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51.
Evidence on the association between insomnia symptoms and mortality is limited and inconsistent. This study examined the association between insomnia symptoms and mortality in cohorts from three countries to show common and unique patterns. The Finnish cohort comprised 6605 employees of the City of Helsinki, aged 40–60 years at baseline in 2000–2002. The Norwegian cohort included 6236 participants from Western Norway, aged 40–45 years at baseline in 1997–1999. The Lithuanian cohort comprised 1602 participants from the City of Palanga, aged 35–74 years at baseline in 2003. Mortality data were derived from the Statistics Finland and Norwegian Cause of Death Registry until the end of 2012, and from the Lithuanian Regional Mortality Register until the end of 2013. Insomnia symptoms comprised difficulties initiating sleep, nocturnal awakenings, and waking up too early. Covariates were age, marital status, education, smoking, alcohol, physical inactivity, obesity, diabetes, cardiovascular diseases, depression, shift work, sleep duration, and self‐rated health. Cox regression analysis was used. Frequent difficulties initiating sleep were associated with all‐cause mortality among men after full adjustments in the Finnish (hazard ratio 2.51; 95% confidence interval 1.07–5.88) and Norwegian (hazard ratio 3.42; 95% confidence interval 1.03–11.35) cohorts. Among women and in Lithuania, insomnia symptoms were not statistically significantly associated with all‐cause mortality after adjustments. In conclusion, difficulties initiating sleep were associated with mortality among Norwegian and Finnish men. Variation and heterogeneity in the association between insomnia symptoms and mortality highlights that further research needs to distinguish between men and women, specific symptoms and national contexts, and focus on more chronic insomnia.  相似文献   
52.
Apoptosis is an important mechanism in organogenesis, but its role in heart development has been poorly characterized. We have here studied apoptosis in the developing ventricular wall of mouse embryonic heart. Developing mice hearts on days 11 to 16 of gestation were studied using in situ end-labeling of degraded DNA (TUNEL), immunocytochemistry of regulatory genes Bcl-2 and Bax, and light and electron microscopy. TUNEL end-labeled apoptotic cells were found in the ventricular wall on days 11 to 16 of gestation. The proportions of apoptotic cells of all cells in the ventricular wall differed between the trabecular and compact regions (P = 0.003) and between the days of gestation (P = 0.0001), the calculated apoptotic index was greater in the compact region at all ages except day 14. Ultrastructural analysis showed typical apoptotic shrinkage, chromatin degradation, and apoptotic bodies in several myoblastic and myocardial endothelial cells which were also positive by DNA end-labeling. Immunocytochemical reaction for the apoptosis checkpoint proteins in the ventricular wall showed clearly more Bcl-2 positive cells than Bax positive cells. The numerical densities of all cells in the compact and trabecular regions remained always higher in the compact region (P = 0.04) despite the fact that apoptosis was present in both areas at the same time. In conclusion, apoptosis takes place in the developing myocardial muscle as well as the myocardial endothelium during ventricular morphogenesis on days 11 through 16 and decreases clearly on day 16. We suggest that apoptosis and its regulatory factors are closely involved in the morphogenesis of the ventricular wall of the mammalian heart.  相似文献   
53.
This paper sheds light on the debate about whether class inequalities have given way to new divisions by employment status, by comparing changes in health inequalities among British and Finnish men and women between 1986 and 1994. Britain experienced high unemployment in the 1980s whereas Finland experienced a sudden increase of unemployment in the early 1990s. We examine how these contrasting labour market situations have influenced changes in health inequalities by employment status and social class using comparable population surveys. In Finland health inequalities by employment status narrowed among men, whereas in Britain they widened or remained stable, with a less strong pattern of change for women. We found similar or slightly larger health inequalities by class among all adults than among the currently employed, with larger class inequalities in Finland than in Britain. We conclude that in countries with high levels of unemployment, there are smaller class inequalities in health among the employed labour force because of the greater chance of a 'healthy worker effect'.  相似文献   
54.
Apoptosis is an important mechanism in organogenesis, but its role in heart development has been poorly characterized. We have here studied apoptosis in the developing ventricular wall of mouse embryonic heart. Developing mice hearts on days 11 to 16 of gestation were studied using in situ end‐labeling of degraded DNA (TUNEL), immunocytochemistry of regulatory genes Bcl‐2 and Bax, and light and electron microscopy. TUNEL end‐labeled apoptotic cells were found in the ventricular wall on days 11 to 16 of gestation. The proportions of apoptotic cells of all cells in the ventricular wall differed between the trabecular and compact regions (P = 0.003) and between the days of gestation (P = 0.0001), the calculated apoptotic index was greater in the compact region at all ages except day 14. Ultrastructural analysis showed typical apoptotic shrinkage, chromatin degradation, and apoptotic bodies in several myoblastic and myocardial endothelial cells which were also positive by DNA end‐labeling. Immunocytochemical reaction for the apoptosis checkpoint proteins in the ventricular wall showed clearly more Bcl‐2 positive cells than Bax positive cells. The numerical densities of all cells in the compact and trabecular regions remained always higher in the compact region (P = 0.04) despite the fact that apoptosis was present in both areas at the same time. In conclusion, apoptosis takes place in the developing myocardial muscle as well as the myocardial endothelium during ventricular morphogenesis on days 11 through 16 and decreases clearly on day 16. We suggest that apoptosis and its regulatory factors are closely involved in the morphogenesis of the ventricular wall of the mammalian heart. Anat Rec 256:208–217, 1999. © 1999 Wiley‐Liss, Inc.  相似文献   
55.
56.
The economic resources available to an individual or a household have been hypothesised to affect health through the direct material effects of living conditions as well as through social comparison and experiences of deprivation. The focus so far has been mainly on current individual or household income, and there is a lack of studies on wealth, a potentially relevant part of household resources. We studied the associations of household wealth and household income with self-rated health, and addressed some theoretical issues related to economic advantage and health. The data were from questionnaire survey of Finnish men and women aged from 45 to 67 years, who were employed by the City of Helsinki from five to seven years before the collection of the data in 2007. We found household wealth to have a strong and consistent association with self-rated health, poor health decreasing with increasing wealth. The relationship was only partly attributable to the association of wealth with employment status, household income, work conditions and health-related behaviour. In contrast, the association of household income with self-rated health was greatly attenuated by taking into account employment status and wealth, and even further attenuated by work conditions. The results suggested a significant contribution of wealth differentials to differences in health status. The insufficiency of current income as the only measure of material welfare was demonstrated. Conditions associated with long-term accumulation of material welfare may be a significant aspect of the causal processes that lead to socioeconomic inequalities in ill health.  相似文献   
57.
58.
We study the modeling and simulation of steady-state measurements of light scattered by a turbid medium taken at the boundary. In particular, we implement the recently introduced corrected diffusion approximation in two spatial dimensions to model these boundary measurements. This implementation uses expansions in plane wave solutions to compute boundary conditions and the additive boundary layer correction, and a finite element method to solve the diffusion equation. We show that this corrected diffusion approximation models boundary measurements substantially better than the standard diffusion approximation in comparison to numerical solutions of the radiative transport equation.  相似文献   
59.
The strength as well as the acoustic properties of trabecular bone are determined by its structure and composition. Consequently, tissue structure and compositional properties also affect the ultrasound propagation in bone. The diagnostic potential of ultrasound has not been fully exploited in clinical quantitative ultrasound devices. The aim of this study was to investigate the ability of quantitative ultrasound pulse-echo imaging, conducted over a broad range of frequencies (1 to 5 MHz), to predict the mechanics, composition and microstructure of trabecular bone. Ultrasound reflection and backscatter parameters correlated significantly with the ultimate strength of the trabecular bone and the bone volume fraction (r = 0.76–0.90, n = 20, p < 0.01). Ultrasound backscatter associated significantly (independently of bone structure or mineral content) with the collagen content of the bone matrix (r = 0.75, radjusted = 0.66, p < 0.01). Interestingly, the applied ultrasound frequency seemed to relate the sensitivity of ultrasound backscatter to different properties of trabecular bone. At frequencies ranging from 1 to 3.5 MHz, the ultrasound backscatter associated significantly with the tissue mechanical and structural parameters. At 5 MHz, the composition of the bone matrix was a more significant determinant of the measured backscatter. This study provides useful information for optimizing the use of pulse-echo measurements, and thereby further emphasizes the diagnostic potential of the ultrasound backscatter measurements of trabecular bone.  相似文献   
60.
Management of hilar bile duct carcinoma.   总被引:9,自引:0,他引:9  
BACKGROUND/AIMS: Hilar cholangiocarcinoma is a rare tumor with a dismal prognosis. Because proximal bile duct cancers are uncommon, outcomes related to various therapeutic interventions are not well defined. METHODOLOGY: Between 1985 and 1997, 55 patients with bile duct cancers involving the proximal third of the extrahepatic bile ducts were seen. The management of patients with resectable and unresectable disease was retrospectively reviewed. All but four patients were followed until the time of death. RESULTS: Forty patients underwent laparotomy following preoperative assessment of extent of disease and 19 patients (35%) ultimately underwent resection with curative intent. Survival was significantly longer in patients who underwent resection (2-year survival 47% vs. 18%; P = 0.027). Of those patients whose disease was resected, 11 patients received adjuvant radiotherapy. Survival for this group was not significantly different from that seen in patients who did not receive adjuvant radiotherapy. Similarly, in patients with unresectable disease, administration of radiotherapy was not associated with an improved outcome. CONCLUSIONS: Locoregional extent of disease is the greatest problem in cases of proximal bile duct cancers. Resection provides the best hope for long-term survival, but new adjuvant strategies are needed.  相似文献   
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