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The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases.  相似文献   
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Despite the introduction of microsurgical techniques into clinical practice, the results of surgical procedures involving the brachial plexus and peripheral nerves are still far from spectacular. We therefore studied the rat brachial plexus and its terminal branches in 203 rats. Detailed anatomic and morphologic analyses of the biceps brachii and musculocutaneous nerve, finger flexors, flexor carpi radialis, and the median nerve were performed. Various sources of conventional and vascularized nerve grafts were explored. After musculocutaneous nerve section or median nerve section, there were no articular contractures or automutilations, which constitutes an advantage for these experimental models over the sciatic nerve model. The brachial plexus and its terminal branches provide a good experimental model which can be used to assess the development and normal control of muscle function, examine the mechanisms underlying functional recovery, and test the effects of treatments to enhance recovery. © 1995 Wiley-Liss, Inc.  相似文献   
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The efficiency of two methods of detection of translocations induced in mouse stem cell spermatogonia by X-ray doses of 2, 5 and 7 Gy was compared: classical multivalent analysis at diakinesis-metaphase I of meiosis and observation via fluorescencein situ hybridization analysis of mitotic or meiotic stages. Specific DNA libraries for chromosomes 1, 11 and 13 were used. The results obtained indicate that (a) chromosomes 1, 11 and 13 are more involved in multivalent formation than expected on the basis of DNA content and (b) if the mitotic FISH analysis data are corrected for the observed over-representation, the frequencies of induced translocations are similar to those recorded in the classical multivalent studies, suggesting equal scoring efficiencies in both systems.  相似文献   
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Blood components have been implicated as factors which modulate organ injury in acute pancreatitis. To isolate these effects we compared a standardized isolated, blood-perfused, canine pancreas model as described by Herman-Taylor and modified by Cameron with a model using fluosol, a fluorocarbon, as the perfusate. Pancreatitis was induced using partial pancreatic duct obstruction with secretin induced hypersecretion. Twenty-four dogs were randomized into four groups; (1) blood-perfused control (BPC), (2) fluosol-perfused control (FPC), (3) blood-perfused injury (BPI), (4) fluosol-perfused injury (FPI). All glands were observed for 4 h for mean arterial pressure (MAP), weight gain, gross appearance, and venous amylase. Stability was monitored with blood gases and glucose. Specimens were taken at 4 h for light and electron microscopy. Results: BPI preps had a significantly higher vascular resistance at 3 and 4 h compared to FPI preps (3.85 vs 3.26 PRU and 4.8 vs 3.9 PRU, respectively) (P less than 0.002). Edema formation (3+ vs 1+) and venous amylase (18,543 vs 1961) (P less than 0.001) were greater in BPI than FPI preps. Light and electron microscopy confirmed injury but could not quantify it between injury groups. Summary: Hypersecretion and partial ductal obstruction causes a more severe injury in the blood than the fluosol perfused preparation. Changes in the peripheral resistance seen in the blood perfused model lend support to the theory that the primary injury in this model is at the capillary level and is modulated by a blood component.  相似文献   
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A vast majority of the transplant recipients are cytomegalovirus (CMV)-seropositive (R+). We sought to assess variables predictive of CMV infection, specifically in R+ liver transplant recipients. Study patients comprised 182 consecutive liver transplant recipients who survived at least 14 days after transplantation. Surveillance testing was used to detect CMV infection. Pre-emptive therapy was employed for the prevention of CMV disease, however, no antiviral prophylaxis was used for CMV infection. CMV infection developed in 32.5% (38 of 117) of R+ patients, 84.6% (33 of 39) of R-/D+, and 3.8% (1 of 26) of R-/D- patients. In R+ patients, Hispanic race (21.6% vs. 7.8%, P = 0.06), donor CMV seropositivity (73.7% vs. 45.6%, P = 0.005), and hepatocellular carcinoma (23.7% vs. 6.3%, P = 0.05) correlated with a higher risk of CMV infection. In a multivariate model, Hispanic race (OR: 3.5, 95% CI: 1.03-11.6, P = 0.045), donor CMV serostatus (OR: 4.0, 95% CI: 1.6-10.2, P = 0.003) and hepatocellular carcinoma (OR: 5.8, 95% CI: 1.6-20.5, P = 0.006) were all significant independent predictors of CMV infection. The aforementioned variables did not portend a higher risk of CMV infection in R-/D+ patients; donor CMV seropositivity overwhelmed all other risk factors in R- patients (P < 0.00001). In conclusion, CMV-seropositive liver transplant recipients at risk for CMV infection can be identified based on readily assessable variables. Preventive strategies may be selectively targeted toward these patients.  相似文献   
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This study examined the number of ambulatory care providers treating individuals with the acquired immunodeficiency syndrome who were Medicaid beneficiaries in New York State in 1988 and examined the distribution of this care across various practice settings. The study population was identified retrospectively in the New York State Medical HIV/AIDS Research Data Base and included a cohort of 5535 individuals with the acquired immunodeficiency syndrome who were enrolled in Medicaid in 1988 for at least 6 months after being diagnosed as having the disease and who had at least one ambulatory care encounter during the year. Ambulatory care for the study group was provided by more than 700 hospital or freestanding clinics and more than 3000 private physicians in 1988. Many sites had low caseloads; 47% of the clinics and 68% of the physicians treating this population saw only one or two patients with the acquired immunodeficiency syndrome who were enrolled in Medicaid. More than half the patients in the study group were seen most frequently in clinics for their ambulatory care during 1988. These data provide reassurance that a wide network of providers is involved in the care of patients with the acquired immunodeficiency syndrome who are Medicaid beneficiaries in New York.  相似文献   
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