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191.
Objective: To examine the relationship between self‐reported body mass index (BMI) and health‐related quality of life in the general adult population in the United States. Research Methods and Procedures: Using data from 109,076 respondents in the 1996 Behavioral Risk Factor Surveillance System, we examined how self‐reported BMI is associated with five health‐related quality of life measures developed by the Centers for Disease Control and Prevention for population health surveillance. Results: After adjusting for age, gender, race or ethnicity, educational attainment, employment status, smoking status, and physical activity status, participants with a self‐reported BMI of <18.5 kg/m2 and participants with a self‐reported BMI of ≥30 kg/m2 reported impaired quality of life. Compared with persons with a self‐reported BMI of 18.5 to <25 kg/m2, odds ratios (ORs) of poor or fair self‐rated health increased among persons with self‐reported BMIs of <18.5 (1.57, 95% confidence interval [CI]: 1.31 to 1.89), 25 to <30 kg/m2 (1.12, 95% CI: 1.04 to 1.20), 30 to <35 kg/m2 (1.65, 95% CI: 1.50 to 1.81), 35 to <40 kg/m2 (2.58, 95% CI: 2.21 to 3.00), and ≥40 kg/m2 (3.23, 95% CI: 2.63 to 3.95); ORs for reporting ≥14 days of poor physical health during the previous 30 days were 1.44 (95% CI: 1.21 to 1.72), 1.04 (95% CI: 0.96 to 1.14), 1.32 (95% CI: 1.19 to 1.47), 1.80 (95% CI: 1.52 to 2.13), and 2.37 (95% CI: 1.90 to 2.94), respectively; ORs for having ≥14 days of poor mental health during the previous 30 days were 1.18 (95% CI: 0.97 to 1.42), 1.02 (95% CI: 0.95 to 1.11), 1.22 (95% CI: 1.10 to 1.36), 1.68 (95% CI: 1.42 to 1.98), and 1.66 (95% CI: 1.32 to 2.09), respectively. Discussion: In the largest study to date, low and increased self‐reported BMI significantly impaired health‐related quality of life. Particularly, deviations from normal BMI affected physical functioning more strongly than mental functioning.  相似文献   
192.
This study aimed to evaluate the applicability of the Australian River Assessment System (AUSRIVAS) bioassessment methodology to assess the biological health of streams in the upper-middle Brantas River catchment, East Java, Indonesia. A total of 84 `minimally disturbed' reference sites were selected and sampled for macroinvertebrates in riffle habitats. Sampling of macroinvertebrates and identification to family level was conducted by local biologists following intensive training, and under supervision. A quality control protocol was introduced to ensure the data were reliable and reproducible. A suite of `potential predictor' and `monitoring' environmental variables were also measured at each site. The macroinvertebrate data were used to develop a predictive AUSRIVAS model for the upper-middle Brantas river, and the model was then used to assess the `health' of 15 test sites in the catchment. Bioassessment outputs – Observed (O)/Expected (E) ratios – were found to be broadly related to measures of physical disturbance from land use and riparian degradation. Through the process of local reference site selection and sampling, model development, validation and subsequent use, the Australian AUSRIVAS rapid bioassessment method was assessed as being highly applicable to the upper-middle catchment sections of Indonesian river systems.  相似文献   
193.
The incidence of food poisoning in England and Wales has been increasing for many years and it is now a major public health problem. Superimposed on this general rising trend is a well-established tendency for the number of cases of food poisoning to rise during the summer when warm weather favours the multiplication of pathogenic micro-organisms. This paper shows that weekly notifications of food poisoning in England and Wales are strongly associated with environmental temperatures, but that there are some important time lags in this relationship. The number of cases of food poisoning in a given week was only weakly correlated with the temperature of that week and the one preceding it. This suggests that factors operating close to the point of consumption within or outside the home are not the principal cause of the rise in food poisoning associated with warm summer conditions. There was a much stronger association with temperatures 2–5 weeks earlier, pointing to the importance of factors operating earlier in the food production or distribution system. The results of this study suggest that the food poisoning problem requires action by food producers and distributors as well as by consumers. Received: 15 May 2000 / Revised: 17 October 2000 / Accepted: 18 October 2000  相似文献   
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195.
The paper provides an overview of approaches to dioxin risk assessment employed by different agencies worldwide over the past 20 years. Our insights regarding understanding of the toxicity of dioxins have advanced tremendously in recent years; however, important data gaps still exist. More information on topics such as mechanism of interaction, effects at low levels of exposure, interspecies differences, and sensitive populations is needed. Some differences exist between USEPA's approach to dioxin assessment and that of other health organizations around the world. The authors conclude that USEPA's reassessment of dioxin and related compounds may place too much confidence in the ability to accurately predict cancer risks at low doses. Further, it is important to derive health-based guidance values for noncancer end points especially in accordance with emerging reports that reproductive and developmental end points are very sensitive to dioxins. A worldwide convergence on the health assessment value being around 1 to 4?pg/kg/day is noted.  相似文献   
196.
Objective: The aim of the study was to assess the uptake of dental services by the old and very old population within the scope of the Berlin Aging Study (Berliner Altersstudie BASE ). Design: A multi‐disciplinary structured interview was performed on 928 subjects, aged from 70 to 103 years of whom 516 persons volunteered to take part in a 14‐session intensive protocol. Six representative study groups were matched for age and gender. Subjects were asked to recall the timing of their most recent dental visit. Data were validated by sending for dental records and compared with all study participants from the multi‐disciplinary intake assessment. Data were related to age group, dental state, dementia and education. Results: Reported last contact with dental services ranged from 2 weeks to 52 years (median 18 months) with a higher time lapse in the study groups aged 85 and older. Dentate subjects had seen their dentist more recently than edentate subjects. Higher education correlated with an increased dental utilisation. Subjective memory on the time lapse since the last dental appointment coincided in 13% of the subjects with available dental records (n=84), was misjudged between one and six months in 55%, and by more than six months in the remainder. Moderately or severely demented subjects who remembered their last dental appointment (n=48 of 70) showed no consistently different utilisation to healthy or mildly demented studs participants. Conclusion: Edentate old and very old subjects show the least frequent utilisation of dental services. Data on motivation and barriers to care are needed to develop strategies to improve the use of dental services and thus promote oral health in late life.  相似文献   
197.
We have studied the primary structures of myosins from chicken muscles in order to clarify the relationship between structure and function of muscle myosin. The primary structures of the various kinds of light chains from chicken muscle myosins have been determined. We also report the primary structure of the 23K fragment of subfragment-1 (S-1) component from the heavy chain of chicken fast skeletal muscle myosin. In addition, antibody was prepared against the 23K fragment. The antibody was found to inhibit the Mg2+-ATPase activity and the initial Pi burst of the ATPase in the S-1 component. The antibody suppressed the ATP-induced fluorescence enhancement of S-1, though it did not suppress the binding of ATP to S-1. These results are also discussed.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985.  相似文献   
198.
199.
The situation is considered where the multivariate distribution of certain variables X1, X2, …, Xp is changing with time in a population because natural selection related to the X's is taking place. It is assumed that random samples taken from the population at times t1, t2, …, ts are available and it is desirable to estimate the fitness function wt(x1, x2,…,xp) which shows how the number of individuals with Xi = xi, i = 1, 2, …, p at time t is related to the number of individuals with the same X values at time zero. Tests for population changes are discussed and indices of the selection on the population dispersion and the population mean are proposed. The situation with a multivariate normal distribution is considered as a special case. A maximum likelihood method that can be applied with any form of population distribution is proposed for estimating wt. The methods discussed in the paper are illustrated with data on four dimensions of male Egyptian skulls covering a time span from about 4500 B.C. to about 300 A.D. In this case there seems to have been very little selection on the population dispersion but considerable selection on means.  相似文献   
200.
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