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The intermediate filament proteins nestin, vimentin, and desmin show a specific temporal expression pattern during the development of myofibers from myogenic precursor cells. Nestin and vimentin are actively expressed during early developmental stages to be later down-regulated, vimentin completely and nestin to minimal levels, whereas desmin expression begins later and is maintained in mature myofibers, in which desmin participates in maintaining structural integrity. In this study we have analyzed the expression levels and distribution pattern of nestin in intact and denervated muscle in rat and in human. Nestin immunoreactivity was specifically and focally localized in the sarcoplasm underneath neuromuscular junctions (NMJs) and in the vicinity of the myotendinous junctions (MTJs), ie, in regions associated with acetylcholine receptors (AChRs). This association prompted us to analyze nestin in neurogenically and myogenically denervated muscle. Immunoblot analysis disclosed a marked overall increase of accumulated nestin protein. Similar to the extrajunctional redistribution of AChRs in denervated myofibers, nestin immunoreactivity extended widely beyond the NMJ region. Re-innervation caused complete reversion of these changes. Our study demonstrates that the expression levels and distribution pattern of nestin are regulated by innervation, ie, signal transduction into myofibers.  相似文献   
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OBJECTIVE: To compare the results of open and laparoscopic fundoplication. DESIGN: Nonrandomized controlled study with a 3-year follow-up. PATIENTS AND METHODS: Fifty-seven consecutive patients with erosive reflux esophagitis underwent laparoscopic (30 patients) or open (27 patients) fundoplication. INTERVENTIONS: Interview by an independent person. In addition, 52 patients (91%) underwent postoperative endoscopy, and 38 patients (67%) underwent esophageal 24-hour pH recording. RESULTS: Temporary dysphagia was reported by 20 patients (67%) after laparoscopic and by 11 (41%) after open fundoplication (P = .05). There were no differences between groups concerning incidence of persistent dysphagia (20% vs 18%, respectively) and mild to no reflux symptoms (97% vs 100%, respectively). In addition, bloating (50% vs 63%, respectively) and increased flatus (77% vs 78%, respectively) were equally common. Visual analog scale scores for dysphagia, bloating, and increased flatus were 0.6, 2.4, and 4.3, respectively, in the laparoscopic and 0.6, 3.5, and 3.4, respectively, in the open groups. Normal belching ability was reported by 12 patients (40%) after laparoscopic and by 20 (74%) after open fundoplication (P = .01). Visick grade 1 or 2 was reported by 21 patients (70%) after laparoscopic and by 24 (89%) after open fundoplication (P = .08). Defective fundic wrap was detected in 4 patients (13%) in the laparoscopic and in none in the open group. In addition, abnormal results of 24-hour pH recording were found in 4 patients (22%) after laparoscopic and in 2 (10.5%) after open fundoplication. CONCLUSION: From a functional point of view, both techniques were equally effective except concerning belching ability and temporary dysphagia.  相似文献   
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We present a series of 19 avulsions of the distal tendon of the biceps brachii muscle after a follow-up of 2 to 11 years. Ten patients with delayed diagnosis and treatment (3 weeks to 5 months) were compared with nine patients treated early (within 8 days after injury). Excellent or good results at follow-up were obtained in 9 of 10 patients in the delayed-treatment group and in all 9 patients in the early-treatment group. Nine of 10 patients in the delayed-treatment group and all patients in the early-treatment group had been able to return to their preinjury levels of activity. For reference, a meta-analysis of 147 cases reported previously was performed. Ninety percent of the patients treated with an anatomic reinsertion had excellent or good results after an average follow-up of 3 years, while similar results after 3 years were seen in 60% of the patients who had nonanatomic tendon reinsertion and in 14% of the patients who were treated nonoperatively. The delay of up to 3 years between injury and anatomic reinsertion had not compromised the result. From these data we concluded that anatomic reinsertion of the avulsed distal biceps tendon to the radius is the preferred treatment in acute as well as chronic injuries.  相似文献   
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Objective.The correlation betweenp53tumor suppressor gene mutations and the presence of high-risk human papillomavirus (HPV) DNA with thein vitroradiosensitivity of gynecological malignancies was studied in 26 cell lines derived from gynecological cancers of 23 patients.Methods.Comparison of the intrinsic radiosensitivity was performed with mean inactivation dose (D?) determined with the 96-well plate clonogenic assay.p53mutations were investigated with polymerase chain reaction and single-strand conformation polymorphism (PCR–SSCP) analysis and direct DNA sequencing, and the presence of HPV DNA was studied with PCR using HPV consensus primers.Results. p53mutations were found in 6 of 10 vulvar squamous cell carcinoma (SCC) lines. Nine vulvar and 1 vaginal SCC cell lines were HPV DNA negative and 1 vulvar cell line was HPV 16 positive. All 4 cervical SCC lines were HPV positive and possessed the wild-typep53.Three cell lines expressed HPV 16 and 1 HPV 68. Among 10 endometrial cancer cell lines, 2 cell lines with mutantp53and 1 HPV 16 positive cell line were found. No correlation could be demonstrated between inactivation of thep53gene and radiosensitivityin vitro;the cell lines were evaluated as one group or according to their anatomical origin or histology.Conclusion.Our results indicate that inactivation of thep53gene through mutation or binding with HPV DNA does not increase the resistance of gynecological malignancies to ionizing radiationin vitro.  相似文献   
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This study investigated the continuity of life‐span physical activity by examining the predictors of the maintenance of a high level of physical activity over 8 years among subjects aged 65–84 years at the baseline, in 1988, in Jyväskylä, Finland. Age, education, marital status and chronic conditions and past physical activity were studied at the baseline. In men and women, self‐reported competitive sport participation from as early as 10–19 years of age was a significant predictor for maintaining activity in old age. Also women’s participation in recreational sports at the age of 40–64 years predicted activity. We concluded that past physical activity is strongly connected to maintaining a high level of physical activity in old age regardless of chronic conditions that may develop.  相似文献   
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