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51.

Two types of sex education are generally offered in the U.S. abstinence-only and comprehensive sex education. There is no clear scientific consensus over which approach minimizes the risk of unintended pregnancy and sexually transmitted diseases for youth. While there have been many studies of specific programs in clinical or quasi-experimental settings, there are very few evaluations of how state-level sex education policies affect the youth population. We estimate the impact of various state-level sex education policies on youth sexual activity and contraceptive use using data from four waves of the Youth Risk Behavior Surveillance System from 39 states. We found that states that require sexuality (sex and/or HIV/STD) education and contraceptive content or states that mandate education but leave the actual content up to local districts have lower rates of sexually active youth and higher rates of contraception use when youth are sexually active. States that require sexuality education and require abstinence content increase the rate at which youth are sexually active, and youth in those states are less likely to use hormonal birth control if they are sexually active. In conclusion, we found that state policies regarding sex and HIV/STD education had statistically significant effects that are meaningful in magnitude from a public health perspective.

  相似文献   
52.
The pathogenesis of dialysis related amyloidosis remains unresolveddespite the identification of ß2-microglobulin (ß2M)as the major protein constituent, as well as other proteinsbeing present in the deposits. Among the latter we have assessedthe serum concentrations of 2-macroglobulin (2M) both in thebaseline stage and during the haemodialysis (HD) procedure.We have also assessed the influence of the membrane on 2M kinetics. Fifteen HD patients with histologically proven dialysis-relatedamyloidosis (DRA group) and 15 HD patients clinically and radiologicallyconsidered dialysis-related amyloidosis free (control group)were included in the baseline study. Blood was sampled the daybefore the second dialysis of the week and 2M, ß2Mand 1, antitrypsin were determined along with the routine biologicalanalysis of these patients. Serum 2M was greater in dialysis-relatedamyloidosis than in control patients (t = 2.35; P<0.026).Serum ß2M was similar in both groups. The serum 2Mand ß2M correlated in patients with dialysis-relatedamyloidosis (r = 0.64; P<0.01), while no correlation wasfound in controls (r = 0.17; NS). Stepwise analysis taking thepresence of dialysis-related amyloidosis as the dependent variableretained the serum 2M concentration as the first variable inthe model (F = 4.4; partial r = 0.38; P<0.046). The sameproteins were determined in another group of seven patients,before and hourly during HD as well as 2 and 8 h after the endof HD during nine consecutive dialyses (3 cycles of 3 HD eachusing AN69 and cuprophane membranes in a crossover design).Serum 2M significantly increased from hour 3 and continued toincrease 2 hours post-HD (+11% and +9% with AN69 and cuprophanerespectively; P<0.001). Total proteins peaked at hour 4 (+4% and +3% P<0.01) and decreased after HD. Serum ß2Msignificantly decreased with AN69 HD ( – 29% P<0.001)and remained unchanged during cuprophane HD. In conclusion, significant increases in serum 2M are observedimmediately after and during the early post-dialysis periods,regardless of the membrane used. Further, serum 2M correlateswith ß2M only in patients with dialysis-related amyloidosis,and this variable was retained in the multivariate regressionanalysis to predict dialysis-related amyloidosis. Although thebaseline results require confirmation with larger studies, wepostulate that the present results are of relevance for dialysis-relatedamyloidosis pathogenesis since 2M, previously identified indialysis related amyloid deposits, is closely related to acute-phasereactant proteins, and interacts with the main infiltratingcells of the deposits (macrophages). 2M modifications couldrepresent a new manifestation of the inflammatory response tothe haemodialysis procedure.  相似文献   
53.
目的;探讨手术治疗胸椎结核的更好方法。方法;自1990年以来,对21例胸椎结核导致椎柱不稳的患者,应用病灶清除,哈氏棒内固定,椎间及椎板植骨的手术方法。本组平均33.2岁。胸7椎体6例,胸8椎体8例,胸10椎体7例,椎体压缩〈1/2椎体高度13例,〉1/2椎体高度8例,并不全瘫14例。手术中先行病灶清除,然后哈氏棒内固一,撑开后再次清除病灶,取肋骨和髂骨行椎间及椎板上植骨。术后化疗12~15月。结  相似文献   
54.
The search for alternatives to metered-dose inhalers has accelerated recently in a bid to find effective products that do not use chlorofluorocarbon (CFC) propellants. This paper reviews the factors to be considered in developing dry powder inhalers (DPIs), particularly the formulation, metering design and flow path in the device. The advantages and disadvantages of current DPIs are discussed and possible future approaches outlined.  相似文献   
55.
This is the first report of the association of spina bifida and eating disorders. Five patients were diagnosed rather late in the course of their illness. They all had been overweight premorbidly and had been urged to lose weight for years in order to improve their mobility. As they dieted, they experienced their weight loss as a source of power that could somehow compensate for their losses and neurologic limitations. They responded to a multidisciplinary intervention. Clinicians taking care of patients with spina bifida need to be cognizant that they may be at risk of developing an eating disorder. Such awareness should influence the quality of nutritional counseling (prevention aspect) and the clinical assessment of sudden weight loss (early intervention).  相似文献   
56.
A strong relationship exists between employee satisfaction and patients' perceptions of the quality of their care, measured in terms of their intent to return and to recommend the hospital to others. Employee dissatisfaction can negatively affect quality of care and have an adverse effect on patient loyalty and, thus hospital profitability. Therefore, health care marketers should regularly measure employee satisfaction as one way to monitor service quality. Health care marketers must work more closely with their human-resource departments to understand and influence employees' work environment and maintain a high level of job satisfaction. Marketers also should place an increased emphasis on both employee and patient perceptions of satisfaction when developing internal and external strategic marketing plans and formulating future research.  相似文献   
57.
Fever: the old and the new   总被引:2,自引:0,他引:2  
Early concepts of fever as a major feature of illness range from those of Hippocrates to those present in the Bible and have influenced cultural attitudes during several major European pandemics of both black plague and tuberculosis, the "white plague" of the early 19th century. Evolving ideas of thermoregulation and fever in the 19th century followed the first extensive use of the clinical thermometer by Wunderlich. Experimental studies on the pathogenesis of fever during the last 30 years suggest that fever and certain aspects of both immunoregulation and inflammation are produced by a single hormone, the monokine interleukin-1, which has presumably been selected by evolution to protect the host against infection.  相似文献   
58.
Our experience of 54 patients with end-stage renal failure, who were treated with intermittent peritoneal dialysis and compared with patients maintained by haemodialysis over the years 1972 to 1978, has been reviewed. All patients received peritoneal dialysis for more than six weeks. The total experience was 32.8 patient dialysis-years, 48% as home dialysis. Peritoneal dialysis was used as an interim procedure in 19 patients who were waiting for haemodialysis. However, in 35 patients (particularly in the very young and elderly, and in situations of poor social support), recurrent peritoneal dialysis was chosen as the definitive dialysis therapy. Dialysis was assessed as "adequate" in all, but two, patients. The major complication of peritoneal dialysis was peritonitis, although its over-all incidence of 1.31 episodes per patient dialysis-year was low. An attack of peritonitis occurred every nine months of patient exposure, though the incidence of bacterial peritonitis averaged only once every 26 months. Fifty per cent of patients never had an episode of peritonitis. Intermittent peritoneal dialysis was associated with greater morbidity and mortality than haemodialysis, perhaps due, in part, to the older age of the peritoneal dialysis group. Intermittent peritoneal dialysis is a valuable adjunct to haemodialysis and transplantation in the treatment of end-stage renal failure.  相似文献   
59.
The HLA class I antigen-processing machinery (APM) plays a crucial role in the generation of peptides from endogenously synthesized proteins and in their presentation to cytotoxic T lymphocytes. The potential role of defects of APM components in immune escape mechanisms used by malignant cells has prompted us to analyze their expression in renal cell carcinoma (RCC) lesions with special emphasis on TAP because of its critical role in the loading of HLA class I antigens with peptides. Immunohistochemical staining of 51 formalin-fixed RCC lesions and autologous normal renal epithelium detected transporter associated with antigen processing (TAP)1 and tapasin deficiencies in 63 and 80% of the tumor lesions. Impaired low molecular weight protein (LMP)2 and LMP7 expression was found in 73 and 33% of the RCC lesions analyzed, respectively. In contrast to the high frequency of APM component down-regulation, HLA class I heavy chain and beta(2)-microglobulin defects were detected in only 12 and 10% of the lesions, respectively. Concomitant TAP1 and LMP2 deficiencies were found in approximately 57% of RCC lesions, whereas a coordinated down-regulation of all APM components occurred only in 5% of the tumor specimens analyzed. The presence of APM defects was independent of tumor stage and grade but varied significantly among the RCC subtypes. TAP abnormalities do not appear to be attributable to structural alterations because no mutations in TAP1 were detected in TAP1-deficient RCC lesions. These data suggest that TAP defects in RCC lesions are caused by regulatory abnormalities. Therefore, T-cell-based immunotherapy may benefit from the administration of cytokines that up-regulate TAP expression.  相似文献   
60.
KA Daly  RE Selvius  B Lindgren 《Pediatrics》1997,100(6):931-936
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for 相似文献   
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