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   1095篇
  免费   81篇
  国内免费   8篇
耳鼻咽喉   2篇
儿科学   35篇
妇产科学   27篇
基础医学   94篇
口腔科学   42篇
临床医学   94篇
内科学   268篇
皮肤病学   34篇
神经病学   68篇
特种医学   136篇
外科学   90篇
综合类   97篇
预防医学   25篇
眼科学   66篇
药学   57篇
  1篇
肿瘤学   48篇
  2022年   11篇
  2021年   23篇
  2020年   12篇
  2019年   14篇
  2018年   23篇
  2017年   13篇
  2016年   16篇
  2015年   25篇
  2014年   33篇
  2013年   34篇
  2012年   47篇
  2011年   44篇
  2010年   43篇
  2009年   50篇
  2008年   38篇
  2007年   44篇
  2006年   53篇
  2005年   24篇
  2004年   27篇
  2003年   29篇
  2002年   26篇
  2001年   29篇
  2000年   16篇
  1999年   14篇
  1998年   32篇
  1997年   53篇
  1996年   51篇
  1995年   35篇
  1994年   33篇
  1993年   39篇
  1992年   27篇
  1991年   13篇
  1990年   15篇
  1989年   25篇
  1988年   33篇
  1987年   14篇
  1986年   9篇
  1985年   11篇
  1984年   10篇
  1983年   11篇
  1982年   16篇
  1981年   14篇
  1980年   8篇
  1979年   5篇
  1978年   4篇
  1977年   6篇
  1976年   16篇
  1975年   9篇
  1973年   3篇
  1970年   1篇
排序方式: 共有1184条查询结果,搜索用时 15 毫秒
71.
There is disagreement among authors as to what criteria are most reliable in assessing postnatal fetal age. A comparison–for objectivity, accuracy, and frequency of use– of specific criteria was made using three independent examiners at different educational levels: a second-year medical student, a perinatal nurse practitioner, and a pediatrics resident. It was shown that trained examiners develop favorite criteria which differ among examiners and thus sacrifice accuracy; however, accurate assessment of fetal age can be accomplished by an examiner with minimum clinical knowledge.  相似文献   
72.
73.
The author believes that professional advice given the parents of a mongoloid infant determines their initial decision on institutionalization. Multidisciplinary counseling by the health team can help parents decide on a course of action that will prove satisfactory in the long run. Consultation should include health t e r n efforts to help parents work through the mourning process and presentation of a) an objective, comprehensive view of the child's condition, b) information on integrating a mongoloid into the family unit, and c) outside resources available to the parents. Deliberation with the parents to help them reach their own decision is essential.  相似文献   
74.
75.

Background

The Rh blood system is one of the most polymorphic and immunogenic systems known to humans. The expression of Rh blood group antigen is complex. The Rh D antigen is the most important of the antigens that constitute the Rh antigen system. In most cases, D antigen can easily be detected. However, due to variability of expression, weak forms antigen are encountered. The reactivity of weak D with antisera is variable and presents as a problem in blood banking.

Methods

A retrospective analysis for a five-year period was done. Blood samples that were negative for Rh D by immediate spin tube method were tested for weak D antigen by additional lab tests.

Result

Of 34932 serial Rh grouping tests done in our Blood Bank, the incidence of weak D Rh antigen was 0.189%. All these were confirmed by the antiglobulin test.

Conclusion

These patients present as a problem for the blood banker and a curiosity to the clinician. Although uncommon, all health care workers should be aware of this entity to avoid anti D alloimmunisation.Key Words: Weak D, Rh Blood Group  相似文献   
76.

Background

The present study was conducted to study the efficacy and toxicity profile of methotrexate chloroquine combination in treatment of active rheumatoid arthritis.

Methods

24 patients of rheumatoid arthritis confirming to revised American Rheumatism Association (ARA) criteria were studied prospectively for twenty months. Clinical evaluation was made every 3 months. Clinical disease variables measured at each visit were number of joints with swelling, number of joints with tenderness and pain, duration of morning stiffness and physician and patient assessment of disease activity. Blood counts, liver function tests and other adverse effects due to drugs were monitored every 2 months.

Results

10 patients demonstrated more than 50% improvement. 4 patients withdrew from study, 2 because of excessive nausea and vomiting and 2 because of noncompliance. Other side effects noted were hyperpigmentation, photosensitivity, skin rashes, raised transaminases and stomatitis.

Conclusion

Methotrexate chloroquine combination has good efficacy and toxicity profile. Gastrointestinal side effects are most common and usually responsible for the discontinuation of the drugs.Key Words: Rheumatoid arthritis, Methotrexate, Chloroquine, Efficacy, Toxicity  相似文献   
77.
78.
OBJECTIVE: Because celiac disease is a female-predominant disease we investigated the influence of gender on clinical manifestations of the disease in the United States. MATERIAL AND METHODS: Data were obtained on biopsy-proven adult patients with celiac disease from a database of patients seen between 1981 and 2001 in a University-based referral center. Z scores were calculated to adjust for age, ethnicity and gender using the National Health and Nutrition Examination Survey database as controls. RESULTS: The cohort consisted of 323 patients (211 F, 112 M). Men had a shorter duration of symptoms than women (p=0.006). There was no gender difference in the age at diagnosis or mode of presentation. Body mass index (BMI), mean hemoglobin and ferritin values were lower in women than in men, but the Z scores for these values were not significantly different, indicating that the differences are physiological. All lipid values were low (negative Z scores). Men had lower total cholesterol (162.0+/-46.5mg/dl) compared to women (181.0+/-40.0mg/dl), p=0.02 and lower Z scores (-1.10+/-1.1) compared to women (-0.71+/-0.9), p=0.04. Men had lower bone density T scores at the radius (p=0.07). Autoimmune diseases were present in 30.7% with a female to male ratio of 1:1, compared to the general population in which 3.2% have autoimmune diseases with a female predominance. CONCLUSIONS: Most gender differences in celiac disease are physiological. However, men have indirect evidence of greater malabsorption than females and have female-predominant associated diseases when they present with celiac disease.  相似文献   
79.
INTRODUCTION: Many patients with schizophrenia are exposed to serious health risks associated with their excess body weight. Evidence exists that even a moderate amount of weight loss may have significant health benefits. Thus, weight control in schizophrenia patients has become an important treatment goal. Although studies in the general population show that satisfaction with body weight is an important predictor for engagement in various weight loss measures, the perspective of schizophrenia patients has not been assessed. METHOD: Information on self-reported weight perception, desire to lose weight as well as weight loss attempts was obtained according to methods employed in the National Health and Nutrition Examination Survey, Cycle III (NHANES III). Body weight and height were measured and body mass index (BMI) was calculated. RESULTS: Perception of body weight and desire to lose weight were correlated to BMI. Both obese female and male subjects (BMI30) were aware of their weight status. However, whereas overweight females (BMI>25< or =29.9) accurately perceived themselves so, males in this category had difficulties perceiving themselves overweight, and consequently neither wanted to lose weight, nor tried to lose weight. As means of weight loss, caloric restriction (diet) was most frequently employed (by more than 80% of study subjects); yet only a third of study subjects (34.4%) engaged in the recommended combination of diet and exercise to lose weight. Questionable weight loss practices were also frequently employed, especially among women. CONCLUSIONS: Obese patients (BMI> or =30) were generally aware of their excess body weight and wanted to lose weight. Only non-obese, yet overweight males (BMI>25< or =29.9) did not perceive themselves as overweight and consequently did not try to lose weight. Weight loss practices did not always follow established recommendations. Especially women were likely to approach weight loss with questionably appropriate and unsafe methods.  相似文献   
80.
INTRODUCTION: Brain phospholipids are uniquely rich in polyunsaturated fatty acids (PUFAs). Most PUFAs such as alpha-linolenic acid 18:3(n-3), eicosapentaenoic acid 20:5(n-3), and docosahexaenoic acid 22:6(n-3) are essential and must be provided through the diet. PUFAs are also very sensitive to oxidative stress. Decreased essential fatty acid content has been observed in cell membranes of various tissue types of schizophrenia patients, including neural cell membranes. A number of mechanisms may account for these deficits, such as inadequate dietary supply or increased oxidation. It is known that patients with schizophrenia make poor dietary choices. However, whether their dietary fatty acid or antioxidant intake is insufficient and contributes to the observed deficiencies has not been assessed. METHODS: After obtaining informed consent, a 24-h diet recall was administered to elicit nutritional information in 146 outpatients with schizophrenia. Intake of fatty acids and antioxidants including vitamins A, C, and E was compared to U.S. population standards according to the National Health and Nutrition Examination Survey Cycle III (NHANES III) results. RESULTS: Saturated and polyunsaturated fatty acid (PUFA) intake was significantly higher in schizophrenia patients than in controls (p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