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   255篇
  免费   31篇
  国内免费   3篇
耳鼻咽喉   4篇
儿科学   4篇
妇产科学   4篇
基础医学   38篇
口腔科学   4篇
临床医学   21篇
内科学   54篇
皮肤病学   4篇
神经病学   3篇
特种医学   9篇
外科学   90篇
综合类   7篇
预防医学   16篇
药学   10篇
肿瘤学   21篇
  2023年   6篇
  2022年   9篇
  2021年   9篇
  2020年   8篇
  2019年   14篇
  2018年   13篇
  2017年   5篇
  2016年   26篇
  2015年   8篇
  2014年   10篇
  2013年   6篇
  2012年   18篇
  2011年   21篇
  2010年   10篇
  2009年   9篇
  2008年   8篇
  2007年   7篇
  2006年   8篇
  2005年   12篇
  2004年   10篇
  2003年   10篇
  2002年   4篇
  2001年   4篇
  2000年   12篇
  1999年   4篇
  1998年   5篇
  1997年   2篇
  1996年   3篇
  1995年   3篇
  1992年   2篇
  1991年   4篇
  1990年   4篇
  1989年   4篇
  1987年   3篇
  1986年   1篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1979年   1篇
  1972年   1篇
  1967年   1篇
  1966年   1篇
排序方式: 共有289条查询结果,搜索用时 15 毫秒
1.
Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  相似文献   
2.
M He  A S Kang  M Hamon  A S Humphreys  M Gani    M J Taussig 《Immunology》1995,84(4):662-668
The heavy chain variable region (VH) and the kappa light chain of the anti-progesterone monoclonal antibody (mAb) DB3, have been expressed as a single-chain three-domain polypeptide, designated VH/K, and secreted into the periplasmic space of Escherichia coli (E. coli). The linker sequence was derived from the VH-CH1 elbow region. The C kappa domain provides a sensitive detection tail for Western blotting and enzyme-linked immunosorbent assay (ELISA). Periplasmic extracts of transformed E. coli contained material that bound progesterone and related steroids with similar specificity and affinity to DB3, and displayed the DB3 idiotype and kappa chain epitopes. Reference to the crystal structure of DB3 suggests that all the characteristics of the combining site interaction with steroids are retained in the bacterially expressed material. Western blotting demonstrated material with a molecular weight equivalent to three domains after reduction, but six domains in the unreduced state, suggesting that the VH/K polypeptide is assembled in the periplasm as a disulphide-bridged dimer. The VH/K construct provides a novel route to expression of antibody combining sites in E. coli for antibody engineering.  相似文献   
3.
Glomus vagale are rare vascular tumours of the paraganglion cells of the vagus nerve, and they usually occur in the carotid space. Tumours can be familial, multicentric, malignant but rarely hormonally active. A rare case is reported of glomus vagale presenting as a supraclavicular mass.  相似文献   
4.
5.
6.
Apolipoprotein A-I and B concentrations were measured in 502 patients undergoing diagnostic cardiac catheterization to assess the predictive power of apolipoproteins B and A-I to discriminate between patients with coronary artery disease and those with normal coronary arteries as defined by coronary arteriography. The strength of the associations was compared with that of the associations between traditional risk factors (eg, smoking status, cholesterol levels) and coronary artery disease. The study population consisted of 154 women (mean age, 62.9 years) and 348 men (mean age, 59.6 years). The apolipoprotein A-I concentration averaged (+/- SD) 124 +/- 25 mg/dL and the apolipoprotein B concentration, 98 +/- 24 mg/dL. In all cases, the apolipoprotein measures showed a larger univariate difference between the "normal" (no coronary artery disease) group (66 patients) and the group with coronary artery disease (436 patients) than did the corresponding standard lipoprotein measures. The variable with the strongest association with coronary artery disease was the ratio of apolipoprotein A-I to apolipoprotein B, followed by apolipoprotein B level. These findings were confirmed using logistic regression, adjusting for other coronary artery disease risk factors. Fasting status did not affect apolipoprotein A-I or B concentrations. We conclude that the use of apolipoprotein A-I and B concentrations gives additional information to that supplied by lipoprotein measures to help predict the presence of coronary artery disease. Since traditional lipid measures may be changed by a meal, apolipoproteins A-I and B might be more useful measures when the fasting status of a patient is in question.  相似文献   
7.
Vitamin D deficiency is common and may contribute to osteopenia, osteoporosis and falls risk in the elderly. Screening for vitamin D deficiency is important in high-risk patients, especially for patients who suffered minimal trauma fractures. Vitamin D deficiency should be treated according to the severity of the deficiency. In high-risk adults, follow-up serum 25-hydroxyvitamin D concentration should be measured 3–4 months after initiating maintenance therapy to confirm that the target level has been achieved. All patients should maintain a calcium intake of at least 1,000 mg for women aged ≤ 50 years and men ≤ 70 years, and 1,300 mg for women > 50 years and men > 70 years.  相似文献   
8.
ObjectiveAssessment of plasma matrix metalloproteinase-9 (MMP-9) and Doppler markers of increased left ventricular (LV) filling pressure may be added to risk stratify patients with ischemic cardiomyopathy (IC). Therefore, we aimed at investigating the value of plasma MMP-9 and restrictive filling pattern (RFP) in IC patients.MethodsEighty-eight consecutive patients hospitalized for heart failure (LV ejection fraction  40%) due to IC were enrolled. A complete M-mode and two-dimensional echo-Doppler examination were performed. Patients were defined as having RFP if they had a mitral E wave deceleration time < 150 ms. Plasma MMP-9 and N-terminal protype-B natriuretic peptide levels were assessed at the time of the index echocardiogram. The end point was all-cause mortality or hospitalization for worsening HF. Follow-up period was 25 ± 17 months.ResultsMedian value of MMP-9 was 714 ng/ml. On univariate analysis, a number of measurements predicted the composite end point: NYHA class > 2, RFP, MMP-9 > 60.5 ng/ml, LV ejection fraction < 27%, anemia, pulmonary pressure  35 mm Hg, N-terminal protype-B natriuretic peptide > 1742 pg/ml, and glomerular filtration rate < 60 ml/min/1.73 m2. Independent variables of outcome were anemia (HR = 1.9, p = 0.031), and the combination of plasma MMP-9 and RFP (HR = 3.2, p = 0.004). On Kaplan–Meier survival curves, patients with elevated MMP-9 levels and RFP had the lowest event-free survival rate (log-rank: 29.0, p < 0.0001). The net reclassification improvement showed a significant increase in the prediction model when elevated MMP-9 and RFP were added to the base model that included clinical, biochemical and echocardiographic parameters (p < 0.0001).ConclusionMMP-9 levels and RFP have an incremental predictive value to risk classify IC patients.  相似文献   
9.
10.
IntroductionAcute general surgical units (AGSUs) are changing the way in which acute appendicitis is managed. In the AGSU at John Hunter Hospital, some patients wait more than 48 hours from admission to undergo an appendicectomy, usually because they are not unwell enough to precipitate an operation before that time. We analysed this subgroup of appendicectomy patients to determine how effectively they are being managed and how this might be improved.MethodsA retrospective review of prospectively collected data was conducted of all patients who received an appendicectomy while admitted under the AGSU at John Hunter Hospital in the five years between January 2009 and December 2013.ResultsA total of 1,039 appendicectomies were performed in the study period, with 81 patients (7.8%) waiting >48 hours for their operation (delayed appendicectomy group). Overall, the negative appendicectomy (NA) rate was 21.6%; the NA rate in delayed appendicectomies was 50.62% and a non-therapeutic operation occurred in 47% of this group (n=38). No significant difference was found in the incidence of perforation/gangrenous appendicitis between patients having surgery in <48 hours and the delayed appendicectomy groups (11.2% vs 9.9%, p=0.85). A combination of negative diagnostic imaging result, a normal white cell count and normal C-reactive protein (ie a negative ‘triple test’) was the best predictor of a negative appendicectomy (p=0.0158, negative predictive value: 0.91, 95% confidence interval: 0.59–0.99), in the delayed appendicectomy group.ConclusionsIn the delayed appendicectomy group, the incidence of perforation/gangrenous appendicitis was not significantly different from that found in patients having appendicectomy performed sooner. However, the NA and non-therapeutic operation rates were unacceptably high. An appendix triple test can improve diagnostic accuracy significantly without an unacceptable rise in the rates of perforation/gangrenous appendicitis.  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