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There is limited information on the relationship between parental practices that specifically discourage current cigarette smoking and adolescent cessation, and how this relationship varies by age. Among 1629 adolescent smokers, self-reported receipt of parental communication not to smoke was significantly and positively associated with readiness to quit. The strength and significance of this association decreased from early to middle adolescence and was not significant in late adolescence.  相似文献   
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Peripheral quantitative computed tomography (pQCT) has mainly been used as a research tool in children. To evaluate the clinical utility of pQCT and formulate recommendations for its use in children, the International Society of Clinical Densitometry (ISCD) convened a task force to review the literature and propose areas of consensus and future research. The types of pQCT technology available, the clinical application of pQCT for bone health assessment in children, the important elements to be included in a pQCT report, and quality control monitoring techniques were evaluated. The review revealed a lack of standardization of pQCT techniques, and a paucity of data regarding differences between pQCT manufacturers, models and software versions and their impact in pediatric assessment. Measurement sites varied across studies. Adequate reference data, a critical element for interpretation of pQCT results, were entirely lacking, although some comparative data on healthy children were available. The elements of the pQCT clinical report and quality control procedures are similar to those recommended for dual-energy X-ray absorptiometry. Future research is needed to establish evidence-based criteria for the selection of the measurement site, scan acquisition and analysis parameters, and outcome measures. Reference data that sufficiently characterize the normal range of variability in the population also need to be established.  相似文献   
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Infections are the most common complication in patients receiving treatment for cancer with neutropenia being the primary risk factor for the development of an infection. In the neutropenic patient, bacteremia remains a significant cause of mortality. Although the literature reports that prompt empiric antibiotic therapy to prevent death caused by virulent organisms is the standard of care, the literature fails to identify what prompt antibiotic administration means. Door/fever-to-patient antibiotic delivery was evaluated as a quality control measure in a new children's hospital. Initially, door/fever-to-patient time was significantly delayed. Collaboration between pharmacy, hospital bed control, medical, and nursing staff resulted in many changes in practice by all groups. As a result, the goal for prompt antibiotic delivery of thirty minutes or less is now achievable.  相似文献   
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INTRODUCTION: Limited access to medical care has resulted in large numbers of patients seeking primary care for non-emergent emergency conditions in emergency departments. This influx of patients is contributing to overcrowding and delays in care for patients with emergencies. In response, a system was implemented in which persons with non-emergent medical conditions, following a medical screening examination, did not receive further ED assessment or treatment and instead were referred to community resources. The purpose of this study was to describe the characteristics of individuals who were referred to community-based services, their condition after 72 hours, and their use of follow-up health care services. METHODS: All referred cases (n=225) were reviewed for chief complaint and demographics. Phone contact was attempted after 72 hours to determine the person's condition and if community resources were utilized. RESULTS: Of the 225 cases, 52% were female, with a mean age of 33 years. Their most common chief complaints were extremity problems (16%), toothache (9%), and medication refill (8%). Follow-up phone contact was successful with 82 people (37%) an average of 14 days after their ED visit. The majority (55%) reported their condition had improved; 39%were unchanged, and 6% were worse. Thirty-one people(40%) accessed community resources and 8 (26%) returned to another emergency department. No clinically significant associations were found between patient demographics and use of community resources. DISCUSSION: Most people who were successfully contacted for follow-up and who had come to the emergency department with non-emergent chief complaints did not access community resources and their condition frequently improved. Additional studies, with improved follow-up, are needed before suggesting that referring individuals to community resources is an acceptable practice.  相似文献   
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In an effort to develop a method of tissue injury which would provide a model for the study of axonal regrowth in adult mammalian central nervous system (CNS), we have analyzed the effects of freezing in the dorsal columns of more than 200 rat spinal cords. The effects of temperature and time of exposure upon the size, shape, distribution and histologic characteristics of the lesion have been assessed during the first seven days following the injury. The upper threshold for injury occurs at -3 degrees C for 15 minutes. Between -3 degrees C and -12 degrees C the tissue changes vary in extent and characteristics. Selective damage to axons and myelin occurs with sparing of the supportive cells followed by proliferation of a cellular matrix. At seven days, the lesions produced by -8 degrees C for 15 to 60 minutes have neither axons nor myelin sheaths and consist of a dense cellular matrix of macrophages and presumed glial cells. With these tissue characteristics, and the preservation of tissue continuity without obstructive barriers, this model would appear to be potentially suitable for the study of axonal regrowth potential in mammalian CNS.  相似文献   
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Anteroposterior lip positions of the most-favored Japanese facial profiles.   总被引:1,自引:0,他引:1  
INTRODUCTION: Soft tissue analysis is a basic tool in planning orthodontic treatment. However, the components of a well-balanced Japanese facial profile have not yet been established. The purpose of this study was to assess the most-favored or most well-balanced profile from a series of facial silhouettes with varying anteroposterior lip positions by a group of Japanese orthodontists and a group of young adult Japanese dental students. METHODS: Average female and male profiles were constructed from the profiles of 30 Japanese men and women with normal occlusions. The lips in each average profile were protruded or retruded in 1-mm increments, and the 13 images were arranged with the average profile in the center. Forty two orthodontists and 42 dental students were asked to select the 3 most-favored, well-balanced profiles for each sex and rank them in order of preference. RESULTS: Both the orthodontists and the students preferred a profile with slightly retruded lips. The dental students favored a more retruded lip position for women. The least-favored profile was the most protrusive. CONCLUSIONS: These findings suggest that Japanese orthodontists and young adults prefer a retruded profile, even though Japanese profiles have historically been characterized by more convex facial features.  相似文献   
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