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1.
Stability of transverse expansion in the mandibular arch.   总被引:1,自引:0,他引:1  
This was a retrospective, longitudinal cephalometric and cast study of 29 white patients at pretreatment, posttreatment, and an average of 6 years 3 months postretention. The goal was to assess changes with treatment and retention with the expanding mandibular lingual arch appliance in conjunction with fixed edgewise treatment. Seven mandibular cast measurements were assessed, including arch crowding, arch perimeter, arch length, and arch width at the permanent canines, first premolars, second premolars, and first molars. Cephalometric radiographs were digitized, and 16 cephalometric measurements were made. Repeated-measures analysis of variance and 2-sample t tests were used to determine statistically significant changes. It was found that the expanding lingual arch used for less than 6 months with the mandibular fixed edgewise appliance caused an increase in both the transverse and sagittal dimensions of the mandibular dental arch. Transverse expansion was more stable in the posterior region of the mandibular dental arch than in the anterior region. Mandibular intercanine width increase could be maintained only by fixed retention. Although the maxillary and mandibular incisors were advanced and proclined, lip protrusion did not occur.  相似文献   
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The electromyographic (EMG) interference pattern (IP) was measured in the biceps muscle of 16 normal male and 17 normal female subjects. The activity, upper centile amplitude (UCA), and the number of small segments (NSS) (defined in a companion paper) were measured from 500-msec epochs of the IP. The normal values of these features were defined separately for men and women by plotting the UCA and NSS values against activity for each epoch and defining an area on these plots, called a “cloud,” that contained more than 90% of the datum points from each study. The mean deviation of the individual datum points from the overall mean values was also calculated for each study. A study in one muscle is considered to be normal if more than 90% of the datum points from that muscle are within the normal clouds and the deviation values are within their normal range. In patients with neuropathy, the characteristic pattern was increased UCA with normal or decreased NSS. In patients with myopathy, NSS was increased and the UCA was normal or decreased. In all studies, the interpretations of the IP from the plots agreed with qualitative assessments of the IP made independently by an electromyographer. The use of these features to understand and quantitate the changes in the motor units produced by disease is demonstrated by serial studies performed in a patient with motor neuron disease.  相似文献   
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The ability to identify, isolate, and transplant progenitor cells from solid tissues would greatly facilitate the treatment of diseases currently requiring whole organ transplantation. In this study, cell fractions enriched in candidate epithelial progenitor cells from the rat pancreas were isolated and transplanted into the liver of an inbred strain of Fischer rats. Using a dipeptidyl dipeptidase IV genetic marker system to follow the fate of transplanted cells in conjunction with albumin gene expression, we provide conclusive evidence that, after transplantation to the liver, epithelial progenitor cells from the pancreas differentiate into hepatocytes, express liver-specific proteins, and become fully integrated into the liver parenchymal structure. These studies demonstrate the presence of multipotent progenitor cells in the adult pancreas and establish a role for the liver microenvironment in the terminal differentiation of epithelial cells of foregut origin. They further suggest that such progenitor cells might be useful in studies of organ repopulation following acute or chronic liver injury.  相似文献   
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Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. INTRODUCTION: Since FDA approval of PTH [PTH(1-34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. MATERIALS AND METHODS: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 microg/kg PTH(1-34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. RESULTS: Quantitative muCT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized beta-catenin protein, a central feature of canonical Wnt signaling. CONCLUSIONS: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways.  相似文献   
6.
Role of Embolisation in preoperative management of Nasopharyngeal angiofibroma is well established in present day therapeutic modalities. An improvised technique i.e., subselective embolisation has been provided by Interventional radiologists to fortify the therapeutic results. This study compares the final outcome of seven cases, four of which were embolised pre operatively. Each case was dealt with varying surgical approaches.  相似文献   
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Summary: This study compares the outcomes of 229 renal transplants, of which 156 were live related renal transplants done at our centre and 73 unrelated transplants done at other centres but followed up at our centre. All the patients were on triple immunosuppression for periods varying between 9 months and 1 year. Patient characteristics, rejections, infections and 1 and 5 years patient and graft survival were analyzed in the two groups. the outcome of patients who continued on cyclosporine beyond 1 year was compared to those who discontinued cyclosporine at 1 year. Males predominated (191 vs 38) in both groups, while younger patients (<50 years) predominated in live related group (152 vs four). There was no difference in the incidence of infection, rejection, graft dysfunction, graft loss or death between the two groups. the 1 and 5 year patient survival in the related and unrelated group, (93.7% and 71.4% vs and 85% and 66%) and graft survival (90.4% and 69.4% vs 83.3% and 65.4%) were similar. However, in the unrelated group, patients who discontinued cyclosporine had a higher incidence of rejections (38% vs 14%) and graft loss (43% vs 11.8%), while in the related group no such difference was found. It is concluded that 1 and 5 year patient and graft survival is comparable between live related and live unrelated transplantation. However, in the unrelated group it is necessary to continue cyclosporine beyond 1 year in order to achieve comparable results.  相似文献   
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Endoscopic sclerotherapy in the treatment of gastric varices   总被引:4,自引:0,他引:4  
Of 309 patients with portal hypertension, gastric varices were found in 48 (16 per cent). While the majority (88 per cent) of the patients had gastric varices in association with oesophageal varices, 6 (12 per cent) patients had 'isolated' gastric varices. Gastric varices were seen significantly (P less than 0.01) more often with grade 4 than with grade 3 varices. In 11 (28 per cent) of the 40 patients who completed sclerotherapy for oesophageal varices, gastric varices disappeared concurrently on eradication of oesophageal varices or during the following 6 months. Of the initial five patients with gastric varices who received direct intravariceal injections, four rebled; this technique was therefore replaced by combination (paravariceal + intravariceal) gastric variceal sclerotherapy. Emergency combination sclerotherapy successfully controlled bleeding from gastric varices in six of the eight treated patients. Thirty-two patients entered a programme of elective combination gastric variceal sclerotherapy. Variceal obliteration was achieved in 12 cases (38 per cent) and reduction in size was noted in another 7 patients (22 per cent) after a minimum of four courses. There were 11 (23 per cent) deaths, 8 due to uncontrolled bleeding from gastric varices and 3 due to hepatic coma. The other complications of gastric variceal sclerotherapy were minor and included retrosternal pain, fever and dysphagia. It is concluded that gastric varices often coexist with large oesophageal varices. If they persist for 6 months after eradication of oesophageal varices, a combination of paravariceal and intravariceal sclerotherapy should be attempted for their obliteration.  相似文献   
10.
Hip arthroplasty is a common orthopaedic procedure with proven long-term success and reliable results. A wide range of associated conditions may affect the outcome of the arthroplasty and the surgeon has to keep these in mind when planning the surgery. In this article, such situations are discussed and recommendations are drawn from the evidence available in literature.  相似文献   
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