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51.
OBJECTIVE: Community-based lifestyle intervention may offer the best means of reducing the global epidemic of childhood obesity and its consequences, yet few successful interventions have been reported. The objective was to determine whether increasing extra-curricular levels of activity could reduce weight gain in children. METHODS: A controlled intervention study was conducted using standardised methods to assess outcomes. Two comparable relatively rural communities in Otago, New Zealand formed intervention and control settings. Height, weight, waist circumference and participation in physical activity (by accelerometry) were measured at baseline and at 1 year in 384 children aged 5 to 12 years representing the majority of children in this age group in intervention and control communities. Community Activity Co-ordinators were employed at each school in the intervention area. Their brief was to widen exposure to activity and engage children not interested in traditional sporting activities by encouraging lifestyle-based activities (e.g. walking) and non-traditional sports (e.g. golf and taekwondo) during extra-curricular time at school, after school and during vacations. Simple dietary advice was offered and the wider community was encouraged to participate. RESULTS: Average accelerometry counts at 1 year were 28% (95% CI: 11 to 47%) higher in intervention compared with control children after adjusting for age, sex, baseline values and school. Intervention children spent less time in sedentary activity (ratio 0.91, p = 0.007) and more time in moderate (1.07, p = 0.001) and moderate/vigorous (1.10, p = 0.01) activity. Adjusted mean BMI Z-score was lower in intervention relative to control children by -0.12 units (95% CI: -0.22 to -0.02). CONCLUSION:. An intervention designed to maximise opportunities for physical activity during extra-curricular time at school and during leisure time through the provision of community-based Activity Co-ordinators significantly increased participation in physical activity and slowed unhealthy weight gain in primary school-aged children.  相似文献   
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This paper reviews the literature on the association between exercise and sleep. The epidemiological and experimental evidence for whether or not acute and chronic exercise promote sleep is discussed, as well as moderating factors and agendas for future directions of study. The expectation that exercise will benefit sleep can partly be attributed to traditional hypotheses that sleep serves energy conservation, body restoration or thermoregulatory functions, all of which have guided much of the research in this field. Exercise is a complex activity that can be beneficial to general well-being but may also stress the body. Differences in the exercise protocols studied (e.g. aerobic or anaerobic, intensity, duration) and interactions between individual characteristics (e.g. fitness, age and gender) cloud the current experimental evidence supporting a sleep-enhancing effect of exercise. In addition, the tendency to study changes in small groups of good sleepers may also underestimate the efficacy of exercise for promoting sleep. Athough only moderate effect sizes have been noted, meta-analytical techniques have shown that exercise increased total sleep time and delayed REM sleep onset (10 min), increased slow-wave sleep (SWS) and reduced REM sleep (2-5 min). The sleep-promoting efficacy of exercise in normal and clinical populations has yet to be established empirically.  相似文献   
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Dextroamphetamine administration in healthy controls produces a range of subjective and physiological effects, which have been likened to those occurring during mania. However, it is uncertain if these can be attenuated by lithium since conflicting results have been reported. To date there have been no previous studies examining the effects of valproate on dextroamphetamine-induced mood and physiological changes. The current study was a double-blind, placebo-controlled, study in which volunteers received either 1000 mg sodium valproate (n = 12), 900 mg lithium (n = 9), or placebo (n = 12) pre-treatment for 14 days. Subjective and physiological measures were then obtained prior to administration of a 25 mg dose of dextroamphetamine, and at two time points after administration. Differences in the response to dextroamphetamine were assessed between the three treatment groups. The results of this study show that pre-treatment with lithium only significantly attenuated dextroamphetamine-induced change in happiness, while valproate pre-treatment significantly attenuated the effects of dextroamphetamine on happiness, energy, alertness and on the diastolic blood pressure. These results suggest that lithium and valproate do not have the same mechanism of action on dextroamphetamine-induced changes, and this finding may relate to differences in their mechanism of action in mood disorders.  相似文献   
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There is a growing recognition in the fields of public health and medicine that social determinants of health (SDOH) play a key role in driving health inequities and disparities among various groups, such that a focus upon individual-level medical interventions will have limited effects without the consideration of the macro-level factors that dictate how effectively individuals can manage their health. While the health impacts of mass incarceration have been explored, less attention has been paid to how the “war on drugs” in the United States exacerbates many of the factors that negatively impact health and wellbeing, disproportionately impacting low-income communities and people of colour who already experience structural challenges including discrimination, disinvestment, and racism. The U.S. war on drugs has subjected millions to criminalisation, incarceration, and lifelong criminal records, disrupting or altogether eliminating their access to adequate resources and supports to live healthy lives. This paper examines the ways that “drug war logic” has become embedded in key SDOH and systems, such as employment, education, housing, public benefits, family regulation (commonly referred to as the child welfare system), the drug treatment system, and the healthcare system. Rather than supporting the health and wellbeing of individuals, families, and communities, the U.S. drug war has exacerbated harm in these systems through practices such as drug testing, mandatory reporting, zero-tolerance policies, and coerced treatment. We argue that, because the drug war has become embedded in these systems, medical practitioners can play a significant role in promoting individual and community health by reducing the impact of criminalisation upon healthcare service provision and by becoming engaged in policy reform efforts.

KEY MESSAGES

  • A drug war logic that prioritises and justifies drug prohibition, criminalisation, and punishment has fuelled the expansion of drug surveillance and control mechanisms in numerous facets of everyday life in the United States negatively impacting key social determinants of health, including housing, education, income, and employment.
  • The U.S. drug war’s frontline enforcers are no longer police alone but now include physicians, nurses, teachers, neighbours, social workers, employers, landlords, and others.
  • Physicians and healthcare providers can play a significant role in promoting individual and community health by reducing the impact of criminalisation upon healthcare service provision and engaging in policy reform.
  相似文献   
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BACKGROUND: The number of overweight children has been rapidly increasing, although its prevalence varies by age, sex, ethnicity, and socioeconomic (SES) status. METHODS: Height and weight assessments were used to calculate body mass index (BMI) and BMI percentile on more than 17,000 children in 1 north Florida school district's elementary and middle schools. Based on the child's BMI percentile, each child was placed into 1 of 4 groups: underweight, normal, at risk for overweight, and overweight. Logistic regression was used to test the relative contribution of sex, ethnicity, school (elementary vs middle), age, and SES (indicated by free/reduced vs full-pay lunch status) to a child's weight classification. RESULTS: Overall, 36.2% of the children were either overweight (18.9%) or at risk for overweight (17.4%). Approximately 30% of the kindergarten children were overweight (14.0%) or at risk for overweight (15.5%). African American children were most likely to begin kindergarten overweight. The prevalence of overweight increased for all ethnic groups during the elementary school years. However, African American girls and Hispanic boys were more likely to be overweight than any other ethnic group; Asian girls were least likely to be overweight. These findings could not be readily explained by the effects of SES. Higher SES appeared to be protective but only for white and Hispanic children. CONCLUSIONS: These results confirm the increasing prevalence of overweight in US school children, especially among African American girls and Hispanic boys.  相似文献   
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