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   685篇
  免费   29篇
  国内免费   96篇
耳鼻咽喉   3篇
儿科学   36篇
妇产科学   4篇
基础医学   74篇
口腔科学   19篇
临床医学   105篇
内科学   160篇
皮肤病学   8篇
神经病学   57篇
特种医学   111篇
外科学   28篇
综合类   35篇
预防医学   44篇
眼科学   4篇
药学   84篇
肿瘤学   38篇
  2023年   7篇
  2022年   2篇
  2021年   13篇
  2020年   9篇
  2019年   10篇
  2018年   7篇
  2017年   8篇
  2016年   11篇
  2015年   6篇
  2014年   17篇
  2013年   34篇
  2012年   11篇
  2011年   10篇
  2010年   30篇
  2009年   28篇
  2008年   17篇
  2007年   63篇
  2006年   23篇
  2005年   26篇
  2004年   18篇
  2003年   11篇
  2002年   11篇
  2001年   22篇
  2000年   10篇
  1999年   13篇
  1998年   41篇
  1997年   39篇
  1996年   29篇
  1995年   29篇
  1994年   27篇
  1993年   39篇
  1992年   12篇
  1991年   9篇
  1990年   14篇
  1989年   28篇
  1988年   28篇
  1987年   16篇
  1986年   17篇
  1985年   14篇
  1984年   9篇
  1983年   4篇
  1982年   7篇
  1981年   4篇
  1980年   11篇
  1979年   2篇
  1978年   4篇
  1977年   7篇
  1976年   1篇
  1975年   1篇
  1935年   1篇
排序方式: 共有810条查询结果,搜索用时 62 毫秒
41.
BACKGROUND: To determine the factors associated with respiratory arrest in opiate overdoses (coma, pupillary miosis, respiratory depression, and response to naloxone) among injecting drug users in the Can Tunis quarter of Barcelona. METHODS: We ran a transversal observational study where all overdoses assisted between March, 2001 and June, 2002. After overdose treatment, data were collected using a standard questionnaire, including: patients' sociodemographic data, opiate and other substances' use prior to overdose, clinical signs and symptoms presented, and medical intervention received, by way of a standardised questionnaire. Logistic regression was used as a tool for analysis. RESULTS: Of 222 opiate overdose cases, 60.8% showed respiratory arrest. Of all risk factors tested, only prior abstinence heroin abstinence for 2 weeks or longer days (OR=1.893; p=0.04), and no previous consumption of benzodiazepines (OR:0.462; p=0.017), proved to have a statistically significant association with suffering a respiratory arrest. Concomitant use of alcohol, cocaine or methadone appeared not associated with suffering respiratory arrest in opiate overdose. CONCLUSIONS: The main risk factor for respiratory arrest in opiate overdoses was a prior abstinence period of more than 2 weeks. Benzodiazepines use was associated with absence of respiratory arrest in overdose cases. Alcohol or methadone use, as well as the use of larger quantities of heroin, was not associated with suffering respiratory arrest in opiate overdoses. A study of other factors, not included in this study, and that could interfere with our results, should be considered for their possible relationship to benzodiazepine use as well as to absence of respiratory arrest in overdose cases.  相似文献   
42.
43.
BACKGROUND: Because apomorphine is a dopamine agonist that acts on areas of the central nervous system believed to mediate penile erection, its use in erectile dysfunction (ED) has been investigated. However, it also produces nausea by dopamine-receptor stimulation of the chemotrigger zone in the brain. Therefore, a low plasma concentration, achieved rapidly, would be selective for the desired erectile response but would be below the dopamine threshold for nausea. OBJECTIVE: We evaluated the efficacy and tolerability of a dose-optimized regimen of a sublingual formulation of apomorphine (apomorphine SL) in the treatment of ED. METHODS: This was a multicenter, open-label, uncontrolled, Phase III dose-optimization study of apomorphine SL in heterosexual men with ED. The 2-week screening period, during which baseline severity of ED was determined using the International Index of Erectile Function, was followed by a 3-week dose-optimization period beginning at a dose of 2 mg. Patients were to make at least 2 attempts at intercourse per week throughout the study, placing 1 apomorphine tablet under the tongue beforehand. At the end of the first week, the dose could be increased to 3 mg at the discretion of the investigator; at the end of the second week, the dose could be increased to a maximum of 4 mg or decreased as needed. In the following 4-week treatment period, patients took their individual optimal doses. The primary efficacy variable was the percentage of attempts resulting in erections firm enough for intercourse, as assessed by investigators' review of data from patients' diaries. Secondary variables included the percentage of attempts resulting in successful intercourse, time to erection, and duration of erection. Information about adverse events, including their severity and relation to treatment, was determined on the basis of direct questioning, spontaneous reports, and review of patient diaries. RESULTS: The study enrolled 849 heterosexual men whose ages ranged from 31 to 78 years (mean, 58.1 years). They had a mean 5.7-year history of ED of varbus causes. ED was mild in 11.5% of the men, moderate in 23.8 c, and severe in 48.1%. When results of the last 8 attempts were pooled, representing the period during which patients were taking their optimal doses of apomorphine SL, the mean percentage of attempts resulting in erections firm enough for intercourse was 39.4%, compared with 13.1% at baseline; attempts resulting in intercourse increased from a mean of 12.7% at baseline to 38.3% with treatment. The average median time to erection was 23 minutes, and the average median duration of erection was 13 minutes. Nausea, the most common treatment-related adverse event (11.7%). was dose related and diminished with continued dosing. One patient had a single syncopal episode that was judged to be related to apomorphine SL. CONCLUSIONS: In the present study, a dose-optimization regimen of apomorphine SL-with dosing initiated at 2 mg and adjusted up to a maximum of 4 mg as needed-was effective and well tolerated in the treatment of ED, regardless of its cause or severity.  相似文献   
44.
Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested.  相似文献   
45.
高效液相色谱法测定寒痹停片中士的宁含量   总被引:6,自引:0,他引:6  
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。  相似文献   
46.
47.
48.
Over the past decades there has been an important increase in the incidence of dermatophytoses in humans as a result of contact with animals, although etiological agents can vary as can the animals transmitting the disease. A large-scale study was carried out in 220 farms raising rabbits for consumption. Most of the farms (85%) were located in the autonomous community of Catalonia (Spain). Mycological studies showed that 79.5% of the rabbits were infected with Trichophyton mentagrophytes var. granulosum. Microsporum canis was isolated in only two animals, which had been imported from France. Healthy animal carriers were detected in 3.2% of the apparently non-infected farms. T. mentagrophytes were also found in samples taken from rabbits' nests and from the sorrounding environment of the two infected farms.In a survey carried out among the staff responsible for the care of the animals, 77% of those working on infected farms suffered or had suffered dermatophytic lesions. This was confirmed in 8 out of 10 cases sampled. Attention is drawn to the high incidence of dermatophytoses in rabbits on farms and the importance of T. mentagrophytes as the etiological agent of tineas in people in close contact with infected animals.  相似文献   
49.

Purpose

The level of recommended physical activity (PA) is met less frequently by people from some ethnic minorities than others. We explored whether these differences in recommended PA between ethnic minority groups and the general population varied by domain and type of culturally-specific activity.

Methods

Participants were sampled from the population based SUNSET study and were from ethnic Dutch (n = 567), Hindustani-Surinamese (n = 370) and African-Surinamese (n = 689) descent. The validated SQUASH-questionnaire measured PA for the following domains: commuting, occupation, household, leisure time. Culturally-specific activities were added as extra question within the leisure time domain. The effect of each domain on ethnic differences in recommended PA prevalence was examined by odds-ratio (OR) analysis through recalculating recommended PA, while, in turn, excluding the contribution of each domain.

Results

In the ethnic Dutch population, more vigorous PA in commuting and leisure time was reported compared to the Surinamese groups. The Hindustani-Surinamese and African-Surinamese reported more walking as commuting activity, while the Dutch group reported cycling more frequently. Ethnic differences in recommended PA became smaller in both Surinamese groups compared with the Dutch after removing commuting activity, for example, in Hindustani-Surinamese men (OR = 0.92, 95%CI: 0.62-1.37 vs. OR = 1.33, 0.89-2.00) and women (OR = 1.61, 1.12-2.32 vs. OR = 2.03, 1.41-2.92). Removing occupational activity resulted in larger ethnic differences in both groups compared with the Dutch. Smaller effects were found for yoga and dancing, leisure time and household activities.

Conclusion

This study shows that differences in PA between ethnic minority groups and the general population vary according to the activity domain. The results indicate that including all relevant domains and activities is essential for assessment of ethnic differences in recommended PA.  相似文献   
50.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  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