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91.
A total of 61 patients with a proximal humeral fracture was treated between January 1996 and March 1998 by closed reduction and fracture fixation with intramedullary Prévot (or Nancy) nails. Of these, 28 female and 25 male patients with a mean age of 52 years (range 3-91 years) were reviewed clinically and radiologically with a mean follow-up of 17 months (range 4-30 months). The mean Constant score was 63, the mean Neer score 74 and the mean visual analogue scale (VAS) 73. The 14 patients under 24 years old achieved a Constant score of 86, a Neer score of 99 and a VAS of 97, while 13 patients aged between 25 and 60 years had a Constant score of 67, a Neer score of 75 and a VAS of 71. The 26 patients older than 61 years had a Constant score of 48, a Neer score of 61 and a VAS of 61. One patient with total and 6 with partial humeral head necrosis as well as 5 pseudarthroses were noted. Proximal nail perforation of the humeral head due to fracture collapse was seen in 22 cases. Complications were more frequently observed in the elderly. End results were not related to the type of fracture. This minimally invasive technique decreases the rate of occurrence of avascular necrosis of the humeral head. However, fractures are not sufficiently stabilised, mainly because of bone loss induced by impaction and osteoporosis. Bone loss remains an unsolved problem, and alternative methods such as the use of bone substitute combined with minimally invasive techniques should be studied.  相似文献   
92.
Semicarbazide-sensitive amine oxidase (SSAO) is highly expressed in adipose cells, and substrates of SSAO, such as benzylamine, in combination with low concentrations of vanadate strongly stimulate glucose transport and GLUT4 recruitment in 3T3-L1 and rat adipocytes. Here we examined whether acute and chronic administration of benzylamine and vanadate in vivo enhances glucose tolerance and reduces hyperglycemia in diabetic rats. Acute intravenous administration of these drugs enhanced glucose tolerance in nondiabetic rats and in streptozotocin (STZ)-induced diabetic rats. This occurred in the absence of changes in plasma insulin concentrations. However, the administration of benzylamine or vanadate alone did not improve glucose tolerance. The improvement caused by benzylamine plus vanadate was abolished when rats were pretreated with the SSAO-inhibitor semicarbazide. Chronic administration of benzylamine and vanadate exerted potent antidiabetic effects in STZ-induced diabetic rats. Although daily administration of vanadate alone (50 and 25 micromol x kg(-1) x day(-1) i.p.) for 2 weeks had little or no effect on glycemia, vanadate plus benzylamine reduced hyperglycemia in diabetic rats, enhanced basal and insulin-stimulated glucose transport, and upregulated GLUT4 expression in isolated adipocytes. In all, our results substantiated that acute and chronic administration of benzylamine with low dosages of vanadate have potent antidiabetic effects in rats.  相似文献   
93.
The metabolic syndrome is a complex condition characterized by dyslipidaemia, high blood pressure, impaired glucose tolerance and abdominal fat accumulation. Subjects with the metabolic syndrome are at high risk of atherosclerosis and coronary heart disease. A comprehensive approach is required for patients suffering this cluster of clinical manifestations. Indeed, subjects with the metabolic syndrome could benefit from life-style modifications, particularly through exercise and diet. In this article, the evidence regarding the role of diet, in particular the role of food patterns based on the Mediterranean-style diet, in preventing and treating the metabolic syndrome are reviewed.  相似文献   
94.
Obesity, which is becoming one of the major health hazards in developed and developing societies, results from a long-term positive energy balance. Body-weight regulation and stability depend on an axis with three interrelated components: food intake, energy expenditure and adipogenesis, although there are still many unknown features concerning fuel homeostasis and energy balance. Biochemical processes are interconnected, and a separate consideration of each component is often useful for methodological purposes and to achieve a better understanding of the whole system. Thus, many different experimental approaches can be applied by using laboratory animals, cell culture or human subjects to unravel the molecular mechanisms which participate in body-weight regulation. Thus, both in vitro (cellular and subcellular models) and in vivo methods have dramatically increased our knowledge of weight control. Several strategies in obesity research are reported here, exploiting the opportunities of the molecular era as well as novel whole-body approaches, which will impact on the development of new targets for obesity management and prevention.  相似文献   
95.
96.
In a large, community-based cardiovascular disease prevention study in Eastern Finland, independent random population samples were surveyed in 1972, 1977 and 1982. The leisure-time physical activity (LTPA), occupational physical activity (OPA), and socioeconomic and lifestyle characteristics were assessed. In men and women aged 30-59, the proportion with high LTPA increased from 1972 to 1982 by approximately one half (p less than 0.001), whereas that of high OPA decreased during the same period (p less than 0.001). In both sexes, high overall physical activity fell from 1972 to 1977 (p less than 0.001), but no more from 1977 to 1982. The proportion of entirely sedentary remained stable. Education, income and younger age showed a positive, body mass index, smoking and OPA a graded, negative association with high LTPA in 1972 and 1982. Significant (p less than 0.001) differences in 10-year trends of changes in LTPA were observed: men and women with low education or income increased LTPA more than those with high education and income. Socioeconomic factors, such as income and education, appear to have lost importance as determinants of population-wide exercise, whereas the clustering of low physical activity with overweight and smoking has increased.  相似文献   
97.
Although cancer is a leading cause of morbidity and premature death among Latinos, there is limited knowledge of cancer-related issues and priorities of greatest significance to the Latino population, the largest minority group in the nation. This information is vital in helping to guide Latino cancer research, training, and awareness efforts at national, regional, and local levels. To help identify cancer issues of greatest relevance to Latinos, Redes En Accion, The National Hispanic/Latino Cancer Network, a major network among the National Cancer Institute's Special Populations Networks, conducted a survey of 624 key opinion leaders from around the country. Respondents were asked to rank the three cancer sites most important to Latinos in their region and the five issues of greatest significance for this population's cancer prevention and control. Recommendations were prioritized for three specific areas: 1) research, 2) training and/or professional education, and 3) awareness and/or public education. Among cancers, breast carcinoma was ranked number one, followed in order by cervical and lung carcinomas. The issues of greatest significance to Latinos were 1) access to cancer screening and care, 2) tobacco use, 3) patient-doctor communication, 4) nutrition, and 5) risk communication. This survey solicited information from scientists, health care professionals, leaders of government agencies, professional and community-based organizations, and other stakeholders in Latino health. The results laid the foundation for a national Redes En Accion Latino cancer agenda, thus providing a useful tool for individuals and organizations engaged in cancer prevention and control efforts among the Hispanic-Latino population.  相似文献   
98.
BACKGROUND: The mechanisms leading to aseptic loosening of a total hip replacement are not fully understood. A fibrous tissue interface can be present around the implant. Hypothetically, component micromovements can compress this interface and cause increased fluid pressure according to biphasic models. We tested the hypothesis that compression of a fibrous membrane with or without the presence of high-density polyethylene particles leads to bone degradation. METHODS: A titanium implant was inserted in forty-five rabbit tibiae, and, after osseous integration was achieved, a fibrous tissue interface was generated. The animals were randomized to undergo a sham operation, treatment with compression of the fibrous membrane, treatment with high-density polyethylene particles, or treatment with both compression and particles. Morphometric analysis of the surrounding bone was performed on cryostat sections after Giemsa staining and staining of tartrate-resistant acid phosphatase activity. RESULTS: Forty specimens were available for analysis; five tibiae with an infection were excluded. After nine weeks, the controls showed vital bone, whereas the specimens treated with compression showed necrosis of bone and replacement of bone by cartilage in a discontinuous layer (p < 0.05 for both) but not fibrous tissue. Treatment with high-density polyethylene particles caused replacement of bone by fibrous tissue (p < 0.05) but not necrosis or cartilage formation. Compression combined with the presence of high-density polyethylene particles caused bone necrosis and loss of bone with replacement by cartilage and fibrous tissue (p < 0.05). CONCLUSIONS: In this in vivo study in rabbits, fibrous membrane compression led to bone necrosis and cartilage formation, possibly because of fluid pressure or fluid flow, whereas the presence of high-density polyethylene particles led to the loss of bone with replacement of bone by fibrous tissue. Cartilage formation may be a protective response to fluid pressure and/or fluid flow. Fibrous membrane compression may play an important role in the early stages of loosening of a total hip replacement.  相似文献   
99.
Intertrochanteric osteotomy may postpone the need for total hip replacement (THR). In young patients with an acquired deformity of the femoral head and secondary osteoarthritis, a valgus intertrochanteric osteotomy may allow better congruency but the acetabular cover may become insufficient because of subluxation of the femoral head. In patients with a spherical femoral head and acetabular dysplasia, cover can still remain insufficient after varus displacement osteotomy. We present the long-term results of intertrochanteric osteotomy combined with an acetabular shelfplasty in both these circumstances. Sixteen hips (15 patients) with a deformed femoral head, and ten (seven patients) with a spherical femoral head, underwent an intertrochanteric osteotomy and acetabular shelfplasty. The mean age at the time of surgery was 30 and 37 years and the mean final follow-up was 15 and 19 years, respectively. Six patients in the deformed group, but only one in the spherical group, had required a THR by the time of their final follow-up. In both groups, those who had not undergone a THR had a good result. Acetabular shelfplasty is an excellent addition to an intertrochanteric osteotomy and gives full cover of the femoral head in patients with a deformity of the head and secondary osteoarthritis.  相似文献   
100.
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