全文获取类型
收费全文 | 16544篇 |
免费 | 2189篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 114篇 |
儿科学 | 714篇 |
妇产科学 | 328篇 |
基础医学 | 2466篇 |
口腔科学 | 474篇 |
临床医学 | 1773篇 |
内科学 | 3700篇 |
皮肤病学 | 160篇 |
神经病学 | 1189篇 |
特种医学 | 668篇 |
外科学 | 2567篇 |
综合类 | 458篇 |
一般理论 | 15篇 |
预防医学 | 1684篇 |
眼科学 | 191篇 |
药学 | 1455篇 |
中国医学 | 6篇 |
肿瘤学 | 814篇 |
出版年
2021年 | 207篇 |
2020年 | 151篇 |
2019年 | 204篇 |
2018年 | 241篇 |
2017年 | 189篇 |
2016年 | 165篇 |
2015年 | 215篇 |
2014年 | 342篇 |
2013年 | 465篇 |
2012年 | 676篇 |
2011年 | 686篇 |
2010年 | 382篇 |
2009年 | 361篇 |
2008年 | 670篇 |
2007年 | 752篇 |
2006年 | 698篇 |
2005年 | 702篇 |
2004年 | 682篇 |
2003年 | 690篇 |
2002年 | 684篇 |
2001年 | 614篇 |
2000年 | 641篇 |
1999年 | 561篇 |
1998年 | 266篇 |
1997年 | 217篇 |
1996年 | 230篇 |
1995年 | 197篇 |
1994年 | 221篇 |
1993年 | 200篇 |
1992年 | 452篇 |
1991年 | 423篇 |
1990年 | 422篇 |
1989年 | 364篇 |
1988年 | 346篇 |
1987年 | 316篇 |
1986年 | 317篇 |
1985年 | 344篇 |
1984年 | 268篇 |
1983年 | 209篇 |
1982年 | 166篇 |
1981年 | 170篇 |
1979年 | 235篇 |
1978年 | 173篇 |
1977年 | 189篇 |
1976年 | 144篇 |
1975年 | 162篇 |
1974年 | 202篇 |
1973年 | 203篇 |
1972年 | 134篇 |
1971年 | 132篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
C Finke C Juge M Goumaz O Kaiser R Davies A G Burger 《Journal of endocrinological investigation》1987,10(2):157-162
The induction of mixed function hepatic oxygenases by rifampicin is known to increase the metabolic clearance rate (MCR) of T4. By performing T3 and rT3 kinetics we have shown that rifampicin also increases the MCR of T3 and rT3. Using the fall of serum T4 during TSH suppression as an indirect marker of the production rate (PR) of T4, we have demonstrated that there was no major change in monodeiodination nor any shift to either 5'- or 5-monodeiodination. Rifampicin stimulates in mice the mixed function hepatic oxygenases. However, we were unable to increase hepatic deiodinase activity (deiodinase type I) in this species. It is therefore possible that the increased MCR of T4 in man is not mediated by an increased conversion rate either. As mixed function hepatic oxygenases are known to increase hepatic conjugation it is suggested that rifampicin increases the biliary excretion of iodothyronine conjugates. 相似文献
123.
124.
Time course of cellular infiltration in the nasal mucosa during the immediate allergic reaction 总被引:2,自引:0,他引:2
S Lozewicz E Gomez S Chalstrey D Gatland R J Davies 《International archives of allergy and applied immunology》1991,95(2-3):273-277
In 23 patients with allergic rhinitis, biopsies of the nasal mucous membrane were taken at one of the following times after challenge of one nostril with allergen: 0 (baseline) (n = 7), 1/2 h (n = 6), 1 h (n = 5), and 2 h (n = 5). In the nostril stimulated by allergen there was a transient early phase influx of eosinophils while the numbers of stainable mast cells decreased, probably due to their degranulation. In the contralateral unstimulated nostril, there was no change in numbers of eosinophils but the numbers of stainable mast cells decreased. These results support the proposed role in allergic rhinitis of the mast cell and eosinophil, and suggest that the eosinophil may be a rapidly mobilized effector cell. 相似文献
125.
Microinjections of various alpha 1-adrenoceptor agonists including phenylephrine and phenylpropanolamine into the paravenricular hypothalamic nucleus (PVN) suppress food intake in rats, suggesting that this receptor type might act in opposition to previously identified facilatory PVN alpha 2-adrenoceptors in the modulation of feeding. In the present experiments, we examine the effects on food and water intake of intra-PVN as well as systemic injection of cirazoline, a highly potent alpha 1-adrenoceptor agonist. In Experiment 1, intra-PVN microinjection of cirazoline (0, 3, 6, 12 and 24 nmol) suppressed food intake (ED50 = 23.4 nmol) without significant effects on water intake. In Experiment 2, systemic injection of cirazoline (0, 0.05, 0.1, 0.2, 0.4 mg/kg) also markedly suppressed food intake (ED50 = 0.05 mg/kg i.p.), with a less potent action on water intake (ED50 = 0.22 mg/kg i.p.). The results of this study as well as our previous investigations strongly support the notion that alpha 1-adrenoceptors within rat PVN act to reliably suppress food intake. 相似文献
126.
Electrosurgery techniques have been used in dentistry as an aid to soft tissue management for nearly 60 years. However, it was not until the late 1960s that the principles of electrosurgery were understood and improved equipment became available. Part 1 of the two-part series covered the theory behind using this technique. Part 2 will now discusses the clinical applications. 相似文献
127.
128.
Efficacy of a single pretransplant donor-specific transfusion and cyclosporin A administered 24 to 48 hours before one-haplotype-mismatched living related donor kidney transplant. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Annals of surgery》网站下载免费的PDF全文](/ch/ext_images/free.gif)
C B Davies J W Alexander B R Cofer M R First T J Schroeder 《Annals of surgery》1992,215(6):618-25; discussion 626
During the 7-year period from March 1984 to June 1991, 86 haploidentical living related kidney recipients were entered into one of three donor-specific transfusion (DST) and cyclosporine treatment protocols: (1) Multiple pretransplant DSTs with cyclosporine begun after transplant, n = 34; (2) Multiple pretransplant DSTs with cyclosporine begun pretransplant, n = 31; and (3) a single DST 24 to 48 hours before transplant with intravenous cyclosporine initiated after the transfusion, n = 21. Triple immunosuppression (prednisone, azathioprine, and cyclosporine) was continued in all groups after transplant. The 1-year patient (97%, 97%, and 93%, p = not significant) and graft (91%, 90%, and 87%, p = not significant) survival were similar for the three groups. No differences were seen in the incidence of rejection at 1 year (61%, 45%, and 60%, p = not significant) or in the incidence of infectious complications (26%, 42%, and 47%, p = not significant). It is concluded that a single DST given 24 to 48 hours before operation followed by pretransplant cyclosporine is as effective as classic DST conditioning of recipients using either pretransplant or post-transplant cyclosporine. The single DST protocol has the advantage of not eliminating any donors because of sensitization and was less costly and easier to administer. 相似文献
129.
G R Goldberg A M Prentice H L Davies P R Murgatroyd 《European journal of clinical nutrition》1988,42(2):137-144
The FAO/WHO/UNU recommendations for energy requirements assume that the energy cost of sleep is equal to the basal metabolic rate (BMR). We have tested the validity of this assumption by analysing overnight and BMR measurements made by whole-body indirect calorimetry. Data from 80 healthy subjects measured on a total of 246 occasions have been used. In a subgroup of 40 normal lean subjects the mean ratio of overnight metabolic rate (Overnight MR): BMR was 0.95 (range 0.85 - 1.02, s.d. 0.04). The mean ratio of lowest sleeping metabolic rate (Lowest SMR): BMR was 0.88 (range 0.83 - 0.96, s.d. 0.04). Ratios of Overnight MR: BMR were not significantly affected by different levels of exercise on the preceding day. This ratio was significantly higher for subjects who were obese, late pregnant or attached to ECG electrodes. With the exception of the late pregnant subjects these groups had the same Lowest SMR:BMR ratios as the normal lean subjects, indicating that the higher Overnight MR was caused by disturbed sleep. The data suggest that the use of BMR to estimate overnight energy expenditure would introduce an average overestimate of approximately 5 per cent during the actual hours of sleep, but that when applied over 24 h the error becomes negligible. 相似文献
130.
Toxicity of diethyltoluamide-containing insect repellents 总被引:1,自引:0,他引:1