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11.
Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.  相似文献   
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Skin-graft rejection in mice experimentally infected with Schistosoma mansoni is delayed when grafting is performed 60 days after the infection. In mice infected 30 days prior to the grafting, the grafts were rejected at the same time both in infected and in control animals. This observation indicates that impairment of cell-mediated immune response occurs in mice with mature S. mansoni infections.  相似文献   
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The saliva of an individual with selective IgA deficiency was found to contain IgG and IgM, with some of the IgM linked to secretory component. Some specimens showed evidence of low molecular weight immunoglobulin fragments, presumed to be the result of proteolysis.  相似文献   
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Coelho MJ  Cabral AT  Fernande MH 《Biomaterials》2000,21(11):1087-1094
Well-characterised human osteoblastic bone marrow cell cultures are a useful in vitro tool to analyse bone tissue/biomaterials interactions. In this work, human bone marrow was cultured in experimental conditions described to favour osteoblastic differentiation and, serially passaged cells were cultured in two widely used culture media, minimum essential medium Eagle, alpha modification (alpha-MEM) and Dulbecco's modified Eagle's medium (DMEM). Cultures were grown for 35 d and compared concerning morphologic appearance on scanning electron microscopy (SEM), cell viability/proliferation, total protein content, activity of alkaline phosphatase (ALP) and ability to form calcium phosphate deposits. Results showed that cell proliferation was similar in cultures grown in the two media but ALP activity and ability to form mineralised deposits were lower in DMEM cultures. In both experimental situations, osteoblastic parameters were strongly reduced on cell passage, particularly from the first to the second subculture. In the experimental conditions used (presence of ascorbic acid, sodium beta-glycerophosphate and dexamethasone in the primary and secondary cultures), osteoblastic differentiation was observed in the first and second subcultures grown in alpha-MEM and in the first subculture grown in DMEM. These results underline the importance of the definition of the experimental conditions in studies involving bone cell cultures.  相似文献   
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Work undertaken to investigate the effect on EEG responses of ocular artefact removal by proportional electro-oculogram subtraction using the least-squares method is reported. The ocular artefact model and the least-squares approach to estimation of the model parameters and hence of the EEG waveform, including the response, are described. Results are presented to show that the response shapes become modified if ocular artefact removal is implemented recursively. This happens because the response is incorrectly treated as part of the random background EEG. The solution is to incorporate a model of the response within the ocular artefact removal algorithm. The results of tests on simulated data confirm these conclusions. The results of the incorporation of response models in removing ocular artefacts from CNV recordings are presented. Even with modelling recursive ocular artefact removal is found to modify the shape of the CNV, and so reliable results can only be obtained if the removal is implemented nonrecursively. Evidence is given that it is advisable to remove DC levels from the recorded data.  相似文献   
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Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
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BackgroundIntrahepatic lithiasis (IHL) is a rare disease in the western world. Complications associated with IHL include acute cholangitis, liver atrophy, secondary biliary cirrhosis, and risk for intrahepatic cholangiocarcinoma. Liver resection is considered the treatment of choice for IHL. The objective of this study was to analyze patients who underwent liver resection for non-Asian hepatolithiasis.Methods127 patients with symptomatic non-Asian hepatolithiasis underwent resection in six institutions. Demographic data, clinical presentation, diagnosis, classification according to stone location, presence of atrophy, bile duct stricture, biliary cirrhosis, incidence of cholangiocarcinoma, treatment and postoperative course were evaluated.Results52 patients (40.9%) were male and the mean age was 46.1 years. Sixty-six patients (51.9%) presented with history of cholangitis. Stones were located in the left lobe in 63 (49.6%), and right lobe in 28 patients (22.0%). Atrophy was observed in 31 patients (24.4%) and biliary stenosis in 18 patients (14.1%). The most common procedure performed was left lateral sectionectomy in 63 (49.6%) patients, followed by left hepatectomy in 36 (28.3%), right hepatectomy in 19 (15.0%), and associated hepaticojejunostomy in 28 (22.0%). Forty-two patients (33.0%) presented postoperative complications and the most common were biliary fistula (13.3%) and surgical site infection (7.0%). Postoperative mortality was 0.7%. Intrahepatic cholangiocarcinoma was observed in 2 patients (1.5%). Recurrence was identified in 10 patients (7.8%), mostly with bilateral stones and/or hepaticojejunostomy.ConclusionLiver resection is the standard treatment for symptomatic unilateral or complicated IHL with good operative results. Risk of cholangiocarcinoma was low in non-Asian patients.  相似文献   
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