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   430篇
  免费   13篇
  国内免费   16篇
儿科学   32篇
妇产科学   1篇
基础医学   37篇
口腔科学   8篇
临床医学   62篇
内科学   84篇
皮肤病学   3篇
神经病学   8篇
特种医学   98篇
外科学   28篇
综合类   32篇
预防医学   28篇
眼科学   1篇
药学   28篇
中国医学   1篇
肿瘤学   8篇
  2022年   1篇
  2021年   2篇
  2020年   1篇
  2019年   3篇
  2018年   3篇
  2017年   3篇
  2016年   4篇
  2015年   8篇
  2014年   12篇
  2013年   16篇
  2012年   14篇
  2011年   11篇
  2010年   27篇
  2009年   16篇
  2008年   8篇
  2007年   15篇
  2006年   8篇
  2005年   6篇
  2003年   6篇
  2002年   13篇
  2001年   8篇
  2000年   10篇
  1999年   14篇
  1998年   24篇
  1997年   27篇
  1996年   25篇
  1995年   18篇
  1994年   18篇
  1993年   15篇
  1992年   1篇
  1991年   4篇
  1990年   6篇
  1989年   21篇
  1988年   16篇
  1987年   12篇
  1986年   8篇
  1985年   6篇
  1984年   4篇
  1983年   8篇
  1982年   3篇
  1981年   7篇
  1980年   10篇
  1979年   2篇
  1978年   4篇
  1977年   2篇
  1976年   4篇
  1975年   2篇
  1932年   1篇
  1925年   1篇
  1924年   1篇
排序方式: 共有459条查询结果,搜索用时 15 毫秒
91.
92.
Aim:  The classical combination of abdominal pain, vomiting, rectal blood loss and a palpable abdominal mass is only present in a minority of children with intussusception. Neurological signs and symptoms have been described, but are not a well understood phenomenon. We performed a retrospective study to ascertain the frequency and nature of these symptoms and to describe the characteristics of the patients presenting in this atypical way.
Methods:  The records of 58 children presenting with intussusception from 2003 to 2008 were reviewed for abdominal and neurological signs and symptoms, duration of symptoms and effectiveness of treatment.
Results:  In 10 out of 58 patients (17%), one or more neurological symptoms were recorded at presentation, with lethargy being the most frequent, followed by hypotonia and fluctuating consciousness. The patients with neurological abnormalities were significantly younger and presented with a shorter duration of symptoms. Therapy was more invasive, although not statistically significant, in this patient category.
Conclusion:  Intussusception should be considered in the differential diagnosis in young children presenting with lethargy, hypotonia and/or sudden alterations of consciousness even in the absence of the classical symptoms of intussusception.  相似文献   
93.
94.
The absence of a vertebral pedicle, regardless of location, always merits careful consideration. There are a variety of disease states in addition to intrinsic mechanisms which may influence the development of the spine and hence potentiate pedicular absence. Each of these diseases or processes must be considered when confronted by a missing pedicle. This paper will identify and briefly discuss the most common conditions resulting in pedicular absence.  相似文献   
95.
The aim of the study was to investigate the effect of a protein restricted diet on renal function and growth of children with chronic renal failure. In a multicentre prospective study 56 children (aged 2-18 years) with chronic renal failure were randomly assigned to the protein restricted (0.8-1.1 g/kg/day) or the control group. All children were followed up by the same paediatrician and dietitian. After a follow up period of three years there was no significant difference in glomerular filtration rate between children on a protein restricted diet and children of the control group. There was no significant difference in weight with respect to height and height SD score between the protein restricted and the control group. Compliance with the protein restricted diet, as indicated by the prospective diet diaries and the serum urea:creatinine ratio, was good. This study shows that children with chronic renal failure do not benefit from a protein restricted diet.  相似文献   
96.
Corrosion of lead sheet used for structural radiation protection in the Princess Alexandra Hospital radiology department has been identified. The corrosion is thought to have been caused by organic acid vapours released from oregon timber wall panelling. Non-destructive testing (NDT) and X-ray transmission measurements were used to define the extent and severity of damage, and subsequently to provide the data necessary for estimation of staff and public radiation doses. Although radiation dose limits have not been exceeded, corrective actions including structural modifications and staff information sessions have been undertaken.  相似文献   
97.
PurposeIndividuals with type 2 diabetes (T2DM) are at increased risk of cardiovascular disease, including heart failure (HF). In patients with T2DM elevated serum concentrations of the N-terminal fragment of pro-B-type natriuretic peptide (NT-proBNP) correlate with cardiovascular morbidity and mortality. We aimed to identify predictors of increased serum NT-proBNP levels in patients with T2DM.MethodsThe study included 185 patients with T2DM treated with either oral antidiabetic agents (49.7%) or insulin (17.8%), or both (32.5%). We divided the patients into two groups: with high (>200 pg/mL) and low (≤200 pg/mL) NT-proBNP concentrations.ResultsWe found differences between the patients with high and low NT-proBNP levels including age, prevalence of dyslipidemia and HF, history of previous myocardial infarction (MI), heart rate, hemoglobin level, platelet count, creatinine, urea and uric acid concentrations, use of beta-blockers, loop diuretics, metformin and insulin. In a multivariate analysis metformin was a negative predictor of increased NT-proBNP concentration. Age, history of HF and decreased estimated glomerular filtration rate (eGFR) were positive predictors. We found no correlation between NT-proBNP serum concentration and insulin treatment or history of coronary artery disease or MI.ConclusionMetformin correlates with lower concentrations of NT-proBNP in patients with T2DM.  相似文献   
98.
Background: Currently, it is difficult to predict the prognosis of patients exhibiting stage II or stage III colorectal cancer (CRC) and to identify those patients most likely to benefit from aggressive treatment. The current study was performed to examine the clinicopathological significance of CD44 and CD44v6 protein expression in these patients. Study design: We retrospectively investigated 187 consecutive patients who underwent surgery with curative intent for stage II to III CRC from 2007 to 2013 in the Beijing Civil Aviation Hospital. CD44 and CD44v6 protein expression levels were determined using immunohistochemistry and compared to the clinicopathological data. Results: Using immunohistochemical detection, CD44 expression was observed in 108 (57.75%) of the CRC patients; and its detection was significantly associated with greater invasion depth, lymph node metastasis, angiolymphatic invasion, and a more advanced pathological tumor-lymph node-metastasis (TNM) stage. CD44v6 expression was observed in 135 (72.19%) of the CRC patients; and its expression was significantly associated with a poorly differentiated histology, greater invasion depth, lymph node metastasis, angiolymphatic invasion, and a more advanced pathological TNM stage. Expression of CD44v6 was higher than that of CD44 in stage II and stage III sporadic CRC. Conclusion: CD44v6 is a more useful marker for predicting a poor prognosis in stage II and stage III sporadic CRC as compared to CD44.  相似文献   
99.
100.
We investigated the prophylactic and therapeutic efficacy of an intravenous (IV) formulation of zanamivir in a macaque infection model for highly pathogenic influenza A (H5N1) virus. Antiviral efficacy was dose-dependent, with no reduction in viral load observed at 2 mg/kg, but a significant reduction observed at 10 mg/kg (p=0.039) and at 20 mg/kg in the combined prophylactic and therapeutic groups (p=0.049) with both prophylaxis (commencing 12 h before infection) and therapy (commencing 4 h after infection) showing similar reductions in viral load. Combined gross pathology and microscopic pneumonia scores in the treated animals relative to untreated controls were significantly reduced at 10 mg/kg (p=0.02) and at 20 mg/kg in the prophylaxis group (p=0.02), but were not significant in the treatment group (p=0.145). In this new animal model for evaluation of influenza antivirals, despite variability observed between individual animals, IV zanamivir showed evidence of efficacy against highly pathogenic H5N1 virus.  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