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121.
The nutritional pathways of intrasynovial tendons have been investigated by transplantation of a free tendon graft to the knee joint. These grafts developed adhesions to host tissues as early as 2 days after operation. Central necrosis was apparent after 1 week. By 3 weeks postoperation, metabolically active infiltrating cells from the synovial layer of the tendon removed necrotic material, and began the process of partial regeneration of the tendon. This was clearly apparent at 9 weeks. At this stage, the new tenocytes had assumed the metabolic pattern of normal adult tendon cells. It is concluded that the vascularised synovial layer of the tendon is of paramount importance in the remodeling process.  相似文献   
122.
OBJECTIVE: Recently, greater attention has been paid to the role of inflammatory processes in the pathophysiology of Alzheimer disease (AD). However, the mechanism by which anti-inflammatory agents (NSAIDs) might slow the progression of AD is not completely known. The aim of the present study was to examine the relationship between NSAIDs use and AD in a large sample of community-dwelling elderly people. METHODS: In a cross-sectional retrospective study, the authors analyzed data on patients admitted to home care programs. A total of 12 home health agencies participated in the project, with a total of 2,708 patients enrolled in the present study. The main outcome measures were the prevalence of AD and use of NSAIDs treatment. RESULTS: Compared with all non-users, NSAID users had a nearly 50% lower risk of being affected by AD. Separate multivariate analyses of subjects receiving different types of NSAIDs found a significantly decreased risk of cognitive impairment associated with non-aspirin NSAID use, whereas, among subjects taking aspirin, the difference in estimated risk did not reach statistical significance. CONCLUSION: The results of this population-based cross-sectional study are consistent with the notion that long-term NSAIDs use has a protective effect against AD. However, after possible confounding effects of age and several other variables potentially associated with cognitive impairment were controlled, this association was statistically significant only for non-aspirin NSAIDs use.  相似文献   
123.
OBJECTIVE: Ischemic mitral regurgitation (IMR) results from a variable combination of annular dilatation and remodeling of the subvalvular apparatus. Current surgical techniques effectively treat annular dilatation, but methods for addressing subvalvular remodeling have not been standardized. An effective technique for determining the extent of subvalvular remodeling could improve surgical results by identifying patients who are unlikely to benefit from annuloplasty alone. METHODS: A well-characterized ovine model of IMR was employed. Real-time three-dimensional echocardiography was performed on each animal at baseline, immediately after infarction and 8 weeks after infarction. Intercommissural width and mitral annular area were calculated for each subject at each time point. Mitral valve tenting area and height were calculated at discrete intervals along the entire intercommissural axis. The location at which maximal tenting area and height occurred was recorded. Mitral valve tenting volume was calculated by summation. RESULTS: Both immediate and long-term increases were observed in mean intercommissural width and mean mitral annular area (from 33.2 to 36.3 to 39.7 mm and from 740 to 810 to 1020 mm(2), respectively). Both immediate and long-term increases were observed in maximum mitral valve tenting area and height (from 38.5 to 50.6 to 112.1mm(2) and from 3.9 to 4.7 to 10.1mm, respectively). Mitral valve tenting area and height at the mid-point of the intercommissural axis did not change significantly during the observation period. The position along the intercommissural axis at which maximal mitral valve tenting area and height occurred shifted progressively toward the anterior commissure (from 51.8% to 45.1% to 38.9% and from 52.9% to 45.1% to 37.8%). Both immediate and long-term increases were observed in mitral valve tenting volume (from 474.0 to 622.1 to 1483.5mm(3)). CONCLUSIONS: We have described a technique that utilizes real-time three-dimensional echocardiography to perform a comprehensive assessment of leaflet tethering on the entire mitral valve. Our methodology is not influenced by viewing plane selection, regional tenting asymmetry, or annular dilatation and, therefore, represents a potentially useful surrogate measure of subvalvular remodeling.  相似文献   
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The cervico-cranial arteries were studied using digital subtraction angiography in 50 patients with reversible cerebral ischaemic attacks and normal continuous wave Doppler examination. Digital subtraction angiography was able to visualise the arteries satisfactorily in 45 patients (90%), and revealed minor arterial abnormalities in 12 patients (24%). However, neither occlusions nor stenoses greater than 50% of the diameter of the vessel lumen were found. Although digital subtraction angiography is more accurate than continuous wave Doppler examination in detecting arterial lesions, it did not provide alternative therapeutic choices in any of these patients.  相似文献   
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Insulin-like growth factor I (IGF-I) stimulates cell proliferation and can enhance the development of tumours in different organs. Epidemiological studies have shown that an elevated level of circulating IGF-I is associated with increased risk of breast cancer, as well as of other cancers. Most of circulating IGF-I is bound to an acid-labile subunit and to one of six insulin-like growth factor binding proteins (IGFBPs), among which the most important are IGFBP-3 and IGFBP-1. Polymorphisms of the IGF1 gene and of genes encoding for the major IGF-I carriers may predict circulating levels of IGF-I and have an impact on cancer risk. We tested this hypothesis with a case-control study of 807 breast cancer patients and 1588 matched control subjects, nested within the European Prospective Investigation into Cancer and Nutrition. We genotyped 23 common single nucleotide polymorphisms in IGF1, IGFBP1, IGFBP3 and IGFALS, and measured serum levels of IGF-I and IGFBP-3 in samples of cases and controls. We found a weak but significant association of polymorphisms at the 5' end of the IGF1 gene with breast cancer risk, particularly among women younger than 55 years, and a strong association of polymorphisms located in the 5' end of IGFBP3 with circulating levels of IGFBP-3, which confirms previous findings. Common genetic variation in these candidate genes does not play a major role in altering breast cancer risk in Caucasians.  相似文献   
129.
GenoMEL, comprising major familial melanoma research groups from North America, Europe, Asia, and Australia has created the largest familial melanoma sample yet available to characterize mutations in the high-risk melanoma susceptibility genes CDKN2A/alternate reading frames (ARF), which encodes p16 and p14ARF, and CDK4 and to evaluate their relationship with pancreatic cancer (PC), neural system tumors (NST), and uveal melanoma (UM). This study included 466 families (2,137 patients) with at least three melanoma patients from 17 GenoMEL centers. Overall, 41% (n = 190) of families had mutations; most involved p16 (n = 178). Mutations in CDK4 (n = 5) and ARF (n = 7) occurred at similar frequencies (2-3%). There were striking differences in mutations across geographic locales. The proportion of families with the most frequent founder mutation(s) of each locale differed significantly across the seven regions (P = 0.0009). Single founder CDKN2A mutations were predominant in Sweden (p.R112_L113insR, 92% of family's mutations) and the Netherlands (c.225_243del19, 90% of family's mutations). France, Spain, and Italy had the same most frequent mutation (p.G101W). Similarly, Australia and United Kingdom had the same most common mutations (p.M53I, c.IVS2-105A>G, p.R24P, and p.L32P). As reported previously, there was a strong association between PC and CDKN2A mutations (P < 0.0001). This relationship differed by mutation. In contrast, there was little evidence for an association between CDKN2A mutations and NST (P = 0.52) or UM (P = 0.25). There was a marginally significant association between NST and ARF (P = 0.05). However, this particular evaluation had low power and requires confirmation. This GenoMEL study provides the most extensive characterization of mutations in high-risk melanoma susceptibility genes in families with three or more melanoma patients yet available.  相似文献   
130.
The authors describe the unique case of a patient who had undergone posterior stabilization of the lumbar spine complicating the course of a lymphatic fistula. A lymphatic fistula is a rare complication of posterior lumbar surgery. Predisposing factors include individual anatomy, scarring adherences due to previous abdominal operations or surgical maneuvers deep in the plane of the transverse processes. Because the onset of lymphatic fistulas is subtle, and because they are associated with a high mortality rate and require multidisciplinary treatment, care is needed to avoid misdiagnosing these lesions as the more common cerebrospinal fluid fistula.  相似文献   
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