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101.
Objectives. We examined the relation of household crowding to food insecurity among Inuit families with school-aged children in Arctic Quebec.Methods. We analyzed data collected between October 2005 and February 2010 from 292 primary caregiver–child dyads from 14 Inuit communities. We collected information about household conditions, food security, and family socioeconomic characteristics by interviews. We used logistic regression models to examine the association between household crowding and food insecurity.Results. Nearly 62% of Inuit families in the Canadian Arctic resided in more crowded households, placing them at risk for food insecurity. About 27% of the families reported reducing the size of their children’s meals because of lack of money. The likelihood of reducing the size of children’s meals was greater in crowded households (odds ratio = 3.73; 95% confidence interval = 1.96, 7.12). After we adjusted for different socioeconomic characteristics, results remained statistically significant.Conclusions. Interventions operating across different levels (community, regional, national) are needed to ensure food security in the region. Targeting families living in crowded conditions as part of social and public health policies aiming to reduce food insecurity in the Arctic could be beneficial.Inadequate housing conditions (e.g., crowding and structural damage) are prevalent among First Nations and Inuit communities in Canada and elsewhere.1 In Nunavik, the Inuit homeland in Arctic Quebec, Canada, the government promoted the relocation of many Inuit families to fledgling communities during the 1950s. Relocated families were moved to small, poorly heated and insulated accommodations. Since then, different programs have been designed by the federal, provincial, territorial, and regional governments to address the housing problem in Nunavik and across the Canadian Arctic.2 At present, more than 90% of the Nunavik population has reported living in social (subsidized) housing.3 In this region, social housing units are allocated locally through a point-based system set according to specific criteria, so that applicants most in need are given first priority (e.g., families with lower income, with young children, and living in overcrowded dwellings).2 Rent is set according to household income, while also considering the cost of living.4 Thus, in Nunavik, housing tenure does not differentiate between households on the basis of financial security or income level, given that nearly all of the population resides in social housing. Such organization rather highlights the high degree of financial need throughout this population and a limited private residential market unattainable by most of the population.Household overcrowding, generally defined as more than 1 person per room,5 is particularly problematic in Nunavik. According to Statistics Canada, 49% of the 2006 population lived in overcrowded houses.5 Often, overcrowding is approached as a consequence of economic difficulties. Living in smaller homes or in shared accommodation has been known as a way to lower living costs to dedicate the available financial resources to other basic necessities.6 In such situations, overcrowded households may experience higher food insecurity as a result of a precarious economic situation. In the particular case of Nunavik, however, crowding is a direct consequence of an underlying, and persistent, lack of housing. Household crowding in Nunavik is not only a product of financial difficulties but also an effect of the rapidly growing and young population. Between 2001 and 2006, the population in Nunavik increased by 12% compared with 4% for the province of Quebec. During the past 3 decades, the population has doubled from 5860 in 1986 to 12 090 in 2011.7 In 2008, it was estimated that more than 900 new housing units were needed, but only 239 units were constructed.8 The housing backlog is further compounded by high costs of construction and short building seasons.The housing situation in Nunavik and throughout the Canadian Arctic raises concerns, in terms of both public health and the health of each individual resident, especially that of children.9–14 Indeed, studies have shown that household crowding is associated with poorer respiratory health, especially among children.12,15 In crowded dwellings, the lack of privacy and the difficulty of withdrawing from (unwanted) social interactions may limit the ability of controlling one’s home situation and lead to “overarousal.”16 Household crowding also has been identified as eliciting chronic stress responses in adults,17 anger and depression18 with possible repercussions on behaviors,19–22 withdrawal,23 and reduced social support24 that, we contend, could influence household food insecurity.Food insecurity occurs when it is not possible to obtain safe, sufficient, and nutritiously adequate foods for a healthy life in socially and culturally acceptable ways.25–27 Studies have shown that in a situation of food insecurity, adults generally first reduce their own food consumption. As the situation becomes more severe, children’s diets also will be reduced, particularly in low-income households with single mothers.28,29 In 2012, 14% of the households in Canada experienced food insecurity.30 In Canadian Arctic communities, food insecurity is high: 62.2% and 31.6% of children live in food-insecure households in Nunavut and Northwest Territories, respectively.30 In Nunavik, the proportion of Inuit children experiencing food insecurity reached 30% in 2006.31 Studies emphasize that a reduction of the quality in diet and nutrient intake resulting from food insecurity is linked to various health issues in children, including poor health,25,32–34 developmental delays,35 and poor mental health.36Access to food products supplied from southern regions of Quebec comes at a very high cost to Nunavik, with an average price 57% higher than in the provincial capital.37 Despite efforts to redress this situation, food costs remain very high and often inaccessible to many Nunavik families who must resort to reducing the amount of food supplies or buying products of lower nutritional quality,38 which compromises health and well-being.36,37,39In a study conducted among low-income families in the United States, Cutts et al.40 found a higher risk of food insecurity and child food insecurity in households with higher housing insecurity. In their study, crowding and multiple moves were considered as indicators of housing insecurity. This association was independent of maternal and family characteristics such as education and household employment. In a recent study involving Inuit households from Nunavut, in the eastern Canadian Arctic, Huet et al.41 reported higher food insecurity among Inuit living in overcrowded households and in houses requiring major repairs. This observation, however, was based on bivariate associations between housing conditions and food insecurity and did not account for other factors such as socioeconomic conditions. These studies nonetheless suggest that food insecurity is not only explained in terms of low socioeconomic status and poverty.40,42We examined whether household crowding was associated with food insecurity among Inuit families with school-aged children, independently of socioeconomic disadvantage.  相似文献   
102.
103.

Background

Although prenatal methylmercury exposure has been linked to poorer intellectual function in several studies, data from two major prospective, longitudinal studies yielded contradictory results. Associations with cognitive deficits were reported in a Faroe Islands cohort, but few were found in a study in the Seychelles Islands. It has been suggested that co-exposure to another contaminant, polychlorinated biphenyls (PCBs), may be responsible for the positive findings in the former study and that co-exposure to nutrients in methylmercury-contaminated fish may have obscured and/or protected against adverse effects in the latter.

Objectives

We aimed to determine the degree to which co-exposure to PCBs may account for the adverse effects of methylmercury and the degree to which co-exposure to docosahexaenoic acid (DHA) may obscure these effects in a sample of Inuit children in Arctic Québec.

Methods

IQ was estimated in 282 school-age children from whom umbilical cord blood samples had been obtained and analyzed for mercury and other environmental exposures.

Results

Prenatal mercury exposure was related to poorer estimated IQ after adjustment for potential confounding variables. The entry of DHA into the model significantly strengthened the association with mercury, supporting the hypothesis that beneficial effects from DHA intake can obscure adverse effects of mercury exposure. Children with cord mercury ≥ 7.5 μg/L were four times as likely to have an IQ score < 80, the clinical cut-off for borderline intellectual disability. Co-exposure to PCBs did not alter the association of mercury with IQ.

Conclusions

To our knowledge, this is the first study to document an association of prenatal mercury exposure with poorer performance on a school-age assessment of IQ, a measure whose relevance for occupational success in adulthood is well established. This association was seen at levels in the range within which many U.S. children of Asian-American background are exposed.

Citation

Jacobson JL, Muckle G, Ayotte P, Dewailly É, Jacobson SW. 2015. Relation of prenatal methylmercury exposure from environmental sources to childhood IQ. Environ Health Perspect 123:827–833; http://dx.doi.org/10.1289/ehp.1408554  相似文献   
104.
AIDS and Behavior - This study describes the acceptability of a rectal microbicide gel formulation using dapivirine (DPV) among men and women from two countries (United States and Thailand)...  相似文献   
105.
Effects of ouabain on intestinal oxygen consumption   总被引:1,自引:0,他引:1  
  相似文献   
106.
Uterine estrogen receptor in rats during pubescence and the estrous cycle   总被引:2,自引:0,他引:2  
C Lee  H I Jacobson 《Endocrinology》1971,88(3):596-601
  相似文献   
107.
108.
A current issue in alcohol research is whether a "neurobehavioral profile" can be identified for prenatal alcohol exposure, even when dysmorphic features are not present, or whether comparable neurobehavioral deficits are detected when damage is incurred by numerous neurotoxicants to which the fetus is exposed during a common developmental period. Failure to detect such differences may, in part, be an artifact of the global developmental tests used to assess outcome. Cognitive effects of prenatal exposure to three different teratogens [polychlorinated biphenyls (PCBs), alcohol, and cocaine] are examined to determine whether exposure to each substance results in a common or different pattern of impairment on the same set of newer, more narrow band infant tests. Comparison of findings from three independent cohorts indicate that PCB exposure was related to poorer recognition memory on the Fagan Test of Infant Intelligence (FTII) in Michigan infants exposed prenatally to PCB-contaminated fish, whereas prenatal alcohol exposure was unrelated to recognition memory but to slower processing speed on a new FTII measure and slower reaction time on Haith's Visual Expectancy Paradigm (VExP) in our Detroit alcohol-exposed infants. Preliminary findings from a new study of infants recently born to Taiwanese women accidentally contaminated with sizable amounts of PCBs indicate recognition memory deficits, confirming our Michigan findings, but no processing speed effects on the FTII. Recent findings from our Detroit cohort suggest that heavy prenatal cocaine exposure is related to poorer recognition memory on the FTII, but faster reaction times on the VExP, a pattern different from that seen for either PCBs or alcohol.  相似文献   
109.
Thirty-four ambulatory medical patients who had used minor tranquilizers for varying lengths of time were interviewed to determine their medical and psychiatric statuses, and to learn their own perspective of their medical care. The population was elderly of lower socioeconomic status, and chronically ill (a significant minority with serious and disabling illness). Depressive equivalents, depression, and anxiety were prominent, but clinical states requiring psychiatric care were not. Slightly less than one-half were alcoholic. Forty-one percent took the medications for target symptoms other than anxiety, and 76% believed these agents were efficacious. Chronic users had significantly more chronic medical illness, and significantly more somatization, anxiety, and fatigue.  相似文献   
110.
Action spectra were determined for neoplastic transformation, production of pyrimidine dimers, and lethality in Syrian hamster embryo cells. Of wavelengths between 240 and 313 nm, the most effective were 265 and 270. The relative sensitivities per quantum for transformation, pyrimidine dimer production, and lethality were essentially the same at each of the wavelengths tested. This action spectrum for transformation, which is relevant to carcinogenesis, is similar to spectra obtained previously by measuring other cellular responses in either microbial or mammalian systems. Because the action spectra for cytotoxicity and transformation are the same as the spectrum for dimer production, DNA is suggested as the target for all these processes.  相似文献   
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