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51.
Hip fractures are the most devastating consequence of osteoporosis and impact 1 in 6 white women leading to a two‐ to threefold increased mortality risk in the first year. Despite evidence of inflammatory markers in the pathogenesis of osteoporosis, few studies have examined their effect on hip fracture. To determine if high levels of inflammation increase hip fracture risk and to explore mediation pathways, a case‐cohort design nested in a cohort of 4709 white women from the Study of Osteoporotic Fractures was used. A random sample of 1171 women was selected as the subcohort (mean age 80.1 ± 4.2 years) plus the first 300 women with incident hip fracture. Inflammatory markers interleukin‐6 (IL‐6) and soluble receptors (SR) for IL‐6 (IL‐6 SR) and tumor necrosis factor (TNF SR1 and TNF SR2) were measured, and participants were followed for a median (interquartile range) of 6.3 (3.7, 6.9) years. In multivariable models, the hazard ratio (HR) of hip fracture for women in the highest inflammatory marker level (quartile 4) was 1.64 (95% confidence interval [CI], 1.09–2.48, p trend = 0.03) for IL‐6 and 2.05 (95% CI, 1.35–3.12, p trend <0.01) for TNF SR1 when compared with women in the lowest level (quartile 1). Among women with 2 and 3–4 inflammatory markers in the highest quartile, the HR of hip fracture was 1.51 (95% CI, 1.07–2.14) and 1.42 (95% CI, 0.87–2.31) compared with women with zero to one marker(s) in the highest quartile (p trend = 0.03). After individually adjusting for seven potential mediators, cystatin‐C (a biomarker of renal function) and bone mineral density (BMD) attenuated HRs among women with the highest inflammatory burden by 64% and 50%, respectively, suggesting a potential mediating role. Older white women with high inflammatory burden are at increased risk of hip fracture in part due to poor renal function and low BMD. © 2014 American Society for Bone and Mineral Research.  相似文献   
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This study examined the predictors of dieting, extreme weight loss behaviors, and binge eating in adolescents (606 females and 315 males). High school classes were administered measures of weight loss behaviors, binge eating, perceived current and ideal body size, body dissatisfaction, advantages of being thinner and physically fitter, satisfaction with fitness, depression, self-esteem, parental overprotection, parental caring, and family adaptability and cohesion. Principal component analyses grouped predictor (body image, psychosocial) and criterion (weight loss behaviors, binge eating) variables. The primary predictor of weight loss behaviors in both sexes and binge eating in girls was the desire to be thinner which included a larger current body size. Psychological and family variables played lesser roles but were significantly predictive in a number of cases. Sex differences in factor structures and important predictors emerged. © 1992 John Wiley & Sons, Inc.  相似文献   
55.
Blood gas analysis: a study of blood loss in intensive care   总被引:3,自引:0,他引:3  
This paper describes a quantitative study conducted on an intensive care unit in the north of England. It involved the collection of data from the existing records of 65 patients consecutively sampled from a predetermined date provided that they stayed more than 24 hours and had an arterial line in situ. As patient records were used, ethical approval was not necessary. The objectives of the study were to quantify the mean number of blood gas samples taken per patient and estimate the mean blood loss resulting from this, including discard volume. Limitations include reliance on records and lack of an economic evaluation. The results show that blood loss in this study was greater than that reported elsewhere. Patients who were ventilated for 24 hours or more had a statistically significant greater blood loss when compared to those who were not (P < 0.001). A subgroup of patients undergoing renal replacement therapy had the greatest blood loss (mean 55.18 ml per day). This loss was statistically significant when compared to patients not in acute renal failure (P=0.007). When patients undergoing multiple therapies normally associated with increased sampling were compared to patients not receiving such therapies, there was no statistically significant difference in blood loss. The need to change current nursing practice to reduce iatrogenic anaemia is emphasized.  相似文献   
56.
目的:分析血管紧张素原基因启动子区A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压的相关性。方法:实验于2005-08/2006-01在北京华大实验室完成。选取对象均为生活在内蒙古乌拉特后旗的蒙古族牧民,三代血亲内无其他民族。采用基因测序技术对内蒙古蒙古族人群中107例原发性高血压患者和108例正常对照者进行A-20C和A-6G基因分型,观察高血压组和正常对照组不同基因型的分布和等位基因频率的差异。结果:①两组受试者在性别、年龄及吸烟、饮酒、体质量指数和临床化验检查指标有较好的匹配(P均>0.05)。②两组血管紧张素原基因A-20C位点AA,AC,CC基因型频率比较差异无显著性意义(高血压组分别为0.51,0.29,0.20;正常对照组分别为0.49,0.28,0.23,χ2=0.395,P=0.529)。A,C等位基因频率比较差异无显著性意义(高血压组分别为0.65,0.35;正常对照组分别为0.63,0.37,χ2=0.015,P=0.904)。③两组血管紧张素原基因A-6G位点AA,AG,GG基因型频率比较差异无显著性意义(高血压组分别为0.50,0.33,0.17;正常对照组分别为0.55,0.34,0.11,χ2=1.924,P=0.165)。A,G等位基因频率比较差异无显著性意义(高血压组分别为0.66,0.34;正常对照组分别为0.72,0.28,χ2=1.728,P=0.189)。④高血压组协同存在血管紧张素原基因A-20C基因型CC时,血管紧张素原基因A-6G基因型GG频率稍高于正常对照组,但差异无显著性意义(χ2=2.395,P=0.122,OR=7.52,95%CI0.014~1.250),高血压组G等位基因明显高于正常对照组(分别为0.37,0.22,χ2=4.658,P=0.034),携带该等位基因的蒙古族人群发生原发性高血压的相对危险度升高(OR=2.80,95%CI1.087~7.271)。结论:血管紧张素原基因A-20C和A-6G单核苷酸多态性与蒙古族人群原发性高血压相关,并可能具有协同作用。  相似文献   
57.
Association between elevated neutrophil defensin levels and endometritis   总被引:4,自引:0,他引:4  
The role of host defenses in the pathogenesis of pelvic inflammatory disease (PID) remains largely uncharacterized. The antimicrobial peptides defensins are important components of innate host defense. To explore the relationship between neutrophil defensins and upper genital tract infection, 377 women who were at risk for PID were enrolled in a study. Women infected with Neisseria gonorrhoeae, Trichomonas vaginalis, or Chlamydia trachomatis had higher median levels of neutrophil defensins (human neutrophil peptides 1-3) in the vagina than did uninfected women. Neutrophil defensins were strongly associated with the presence of endometritis after the analysis was controlled for the presence of sexually transmitted diseases. Vaginal neutrophils were associated with endometritis only in the presence of elevated defensin levels, which highlights the importance of neutrophil activation, rather than the presence of neutrophils alone, in this inflammatory process. Neutrophil defensins appear to participate in the host defense in ascending pelvic infection and the pathogenesis of PID.  相似文献   
58.
Effective interventions to prevent obesity in children have never been more necessary. There have been over 30 published reviews and meta-analyses on such interventions (randomized and controlled trials) since 2008. In summary, interventions which involve the whole community (community-based) in complex interventions (promoting healthy eating, reduction in sedentary behaviours and increase in physical activity) that target environments and upstream determinants appear to be more effective. In this article the strengths and weaknesses of community-based complex interventions which aim to prevent obesity in children will be discussed and a selection of recent and ongoing interventions that are shaping the evidence-base in this field will be highlighted (beyond those reported in other papers in this supplement: KOPS, CHILT, TigerKids, IDEFICS and TrinkFit). This paper reviews the challenges and opportunities associated with designing and evaluating community-based complex interventions and initiatives. These include a) design issues (strengths and weaknesses of different types of evidence), b) measurement of (effectiveness) outcomes, c) development of interventions (pilot work, planning frameworks and underpinning theories), d) partnership working and community engagement and e) health inequalities.  相似文献   
59.
Predictors of glycemic control in insulin-using adults with type 2 diabetes   总被引:3,自引:0,他引:3  
OBJECTIVE: To determine the characteristics that influence glycemic control among insulin-using adults with type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied all 1,333 eligible members of a large not-for-profit health maintenance organization who responded to a 1997 survey. We tested associations among demographic, treatment, and psychometric variables with mean 1997 HbA1c values. The Problem Areas in Diabetes (PAID) instrument was used to assess the emotional effect of living with diabetes, and the Short Form 12 Physical Function Scale was used to assess the effect of physical limitations on daily activities. Based on differences between and within treatment groups, we built models to predict glycemic control for subgroups of subjects who were using insulin alone and those who were using insulin in combination with an oral hypoglycemic agent. RESULTS: Younger age, lower BMI, and increased emotional distress about diabetes (according to the PAID scale) were all significant predictors (P < 0.05) of worse glycemic control. However, except among individuals with an HbA1c level of >8.0 who were receiving combination therapy, only approximately 10% of the variance in glycemic control could be predicted by demographic, treatment, or psychometric characteristics. CONCLUSIONS: Personal characteristics explain little of the variation in glycemic control in insulin-using adults with type 2 diabetes. Possible explanations are that the reduced complexity of control in type 2 diabetes makes the disease less sensitive to personal factors than control in type 1 diabetes, that health-related behavior is less driven by personal and environmental characteristics among older individuals, or that, in populations exposed to aggressive glycemic control with oral hypoglycemic agents and nurse care managers, personal differences become largely irrelevant.  相似文献   
60.
The introduction of antibiotic prophylaxis for cesarean delivery has decreased the risk of postpartum endometritis and wound infection, but factors that contribute to prophylaxis failure are not understood. To determine factors that might contribute to postpartum infections following antibiotic prophylaxis, we cultured amniotic fluid, decidua, and chorioamniotic membrane specimens for anaerobic and facultative bacteria and for genital mycoplasmas at cesarean delivery. Women were assessed daily for the development of infections, and if endometritis developed, a protected endometrial culture was obtained. Postpartum endometritis developed in 16 and wound infection in four of 102 women. Infection rates were similar for women receiving cefotetan (N = 50) or cefoxitin (N = 52) for prophylaxis. The isolation of group B streptococcus (P less than .001) or Enterococcus faecalis (P = .03) from the upper genital tract at delivery was significantly associated with postpartum endometritis. Antibiotic-resistant organisms (other than enterococci) were recovered uncommonly at delivery or with postpartum infections. Group B streptococcus was susceptible to the prophylactic agents used, suggesting that virulence factors other than antibiotic resistance are important for the development of postpartum endometritis. Group B streptococcus, E faecalis, and bacteria associated with bacterial vaginosis were recovered from the endometrium at the time of postpartum endometritis.  相似文献   
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