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81.

Background and aims

There is controversy on the potentially benign nature of metabolically healthy obesity (MHO), i.e., obese persons with few or no metabolic abnormalities. So far, associations between MHO and coronary artery calcification (CAC), a measure of subclinical atherosclerosis, have mainly been studied cross-sectionally in Asian populations. We assessed cross-sectional and longitudinal MHO CAC associations in a Caucasian population.

Methods and results

In the Heinz Nixdorf Recall Study, a population-based cohort study in Germany, CAC was assessed by electron-beam tomography at baseline and at 5-year follow-up. For cross-sectional and longitudinal analyses, we included 1585 participants free of coronary heart disease at baseline, with CAC measurements at baseline and at follow-up, and with either normal weight (BMI 18.5–24.9 kg/m2) or obesity (BMI ≥30.0 kg/m2) at baseline. We used four definitions of MHO. In our main analysis, we defined obese persons as metabolically healthy if they met ≤1 of the NCEP ATP III criteria for the definition of the metabolic syndrome – waist circumference was not taken into account because of collinearity with BMI.Persons with MHO had a higher prevalence of CAC than metabolically healthy normal weight (MHNW) persons (prevalence ratio = 1.59 (95% confidence interval 1.38–1.84) for the main analysis). Persons with MHO had slightly larger odds of CAC progression than persons with MHNW (odds ratios ranged from 1.17 (0.69–1.99) to 1.48 (1.02–2.13) depending on MHO definition and statistical approach).

Conclusion

Our analyses on MHO CAC associations add to the evidence that MHO is not a purely benign health condition.  相似文献   
82.
Findings of 185 patients and 271 control subjects are presented for the assessment of work capacity in hypertensive individuals (primary hypertension); an attempt at classification by hypertensive stage is seen as an essential presupposition. The subdivision into three stages recommended by the Experts' Commission of the WHO places the effects of hypertension on the organism, especially on the heart, in the focal point. This appears justified from a prognostic, pathophysiological, and therapeutic point of view. Hemodynamics in the examined patients undergo increasing impairment in relation to the stage of hypertension with a decrease in maximum cardiac index and work capacity and an increase in myocardial oxygen requirement. Initially, only the diastolic cardiac function is impaired; however, in advanced stages, the systolic function of the heart is impaired as well. Evaluation of work capacity is usually possible from a cardiac point of view by means of noninvasive echocardiographic and spiroergometric methods. The mass/volume ratio of the left cardiac ventricle and the relationship between left ventricular muscle mass (or volume) and work capacity are especially important. Both experience characteristic changes depending on the stage of hypertension and thus permit precise determination of work capacity, progress controls, and delineation from physiological cardiac hypertrophy (athletic heart).  相似文献   
83.
OBJECTIVE: To show a possible association between parvovirus B19 infection and the presence of antiphospholipid antibodies (aPL) in patients with rheumatic diseases. METHODS: Serum samples obtained from 88 children with various forms of juvenile rheumatic disease and from 40 adults with systemic lupus erythematosus, the antiphospholipid syndrome, or other rheumatic disease, who had previously been tested and shown to be positive for IgG aPL, were analyzed for the presence of B19 DNA, for antibodies against the B19 viral proteins VP1, VP2, and NS1, and for IgG aPL (anticardiolipin, anti-beta(2)-glycoprotein I, and antiphosphatidylserine). As controls, serum samples obtained from 135 children with noninflammatory bone diseases or growth retardation were also analyzed. RESULTS: Twenty-four (27%) of the 88 children with rheumatic diseases had detectable amounts of IgG aPL. Fourteen (58%) of these 24 IgG aPL-positive patients showed IgG against VP1/VP2 and viral genomes, indicating the presence of acute (2 patients) or persistent (12 patients) infection. Past parvovirus B19 infection was identified in 7 (29%) of 24 IgG aPL-positive children, as indicated by VP1/VP2-specific IgG in the absence of viral DNA. Three (12%) of 24 IgG aPL-positive children had not been infected with B19. Sixty-nine (51%) of 135 control children displayed VP1/VP2-specific IgG. Three (2%) of these 135 children were IgG aPL positive (2 children had past parvovirus B19 infection, and 1 was negative for parvovirus B19). Analysis of the parvovirus B19 status of 40 adult IgG aPL-positive patients showed that 33 (83%) were anti-IgG VP1/VP2-positive, and viral DNA was detected in 11 patients (28%). Ten of these 11 viremic patients were in the subgroup of 28 IgG aPL-positive SLE patients. CONCLUSION: Antiphospholipid antibodies are preferentially found in serum of children with juvenile idiopathic arthritis who have been previously infected with parvovirus B19 and have established, persistent infection. Adult patients with IgG aPL positivity have a high incidence of persistent parvovirus B19 infection. We conclude that parvovirus B19 might be directly involved in the elicitation of autoimmune reactions partly mediated by aPL.  相似文献   
84.
Pathogenic mitochondrial DNA (mtDNA) point mutations are associated with a wide range of clinical phenotypes, often involving multiple organ systems. We report two patients with isolated myopathy owing to novel mt-tRNAAla variants. Muscle biopsy revealed extensive histopathological findings including cytochrome c oxidase (COX)-deficient fibres. Pyrosequencing confirmed mtDNA heteroplasmy for both mutations (m.5631G>A and m.5610G>A) whilst single-muscle fibre segregation studies (revealing statistically significant higher mutation loads in COX-deficient fibres than in COX-positive fibres), hierarchical mutation segregation within patient tissues and decreased steady-state mt-tRNAAla levels all provide compelling evidence of pathogenicity. Interestingly, both patients showed very high-mutation levels in all tissues, inferring that the threshold for impairment of oxidative phosphorylation, as evidenced by COX deficiency, appears to be extremely high for these mt-tRNAAla variants. Previously described mt-tRNAAla mutations are also associated with a pure myopathic phenotype and demonstrate very high mtDNA heteroplasmy thresholds, inferring at least some genotype:phenotype correlation for mutations within this particular mt-tRNA gene.  相似文献   
85.
Background: Indoor air concentrations of polychlorinated biphenyls (PCBs) in some buildings are one or more orders of magnitude higher than background levels. In response to this, efforts have been made to assess the potential health risk posed by inhaled PCBs. These efforts are hindered by uncertainties related to the characterization and assessment of source, exposure, and exposure-response.Objectives: We briefly describe some common sources of PCBs in indoor air and estimate the contribution of inhalation exposure to total PCB exposure for select age groups. Next, we identify critical areas of research needed to improve assessment of exposure and exposure response for inhaled PCBs.Discussion: Although the manufacture of PCBs was banned in the United States in 1979, many buildings constructed before then still contain potential sources of indoor air PCB contamination. In some indoor settings and for some age groups, inhalation may contribute more to total PCB exposure than any other route of exposure. PCB exposure has been associated with human health effects, but data specific to the inhalation route are scarce. To support exposure–response assessment, it is critical that future investigations of the health impacts of PCB inhalation carefully consider certain aspects of study design, including characterization of the PCB mixture present.Conclusions: In certain contexts, inhalation exposure to PCBs may contribute more to total PCB exposure than previously assumed. New epidemiological and toxicological studies addressing the potential health impacts of inhaled PCBs may be useful for quantifying exposure–response relationships and evaluating risks.Citation: Lehmann GM, Christensen K, Maddaloni M, Phillips LJ. 2015. Evaluating health risks from inhaled polychlorinated biphenyls: research needs for addressing uncertainty. Environ Health Perspect 123:109–113; http://dx.doi.org/10.1289/ehp.1408564  相似文献   
86.
Community-based strategies that foster frequent contact between caregivers of children under five and provide credible sources of health information are essential to improve child survival. Care Groups are a community-based implementation strategy for the delivery of social and behavior change interventions. This study assessed if supervision of Care Group activities by Ministry of Health (MOH) personnel could achieve the same child health outcomes as supervision provided by specialized non-governmental organization (NGO) staff. The study was a pretest-posttest quasi-experimental design implemented in Burundi. A total of 45 MOH-led Care Groups with 478 Care Group Volunteers (CGVs) were established in the intervention area; and 50 NGO-led Care Groups with 509 CGVs were formed in the comparison area. Data were collected from 593 and 700 mothers of children 0-23 months at baseline and endline, respectively. Pearson’s chi-squared test and difference-in-difference analysis assessed changes in 40 child health and nutrition outcomes. A qualitative process evaluation was also conducted midway through the study. The MOH-led Care Group model performed at least as well as the NGO-led model in achieving specific child health and nutrition outcomes. Mothers of children 0-23 months in the intervention and comparison sites reported similar levels of knowledge and practices for 38 of 40 dependent variables measured in the study, and these results remained unchanged after accounting for differences in the indicator values at baseline. Process monitoring data confirmed that the MOH-led Care Group model and the NGO-led Care Group model were implemented with similar intervention strength. The study demonstrated that behavior change interventions traditionally led by NGOs can be implemented through the existing MOH systems and achieve similar results, thereby increasing the potential for sustainable child health outcomes. Future research on the MOH-led Care Group model is required to systematically document all inputs and monetary costs borne by the MOH to implement the model.  相似文献   
87.
88.
The effect of orally given diethystilboestroldiphophate (DES) and 17alpha-ethinyl-oestradiol-3-methylether (EEM) on plasma progesterone levels was studied. Both compounds were administered for 5 days to 5 women in daily doses of 60 mg (DES) and 30 mg (EEM). The fully informed volunteers were found to have a normal menstrual cycle before the study. The mean corpus luteum phase (corpus luteum phase = days between LH surge and onset of menstruation) of all control cycles lasted 12.8 days. Daily plasma samples were collected for radioimmunoassay (RIA) of progesterone, immunoreactive oestrogens and LH. After a control cycle the first treatment was carried out with DES. The third and the fifth cycle were control cycles again. The EEM-treatment was done in the fourth cycle. Although the effect of the two compounds was different, a dependence of the age of the corpus luteum (CL) could be demonstrated for both. DES-treatment lowered plasma progesterone levels during administration. This effect was only demonstrable if the treatment was begun on the day of the LH-peak. The length of the CL-phase remained unaltered. EEM-treatment if started on the day of the LH surge, suppressed corpus luteum function in the late luteal phase. If the treatment was started later, the effect was less pronounced. The administration of both compounds did not shorten the time between ovulation and the next bleeding. After DES-treatment this interval was not altered. After EEM-treatment the subsequent bleeding was even delayed depending on slowly decreasing levels of plasma oestrogens.  相似文献   
89.
90.
Chronic infantile neurologic, cutaneous, articular (CINCA) syndrome is characterized by fever, chronic meningitis, uveitis, sensorineural hearing loss, urticarial skin rash, and a deforming arthritis. In the CIAS1 gene of many but not all CINCA patients, disease-associated mutations have been found recently. We here describe two such patients from Germany. One of them, a 3-yr-old boy, has a 1709A-->G, Y570C, mutation, which has previously been described to cause CINCA syndrome. His clinical course is very severe and no satisfying response has been achieved even with high doses of local and systemic steroids. The other patient has a somewhat milder clinical course and considerable improvement could be accomplished with moderate and low doses of steroids. In her CIAS1 gene we have found a 1043C-->T, T348M, mutation, which has only been detected in Muckle-Wells syndrome before. Our results suggest that the severity of symptoms in CINCA patients may be influenced by the underlying mutation in the CIAS1 gene. Furthermore, our observations support the view that CINCA syndrome and Muckle-Wells syndrome are essentially the same disease with different degrees of severity.  相似文献   
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