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71.
Minor changes in PMP22 gene dosage have profound effects on the development and maintenance of peripheral nerves. This is evident from the genetic disease mechanisms in Charcot-Marie-Tooth disease type 1A (CMT1A) and hereditary neuropathy with liability to pressure palsies (HNPP) as well as transgenic animals with altered PMP22 gene dosage. Thus, regulation of PMP22 is a crucial aspect in understanding the function of this protein in health and disease. In this study, we have generated transgenic mice containing 10 kb of the 5'-flanking region of the PMP22 gene, including the two previously identified alternative promoters, fused to a lacZ reporter gene. We show that this part of the PMP22 gene contains the necessary information to mirror the endogenous expression pattern in peripheral nerves during development and regeneration and in mouse models of demyelination due to genetic lesions. Transgene expression is strongly regulated during myelination, demyelination, and remyelination in Schwann cells, demonstrating the crucial influence of neuron-Schwann cell interactions in the regulation of PMP22. In addition, the region of the PMP22 gene present on this transgene confers also neuronal expression in sensory and motor neurons. These results provide the crucial basis for further dissection of the elements that direct the temporal and spatial regulation of the PMP22 gene and to elucidate the molecular basis of the master program regulating peripheral nerve myelination.  相似文献   
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The infraumbilical incision required for open repair of bilateral inguinal hernia with a giant prosthesis is associated with postoperative pain and respiratory impairment. The aim of this study was to evaluate the postoperative respiratory dysfunction after bilateral hernia surgery. Thirty-nine patients were randomized into two groups: open repair according to the Stoppa technique and laparoscopic extraperitoneal repair (TEPP). Respiratory function tests were performed before and 24 hours after surgery. The two groups were well matched for age, American Society of Anesthesiologists (ASA) risk score, type of hernia, and preoperative lung function. The postoperative forced vital capacity (FVC), peak expiratory flow (PEF), and forced expiratory volume in 1 second (FEV 1.0) were significantly altered in both groups. The PEF dropped 15% in both groups. The FVC dropped 22% after Stoppa versus 25% after laparoscopy (P = 0.7). The FEV 1.0 dropped 21% after Stoppa versus 9% after laparoscopy (P = 0.12). We conclude that laparoscopic preperitoneal and open bilateral hernia repair are followed by similar ventilatory dysfunction, although a trend toward better postoperative FEV 1.0 was noted after laparoscopy. This might play a role in selected patients with severe pulmonary limitations. Overall, the limited drop in pulmonary function following bilateral hernia repair under general anesthesia may serve to explain the low pulmonary morbidity that follows these procedures.  相似文献   
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Clinical evaluation of biomarkers in Gaucher disease   总被引:1,自引:0,他引:1  
Novel or candidate biomarkers require thorough evaluation to establish their utility in a clinical setting. This paper describes an evaluation of several established enzyme markers of Gaucher disease and a newly-described chemokine, pulmonary and activation-regulated chemokine (PARC). The ability of the biomarkers to rank patients with Gaucher disease in order of disease severity and organ bulk, and to reflect changes in key clinical parameters in response to enzyme replacement therapy were evaluated. PARC concentrations were found to be reliably correlated with visceral disease and with key clinical responses to enzyme replacement in an unbiased manner. Unlike chitotriosidase and serum angiotensin-converting enzyme activity, genetic variation in serum PARC did not appear to influence its utility as a biomarker.
Conclusion: For each new candidate biomarker of lysosomal storage diseases, a similar clinical evaluation will be required, though the approach will need to be modified according to the clinical features and natural history of each disorder.  相似文献   
75.
Knee pathologies are commonly associated with muscle inhibition, an inability to fully activate the knee extensors during voluntary contractions. This inhibition results in knee extensor weakness, and is thought to limit the functional recovery of the knee joint structures. The possible contribution of persistent knee extensor inhibition to osteoarthritis is discussed.  相似文献   
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背景:作者制定了一个应用软X线治疗表皮恶性肿瘤的计划,该计划虑及临床已诊断的肿瘤在治疗下的退化现象。目标:根据治愈率和后期溃疡形成来评价本计划的有效性。方法:对1988-1992年间接受连续照射的1267例基底细胞癌和鳞状细胞癌患者进行随访(平均随访77个月)。结果:肿瘤复发率5.1%,与其大小、厚度及时间-剂量分次因子有关。溃疡形成率6.3%,取决于照射野大小、X线的硬度,在一个较小照射野(直径≤4cm)内则与总的照射剂量和时间-剂量分次因子有关。82.5%的溃疡能适当治愈。局限性:尚无证据表明本方案优于其他文献报道的方案。结论:软X线对表皮恶性肿瘤是有效的。  相似文献   
77.
Because of the potential for complications with laparotomy and splenectomy, and the widespread use of combination chemotherapy as first-line treatment, surgical staging is now performed in only 30% of patients with Hodgkin disease. Laparoscopic staging has rarely been reported. Three patients with the nodular sclerosis cell type of Hodgkin disease underwent laparoscopic staging. Mean operative time was 207 minutes. No conversion to laparotomy was necessary. There were no peri- or postoperative complications and no deaths. Mean blood loss was negligible. The pathologist deemed all liver and lymph nodes biopsies adequate for histologic analysis. Stage IA and IIA were confirmed in two patients: one patient with stage IIA was upstaged to IIIA after surgery. Performed by an experienced team, laparoscopy is the procedure of choice for abdominal staging of patients with Hodgkin disease.  相似文献   
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Suter PM  Vetter W 《Nutrition reviews》2000,58(10):319-323
Despite modern pharmacologic agents in the therapy of heart failure, the prevalence of heart failure is increasing worldwide. In the vitamin B1 deficiency disease beriberi, cardiac symptoms may represent the central feature. Two new studies confirmed that all diuretics lead to increased urinary thiamin excretion depending on the urinary flow rate. In a subject at risk, such as an elderly patient, chronic diuretic treatment may lead to a subclinical thiamin deficiency. Whether subclinical thiamin nutriture is a modulator of the prevalence and/or severity of heart failure is not known; however, it seems to be plausible from the metabolic point of view.  相似文献   
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