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Young women in South Africa are at high risk for HIV infection. Cash transfers offer promise to reduce HIV risk. We present the design and baseline results from HPTN 068, a phase III, individually randomized trial to assess the effect of a conditional cash transfer on HIV acquisition among South African young women. A total of 2533 young women were randomized to receive a monthly cash transfer conditional on school attendance or to a control group. A number of individual-, partner-, household- and school-level factors were associated with HIV and HSV-2 infection. After adjusting for age, all levels were associated with an increased odds of HIV infection with partner-level factors conveying the strongest association (aOR 3.05 95 % CI 1.84–5.06). Interventions like cash transfers that address structural factors such as schooling and poverty have the potential to reduce HIV risk in young women in South Africa.  相似文献   
23.
The temporal coordination of neural activity within structural networks of the brain has been posited as a basis for cognition. Changes in the frequency and similarity of oscillating electrical potentials emitted by neuronal populations may reflect the means by which networks of the brain carry out functions critical for adaptive behavior. A computation of the phase relationship between signals recorded from separable brain regions is a method for characterizing the temporal interactions of neuronal populations. Recently, different phase estimation methods for quantifying the time‐varying and frequency‐dependent nature of neural synchronization have been proposed. The most common method for measuring the synchronization of signals through phase computations uses complex wavelet transforms of neural signals to estimate their instantaneous phase difference and locking. In this article, we extend this idea by introducing a new time‐varying phase synchrony measure based on Cohen's class of time–frequency distributions. This index offers improvements over existing synchrony measures by characterizing the similarity of signals from separable brain regions with uniformly high resolution across time and frequency. The proposed measure is applied to both synthesized signals and electroencephalography data to test its effectiveness in estimating phase changes and quantifying neural synchrony in the brain. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
24.
Transient myeloproliferative disorder (TMD) typically presents with pancytopenia, hepatosplenomegaly, and immature circulating white blood cells, and affects approximately 10 % of neonates with Down syndrome. The authors report a neonate with Down syndrome who developed acute widespread pustular eruptions as a sign of TMD. The white blood cell counts on the first day of life were markedly elevated, with blasts seen on examination of the peripheral blood smear. And the patient was noted to have a few erythematous papules and pustules especially on the face. On the following days pathergy positive crusted papules and pustules were increased and spread to trunk and extremities. Skin biopsy specimens showed pustular dermatitis, with subcorneal vesiculopustules and perivascular inflammation in superficial dermis. These lesions improved parallel with the hematologic improvement within two weeks. The authors aim to alert clinicians about this uncommon cause of vesiculopustular eruption with the present illustrative case and review the literature.  相似文献   
25.
Background: A number of different screening tests are frequently used in alcohol research, but our knowledge about the reliability of many of them is quite limited. Recently, this problem has received more attention. This article examines the test-retest reliability of one of these instruments—the Alcohol Use Disorder Identification Test (AUDIT)—in a general population sample.
Methods: A general population sample ( n = 457) was tested and, after approximately 1 month, was retested by using the AUDIT. Correlation between the two tests has been examined with the intraclass correlation coefficient and the κ coefficient in analysis of dichotomous variables. Specificity and sensitivity at a number of different cutoff scores have also been analyzed by using the first test as a criterion.
Results: On the item level, the correlations ranged between 0.6 and 0.8. The overall reliability of total AUDIT scores was 0.84. When stratified by gender, age, and consumer status, the total score reliability approximated 0.80 for all the categories except low alcohol consumers (0.51). Agreement using the recommended cutoff score of 8+ was also examined. The reliability (κ) observed in the whole sample was 0.691, which was interpreted as a substantial agreement. By this cutoff, 91% were correctly classified at retest compared with the first test. AUDIT 8+ showed higher reliability for males, young people, and moderate consumers and low reliability among low consumers. In terms of reliability, the most optimal cutoff for women turned out to be 6 or more.
Conclusions: According to these results, the test-retest reliability of AUDIT is high. The next step might be to examine to what extent the findings apply within health-care settings, which is what the test originally was designed for.  相似文献   
26.

Background

Burnout is prevalent among pediatric residents, and reducing burnout is a priority for pediatric residency programs. Understanding residents’ personal circumstances, including relationship satisfaction and perceived work-life conflict, may identify novel determinants of burnout.

Objectives

To describe intimate partner relationships among pediatric residents and examine associations among relationship satisfaction, work-life factors, and burnout.

Methods

We identified 203 partnered residents (married or in a self-identified committed, ongoing relationship) from a cross-sectional survey of 258 residents in 11 New England pediatric programs (response rate 54% of 486 surveys distributed), conducted from April through June of 2013. We analyzed associations among relationship satisfaction, work-life factors, and burnout using multivariable regression. Burnout was measured with the brief Maslach Burnout Inventory, and relationship satisfaction with the validated Relationship Assessment Scale.

Results

Burnout was reported by 40.9% of partnered respondents. The vast majority of partnered residents (n?=?167; 85.2%) reported high relationship satisfaction. Lower relationship satisfaction was not associated with burnout. Approximately half of the respondents (n?=?102; 51.5%) reported being satisfied with life as a resident. When controlling for common stressors, such as sleep deprivation, work-life measures associated with burnout included frequent perceived conflicts between personal and professional life (adjusted odds ratio, 4.35; 95% confidence interval, 1.91–9.88) and dissatisfaction with life as a resident (adjusted odds ratio, 11.74; 95% confidence interval, 4.23–32.57).

Conclusion

Low relationship satisfaction and common work-life stressors were not associated with burnout among partnered pediatric residents. However, perceived work-life conflict and dissatisfaction with resident life were strongly associated with burnout and are targets for residency programs seeking to ameliorate burnout.  相似文献   
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On the basis of observations concerning non-screen films and xerox plates a theory is proposed as to how the image quality is impaired by secondary radiation. The theory includes an explanation of why xerox plates and industrial roentgen films of a high silver content are less affected by secondary radiation than conventional roentgen films.  相似文献   
29.
BACKGROUND: Salt Lake City, Utah has seen a continuing resurgence of rheumatic fever (RF) since 1985. METHODS: emm genotyping and multilocus sequence typing of streptococcal isolates from periods of increased RF activity were performed. RESULTS: Multiple genotypes were present during 1985 and 1998, two peak years of RF activity, and in 1992, a year with reduced RF activity. emm3 and emm18.1 were present in 1985 and 1998, but not in 1992. Two other emm types, 12 and L28, were significantly elevated in 1998 (a peak RF year) over 1992 (a non-peak RF year). Allelic profiles for the emm3 and emm18.1 isolates exhibited clonality. CONCLUSIONS: During years of increased RF activity multiple emm types, including emm18.1 and emm3, were circulating in the community. During a year of decreased RF activity, emm3 and emm18.1 genotypes were absent. The clonality of the emm3 and emm18.1 types suggests that specific clones of both types are important in the resurgence of RF during these peak years. Two other genotypes, emm12 and emmL28, may also be associated with the persistence of RF in the Salt Lake City, UT area.  相似文献   
30.
Using electron microscopy, the smooth musculature of human and laboratory animal bronchi, intestine and ureters was found to contain smooth myocytes of light and dark types, which had the cytoplasm of different electron density. Both types of myocytes are characterized by a high degree of differentiation. The significant differences between light and dark myocytes were detected in the ultrastructural organization of their contractile elements. On the basis of data obtained, light and dark myocytes should be considered as mature cells in different phases of their functional activity. Some part of them, light myocytes, are in the state of "passive" contraction and may serve as a tissue functional reserve. Mutual transformation of light and dark myocytes seems to be possible and may be caused by functional requirements, which are realized at the level of tissue regulation.  相似文献   
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