全文获取类型
收费全文 | 493篇 |
免费 | 25篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 12篇 |
妇产科学 | 2篇 |
基础医学 | 29篇 |
临床医学 | 29篇 |
内科学 | 258篇 |
神经病学 | 19篇 |
特种医学 | 59篇 |
外科学 | 11篇 |
综合类 | 38篇 |
预防医学 | 61篇 |
眼科学 | 2篇 |
药学 | 14篇 |
肿瘤学 | 9篇 |
出版年
2018年 | 5篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 4篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 9篇 |
2008年 | 14篇 |
2007年 | 18篇 |
2006年 | 10篇 |
2005年 | 13篇 |
2004年 | 11篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 14篇 |
2000年 | 17篇 |
1999年 | 8篇 |
1998年 | 12篇 |
1997年 | 11篇 |
1996年 | 7篇 |
1995年 | 10篇 |
1994年 | 15篇 |
1993年 | 7篇 |
1992年 | 15篇 |
1991年 | 16篇 |
1990年 | 27篇 |
1989年 | 24篇 |
1988年 | 24篇 |
1987年 | 24篇 |
1986年 | 16篇 |
1985年 | 13篇 |
1984年 | 14篇 |
1983年 | 13篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 4篇 |
1979年 | 18篇 |
1978年 | 8篇 |
1977年 | 15篇 |
1976年 | 12篇 |
1975年 | 8篇 |
1974年 | 11篇 |
1973年 | 5篇 |
1972年 | 7篇 |
1971年 | 7篇 |
1970年 | 6篇 |
1969年 | 2篇 |
1967年 | 5篇 |
1966年 | 3篇 |
1965年 | 2篇 |
排序方式: 共有544条查询结果,搜索用时 15 毫秒
151.
D Levy K M Anderson D D Savage S A Balkus W B Kannel W P Castelli 《The American journal of cardiology》1987,60(7):560-565
The association of ventricular arrhythmias with left ventricular (LV) hypertrophy was examined in 6,218 participants in the Framingham Heart Study. Electrocardiographic (ECG) LV hypertrophy was present in 171 subjects and echocardiographic hypertrophy was detected in 869. Echocardiographic LV hypertrophy was associated with increased risk for each of 6 ventricular arrhythmia grades in men (relative risk up to 8.9, p less than 0.01), and 4 of 6 grades in women (p less than 0.05). Similarly, men with ECG LV hypertrophy were at increased risk for 4 of 6 arrhythmia grades (p less than 0.05). However, owing to low prevalence ECG LV hypertrophy was not associated with arrhythmia in women. After adjustment for age, sex, systolic blood pressure, valvular heart disease, angina pectoris and acute myocardial infarction, the association of echocardiographic but not ECG LV hypertrophy with ventricular arrhythmia remained significant (p less than 0.001). Thus, echocardiographic LV hypertrophy is more prevalent and more sensitive for ventricular arrhythmias than ECG LV hypertrophy. 相似文献
152.
P E Leaverton P D Sorlie J C Kleinman A L Dannenberg L Ingster-Moore W B Kannel J C Cornoni-Huntley 《Journal of chronic diseases》1987,40(8):775-784
The Framingham Heart Study has been the foundation upon which several national policies regarding risk factors for coronary heart disease mortality are based. The NHANES I Epidemiologic Followup Study is the first national cohort study based upon a comprehensive medical examination of a probability sample of United States adults. The average follow-up time was 10 years. This study afforded an opportunity to evaluate the generalizability of the Framingham risk model, using systolic blood pressure, total cholesterol, and cigarette smoking, to the U.S. population with respect to predicting death from coronary heart disease. The Framingham model predicts remarkably well for this national sample. The major risk factors for coronary heart disease mortality described in previous Framingham analyses are applicable to the United States white adult population. 相似文献
153.
Cross-sectional and prospective associations between lung function and potential determinants were examined in the Framingham Study. Personal characteristics of interest were body height and weight, hand grip strength, smoking habits, history of respiratory symptoms and disease, and hematocrit. Baseline pulmonary function was the most powerful indicator of future FEV1, and cigarette smoking was the most important correctable influence. In addition to baseline FEV1, FVC and smoking habits, the important predictors of future lung function were age, relative weight, respiratory symptoms and hematocrit. There was a higher follow-up FEV1 in those who quit smoking compared to those who continued even after adjustment for other associated variables. Relative weight and hematocrit were associated with FEV1 measured 14 years after baseline (directly for relative weight and inversely for hematocrit). 相似文献
155.
156.
本文建立了以紫外230nm波长检测的反相高效液相色谱法(RP-HPLC)测定家兔血浆中甲苯喹派浓度。填料使用LiChrosorb RP-C18,流动相为甲醇—水—三乙胺—磷酸(63:37:1:0.8 v/v),血样(或尿样)经碱化后用乙醚提取,再以0.2 mol/L硫酸回提,进样。方法回收率为99.84±3.10(SD)%;天内、天间精密度平均CV为4.12%及3.95%(n=5);最低检测限3ng.经提取的标准线性浓度在25~2000 ng/ml范围内,Y=0.002865X-0.01346,r=0.9999,内源性物质及可能的合并用药不干扰色谱测定。文内用质谱法鉴定血样中甲苯喹哌色谱峰纯度,并由尿样分析对其主要代谢物予以初步验证。本法可应用于药代动力学参数测定。家兔按8mg/kg静注后,药—时曲线符合二室模型T1/2=4.8008±1.1522(SD)h。 相似文献
157.
Five patients with chronic traumatic diaphragmatic hernia presented with symptoms of acute intestinal obstruction and unilateral pleural effusion. In each case, infarcted herniated abdominal structures were found at surgery. The presence of an ipsilateral pleural effusion is an important radiographic sign, which may indicate strangulation in patients with chronic traumatic diaphragmatic hernia. 相似文献
158.
The hypothesis that obesity-related hypertension is relatively innocuous was explored by an examination of cardiovascular events over 34 years of follow-up when related to biennially measured weights and blood pressures using time-dependent covariate proportional hazards analysis. The 5209 participants were also classified by age, cigarette smoking, and antihypertensive treatment at each of four baseline examinations with 8-year follow-up periods. Over the period of follow-up, there were 978 cardiovascular events in men and 836 in women. Risk of cardiovascular morbidity and mortality in general and of CHD in particular was as strongly related to hypertension at all levels of body mass index. This was also found to apply when adjustment was made for possible confounding by cigarette smoking. Age and smoking-adjusted absolute risks of cardiovascular events were found to be higher in hypertensive individuals with high than with low BMIs. Furthermore, the relative risk of cardiovascular disease did not vary significantly with BMI. Thus hypertension is at least as dangerous in obese as in lean persons at all ages in either sex, providing no support for the hypothesis that hypertension in the obese is more benign. This is important, since obesity predisposes to hypertension and most who have hypertension are obese. This report examines the hypothesis for CVD outcomes considered by previous reports and also the subcategories of CVD disease such as myocardial infarction and stroke, and includes data on both men and women and on young and old. 相似文献
159.
160.