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排序方式: 共有111条查询结果,搜索用时 31 毫秒
81.
Jamie F. Chriqui Julien Leider Juliana F. W. Cohen Marlene Schwartz Lindsey Turner 《Nutrients》2021,13(1)
Under the U.S. Department of Agriculture’s Smart Snacks in School standards, beverages sold in schools are restricted to water, flavored or unflavored non-fat milk or unflavored low-fat milk (and milk alternatives), and 100% fruit and vegetable juices; and, at the high school level, diet (≤10 kcal), low-calorie (≤60 kcal), and caffeinated beverages may also be sold. Using data from the School Nutrition and Meal Cost Study, this study examined whether secondary school student beverage consumption was associated with school-level à la carte and vending machine beverage availability, controlling for district, school, and student characteristics. On average, most beverages sold in middle schools (84.54%) and high schools (74.11%) were Smart Snacks compliant; while 24.06 percent of middle school students and 14.64 percent of high school students reported consuming non-compliant beverages, including non-compliant milk, fruit drinks, and sports or energy drinks. School beverage availability was not related to consumption among middle school students; however, high school students were less likely to consume non-compliant beverages when enrolled in schools that sold a higher proportion of compliant beverages (Range: OR = 0.97–0.98, 95% CI = 0.95, 1.00). Findings from this study build upon prior research illustrating the role that schools can play in influencing student dietary intake. 相似文献
82.
Jonathon P. Leider Elizabeth Harper Ji Won Shon Katie Sellers Brian C. Castrucci 《American journal of public health》2016,106(10):1782-1788
Objectives. To use data on the governmental public health workforce to examine demographics and elucidate drivers of job satisfaction and intent to leave one’s organization.Methods. Using microdata from the 2014 Federal Employee Viewpoint Survey and 2014 Public Health Workforce Interests and Needs Survey, we drew comparisons between federal, state, and local public health staff. We fitted logistic regressions to examine correlates of both job satisfaction and intent to leave one’s organization within the coming year.Results. Correlates of job satisfaction included pay satisfaction, organizational support, and employee involvement. Approximately 40% of federal, state, and local staff said they were either considering leaving their organization in the next year or were planning to retire by 2020.Conclusions. Public health practitioners largely like their jobs, but many are dissatisfied with their pay and are considering working elsewhere. More should be done to understand the determinants of job satisfaction and how to successfully retain high-quality staff.Public Health Implications. Public health is at a crossroads. Significant turnover is expected in the coming years. Retention efforts should engage staff across all levels of public health.The mission of public health is to prevent disease, promote health, and prolong life for the United States population through the core functions of public health (assessment, policy development, and assurance).1–4 To fulfill this mission, there are approximately 300 000 public health employees at the federal, state, and local levels.5 The governmental public health workforce comprises federal (20%), state (30%), and local health department employees (50%).5 Each of these groups makes essential contributions to the public health enterprise. A recent study found that 38% of state health agency (SHA) employees intend to leave governmental public health before 2020.6 However, the number of local and federal public health employees planning to leave is not well studied,6 although the consequences of employee turnover are well documented. High levels of employee turnover lead to a loss of expertise and institutional knowledge, high costs to the organization, and a decrease in organizational performance.7–9 Retaining institutional knowledge through employees is especially important in the public sector, which undergoes high levels of change.10 Additionally, the cost to recruit and train new employees can amount to 50% to 200% of the employee’s annual salary.11 Furthermore, organizational and individual performance suffers because workers who intend to leave are less efficient and effective in their job roles.12Studies show that a variety of factors contribute to turnover and can be categorized into external, work-related, and personal factors.7,12,13 Two external factors related to intent to leave are perception of job alternatives, which is positively related to turnover, and the presence of a union, which is negatively related to turnover.7,9,12–16 Pay satisfaction was consistently identified as an important factor in intent to leave; 29 of 32 studies in a meta-analysis showed a negative association.13 Finally, personal factors such as age, education, number of dependents, health status, and race/ethnicity have been significantly related to turnover and intent to leave.13 Although there are many contributors to workers’ intent to leave, a review of the literature shows a consistently negative relationship between worker turnover and job satisfaction.14,17,18 Although the field is beginning to study this area among SHA workers,14,19 relatively little is known about local or federal level job satisfaction or intent to leave. We address that gap. 相似文献
83.
D R Mehlisch A S Leider W E Roberts 《Oral surgery, oral medicine, and oral pathology》1990,70(6):685-692
Samples of the bone/graft interface were evaluated histologically in five patients 1 year after mandibular ridge augmentation with a composite of hydroxylapatite particles in a matrix of purified fibrillar collagen (HA/PFC). The resulting defects were refilled with HA/PFC after the biopsy specimens were obtained. Histologic examination of the specimens yielded no evidence of purified fibrillar collagen. Hydroxylapatite particles were surrounded by dense fibrous host connective tissue, trabeculae of woven and lamellar bone, or both. HA/PFC was found to be biocompatible with human tissue and receptive to direct bone apposition on the hydroxylapatite particles. 相似文献
84.
B cell receptor signaling threshold regulates negative selection of autoreactive B cells and determines the mechanism of B cell tolerance. Using mice carrying immunoglobulin transgene specific for MHC class I antigen K(k) (3-83 Tg mice), and IL-7-driven bone marrow (BM) culture system, we have previously shown that receptor editing is a major mechanism in B cell tolerance. To test the role of BCR signaling competence on the induction of tolerance-mediated receptor editing, we crossed the 3-83 Tg mice with mice deficient in CD45, a protein tyrosine phosphatase that functions asa positive regulator of the BCR signaling. We found that in the absence of self-antigen allelic exclusion is efficiently imposed in 3-83 Tg CD45(-/-) mice, although numbers of peripheral B cells are reduced. Using our BM culture system, we show here that immature 3-83 Tg CD45(-/-) B cells encountering self-antigen are developmentally arrested and undergo secondary light chain recombination and receptor editing, not different than CD45-sufficient cells. Thus, lack of CD45 does not abolish the receptor editing competence in immature B cells encountering high avidity membrane-bound antigen. 相似文献
85.
Hicks RR Boggs A Leider D Kraemer P Brown R Scheff SW Seroogy KB 《Restorative neurology and neuroscience》1998,12(1):41-47
Previous studies have suggested that brain-derived neurotrophic factor (BDNF) is involved in memory and learning, and may be neuroprotective following various brain insults. Exercise has been found to increase BDNF mRNA levels in various brain regions, including specific subpopulations of hippocampal neurons. In the present study, we were interested in whether following traumatic brain injury, exercise could increase BDNF mRNA expression, attenuate neuropathology, and improve cognitive and neuromoter performance. We subjected adult male Sprague-Dawley rats to a fluid percussion brain injury, followed by either 18 days of treadmill exercise or handling. Spatial memory was evaluated in a Morris Water Maze (MWM) and motor function was evaluated with a battery of neuromotor tests. Neuropathology was evaluated by measuring the cortical lesion volume and the extent of neuronal loss in the hipocampus. Expression of BDNF mRNA in the hippocampus was assessed with in situ hybridization and densitometry. Hybridization signal for BDNF mRNA was significantly increased bilaterally in the exercise group in hippocampal regions CA1 and CA3 (p<0.05), but not in the granule cell layer of the dentate gyrus. No significant differences were observed between the groups in neuropathology, spatial memory, or motor performance. This study suggests that after traumatic brain injury, exercise elevates BDNF mRNA in specific regions of the hippocampus. 相似文献
86.
87.
C M Stewart R E Watson L R Eversole W Fischlschweiger A S Leider 《Oral surgery, oral medicine, and oral pathology》1988,65(4):427-435
To investigate the histogenesis of the granular cell, a large series of granular cell tumors was studied for clinical and histopathologic features with emphasis on immunocytochemical markers. The nongingival granular cell tumors (NGGCT) were found to be more prevalent among females than males by a ratio of 2:1 and arose on the tongue (67%), the buccal mucosa (13%), the lips (8%), the soft palate (6%), and other sites (6%). With the use of the avidin-biotin-peroxidase method, polyclonal rabbit antisera were employed. The antisera were directed to the following antigens: S-100 protein, myoglobin, myosin, actin, desmin, alpha-1-antitrypsin, and muramidase. Results indicated that granular cell tumors are not homogenous for immunocytochemical markers. Nongingival granular cell tumors were universally positive for S-100 protein and failed to exhibit immunoreactivity for myogenous or histiocytic markers. Alternatively, the gingival granular cell tumor of infancy was negative for all markers, whereas rhabdomyoma was reactive with myogenous markers and a subpopulation of tumor cells displayed S-100 protein immunoreactivity. The granular cell ameloblastoma was reactive only with antiserum to alpha-1-antitrypsin. Ultrastructurally, granular cells from one of two NGGCT showed a direct evolution from skeletal muscle fibers. It is concluded that the oral NGGCT is a tumor positive for S-100 protein that may arise from muscle or nerve sheath. 相似文献
88.
A Buchner W M Carpenter P W Merrell A S Leider 《Oral surgery, oral medicine, and oral pathology》1991,71(2):131-136
Lingual mandibular salivary gland defects in the posterior part of the mandible are not uncommon. Analogous defects in the anterior region, however, are rare, and the four new cases presented in this report bring the total number of reported cases up to 24. The purpose of the present study was to review and analyze the clinical, radiographic, and histologic features of the previously reported cases together with those of the present study. The majority of these defects were located in the cuspid and/or premolar area and were diagnosed in men in their fifth and sixth decades of life. Almost all defects contained normal salivary gland tissue. The differential diagnosis, treatment, and pathogenesis of these defects are discussed. 相似文献
89.
90.