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   690篇
  免费   70篇
耳鼻咽喉   12篇
儿科学   23篇
妇产科学   46篇
基础医学   105篇
口腔科学   29篇
临床医学   68篇
内科学   122篇
皮肤病学   22篇
神经病学   78篇
特种医学   18篇
外科学   51篇
综合类   1篇
预防医学   55篇
眼科学   64篇
药学   26篇
肿瘤学   40篇
  2023年   8篇
  2022年   11篇
  2021年   22篇
  2020年   11篇
  2019年   17篇
  2018年   32篇
  2017年   20篇
  2016年   29篇
  2015年   24篇
  2014年   33篇
  2013年   45篇
  2012年   41篇
  2011年   38篇
  2010年   22篇
  2009年   26篇
  2008年   32篇
  2007年   30篇
  2006年   29篇
  2005年   33篇
  2004年   24篇
  2003年   24篇
  2002年   26篇
  2001年   10篇
  2000年   8篇
  1999年   12篇
  1998年   6篇
  1997年   3篇
  1996年   3篇
  1995年   5篇
  1994年   4篇
  1992年   5篇
  1991年   6篇
  1990年   5篇
  1989年   4篇
  1988年   4篇
  1987年   5篇
  1986年   5篇
  1985年   8篇
  1984年   10篇
  1980年   3篇
  1979年   8篇
  1977年   5篇
  1975年   3篇
  1973年   5篇
  1972年   5篇
  1914年   2篇
  1912年   2篇
  1908年   2篇
  1904年   3篇
  1901年   5篇
排序方式: 共有760条查询结果,搜索用时 0 毫秒
1.
This study related clinical assessments of the severity of mandibular asymmetry with computerized measurements, obtained by digitizing mandibular outlines from standardized facial photographs. Four ratios were calculated: area (size), compactness (shape), perimeter (length of outline), and moment (center of area). When comparing clinical severity with computer assessment, significant correlations were observed; those for area and compactness were the highest. Sixteen patients subsequently underwent corrective surgery, and their ratios were used to relate the degree of improvement to the original severity of the asymmetry. The posttreatment ratios were also used to audit the outcome, comparing the patients' scores as a group with results previously obtained from patients with normal symmetry and mild asymmetry. Posttreatment outcomes were significantly different from the normal outline group but were comparable with outcomes of patients with mild mandibular asymmetry. The system provided a sensitive, noninvasive method of assessing treatment change and could be useful in providing an objective means of quantifying treatment outcomes.  相似文献   
2.
Murdoch Eaton DG, Wertheim D, Oozeer R, Dubowitz LMS, Dubowitz V. Reversible changes in cerebral activity associated with acidosis in preterm neonates. Acta Paediatr 1994;83:486–92. Stockholm. ISSN 0803–5253
Computerized online EEG monitoring in ventilated preterm infants less than 32 weeks' gestation enabled evaluation of the effect of acidosis on cerebral function. All episodes of acidosis were found to be associated with changes in the levels of cerebral activity. In 21 of the 32 episodes, EEG activity returned to pre-acidosis levels after therapeutic intervention. The duration of EEG abnormality was related to the severity of acidosis. However, the time to recovery of the EEG after therapeutic procedures was not related to duration of the EEG change.  相似文献   
3.
4.
10-Ethyl-10-deazaaminopterin (10-EDAM) is an analogue of methotrexate with improved preclinical anticancer activity, more selective entry, and greater conversion to polyglutamate forms in neoplastic cells. In this Phase I trial, we have treated 62 adults with advanced solid tumors, giving 10-EDAM i.v. on either a weekly x 3 schedule (35 patients) or a weekly schedule (27 patients). The dosage levels ranged from 5 to 120 mg/m2. The toxicity observed with 10-EDAM was qualitatively similar to that of methotrexate. Oral mucositis was the dose-limiting toxicity; diarrhea, skin rash, leukopenia, thrombocytopenia, and mild elevations of serum glutamic-oxaloacetic transaminase, prothrombin, and partial thromboplastin times were also observed, but were not dose limiting. A weekly dosage of 80 mg/m2 with escalation or attenuation in accordance with patient tolerance, or 100 mg/m2 weekly for 3 weeks, followed by a 2-week "rest period" are recommended for Phase II assessment. 10-EDAM produced partial remissions in three patients with non-small cell lung cancer and one patient with breast cancer lasting 6, 40+, 26+, and 15 months, respectively. Pharmacokinetic studies carried out at the 5, 30, and 100 mg/m2 dosage levels demonstrated the drug to have a triphasic disappearance from plasma. Elimination was independent of dose over the range tested, with mean plasma half-lives of: alpha = 12.9 min, beta = 1.5 h, and gamma = 11.9 h. Cumulative urinary excretion of the drug ranged from 13 to 55% of the administered dose (mean = 33%); 88% of the urinary drug appeared within the first 4 h following drug administration. The pharmacokinetic behavior of the first and second weekly dosages were consistent within a given patient. The metabolites 7-hydroxy-10-EDAM, and 10-ethyl-10-deaza-2,4-diamino-pteroic acid were demonstrated in the plasma and urine of treated patients. In studies of tissue homogenates from two patients with skin metastases, more extensive retention of the drug and of its polyglutamates was observed in the breast cancer metastases than in the metastases from a kidney cancer or in normal skin.  相似文献   
5.
The expression of intermediate filament proteins in human endometrial tissue was examined. Desmin was selectively expressed in decidualized stroma, as demonstrated by SDS-PAGE analysis and positive response with a monoclonal antibody specific for desmin in ELISA and in western blot analysis. The same monoclonal antibody specifically stained human decidual cells in decidualized endometrium (secretory endometrium) in formalin-fixed paraffin-embedded sections prepared from diagnostic curettage samples. Desmin was also detected in menstrual fluid. Therefore, desmin might serve as a biochemical and histochemical marker of human decidualized endometrium.  相似文献   
6.
PROBLEM: To examine the relationship between the concentration of uterine fluid human decidua-associated protein (hDP) 200, identified as a monoclonal rheumatoid factor, and different phases of the menstrual cycle. METHODS: Sequential measurements of hDP 200 concentration in uterine fluid were performed in 11 normal ovulatory women, aged 22–36 years. The samples were collected in early proliferative phase, late proliferative phase, periovulatory period, early secretory phase, and late secretory phase. RESULTS: Consistent fluctuations of hDP 200 levels in uterine fluid were found throughout the menstrual cycle. High levels were found during early proliferative phase and periovulatory period related to significantly lower levels during late proliferative and early luteal phases. CONCLUSION: There is menstrual phase dependent variation in the uterine fluid levels of hDP 200.  相似文献   
7.
Two enzyme-linked immunosorbent assays were established and compared for the estimation of plasma aldosterone. In the first method immobilized aldosterone-protein complexes on the ELISA plates compete with aldosterone to be determined for the binding of certain amount of anti-aldosterone antibodies. The sensitivity of this method depends on the protein carrier used to conjugate with aldosterone. In the second method, anti-aldosterone antibodies adsorbed on ELISA plates compete for binding of known amount of the enzyme-labeled aldosterone and aldosterone to be determined. The highly specific rabbit anti-aldosterone antibodies were obtained by injection of aldosterone-oxime thyroglobulin. The detection limit of aldosterone in both methods ranged between 2-20 pg. The proposed assays are suitable for the determination of aldosterone in biological fluids compared with other reported ELISA assays, as well as with RIA.  相似文献   
8.
In this novel enzyme-tagged immuoelectrochemical assay, disposable carbon felt discs serve both as electrodes and as the heterogeneous solid phase. Antibodies are immobilized on the carbon felt via a diaminoalkane-biotin-avidin-biotin bridge. Alkaline phosphatase is used as a label. Bound antibodies are monitored by following the electro-oxidation of aminophenol, produced enzymatically from p-amino-phenyl phosphate by the immobilized alkaline phosphatase at the electrode surface. A model system designed for determination of mouse IgG concentration yielded a calibration curve ranging from 10 pg/ml to 100 micrograms/ml. This assay can be performed rapidly and a single determination completed within 20 minutes. The system is useful also for rapid quantitation of a small number (approximately 80 organisms per ml) of bacteria.  相似文献   
9.
Analysis of consecutive emergency referrals to a community mental hospital over a 2-month period indicates that admissions are affected by a combination of demographic, clinical, and time factors. Both referrals and admissions were slightly higher in men. The mean age at referral was 44 years and of admitted patients was 30 years. Although married subjects constituted the largest group of applicants, widowers and divorced people were hospitalized more often. Both referral and admission rates were inversely correlated with education and employment. Most of the applicants came to the emergency ward accompanied by an escort. A lower rate of admissions was observed among those who came unescorted. The main indications for admission were acute psychosis and a nonspecific clinical state when the patient was defined as "dangerous to himself or to others." The family constituted the main source of referral. Peak referrals were during the morning hours, but admission rates were highest at night. Referrals decreased gradually from Sunday to Saturday, but the rate of admission was practically steady throughout the week. We conclude that the decisions for admitting a patient to a mental institute are based not only on pure psychiatric criteria, but also on an intuitive approach, in which the admitting physician's personal and emotional factors may play a role.  相似文献   
10.
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