全文获取类型
收费全文 | 58367篇 |
免费 | 2346篇 |
国内免费 | 425篇 |
专业分类
耳鼻咽喉 | 433篇 |
儿科学 | 1223篇 |
妇产科学 | 1083篇 |
基础医学 | 7573篇 |
口腔科学 | 978篇 |
临床医学 | 4414篇 |
内科学 | 13378篇 |
皮肤病学 | 791篇 |
神经病学 | 5099篇 |
特种医学 | 2375篇 |
外国民族医学 | 3篇 |
外科学 | 9092篇 |
综合类 | 1951篇 |
一般理论 | 37篇 |
预防医学 | 3266篇 |
眼科学 | 833篇 |
药学 | 3911篇 |
28篇 | |
中国医学 | 144篇 |
肿瘤学 | 4526篇 |
出版年
2024年 | 49篇 |
2023年 | 441篇 |
2022年 | 987篇 |
2021年 | 1990篇 |
2020年 | 1176篇 |
2019年 | 1772篇 |
2018年 | 2673篇 |
2017年 | 1764篇 |
2016年 | 2295篇 |
2015年 | 2443篇 |
2014年 | 2959篇 |
2013年 | 3790篇 |
2012年 | 4518篇 |
2011年 | 3791篇 |
2010年 | 2926篇 |
2009年 | 2565篇 |
2008年 | 3256篇 |
2007年 | 3257篇 |
2006年 | 2963篇 |
2005年 | 2939篇 |
2004年 | 2628篇 |
2003年 | 2143篇 |
2002年 | 1807篇 |
2001年 | 339篇 |
2000年 | 433篇 |
1999年 | 421篇 |
1998年 | 433篇 |
1997年 | 338篇 |
1996年 | 285篇 |
1995年 | 230篇 |
1994年 | 212篇 |
1993年 | 233篇 |
1992年 | 188篇 |
1991年 | 151篇 |
1990年 | 176篇 |
1989年 | 160篇 |
1988年 | 165篇 |
1987年 | 134篇 |
1986年 | 154篇 |
1985年 | 130篇 |
1984年 | 121篇 |
1983年 | 78篇 |
1982年 | 103篇 |
1981年 | 76篇 |
1980年 | 78篇 |
1979年 | 49篇 |
1978年 | 50篇 |
1976年 | 52篇 |
1971年 | 46篇 |
1968年 | 58篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Baha’ N. Noureddin Christiane E. Al-Haddad Ziad Bashshur Bared Safieh-Garabedian 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(6):750-752
Background The objective was to measure the plasma concentrations of thymulin and nerve growth factor (NGF) in a group of patients with primary open angle glaucoma (POAG) and compare them with age- and sex-matched normal controls.Methods Twenty-eight patients newly diagnosed with POAG who were not undergoing treatment were compared with the same number of age- and sex-matched healthy controls. Blood samples were drawn into heparinized tubes and plasma samples were collected for the determination of the concentrations of thymulin and NGF, using specific enzyme-linked immunosorbent assay (ELISA). The Student’s t test was used to perform the necessary statistical analysis of the results.Results Seventeen women and 11 men were enrolled in each of the two groups (study and control), with a mean age of 63.7 (SD 10.3) years in the former and 63.3 (SD 9.6) years in the latter. There was a highly significant (p<0.001) elevation in the thymulin levels in POAG patients compared with the control group. However, no significant difference was observed when comparing the plasma NGF levels.Conclusion This is the first report to measure plasma thymulin levels in glaucoma patients. The significant results point the possible role of this immunomodulator in the pathogenesis of primary open angle glaucoma. The potential role of NGF seems to be less likely. These findings warrant further investigation. 相似文献
12.
o. goetze a. b. nikodem j. wiezcorek † m. banasch h. przuntek † t. mueller † w. e. schmidt & d. woitalla † 《Neurogastroenterology and motility》2006,18(5):369-375
Predictors of gastric emptying (GE) in patients with idiopathic Parkinson's disease (PD) of a solid and liquid meal are not well defined. For measurement of GE 80 patients with PD were randomly assigned to receive either a solid meal (250 kcal) containing 13C-octanoate (n = 40) or a liquid meal (315 kcal) with 13C-acetate (n = 40). All patient groups were off medication affecting motility and were matched for age, gender, body mass index, disease duration and severity, using Unified Parkinson's Disease Rating Scale (UPDRS). Gastric emptying was compared with a healthy control group (n = 40). Multiple regression analysis was used to determine predictors of gastric emptying. Exactly 88% and 38% of PD patients had delayed GE of solids and liquids respectively. Solid and liquid emptying was similar in women and men. There were no differences in GE in PD patients < 65 years of age when compared with patients > or = 65 years. Multiple regression analysis showed that motor handicaps such as rigour and action tremor are independent predictors of solid GE (r = 0.68, P < 0.001). The severity of motor impairment, but not any other neurological symptom, as assessed by UPDRS is associated with gastroparesis in PD and solid emptying is more likely to be delayed. 相似文献
13.
S. V. Terent’eva E. N. Komarova T. N. Sapozhnikova A. T. Teplyakov E. A. Ivanovskaya T. I. Andreeva 《Pharmaceutical Chemistry Journal》2006,40(12):694-696
A rapid procedure for determining angiotensin II in the blood by inverse voltammetry using a TA-2 device (Tekhnoanalit Company,
Tomsk) with a graphite electrode has been developed. The results of analyses using the proposed technique agree with the clinical
data. The rapid analytical procedure favors optimization of cardiotropic drug therapy.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 12, pp. 54–56, December, 2006. 相似文献
14.
Bruno Ferrari Antonio Pezzuto Lorenzo Barusi Francesco Coppola 《Gynecological endocrinology》2006,22(6):289-296
The aim of the present study was to investigate the effect of gonadotropin-releasing hormone (GnRH) antagonists (GnRH-ant) on follicular fluid (FF) insulin-like growth factor-I (IGF-I) and FF vascular endothelial growth factor (VEGF) levels. Sixty women undergoing assisted reproduction were randomized and assigned to two different GnRH analog regimens: GnRH agonist (GnRH-a) and GnRH-ant. FF VEGF and FF IGF-I concentrations were significantly increased in the patients treated with GnRH-ant (p < 0.001). In the same patients we observed a statistically significant reduction in serum luteinizing hormone (LH) and estradiol (E2) levels (p < 0.001 and p < 0.05, respectively), FF E2 and FF androstenedione levels (p < 0.05 and p < 0.001, respectively), as well as a reduction in the number of pregnancies although this was not statistically significant. In the GnRH-ant group, FF VEGF levels were positively correlated with FF IGF-I levels, and both were negatively correlated with serum LH levels. The increase in FF IGF-I and FF VEGF levels in women treated with GnRH-ant could be explained by a deleterious follicular environment in response to profound suppression of LH and E2 levels. 相似文献
15.
Anorectal function in the solitary rectal ulcer syndrome 总被引:8,自引:6,他引:2
Nigel R. Womack F.R.C.S. Professor Norman S. Williams M.S. John H. Holmfield Mist John F. Morrison Ph.d. 《Diseases of the colon and rectum》1987,30(5):319-323
The anorectal function of nine patients with solitary rectal ulcer syndrome (SRUS) (5 F: 4 M, median age, 27 (range, 19–41
years) and nine control subjects (5 F: 4 M, median age, 47 (35–66)P<0.01) has been investigated by a new technique that radiologically visualizes the anorectum during voiding of a semisolid
contrast medium, while simultaneously measuring intrarectal pressure and anal sphincter EMG activity. A degree of rectal prolapse
was demonstrated in eight of the SRUS patients; six of these lesions were clinically occult. Abnormal failure of the anal
sphincter to relax on voiding was present in seven of the SRUS patients. These abnormalities resulted in the SRUS patients
requiring a greater increase in intrarectal pressure (median, 100 cm water) to void than the control subjects (median, 65
cm water,P<0.01). This combination of high intrarectal pressure and rectal prolapse during straining seems to be the cause of SRUS
This work was supported by a grant from the Medical Research Council. 相似文献
16.
17.
18.
19.
FDA’S Perspectives on Cardiovascular Devices 总被引:1,自引:0,他引:1
Eric A. Chen Sonna M. Patel-Raman Kathryn O’Callaghan Matthew G. Hillebrenner 《Journal of cardiovascular translational research》2009,2(2):143-146
The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a
review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices
and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the
health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug
& Cosmetic Act, §903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 ). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization
therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA’s review of extensive preclinical
bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer
to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device
performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different
marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular
device in a U.S. clinical trial. 相似文献