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MRI at 7 Tesla has been used to investigate the accumulation of manganese in the occipital cortex of common marmoset monkeys (Callithrix jacchus) after administering four fractionated injections of 30 mg/kg MnCl2 · 4H2O in the tail vein. We found a statistically significant decrease in T1 in the primary (V1) and secondary (V2) areas of the visual cortex caused by an accumulation of manganese. The larger T1 shortening in V1 (ΔT1 = 640 ms) relative to V2 (ΔT1 = 490 ms) allowed us to robustly detect the V1/V2 border in vivo using heavily T1‐weighted MRI. Furthermore, the dorso‐medial (DM) and middle‐temporal (MT) areas of the visual pathway could be identified by their T1‐weighted enhancement. We showed by comparison to histological sections stained for cytochrome oxidase (CO) activity that the extent of V1 is accurately identified throughout the visual cortex by manganese‐enhanced MRI (MEMRI). This provides a means of visualizing functional cortical regions in vivo and could be used in longitudinal studies of phenomena such as cortical plasticity, and for non‐destructive localization of cortical regions to guide in the implementation of functional techniques. Published in 2009 by John Wiley & Sons, Ltd.  相似文献   
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Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%.  相似文献   
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Objective Uveal melanoma is a rare disease with poor prognosis and largely unknown etiology. We studied potential occupational risk factors.Methods A population based case-control study was undertaken during 1995–1997 in nine European countries using population and colon cancer controls with personal interviews. Occupational exposure to sunlight and artificial UV radiation was assessed with a job exposure matrix. In total, 320 uveal melanoma cases were eligible at pathology review, and 292 cases were interviewed, participation 91%. Out of 3357 population controls, 2062 were interviewed, 61%, and out of 1272 cancer controls 1094 were interviewed, 86%.Results Using population controls, occupational exposure to sunlight was not associated with an increased risk (RR=1.24, 95% CI=0.88−1.74), while an excess risk found with use of colon cancer controls was attributed to confounding factors. An excess risk in welders was restricted to the French part of the data. Cooks, RR=2.40; cleaners, RR 2.15; and laundry workers, RR=3.14, were at increased risk of uveal melanoma.Conclusion Our study does overall not support an association between occupational sunlight exposure and risk of uveal melanoma. The finding of an excess risk of eye melanoma in cooks in several European countries is intriguing.  相似文献   
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Perineal hernia (PH) is formed by the protrusion of intra-abdominal viscera through a defect in the pelvic floor. This is a rare complication after conventional abdominoperineal resection, pelvic exanteration, proctectomy, and other pelvic procedures. The purpose of the present paper is to report 4 cases of PH after laparoscopic abdominoperineal resection for rectal cancer and to review literature data about the incidence, predisposing factors, and treatment of this challenging problem. When added to other 3 cases previously reported in the Brazilian series of laparoscopic surgery, this group of 7 cases comprises a PH incidence of 3.5% after rectal resection procedures. Surgical treatment is indicated only in symptomatic patients with no signs of cancer recurrence. Proposed methods of surgical repair include abdominal, perineal, or combined approaches to the hernia in association with the use of autologous tissues or prosthetic meshes. Preventive measures are represented by closure of the pelvic peritoneum whenever possible, primary perineal suture and wound care to avoid infection.  相似文献   
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Neonatal lupus erythematosus (NLE) is an infrequent disease in newborns caused by the transplacental passage of maternal Anti-Ro/SSA, Anti-La/SSB and/or Anti-U1 RNP antibodies. The most common manifestations are cutaneous and cardiac. We carried out a retrospective study of cases of NLE diagnosed in the last 10 years at the Hospital Universitario Insular in Gran Canaria. Complete data was obtained for 4 patients. Three cases had circulating Anti-Ro antibodies in the mother and in the newborns, while in the fourth case they were Anti-RNP. Two mothers were diagnosed with systemic lupus, one with mixed connective tissue disease and the other with leucocytoclastic vasculitis. The skin lesions consisted of urticaria-like and desquamative lesions. One patient presented with ulceration. The histological study of the urticaria-like lesions showed a non-specific perivascular infiltrate; the desquamative lesions were consistent with subacute lupus erythematosus.  相似文献   
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