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91.
Selected health status data for elderly populations from similar industrial cities-Youngstown, Ohio, USA, and Debrecen, Hungary—were compared. Because of their impoverished health care system, unregulated heavily industrialized society, and unhealthful life-styles Hungarians were hypothesized to have poorer health status than Americans, even after taking into account demographic mediating factors. The study provides a health status baseline for elderly Hungarians shortly after communism's fall in 1989–1990 and shows how great a gap exists between Hungarian health status and that in the West. Hungarians were in much poorer health as measured by functional status, symptomatology, medical condition, depression, and subjective health status. Distinctions persisted when controlling for gender, age, and education. Poverty-level (and income) did not explain health status differences. The paper concludes that Hungary should pay more attention to health promotion, prevention, and primary care, as well as to reforming patient management in hospitals, nursing homes, and home care programs.  相似文献   
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Psychosocial assets of 37 adults with cystic fibrosis (CF) and 46 of their healthy peers were assessed by mailed questionnaire. Major sociodemographic variables did not differ significantly between the two groups, nor did indices of emotional social support, social network density, self-esteem, or current life satisfaction. This study revealed adults with CF to function on a par with their healthy peers in nearly all respects, a finding at odds with those from uncontrolled studies and which suggests to us that many previous conclusions about the psychosocial health of adults with CF have been unwarranted. Future psychosocial studies involving patients with CF should include control groups and inferences about the effect of these patients' physical illness on their psychosocial health should not be made in the absence of normative data.  相似文献   
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Idiopathic osteoporosis (IOP) in premenopausal women is characterized by fragility fractures at low or normal bone mineral density (BMD) in otherwise healthy women with normal gonadal function. Histomorphometric analysis of transiliac bone biopsy samples has revealed microarchitectural deterioration of cancellous bone and thinner cortices. To examine bone material quality, we measured the bone mineralization density distribution (BMDD) in biopsy samples by quantitative backscattered electron imaging (qBEI), and mineral/matrix ratio, mineral crystallinity/maturity, relative proteoglycan content, and collagen cross‐link ratio at actively bone forming trabecular surfaces by Raman microspectroscopy and Fourier transform infrared microspectroscopy (FTIRM) techniques. The study groups included: premenopausal women with idiopathic fractures (IOP, n = 45), or idiopathic low BMD (Z‐score ≤ ?2.0 at spine and/or hip) but no fractures (ILBMD, n = 19), and healthy controls (CONTROL, n = 38). BMDD of cancellous bone showed slightly lower mineral content in IOP (both the average degree of mineralization of cancellous bone [Cn.CaMean] and mode calcium concentration [Cn.CaPeak] are 1.4% lower) and in ILBMD (both are 1.6% lower, p < 0.05) versus CONTROL, but no difference between IOP and ILBMD. Similar differences were found when affected groups were combined versus CONTROL. The differences remained significant after adjustment for cancellous mineralizing surface (MS/BS), suggesting that the reduced mineralization of bone matrix cannot be completely accounted for by differences in bone turnover. Raman microspectroscopy and FTIRM analysis at forming bone surfaces showed no differences between combined IOP/ILBMD groups versus CONTROL, with the exceptions of increased proteoglycan content per mineral content and increased collagen cross‐link ratio. When the two affected subgroups were considered individually, mineral/matrix ratio and collagen cross‐link ratio were higher in IOP than ILBMD. In conclusion, our findings suggest that bone material properties differ between premenopausal women with IOP/ILBMD and normal controls. In particular, the altered collagen properties at sites of active bone formation support the hypothesis that affected women have osteoblast dysfunction that may play a role in bone fragility. © 2012 American Society for Bone and Mineral Research.  相似文献   
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Bone morphogenetic proteins (BMP) have to be applied at high concentrations to stimulate bone healing. The limited therapeutic efficacy may be due to the local presence of BMP antagonists such as Noggin. Thus, inhibiting BMP antagonists is an attractive therapeutic option. We hypothesized that the engineered BMP2 variant L51P stimulates osteoinduction by antagonizing Noggin-mediated inhibition of BMP2. Primary murine osteoblasts (OB) were treated with L51P, BMP2, and Noggin. OB proliferation and differentiation were quantified with XTT and alkaline phosphatase (ALP) assays. BMP receptor dependent intracellular signaling in OB was evaluated with Smad and p38 MAPK phosphorylation assays. BMP2, Noggin, BMP receptor Ia/Ib/II, osteocalcin, and ALP mRNA expressions were analyzed with real-time PCR. L51P stimulated OB differentiation by blocking Noggin mediated inhibition of BMP2. L51P did not induce OB differentiation directly and did not activate BMP receptor dependent intracellular signaling via the Smad pathway. Treatment of OB cultures with BMP2 but not with L51P resulted in an increased expression of ALP, BMP2, and Noggin mRNA. By inhibiting the BMP antagonist Noggin, L51P enhances BMP2 activity and stimulates osteoinduction without exhibiting direct osteoinductive function. Indirect osteoinduction with L51P seems to be advantageous to osteoinduction with BMP2 as BMP2 stimulates the expression of Noggin thereby self-limiting its own osteoinductive activity. Treatment with L51P is the first protein-based approach available to augment BMP2 induced bone regeneration through inhibition of BMP antagonists. The described strategy may help to decrease the amounts of exogenous BMPs currently required to stimulate bone healing.  相似文献   
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On the chest X-ray of a 15-year-old patient, a round, egg-shell-like calcification was seen in projection into the left heart border. This finding was caused by a calcified coronary aneurysm following Kawasaki's disease. Although this has been described as a typical change, it is rarely found in daily clinical routine.  相似文献   
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林亚平  卢维伦 《药学学报》1997,32(11):869-873
基于以下两点事实:Fick第一扩散定律中的扩散系数并非严格的常数,它随浓度变化;Fick第一扩散定律只适用于浓度梯度恒定的稳定扩散,而许多实验表明浓度梯度也是一个时间函数,本文对Fick第一扩散定律作出两点修正将原定律中浓度梯度和扩散系数分别修正为时间函数和浓度函数,从而导出关于非溶蚀型药物体系的释放动力学模型。该模型较其他常用释放模型有更好的拟合效果,其参数也有较为明确的物理意义。  相似文献   
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