeasured aspects of case mix and socio‐economic status. Further work is needed to understand whether underlying differences in race reflect decisions regarding treatment appropriateness.  相似文献   
99.
100.
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