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   236篇
  免费   27篇
  国内免费   5篇
耳鼻咽喉   1篇
儿科学   16篇
妇产科学   7篇
基础医学   34篇
口腔科学   10篇
临床医学   34篇
内科学   43篇
皮肤病学   3篇
神经病学   17篇
特种医学   26篇
外科学   16篇
综合类   29篇
预防医学   13篇
眼科学   2篇
药学   7篇
肿瘤学   10篇
  2023年   1篇
  2022年   2篇
  2021年   6篇
  2019年   1篇
  2018年   4篇
  2017年   1篇
  2016年   3篇
  2015年   3篇
  2014年   10篇
  2013年   5篇
  2012年   6篇
  2011年   8篇
  2010年   5篇
  2009年   10篇
  2008年   10篇
  2007年   9篇
  2006年   10篇
  2005年   7篇
  2004年   7篇
  2003年   6篇
  2002年   8篇
  2001年   6篇
  2000年   4篇
  1999年   5篇
  1998年   18篇
  1997年   14篇
  1996年   14篇
  1995年   8篇
  1994年   10篇
  1993年   10篇
  1992年   9篇
  1991年   4篇
  1990年   3篇
  1989年   3篇
  1988年   8篇
  1987年   5篇
  1986年   6篇
  1985年   1篇
  1984年   2篇
  1983年   4篇
  1982年   1篇
  1981年   4篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1975年   3篇
  1974年   1篇
排序方式: 共有268条查询结果,搜索用时 15 毫秒
31.
We report 8 infants with immediate hypersensitivity reactions to foods (milk, egg, or peanut), occurring at the first-known exposure. Each developed symptoms within the first hour, but these generally settled within 2 hours. Sensitisation to the food concerned was demonstrated by positive immediate allergen skin prick tests in every case. Symptoms experienced included irritability, erythematous rash, urticaria, angio-oedema, vomiting, rhinorrhoea, and cough. Five infants were being followed prospectively and 4 were clinically tolerant of the food by age 16 months. The most likely route of sensitisation was via breast milk. None of the infants experienced similar reactions while being breast fed, suggesting that the reaction was dose dependent. As 5 out of a group of 80 infants being followed prospectively developed an immediate reaction at their first known exposure to a food, this appeared to be a not uncommon presentation of food hypersensitivity in infancy.  相似文献   
32.
33.
Culture media used for human in-vitro fertilization (IVF) can be contaminated with bacterial endotoxins. All five tested types of commercially available albumin, sometimes used as a protein supplement to IVF media, were shown to contain endotoxins in varying concentrations. Endotoxins are suspected to cause embryo fragmentation and low pregnancy rates in human IVF. However, human sperm viability and the IVF of mouse oocytes and subsequent culture of the zygotes were shown to be unaffected by relatively high endotoxin concentrations. Therefore these techniques cannot be used as quality control assays to detect endotoxins in the IVF culture media.  相似文献   
34.
35.
OBJECTIVE. As lipoprotein(a) is an independent risk factor for the development of coronary heart disease we determined the effect on serum lipid and lipoprotein(a) levels of dietary fibre and of treatment with insulin in patients with diabetes mellitus type II. METHODS. Twelve type II diabetic patients (mean age 62 (SD 10) yrs, body mass index 25.8 (SD 3.5) kg/m2), all treated with oral antidiabetic agents, were studied in a randomised cross-over trial, in which they used breads meals prepared with guar gum (a mean of 11.2 g guar per day) for 3 months in comparison with normal high-fibre bread. Fifteen other patients (age 70 (8), BMI 27.4 (5.6) kg/m2) poorly controlled on oral hypoglycaemic agents, were treated with insulin. RESULTS. The guar treatment of the 12 patients resulted in lower total cholesterol (5.24 vs 5.7 mmol/l, p less than 0.1) and LDL cholesterol (3.77 vs 4.33 mmol/l, p less than 0.001) in comparison with normal high-fibre bread. Lipoprotein(a) levels were not different (76 vs 82 mg/l). Insulin therapy in the 15 other patients decreased HbA1c levels after 6 months from 11.0 to 7.7% (p less than 0.001), total cholesterol from 6.8 to 6.1 mmol/l (p less than 0.05), and LDL cholesterol from 4.4 to 4.1 mmol/l (p less than 0.05). Lp(a) decreased only slightly in 11/15 patients, from 491 to 441 mg/l (p = 0.07). CONCLUSION. Neither the use of the dietary fibre guar nor improved metabolic control with insulin therapy lowered elevated lipoprotein(a) levels in type II diabetic patients.  相似文献   
36.

Background

A retrospective assessment of contrast enhanced computed tomography (CECT) scan findings in histopathologically proven cases of carcinoma of the gallbladder (GB) was performed to review its role in diagnosis, staging and assessment of surgical resectability.

Methods

All the patients had been subjected to a standardised abdominal helical computed tomography scan. Orally administered iodinated contrast was used for opacification of bowel and dynamic intravenous injection of non-ionic iodinated contrast for studying the lesional enhancement and vascular structures.

Results

The presence of focal or diffuse mass lesions in the gallbladder fossa, infiltration of a liver and second part of duodenum were the most reliable diagnostic features in carcinoma gallbladder. Regional spread was better delineated on CT scan as compared with ultrasonography.

Conclusion

CT scan is an effective method for evaluating, characterizing and detecting the spread of GB carcinomas.Key Words: Gall Bladder, Carcinoma, Computed Tomography  相似文献   
37.
Constitutional pure red cell aplasia (CPRCA) is a syndrome of failed erythropoiesis usually diagnosed within the first year of life. Four patients with CPRCA received transplants with marrow from their HLA- identical, mixed lymphocyte culture-nonreactive siblings. All patients were resistant to corticosteroid therapy and were dependent on regular red cell transfusions for at least 5 years. Three patients were conditioned with procarbazine, antithymocyte globulin, cyclophosphamide, and busulfan, and one was conditioned with antithymocyte serum, cyclophosphamide, and busulfan. Three patients promptly had successful engraftments with establishment of donor hematopoiesis. One patient initially rejected his graft but received a successful retransplant. All patients are currently alive with Karnofsky performance scores of 100 and normal erythropoiesis of donor origin. Despite a history of multiple transfusions, bone marrow transplantation is a potentially curative therapy for patients with CPRCA.  相似文献   
38.
Ortega  JA; Shore  NA; Dukes  PP; Hammond  D 《Blood》1975,45(1):83-89
An in vitro marrow culture assay designed to measure erythropoietic capability was used to ascertain the presence of an inhibitor in the sera of patients with congenital hypoplastic anemia (CHA). Marrow cells from nine anemic CHA patients responded to the stimulatory effect of exogenous erythropoietin (EPO) by an increase in heme synthesis in the presence of normal serum. The effect on heme synthesis was less than that observed with normal marrow cells. CHA serum inhibited heme synthesis by both normal and CHA marrow cells. It is concluded that an in-inhibitor of erythropoiesis is present in serum from CHA patients. This inhibitor most likely blocks the EPO-sensitive stem cell receptor sites, causing decreased response to the hormone.  相似文献   
39.
OBJECTIVES: The aim of the study was to determine whether serum concentrations of neuron-specific enolase (NSE) and S100-B in mild traumatic brain injury (MTBI) patients are higher than in serum of healthy controls. MATERIAL AND METHODS: Blood samples from 104 MTBI patients were taken shortly after the trauma for measurement of S-100B and NSE in serum. In 92 healthy persons these markers were also measured. Marker concentrations in serum of patients and controls were compared. In the patient group the relation between serum-marker concentrations and clinical symptoms and signs, that occurred shortly after the traumatic event, were evaluated. RESULTS: Median NSE concentration was only slightly higher in patients (9.8 microg/l; 10 to 90 percentile range 6.9 to 14.3 microg/ l) than in controls (9.4 microg/l; 6.3 to 13.3 microg/l). Median S-100B concentration was significantly higher in patients (0.25 microg/l; 0.00 to 0.68 microg/l) than in controls (0.02 microg/l; 0.00 to 0.13 microg/l). An association was found between S-100B concentrations and vomiting in patients. CONCLUSIONS: S-100B is a useful marker for brain damage in MTBI patients and seems to be associated with the presence of vomiting after the trauma.  相似文献   
40.
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  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