全文获取类型
收费全文 | 1440篇 |
免费 | 13篇 |
国内免费 | 2篇 |
专业分类
综合类 | 1篇 |
化学工业 | 19篇 |
金属工艺 | 3篇 |
机械仪表 | 7篇 |
建筑科学 | 4篇 |
矿业工程 | 1篇 |
能源动力 | 11篇 |
轻工业 | 15篇 |
水利工程 | 2篇 |
石油天然气 | 6篇 |
无线电 | 20篇 |
一般工业技术 | 30篇 |
冶金工业 | 1322篇 |
自动化技术 | 14篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 6篇 |
2019年 | 7篇 |
2018年 | 4篇 |
2017年 | 7篇 |
2016年 | 8篇 |
2015年 | 3篇 |
2014年 | 7篇 |
2013年 | 9篇 |
2012年 | 8篇 |
2011年 | 7篇 |
2010年 | 8篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2000年 | 1篇 |
1999年 | 39篇 |
1998年 | 396篇 |
1997年 | 243篇 |
1996年 | 148篇 |
1995年 | 81篇 |
1994年 | 65篇 |
1993年 | 79篇 |
1992年 | 8篇 |
1991年 | 14篇 |
1990年 | 8篇 |
1989年 | 13篇 |
1988年 | 19篇 |
1987年 | 15篇 |
1986年 | 13篇 |
1985年 | 11篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 16篇 |
1980年 | 17篇 |
1978年 | 4篇 |
1977年 | 47篇 |
1976年 | 79篇 |
1975年 | 4篇 |
1955年 | 3篇 |
排序方式: 共有1455条查询结果,搜索用时 890 毫秒
81.
Although the arterial tree is exposed to increased pressure in hypertensive patients, paradoxically, the complications of hypertension (heart attacks, stroke) are mainly thrombotic rather than hemorrhagic. Patients with left ventricular (LV) hypertrophy are at high risk of the complications of hypertension. We performed a cross-sectional study of 178 patients attending a hypertension clinic in a city center teaching hospital, and measured plasma levels of the soluble adhesion molecule P-selectin (associated with platelet activity/function and atherosclerosis), the von Willebrand factor (vWf; a marker of endothelial dysfunction), fibrin D-dimer (an index of thrombogenesis), plasminogen activator inhibitor (PAI, an index of fibrinolysis), lipoprotein(a) (Lp(a), associated with thrombogenesis and atherogenesis) and hemorheological indexes (fibrinogen, hematocrit, plasma viscosity, hemoglobin) in patients with essential hypertension, in whom the LV mass and LV mass index were determined using echocardiography. The 178 patients (86 men, mean age 54 +/- 15 years) were compared with 47 normotensive healthy controls (aged 56 +/- 20 years). Hypertensive patients had higher P-selectin, PAI, vWf, fibrin D-dimer, Lp(a), plasma fibrinogen, and plasma viscosity when compared with controls. Black hypertensive patients had higher Lp(a) levels and LV septal and posterior wall thickness on echocardiography, but lower plasma PAI levels. Patients with LV hypertrophy (defined as a LV mass index > 134 g/m2 in men or > 110 g/m2 in women) had higher plasma fibrinogen compared with those without LV hypertrophy. Systolic blood pressures were significantly correlated to age, plasma viscosity, plasma fibrinogen, and vWf. Diastolic blood pressures were significantly correlated with age and plasma fibrinogen. Fibrinogen levels were correlated with LV mass, LV mass index, left atrial size, plasma viscosity, and vWf. Fibrin D-dimer levels were significantly correlated with vWf and fibrinogen levels. Thus, hypertensive patients have high plasma fibrinogen levels, thrombogenesis, and impaired fibrinolysis (as indicated by high D-dimer and PAI levels, respectively), platelet activation (raised soluble P-selectin), and endothelial dysfunction (high vWF). The high plasma fibrinogen levels were related to blood pressures, LV mass index (and LV hypertrophy), and left atrial size. These abnormalities in hemorheologic factors and markers of thrombogenesis and endothelial function may act synergistically to increase the risk of thrombogenesis and atherosclerosis in hypertensive patients. 相似文献
82.
83.
84.
This paper discusses the issues of providing an empirically validated, manual-based-treatment when viewed from the perspective of a practicing clinical psychologist. The trend for empirically proven treatment is reviewed briefly, and initial data are provided illustrating a manual-based-treatment for post-traumatic stress disorder (PTSD) following a motor vehicle accident. The relatively brief (9-12 session) psychological treatment was effective in reducing PTSD symptoms as measured on the Clinician Administered PTSD Scale, for all 10 subjects. The results are discussed form the practicing clinician's perspective: generalization to a clinical population, ethical concerns of limited treatment goals, individually tailored vs standardized treatments in clinical practice, concerns for co-morbid conditions, and how this type of study might impact on practice in an era of managed health care. Issues of incorporating manual based treatments into clinical practice are discussed, with consideration of gains, the limits and the constraints this would bring to the practice of psychology. 相似文献
85.
86.
87.
Haemagglutination of purified F42 fimbriae was found to be inhibited by N-acetyl-galactosamine. Purified F42 fimbrial adhesin reacted with distinct membrane components from chicken erythrocytes (35, 37 and 40 kDa) in immunoblot analysis, suggesting that the binding occurred to proteins or glycoproteins. 相似文献
88.
89.
D Reddy AS Pollock SA Clark K Sooy RC Vasavada AF Stewart T Honeyman S Christakos 《Canadian Metallurgical Quarterly》1997,94(5):1961-1966
90.