首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   309篇
  免费   14篇
  国内免费   1篇
妇产科学   1篇
基础医学   51篇
口腔科学   4篇
临床医学   41篇
内科学   99篇
皮肤病学   6篇
神经病学   33篇
特种医学   6篇
外科学   25篇
预防医学   47篇
眼科学   2篇
药学   6篇
肿瘤学   3篇
  2023年   2篇
  2021年   7篇
  2020年   3篇
  2019年   3篇
  2018年   7篇
  2017年   5篇
  2016年   5篇
  2015年   6篇
  2014年   4篇
  2013年   15篇
  2012年   18篇
  2011年   25篇
  2010年   6篇
  2009年   7篇
  2008年   11篇
  2007年   19篇
  2006年   19篇
  2005年   20篇
  2004年   18篇
  2003年   12篇
  2002年   18篇
  2001年   4篇
  2000年   6篇
  1999年   5篇
  1998年   7篇
  1997年   6篇
  1996年   4篇
  1995年   3篇
  1994年   4篇
  1992年   3篇
  1991年   3篇
  1988年   2篇
  1986年   3篇
  1985年   2篇
  1984年   4篇
  1983年   2篇
  1982年   3篇
  1981年   5篇
  1980年   2篇
  1978年   3篇
  1977年   2篇
  1976年   3篇
  1975年   3篇
  1967年   1篇
  1966年   4篇
  1965年   1篇
  1960年   1篇
  1958年   1篇
  1954年   1篇
  1931年   1篇
排序方式: 共有324条查询结果,搜索用时 281 毫秒
1.
BACKGROUND: Airway inflammation is a characteristic feature of bronchial asthma. Previous studies have shown an increased local inflammatory activity in the airway mucosa of asthma patients. OBJECTIVES: To analyze the association of asthma with three sensitive markers of systemic inflammation, C-reactive protein, serum amyloid-A (SAA), and plasma fibrinogen. METHODS: A cross-sectional, population-based study including 1,513 Finnish men aged 45 to 74 years, who participated in a chronic disease risk factor survey in 1997. Of the participating men, 97 were classified as asthma patients. The odds ratios of asthma were analyzed by quartile of each inflammation marker. RESULTS: In logistic regression models the age-adjusted odds ratios (second, third, and fourth quartile as compared with the first quartile) of asthma increased gradually with increasing quartile of C-reactive protein (1.28, 1.19, 1.96, P for trend = 0.039), SAA (1.20, 3.00, 3.49, P for trend < 0.001), and fibrinogen (1.22, 1.79, 3.16, P for trend < 0.001). The associations were independent of smoking. Further adjustment for waist-to-hip ratio, a marker of central obesity, and symptoms of chronic bronchitis weakened the observed association, but the increasing trend in the association of SAA and fibrinogen with asthma remained highly significant. CONCLUSIONS: Sensitive markers of systemic inflammation, particularly SAA and fibrinogen, were positively and significantly associated with asthma prevalence. These findings support the hypothesis that not only local, but also systemic, inflammation exist in bronchial asthma.  相似文献   
2.
The purpose of this study was to describe coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA) patients' need for nursing informational support in health-related (HRQoL) items before and after coronary artery procedures. As well we present the adequacy of informational support from patients' viewpoint. The study sample (N=625) consisted of consecutive male (N=439) and female (N=176) patients with CAD who were treated with elective CABG or PTCA. The data were collected by structured interview before coronary artery procedures and by mailed questionnaires 6 and 12 months afterwards in 1999-2001. Patients in both groups reported needing the most information about recovery and psychosocial functioning before and after the treatments. Single HRQoL items identified that the expectations of women and men differed during the follow-up period. Women in the PTCA group needed more informational support than men before procedures, while men needed more support afterwards. Our results suggest that the content of informational support is different for male and female patients before and after the coronary artery procedures. The effects of nursing interventions and instruments for measuring change in patients' outcome resulting from nursing interventions should be developed further.  相似文献   
3.
BACKGROUND AND PURPOSE: Administrative registers, like hospital discharge registers and causes of death registers are used for the monitoring of disease incidences and in the follow-up studies. Obtaining reliable results requires that the diagnoses in these registers are correct and the coverage of the registers is high. The purpose of this study was to evaluate the validity of the Finnish hospital discharge registers and causes of death registers stroke diagnoses against the population-based FINSTROKE register. METHODS: All first stroke events from the hospital discharge registers and causes of death registers from the areas covered by the FINSTROKE register were obtained for years 1993-1998 and linked to the FINSTROKE register. The sensitivity and positive predictive values were calculated. RESULTS: A total of 3633 stroke events, 767 fatal and 2866 non-fatal strokes, were included in the registers. The sensitivity for all first stroke events was 85%, for fatal strokes 86% and for non-fatal strokes 85%. The positive predictive values for all first strokes was 86%, for fatal strokes 92% and for non-fatal strokes 85%. The sensitivity as well as the positive predictive values for subarachnoid haemorrhage and intracerebral haemorrhage was higher than for cerebral infarctions. There were no marked differences in the sensitivity or positive predictive values between men and women. CONCLUSIONS: The sensitivity and the positive predictive values of the Finnish hospital discharge registers and causes of death registers are fairly good. Finnish administrative registers can be used for the monitoring of stroke incidence, but the number of cerebral infarctions should be interpreted with caution.  相似文献   
4.
5.
Ten young (aged 23–30 years) and nine older (aged 54–59 years) healthy men with similar estimated limb muscle volumes performed, in random order, three different types of ergometer exercise tests (one-arm cranking, two-arm cranking, and two-leg cycling) up to the maximal level. Values for work load (WL), peak oxygen consumption , peak heart rate (HR), peak ventilation , respiratory gas exchange ratio (R), recovery blood lactate concentration [La], and rating of perceived exertion (RPE) were compared between the age-groups in the given exercise modes. No significant age-related differences in WL, peak , peak HR, R, [La], or RPE were found in one-arm or two-arm cranking. During one-arm cranking the mean peak was 1.65 (SD 0.26)1 · min–1 among the young men and 1.63 (SD 0.10)1 · min–1 among the older men. Corresponding mean peak during two-arm cranking was 2.19 (SD 0.32)1 · min-1 and 2.09 (SD 0.18)1 · min–1, respectively. During one-arm cranking peak was higher (P < 0.05) among the older men compared to the young men. During two-leg cycling the young men showed higher values in WL (P < 0.001), peak (P < 0.001), and peak HR (P < 0.001). The mean peak was 3.54 (SD 0.24)1 · min–1 among the young men and 3.02 (SD 0.20)1 · min–1 among the older men. Corresponding mean peak HR was 182 (SD 5) beats · min–1 and 170 (SD 8) beats · min–1, respectively. During two-leg cycling, peak , R, [La], and RPE did not differ between the two age-groups. In summary, the older men with similar sizes of estimated arm and leg muscle volumes as the young men had a reduced physical work capacity in two-leg cycling. In one-arm or two-arm cranking, no significant difference in work capacity was found between the age-groups. These results indicate, that in healthy men, age, at least up to the 6th decade of life, is not necessarily associated with a decline in physical work capacity in exercises using relatively small muscle groups, in which the limiting factors are more peripheral than central.  相似文献   
6.
We describe patient E.P. who occasionally perceives a ‘ghost' hand which copies the previous positions of the left hand with a 0.5–1 min time lag, but follows the movement patterns of the right hand. The symptoms started after an operation of a ruptured aneurysm, followed by an infarction of the right frontal lobe; E.P. also has a previously lesioned corpus callosum. Neuromagnetic recordings revealed that activity of the left secondary somatosensory cortex was strongly suppressed during the ghost arm percept, thereby providing an objective correlate for E.P.'s sensations. We conclude that simultaneous mental contents about body scheme may be based on neural information extracted at considerably different times, resulting in fragmentation of bodily awareness.  相似文献   
7.
Summary Six healthy men aged 25 to 37 walked on a treadmill at work levels of 21 and 41% of their for 25 to 30 min wearing gas protective clothing (GPC) consisting of an impermeable suit with a self-contained breathing apparatus (total weight 25 kg) or shorts (control tests, CT) in a temperate environment (t a 24.3°C ± 1.0°C, rh 30–50%). When the GPC was worn at 21 and 41% , the most prominent increases, compared with the CT, were noted in the heart rate ( ± SE, 120 ± 5 vs 76 ± 3 beats min–1 and 171 ± 5 vs 103 ± 3 beats min–1), mean skin temperature (36.1 ± 0.2 vs 31.3° C ± 0.1°C and 36.9 ± 0.3 vs 30.9°C ± 0.4°C) and sweat rate (473 ± 51 vs 70 ± 23 g m–2 h–1 and 766 ± 81 vs 135 ± 18 g m–2 h–1) indicating a high cardiovascular and thermoregulatory strain, which was not decreased by ventilating the suit with an air flow of 281 min–1 at 41% . The ventilation, oxygen consumption and production of carbon dioxide increased in relation to the extra weight of the GPC, partly dependent on the dynamic work level. It was concluded that the increase in the physiological load caused by the GPC was so high that the work-rest regimens, workers' level of physical fitness, cardiovascular health and heat tolerance should be considered whenever gas protective clothing is used.  相似文献   
8.
The role of hemostatic factors as predictors of coronary heart disease (CHD) and total mortality is poorly understood. Therefore, we carried out a prospective cohort study in Finland. In 1992, a random population sample of 2378 men and women aged 45 to 64 years was investigated and then followed up until December 31, 1998. During the follow-up, 133 CHD events were observed; 73 were among participants free of CHD at baseline. The total number of deaths was 124. After adjustment for traditional risk factors and prevalent CHD at baseline and correction for regression dilution bias, a 1-SD increase in plasminogen was associated with a 1.41-fold (95% CI 1.09 to 1.81) increase in CHD risk. The predictive power of plasminogen depended significantly on the level of total cholesterol being stronger for persons with high cholesterol. A 1-SD increase in fibrinogen was associated with a 1.23-fold (95% CI 1.05 to 1.44) increase in all-cause mortality, but its association with CHD events did not reach statistical significance. Factor VII antigen or coagulant activity or lipoprotein(a) were not independent predictors of CHD risk. These findings support the role of plasminogen as a risk factor for CHD events.  相似文献   
9.
10.
The association between diabetes and subclinical atherosclerosis is well established. The effect of non-diabetic glucose intolerance on early atherosclerosis is not as straightforward, and the data regarding sex-related differences in this matter are limited. Therefore, our aim was to investigate these associations in men and women separately. We studied 1,304 Finnish men and women over 45?years of age who participated in the Finnish Health 2000 Survey. Ultrasonically determined carotid artery intima-media thickness and elasticity were used as markers of early atherosclerosis. Glucose tolerance was categorized according to the American Diabetes Association criteria for diabetes mellitus. Age-adjusted means for carotid artery intima-media thickness and elasticity indices were significantly (P?<?0.05) associated with glucose tolerance status in both sexes. There was a trend of increasing early atherosclerosis with the worsening of glucose tolerance in men and women. These associations were weakened in both sexes after further adjustments for other cardiovascular risk factors. In women, but not in men, significant (P?<?0.05) associations between glucose tolerance status and carotid artery elasticity were seen even after these further adjustments. Diabetes and non-diabetic glucose intolerance are associated with increased early carotid atherosclerosis compared with normal glucose tolerance in both sexes. Our results suggest that women with glucose intolerance may be in greater risk than men.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号