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31.
Nearly 50,000 new cases of primary hyperparathyroidism (PHPT) are diagnosed annually in the United States. Most information about the disease focuses on the white population. We evaluated African American (AA) and white patients at our tertiary care university medical center to determine whether there was a racial difference in presentation of PHPT. A retrospective chart review of patients treated surgically for PHPT between 1997 and 2002 was performed. Demographic data, laboratory values, objective symptoms, surgical procedure, and histologic findings were recorded. The AA participants were matched to whites by age and gender. The effect of race was adjusted for the matching variables by including them in regression models. ANOVA chi2 tests were performed on the race effects. Thirty-six (14.4%) of the 286 patients treated for PHPT at Wake Forest University Baptist Medical Center during this 5-year period were AA. There was no difference in serum calcium or presence of objective symptoms, but PTH levels were significantly higher for blacks (207.5 vs 143.5 pg/mL; P = 0.02). In our study, AA patients had significantly higher parathyroid hormone levels at time of surgical intervention but did not present with a difference in symptoms or more advanced disease. Further research is recommended to characterize ethnic differences in patients with PHPT.  相似文献   
32.
Although adolescents are often curious about cigarettes and anxious to "try" smoking, they are unsure about what engaging in the act of smoking will mean. Most adolescents who experiment with smoking do not set out to become addicted to tobacco. Using a grounded theory approach, the authors examined the process youth undergo to regain control over their smoking. Accounts of early smoking experiences suggest that youth undergo a process to control tobacco use that includes (a) determining if smoking is a problem, (b) "crossing the line" of acceptable tobacco use, and (c) implementing strategies to regain control of smoking. The findings of this study lay the basis for the development of harm reduction approaches that facilitate youth's propensity to control their tobacco use.  相似文献   
33.
Abstract Periprosthetic bone remodeling, and its evaluation, are the keys of long-term survival of cementless total hip arthroplasty. Dual energy X-ray absorptiometry (DEXA) is the most accurate method to measure bone mineral density, evaluating the effects of bone-prosthesis interactions. We studied, 4 years after implantation, 10 patients who underwent total hip arthroplasty with the CFP prosthetic stem and TOP acetabular cup (Waldemar Link, Hamburg, Germany). Our results demonstrate minimal periprosthetic bone loss compared to that normally observed with conventional stems. A few cases exhibited an increase in BMD. We believe that primary stability, prosthetic design, preservation of natural neck anteversion and off-set, better function related to muscle lever arm, and physiological bone loading with natural stress distribution are the keys of this succesful mini-invasive total hip replacement system.  相似文献   
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35.
The National Tobacco Control Best Practices Working Group convened a two-day workshop to support best practices in evaluation of comprehensive tobacco control strategies. A Better Practices Model, aimed at developing a self-correcting system for best practices, guided the workshop content and process. Organizers intended to identify a common surveillance and monitoring framework for tobacco control strategies in Canada by first building strong working relationships between 44 decision-makers, practitioners and researchers from 12 Canadian jurisdictions. Participants identified needs and recommendations related to increased understanding and use of uniform evaluation strategies, building capacity, and recognition of the complexity of the task of evaluating comprehensive tobacco control strategies. The workshop highlighted the need for increased communication to facilitate understanding across the different sectors of participants. It also identified the potential benefits of harmonization in evaluation of tobacco control strategies across jurisdictions. Priority actions include forming a national team to agree on a model for evaluation, conducting an environmental scan for indicators, planning evaluation / monitoring and research agendas and determining roles for various stakeholders.  相似文献   
36.
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge.  相似文献   
37.
Introduction: Osteoporosis is a common skeletal disease with serious consequences due to osteoporotic fractures and high costs to society for post-fracture care. Most patients at high risk for fracture are not receiving care to reduce fracture risk. The osteoporosis treatment gap has reached crisis proportions. Strategies to reduce the treatment gap include systematic methods for identifying and treating high risk patients, better education of patients and healthcare providers, better use of currently available drugs, and development of new drugs to treat osteoporosis.

Areas covered: Two osteoanabolic agents with novel mechanisms of action have recently completed phase 3 clinical trials. The efficacy and safety findings of these studies are reviewed. Abaloparatide, a synthetic analog of parathyroid hormone-related protein, has received regulatory approval for the treatment of postmenopausal women with osteoporosis at high risk for fracture. Romosozumab, a humanized monoclonal antibody to sclerostin, an endogenous inhibitor of bone formation, is under regulatory review.

Expert opinion: Osteoanabolic therapy for osteoporosis can restore, at least in part, the degradation of bone microarchitecture that is a hallmark of this disease. The emergence of new osteoanabolic compounds expands the treatment options for patients at high risk for fracture.  相似文献   

38.

Introduction

School characteristics may account for some of the variation in smoking prevalence among schools. The purpose of this study was to investigate the relationships between characteristics of school tobacco policies and school smoking prevalence. We also examined the relationship between these characteristics and individual smoking status.

Methods

Tobacco policy data were collected from schools in 10 Canadian provinces during the 2004-2005 school year. Written tobacco policies were collected from each school to examine policy intent, and school administrators were surveyed to assess policy enforcement. Students in grades 5 through 9 completed the Youth Smoking Survey to assess smoking behaviors and attitudes. We used negative binomial regression and multilevel logistic regression to predict the influence of school policies on smoking behavior at the school and student levels.

Results

School policies that explicitly stated purpose and goals predicted lower prevalence of smoking at the school and individual levels. Policies that prohibited smoking on school grounds at all times predicted lower smoking prevalence at the school level but not at the individual level.

Conclusions

For maximum effectiveness, school smoking policies should clearly state a purpose and goals and should emphasize smoking prohibition. These policies can help reduce smoking prevalence among youths and are part of a comprehensive school approach to tobacco control.  相似文献   
39.
Mann  LC; Hawes  DR; Ghods  M; Bednar  EJ; Potchen  EJ 《Radiology》1987,164(1):121-122
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography.  相似文献   
40.
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