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981.
OBJECTIVE: This article presents the results of a survey on preventive and health promotion (PHP) services provided by Quebec CLSCs for infants, children and youth. Two dimensions of services are examined: the diversity of PHP issues addressed and the type of clientele targeted by the CLSC team. METHODS: Questionnaire survey. RESULTS: Although identified a priori as public health priorities, many PHP issues remain less often addressed by CLSCs. This is particularly the case for activities aimed at children and youth as compared to infants. In addition, the data show that CLSC teams are less inclined to target specific clienteles; when they do so, it is more often in the context of services for infants. DISCUSSION: This study is important in that it constitutes one of the first efforts to systematically document PHP services for infants, children, and youth. In shedding new light on intervention sectors that need to be reinforced, these results should help managers and policymakers as they reflect on the role of PHP services in CLSCs within the context of health reform.  相似文献   
982.
OBJECTIVE: Our research pertains to juveniles coming under the responsibility of the Centres jeunesse du Quebec (delinquency and youth protection regional services). Some of these teenagers fled their family and made use of their social network to cope with residential instability. These youths were then in a situation of "hidden homelessness", sleeping neither in the streets nor at shelters. Two objectives are pursued: 1) a comparison of youth's and parent's evaluations of significant dimensions of their family life, and 2) an identification of the adolescents' characteristics (clinical, familial and individual) related to their "hidden homelessness". METHOD: Using bivariate analysis, a group of adolescents who had experienced homelessness was paired (on sex, age and urban or rural areas of origin) to a sample of non-homeless youths. The analysis uses both adolescents and parent/caretaker reports on measures of family characteristics and adolescent self-reports on measures of clinical and personal characteristics. FINDINGS: Our results show 1) that, in general, adolescents report a higher level of parental maltreatment and more problems related to the family dynamics and their relationship with their parents than their parents do; 2) that hidden homelessness of distressed youths is generally associated with the same familial risk factors as the ones identified by the studies concerning street youths; 3) in contrast to some other comparative studies, the homeless adolescents in our study did not differ from the non-homeless youths as to the importance of the depressive diagnostic and the use of hard drugs.  相似文献   
983.
Fortification with calcium to increase dietary intakes of this mineral is currently under evaluation in Canada. To model the potential dietary consequences of food fortification, data from a large national survey of Canadians (n = 1543) were used. Food fortification scenarios were based on reference amounts for labeling requirements. Consumption of milk, cheese and other dairy products was associated with high calcium intakes, and there was a low prevalence of inadequacy in men < 50 y old; however, other age-sex groups had lower intakes. The aim of the fortification modeling was to determine which scenario would most effectively reduce the proportion of the population with low intakes of calcium while minimizing the proportion of individuals who exceeded the tolerable upper intake level (UL). Given the correlation between energy and calcium (r = 0.60, P < 0.01), it appeared that any fortification scenario sufficient to increase the mean intake for women to near the adequate intake led to 6-7% of the men having calcium intakes above the UL. The results suggest that fortification of widely consumed foods is not a realistic way to address the issue of low calcium intakes and illustrate the need for concern about the growing use of fortification practices.  相似文献   
984.
985.
Danielsson AJ  Nachemson AL 《Spine》2001,26(5):516-525
STUDY DESIGN: This study is a follow-up investigation for a consecutive series of patients with adolescent idiopathic scoliosis treated between 1968 and 1977. In this series, 156 patients underwent surgery with distraction and fusion using Harrington rods, and 127 were treated with brace. OBJECTIVES: To determine the long-term outcome in terms of radiologic findings and curve progression at least 20 years after completion of the treatment. SUMMARY OF BACKGROUND DATA: Radiologic appearance is important in comparing the outcome of different treatment options and in evaluating clinical results. Earlier studies have shown a slight increase of the Cobb angle in brace-treated patients with time, but not in fused patients. METHODS: Of 283 patients, 252 attended a clinical and radiologic follow-up assessment by an unbiased observer (91% of the surgically treated and 87% of the brace-treated patients). This evaluation included chart reviews, validated questionnaires, clinical examination, and full-length standing frontal and lateral roentgenographs. Curve size was measured by the Cobb method on anteroposterior roentgenograms as well as by sagittal contour and balance on lateral films. The occurrence of any degenerative changes or other complications was noted. An age- and gender-matched control group of 100 individuals was randomly selected and subjected to the same examinations. RESULTS: The mean follow-up times were 23 years for surgically treated group and 22 years for brace-treated group. The deterioration of the curves was 3.5 degrees for all the surgically treated curves and 7.9 degrees for all the brace-treated curves (P < 0.001). Five patients, all brace-treated, had a curve increase of 20 degrees or more. The overall complication rate after surgery was low: Pseudarthrosis occurred in three patients, and flat back syndrome developed in four patients. Eight of the patients treated with fusion (5.1%) had undergone some additional curve-related surgical procedure. The lumbar lordosis was less in the surgically treated than in the brace-treated patients or the control group (mean, 33 degrees vs 45 degrees and 44 degrees, respectively). Both surgically treated and brace-treated patients had more degenerative disc changes than the control participants (P < 0.001), but no significant differences were found between the scoliosis groups. No statistically significant difference in terms of radiographically detectable degenerative changes in the unfused lumbar discs was found between patients fused below L3 or those fused to L3 and above (P = 0.22). A study on intra- and interobserver measurements of kyphosis, lordosis, and sagittal vertical axis on two films for each patient demonstrated that the repeatability of measuring sagittal plumbline on two different lateral radiographs, with patients moving between radiograms, was unreliable for comparison. CONCLUSIONS: Although more than 20 years had passed since completion of the treatment, most of the curves did not increase. The surgical complication rate was low. Degenerative disc changes were more common in both patient groups than in the control group.  相似文献   
986.
987.
Objectives: Few studies of smoking and cervical carcinoma have addressed the rare cervical adenocarcinomas or used DNA-based tests to control for human papillomavirus (HPV) infection. Methods: This multicenter case–control study included 124 adenocarcinoma cases, 307 community controls (matched on age, race, and residence to adenocarcinoma cases), and 139 squamous carcinoma cases (matched on age, diagnosis date, clinic, and disease stage to adenocarcinoma cases). Participants completed risk-factor interviews and volunteered cervical samples for PCR-based HPV testing. Polychotomous logistic regression generated adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for both histologic types. Results: Eighteen percent of adenocarcinoma cases, 43% of squamous carcinoma cases, and 22% of controls were current smokers. After control for HPV and other questionnaire data, adenocarcinomas were consistently inversely associated with smoking (e.g. current: OR = 0.6, 95% CI 0.3–1.1; 1 pack per day: OR = 0.7, 95% CI 0.4–1.3), while squamous carcinomas were positively associated with smoking (e.g. current: OR = 1.6, 95% CI 0.9–2.9; 1 pack per day: OR = 1.8, 95% CI 1.0–3.3). Results in analyses restricted to HPV-positive controls were similar. Conclusion: Smoking has opposite associations with cervical adenocarcinomas and squamous carcinomas. Although both histologic types are caused by HPV and arise in the cervix, etiologic co-factors for these tumors may differ.  相似文献   
988.
OBJECTIVE: The purpose of this study was to examine the association between overweight status and physical activity (PA) among gender and ethnic (Hispanic vs. non-Hispanic) sub-groups in elementary school-age children. METHODS: PA was assessed over five days using the Actigraph accelerometer in 169 fourth grade students (mean age 9.4 years; 50% female; 63% Hispanic; and 43% overweight, defined as body mass index, BMI > or = 85th percentile for age and gender) from four elementary schools in Los Angeles County, California. RESULTS: In the total sample, boys and normal weight students had higher levels of total PA (counts per minute, cpm; p<0.05). Boys spent less time in sedentary PA (p=0.02) and more time in combined moderate to vigorous PA (MVPA, p=0.01). There was a significant gender, ethnicity, and overweight interaction for total PA and MVPA (both p<0.01). MVPA and counts per minute were significantly lower in overweight non-Hispanic girls and Hispanic boys (p<0.05) and marginally lower in overweight non-Hispanic boys (p=0.10) when compared with non-overweight students, while overweight Hispanic girls were more physically active than Hispanic non-overweight girls, though the difference was non-significant (p>0.05). CONCLUSIONS: Data from the present study does not consistently support the prevailing hypothesis that overweight subjects engage in less PA. Results show overweight students engage in less PA than non-overweight students, with the exception that non-overweight Hispanic girls do not engage in more PA than their overweight peers. These results suggest the need for further investigation into the role that ethnicity and overweight status plays in PA levels, particularly among ethnic and gender sub-groups.  相似文献   
989.
Cardiovascular disease (CVD) is the leading cause of mortality in women. In fact, CVD is responsible for a third of all deaths of women worldwide and half of all deaths of women over 50 years of age in developing countries. The prevalence of CVD risk factor precursors is increasing in children. Retrospective analyses suggest that there are some clinically relevant differences between women and men in terms of prevalence, presentation, management and outcomes of the disease, but little is known about why CVD affects women and men differently. For instance, women with diabetes have a significantly higher CVD mortality rate than men with diabetes. Similarly, women with atrial fibrillation are at greater risk of stroke than men with atrial fibrillation. Historically, women have been underrepresented in clinical trials. The lack of good trial evidence concerning sex-specific outcomes has led to assumptions about CVD treatment in women, which in turn may have resulted in inadequate diagnoses and suboptimal management, greatly affecting outcomes. This knowledge gap may also explain why cardiovascular health in women is not improving as fast as that of men. Over the last decades, mortality rates in men have steadily declined, while those in women remained stable. It is also becoming increasingly evident that gender differences in cultural, behavioural, psychosocial and socioeconomic status are responsible, to various degrees, for the observed differences between women and men. However, the interaction between sex-and gender-related factors and CVD outcomes in women remains largely unknown.  相似文献   
990.
The hypothesis was tested that the absorption of labile Al in rats will increase when the Al-binding capacity of food components in the stomach is saturated. Male rats were exposed to 0, 10, 50, or 500 mg labile Al/L in acidic drinking water (pH 3) for 9 wk. The results show that labile Al in drinking water is complexed by feed constituents in the stomach of the rat in vivo, thus causing a nondetectable absorption of Al at 10 mg Al/L. An increased absorption of Al at 50 and 500 mg Al/L was associated with a saturation of the Al-binding capacity of feed components in the lumen of the stomach, causing the appearance of labile Al. Thus, the presence of labile Al in drinking water does not necessarily result in a high Al absorption when the water is ingested, since the bioavailability of labile Al is dependent both on the amount and composition of Al-binding components present in the gastrointestinal tract at the time of ingestion of the water. It is thus not possible to predict the body burden of Al in humans just by measuring the Al concentrations in drinking water. Even a further refining of the exposure measurement to include speciation of Al in the water may not markedly improve the prediction of the Al body burden. Future epidemiological studies must therefore be based on actual measurements of Al concentration in tissues or fluids from the study subjects.  相似文献   
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