全文获取类型
收费全文 | 997篇 |
免费 | 88篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 22篇 |
妇产科学 | 9篇 |
基础医学 | 131篇 |
口腔科学 | 72篇 |
临床医学 | 152篇 |
内科学 | 206篇 |
皮肤病学 | 10篇 |
神经病学 | 34篇 |
特种医学 | 46篇 |
外科学 | 131篇 |
综合类 | 17篇 |
一般理论 | 2篇 |
预防医学 | 99篇 |
眼科学 | 3篇 |
药学 | 50篇 |
中国医学 | 1篇 |
肿瘤学 | 91篇 |
出版年
2022年 | 10篇 |
2021年 | 21篇 |
2020年 | 16篇 |
2019年 | 18篇 |
2018年 | 25篇 |
2017年 | 20篇 |
2016年 | 20篇 |
2015年 | 27篇 |
2014年 | 34篇 |
2013年 | 44篇 |
2012年 | 54篇 |
2011年 | 60篇 |
2010年 | 43篇 |
2009年 | 23篇 |
2008年 | 41篇 |
2007年 | 30篇 |
2006年 | 41篇 |
2005年 | 39篇 |
2004年 | 32篇 |
2003年 | 28篇 |
2002年 | 39篇 |
2001年 | 24篇 |
2000年 | 42篇 |
1999年 | 25篇 |
1998年 | 7篇 |
1997年 | 17篇 |
1996年 | 8篇 |
1995年 | 13篇 |
1993年 | 11篇 |
1992年 | 18篇 |
1991年 | 20篇 |
1990年 | 18篇 |
1989年 | 12篇 |
1988年 | 22篇 |
1987年 | 15篇 |
1986年 | 18篇 |
1985年 | 13篇 |
1984年 | 15篇 |
1983年 | 11篇 |
1982年 | 11篇 |
1981年 | 6篇 |
1979年 | 9篇 |
1978年 | 7篇 |
1977年 | 7篇 |
1975年 | 4篇 |
1973年 | 5篇 |
1972年 | 5篇 |
1967年 | 5篇 |
1966年 | 8篇 |
1916年 | 4篇 |
排序方式: 共有1088条查询结果,搜索用时 15 毫秒
1.
Hitoshi Ogino Nongchana Klangsuk Wu Jin Christopher T. Bowles Magdi H. Yacoub 《Artificial organs》1995,19(6):525-534
Abstract: The dependence of transient pressure characteristics of a ventricular assist device (VAD) on the compliance of its housing and cannulas was investigated in a mock circulation. The peak rate of change of pressure ( dP/dt max ) values was greater in the cannulas than other compartments and was associated with valve closure-induced pressure oscillations. When cannula compliance was increased from 0.0057 to 0.0129 cm3 /mm Hg, these values decreased by ˜20%, and outflow cannula pressure oscillation frequency decreased from 17.5 Hz by 35%. This trend was also apparent in the inflow. A VAD housing compliance increase from 0.0162 to 0.0483 cm3 /mm Hg caused a dP/dt max decrease of 30% in both the blood chamber and the outflow cannula. The effect of this change on the inflow was weaker implying that housing absorbs the energy associated with outflow deceleration more effectively than the inflow. These findings suggest that increasing VAD housing and cannulas compliance can improve hydrodynamic performance. 相似文献
2.
3.
The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed. 相似文献
4.
5.
Analysis of the coxsackievirus B-adenovirus receptor gene in patients with myocarditis or dilated cardiomyopathy 总被引:1,自引:0,他引:1
Bowles NE Javier Fuentes-Garcia F Makar KA Li H Gibson J Soto F Schwimmbeck PL Schultheiss HP Pauschinger M 《Molecular genetics and metabolism》2002,77(3):257-259
Myocarditis and dilated cardiomyopathy (DCM) are common causes of morbidity and mortality in children and adults, most commonly due to infection with coxsackievirus B or adenovirus. Increased expression of the common human coxsackievirus B-adenovirus receptor (CAR) has been reported in patients with DCM. We investigated the CAR gene in patients with acquired or familial myocarditis/DCM for mutations/polymorphisms. Several polymorphisms or intronic substitutions, distant from the intron-exon boundaries, were identified but no mutations. Based upon these data it appears that CAR gene mutations are not a major host determinant in the development of myocarditis and DCM. 相似文献
6.
7.
8.
Nelson L. Rhodus Bin Cheng Sandra Myers Walter Bowles Vu Ho Frank Ondrey 《Clinical immunology (Orlando, Fla.)》2005,114(3):278
To explore the feasibility of detection of the level of NF-κB-dependent cytokines in oral fluids from patient with oral lichen planus (OLP) for clinical application, 13 OLP subjects were enrolled in the study as were 13 age–sex-matched controls. In each subject, the whole unstimulated saliva (WUS), mixture of saliva and isotonic saline oral rinse (Saliva-NaCl), and lesion tissue transudates (TT) were collected by standard techniques. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids was determined by ELISA. In the three types of oral fluids, a significantly higher level of these cytokines was detected in OLP patients than in normal controls. These results indicate that NF-κB-dependent inflammatory cytokines may be detected at increased levels in certain oral fluids which may have diagnostic and prognostic potential for monitoring disease activity and making therapeutic decisions in patients with OLP. 相似文献
9.
10.
PURPOSE: The aim of this study was to examine the efficacy of the antirefluxing, mucosal-flap valve (AMFV) for biliary drainage relative to technical feasibility, surgical complications, and incidence of ascending cholangitis (AC). METHODS: Twenty-seven infants requiring biliary tract reconstruction underwent valve construction. Twenty biliary atresia (BA) patients received the Kasai procedure, and 7 choledochal cyst (CC) infants had cystectomy and hepatoenterostomy. A retrospective review of all patients was performed including radiographic evaluation of the current valve function in 10 patients. RESULTS: Construction was successful in all cases, and no morbidity was incurred by incorporation of the valve. Of 7 CC patients, there have been no known episodes of AC with mean follow-up of 4.4+/-4.2 years. Of 20 BA patients, there have been 5 deaths (25%), 7 liver transplants (35%), 2 (10%) lost to follow-up, and 6 (30%) survivors. Nine BA patients (45%) have had AC, with patients in all 4 outcome categories represented. Ten patients (5 CC and 5 BA) have been evaluated with barium small bowel radiographs, with no reflux to the liver hilum in all cases. CONCLUSIONS: The AMFV has caused no morbidity and continues to prevent reflux to the liver hilum. Despite functioning as designed, it does not appear to influence the occurrence of AC. Because CC patients had no AC, we feel that infection is related to the underlying atresia rather than to reflux. 相似文献