全文获取类型
收费全文 | 18398篇 |
免费 | 1385篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 152篇 |
儿科学 | 682篇 |
妇产科学 | 367篇 |
基础医学 | 2713篇 |
口腔科学 | 320篇 |
临床医学 | 1876篇 |
内科学 | 4159篇 |
皮肤病学 | 246篇 |
神经病学 | 1961篇 |
特种医学 | 800篇 |
外国民族医学 | 3篇 |
外科学 | 2308篇 |
综合类 | 206篇 |
一般理论 | 7篇 |
预防医学 | 1162篇 |
眼科学 | 670篇 |
药学 | 838篇 |
中国医学 | 14篇 |
肿瘤学 | 1350篇 |
出版年
2021年 | 206篇 |
2019年 | 239篇 |
2018年 | 285篇 |
2017年 | 228篇 |
2016年 | 266篇 |
2015年 | 282篇 |
2014年 | 367篇 |
2013年 | 534篇 |
2012年 | 789篇 |
2011年 | 836篇 |
2010年 | 491篇 |
2009年 | 463篇 |
2008年 | 676篇 |
2007年 | 821篇 |
2006年 | 784篇 |
2005年 | 747篇 |
2004年 | 767篇 |
2003年 | 663篇 |
2002年 | 710篇 |
2001年 | 608篇 |
2000年 | 598篇 |
1999年 | 479篇 |
1998年 | 235篇 |
1997年 | 221篇 |
1996年 | 193篇 |
1995年 | 213篇 |
1994年 | 190篇 |
1993年 | 166篇 |
1992年 | 441篇 |
1991年 | 416篇 |
1990年 | 416篇 |
1989年 | 373篇 |
1988年 | 376篇 |
1987年 | 349篇 |
1986年 | 376篇 |
1985年 | 336篇 |
1984年 | 277篇 |
1983年 | 244篇 |
1982年 | 179篇 |
1981年 | 167篇 |
1980年 | 144篇 |
1979年 | 221篇 |
1978年 | 193篇 |
1977年 | 144篇 |
1976年 | 153篇 |
1975年 | 144篇 |
1974年 | 166篇 |
1973年 | 163篇 |
1972年 | 133篇 |
1971年 | 131篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
E Hollander C DeCaria R Gully A Nitescu R F Suckow J M Gorman D F Klein M R Liebowitz 《Psychiatry research》1991,36(1):1-17
To investigate the effect of fluoxetine on serotonergic sensitivity in obsessive-compulsive disorder (OCD), the partial serotonin agonist metachlorophenylpiperazine (mCPP) was compared to placebo under double-blind conditions in six patients with OCD before and during treatment with fluoxetine. Readministration of oral mCPP (0.5 mg/kg) after at least 12 weeks of fluoxetine treatment did not increase obsessive-compulsive (OC) symptoms, in contrast to exacerbation of OC symptoms produced by mCPP before treatment. Chronic fluoxetine treatment resulted in a significant increase in prolactin and cortisol response to mCPP. This may be accounted for, however, by substantially increased plasma mCPP levels during fluoxetine treatment. Chronic fluoxetine treatment diminished the behavioral sensitivity to mCPP and did not diminish, but may have partially normalized, the neuroendocrine response to mCPP in patients with OCD. These adaptive homeostatic effects may reflect fluoxetine's antiobsessional mechanism. 相似文献
62.
T A Klein D G Young S R Telford R Kimsey 《Journal of the American Mosquito Control Association》1987,3(2):154-164
Lutzomyia vexator is an efficient experimental vector of Plasmodium mexicanum, infecting 69.2% (9/13) of the Sceloporus undulatus lizards with as few as one bite. Sporozoites were present in the salivary glands by day 6.5 postfeed and infective by day 8 postfeed at 27 degrees C. The prepatent period was relatively long, ranging from 23 to 40 days for bite-induced infections and appears to be related to the number of sporozoites injected. The acute phase of the infection is initially exponential and rapid. All lizards (6) that were not sacrificed, died of fulminating infections from 13 to 56 days after parasites were seen in the blood films. Gametocytes from 2 experimentally infected lizards were infective to L. vexator during the course of the acute infection. The majority of P. mexicanum parasites were in erythrocytes of Sc. undulatus. Exoerythrocytic forms were observed in circulating lymphocytes and thrombocytes, lymphocytes of spleen and bone marrow, and endothelial cells of brain capillaries. 相似文献
63.
A J Klein 《Ear and hearing》1989,10(1):50-57
Hearing aids with signal processors use advanced circuitry to enhance speech recognition in noise. The effectiveness of these processors has not been well established. The purpose of this study was to evaluate performance on a speech recognition in noise task for listeners wearing a Zeta signal processor aid with the processor turned on and with the processor turned off. In addition, comparisons were made to performance while unaided and aided with a conventional hearing aid. A simple adaptive procedure and a psychometric function were the procedures used. Results for normal-hearing subjects indicate performance was usually better without a hearing aid. Performance when aided was similar for the processor on and the conventional aid. Performance in both of these conditions was clearly better than with the signal processor off. Although results for the hearing-impaired subjects varied widely, there was a trend for better performance with the conventional aid and with the signal processor on than for the signal processor off condition. 相似文献
64.
65.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
66.
67.
Objective . To describe the importance of migraine in Santiago, Chile, by analyzing its prevalence, clinical features and impact by age, gender and socioeconomic status. Methods . In 1993, a representative sample of 1,540 adults of the province of Santiago were interviewed using a standard questionnaire. A total of 1,385 (89.9%) subjects responded to the survey. Initially, a designated member of each household responded to the questionnaire. Subsequently, each household member with headaches was asked to respond to questions about severity, frequency, location, duration, associated symptoms and impact in work and social activities of their most frequent headaches. Migraine diagnoses were determined in accordance with the International Headache Society (IHS) criteria of 1988. Results. Recurrent headaches in the past year were found in 516 (36.82%) respondents, 145 (28.1%) males and 371 (71.9%) females. Total prevalence of migraine was found to be 7.3% (95%, CI 5.9–8.6); 11.9% (95% CI 9.6–14.2) in females and 2.0% (95% CI 0.9–3.0) in males. Overall, migraine constituted 19.6% (101/516) of all headaches reported in this sample. The prevalence did not vary significantly by age groups or socioeconomic status (SES). Migraine with aura had an overall prevalence of 3.5% (CI 0.8–7.1), and was significantly more frequent in females. In 60–70% of cases the attacks lasted 2–6 h and the frequency was 3.3 and 3.4 per month in females and males respectively. Both males and females reported significantly high percentages of attacks during work. Conclusions . Migraine prevalence in a sample of adults of Santiago is similar to that reported in previous studies using IHS criteria. Women of all socioeconomic levels are at an increased risk. 相似文献
68.
69.
P J Sulak G S Letterie C C Hayslip C C Coddington T A Klein 《Fertility and sterility》1987,48(3):493-494
In two patients with apparent PTO, as diagnosed by HSG and laparoscopy, tubal patency was restored by hysteroscopic cannulation of the tubal ostia, followed by direct lavage. Tubal resection and reanastomosis/reimplantation may not be necessary for all patients with apparent PTO. 相似文献
70.
Inversion lateral ankle trauma: differential diagnosis, review of the literature, and prospective study 总被引:1,自引:0,他引:1
M Perlman D Leveille J DeLeonibus R Hartman J Klein R Handelman E Schulz S Wertheimer 《The Journal of foot surgery》1987,26(2):95-135
This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate. 相似文献