全文获取类型
收费全文 | 865篇 |
免费 | 45篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 51篇 |
妇产科学 | 9篇 |
基础医学 | 76篇 |
口腔科学 | 18篇 |
临床医学 | 108篇 |
内科学 | 246篇 |
皮肤病学 | 5篇 |
神经病学 | 22篇 |
特种医学 | 163篇 |
外科学 | 37篇 |
综合类 | 14篇 |
预防医学 | 55篇 |
眼科学 | 37篇 |
药学 | 53篇 |
中国医学 | 2篇 |
肿瘤学 | 47篇 |
出版年
2024年 | 2篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 12篇 |
2017年 | 9篇 |
2016年 | 4篇 |
2015年 | 7篇 |
2014年 | 12篇 |
2013年 | 19篇 |
2012年 | 12篇 |
2011年 | 12篇 |
2010年 | 38篇 |
2009年 | 38篇 |
2008年 | 18篇 |
2007年 | 33篇 |
2006年 | 17篇 |
2005年 | 19篇 |
2004年 | 15篇 |
2003年 | 16篇 |
2002年 | 25篇 |
2001年 | 27篇 |
2000年 | 23篇 |
1999年 | 23篇 |
1998年 | 57篇 |
1997年 | 50篇 |
1996年 | 46篇 |
1995年 | 44篇 |
1994年 | 47篇 |
1993年 | 34篇 |
1992年 | 17篇 |
1991年 | 24篇 |
1990年 | 21篇 |
1989年 | 35篇 |
1988年 | 26篇 |
1987年 | 20篇 |
1986年 | 24篇 |
1985年 | 15篇 |
1984年 | 8篇 |
1983年 | 8篇 |
1982年 | 11篇 |
1981年 | 8篇 |
1980年 | 11篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 10篇 |
1976年 | 7篇 |
1975年 | 3篇 |
1969年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有946条查询结果,搜索用时 0 毫秒
1.
2.
P. M. J. Zelissen H. P. F. Koppeschaar D. W. Erkelens J. H. H. Thijssen 《Clinical endocrinology》1991,35(4):369-372
OBJECTIVE: To test the hypothesis that the hyperendorphinaemia in obesity originates from outside the pituitary. DESIGN: Intravenous administration of corticotrophin-releasing hormone (CRH) after overnight suppression with 2 mg of dexamethasone in normal-weight controls and in obese subjects before and after weight reduction. PATIENTS: Eleven obese females, age (mean +/- SEM) 30 +/- 2.1 years, body mass index (BMI) 41.2 +/- 1.9 kg/m2. Eight normal-weight females served as controls, age 26 +/- 2.1 years, BMI 21.4 +/- 0.5 kg/m2. Five obese subjects were also studied after weight loss of 18.4 +/- 1.0% of original weight. MEASUREMENTS: Plasma beta-endorphin, ACTH and cortisol. Cortisol production rate in 24-hour urine. Basal (without dexamethasone suppression) plasma beta-endorphin levels. RESULTS: Basal (without dexamethasone suppression) beta-endorphin levels were 7.7 +/- 0.8 pmol/l in the obese and 3.8 +/- 0.5 pmol/l in the control subjects (P less than 0.005). The degree of suppression of beta-endorphin after dexamethasone was similar in the obese (23.2 +/- 3.7%) and in the control subjects (28.2 +/- 0.12%). Administration of CRH following dexamethasone suppression resulted in a small but significant increase of plasma beta-endorphin in both obese (from 1.55 +/- 0.12 to 2.32 +/- 0.28 pmol/l) and control subjects (from 0.98 +/- 0.24 to 1.69 +/- 0.33 pmol/l). The groups did not differ regarding this response, nor regarding the release of ACTH and cortisol after CRH. Cortisol production rate was higher (P less than 0.001) in the obese (68.7 +/- 3.3 mumol/24 h) than in the controls (40.0 +/- 3.0 mumol/24 h). No correlation between cortisol production rate and basal beta-endorphin levels was found. Weight loss appeared to have no influence on cortisol production rate, basal beta-endorphin levels, or on the responses to dexamethasone or CRH. CONCLUSIONS: Plasma beta-endorphin in obese subjects can be affected by manipulations of the hypothalamic-pituitary-adrenocortical axis; the hypothesis that the hyperendorphinaemia of obesity originates from outside the pituitary cannot be confirmed. 相似文献
3.
4.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
5.
N-l-leucyl-doxorubicin and vinblastine-isoleucinate can be considered as relatively non-toxic prodrugs from doxorubicin and vinblastine, respectively. A comparative analysis was carried out of the anti-tumour activity of the four compounds as well as vintriptol in four human ovarian cancer xenografts different in histology, growth rate and chemosensitivity. Injections were given i.v. weekly twice into mice bearing well-established s.c. tumours. At equitoxic doses, the amount of drug administered for N-l-leucyl-doxorubicin and vinblastine-isoleucinate was respectively 3-fold and 2-fold higher than the doses of the parent compound. N-l-leucyl-doxorubicin induced a growth inhibition > 50% in three out of four human ovarian cancer lines. The anti-tumour effects obtained were significantly better (P < 0.01) than in the case of doxorubicin. Vinblastine-isoleucinate studied in two of these lines could induce a growth inhibition of > 50%. This prodrug appeared slightly less effective than vinblastine. Insignificant growth inhibition (< 50%) was obtained by vintriptol. 相似文献
6.
PL Macken FRACO FRACS CJ Pavlin FRCS R Tuli MD GE Trope PhD FRCS 《Clinical & experimental ophthalmology》1995,23(3):217-220
Background: Spherophakia is an uncommon diagnosis. This is the first case report of spherophakia evaluated by ultrasound biomicroscopy.
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy. 相似文献
7.
8.
9.
10.
The development of both adenocarcinoma of the jejunum and in situ squamous carcinoma of the oesophagus in an adult coeliac patient is described. Good evidence that adenocarcinoma of jejunum occurs more frequently in patients with coeliac disease has recently become available though this association has been suggested for some time. While oesophageal carcinoma has long been associated with coeliac disease, in situ carcinoma of oesophagus has not been previously described in these circumstances. We feel that the risk of this complication, as calculated from published series, warrants a screening programme for oesophageal malignancy in adult coeliacs. 相似文献