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11.
The relationship between farming and cancer risk was investigated in an integrated series of case-control studies conducted from 1985 to 1991 in the Friuli Venezia Giulia region, north-east Italy. Patients with cancer of the oral cavity and pharynx, larynx, oesophagus, colon and rectum, pancreas, breast, thyroid gland, kidney and urinary tract, bladder, prostate, soft-tissue sarcomas, Hodgkin's diseases, non-Hodgkin's lymphomas and multiple myelomas, and controls admitted to hospital for acute, non-neoplastic conditions, were interviewed. For males, a significantly elevated relative risk was seen for oral cavity and pharynx. Farming, however, was associated with a significant protection against cancer of the colon and rectum and bladder. In females, only one significant association emerged, for multiple myeloma. A few significant interactions between cancer risk and year of birth (i.e., before 1930 or 1930 and after) were observed. The risk of cancer of the larynx was significantly elevated in younger male farmers but not in older ones. Our multi-site case-control study confirms that farmers have, for some cancer sites, a distinctive pattern. Excesses of cancer of the oral cavity and pharynx in farmers are characteristic of the present study area and, possibly, of similar European rural populations who have in common high levels of alcohol consumption and, at least in the past, unbalanced diets.  相似文献   
12.
Omphalocele is the most common congenital defect of the abdominal wall. Mortality rate is between 20 and 70% and early closure of the abdominal wall, within 10 days of life, is vital to the successful outcome of the surgical treatment. The authors describe the use of two bipedicled flaps of abdominal skin to correct the defect of the midline as soon as the reduction of all viscera has been accomplished.  相似文献   
13.
P-glycoprotein (P-gp) expels hydrophobic substances from the cell, including chemotherapeutic agents and immunosuppressants such as cyclosporin A (CsA) and FK506. Exposure of cultured renal tubular cells to CsA induces P-gp overexpression in cell membranes. Angiotensin II has recently been implicated as the principal factor responsible for progression of interstitial fibrosis induced by CsA. To investigate the in vivo relationships between histological lesions, P-gp overexpression, and intrarenal angiotensin II deposits, we developed a model of chronic CsA toxicity in Sprague-Dawley rats treated with 25 mg/kg/day CsA for 28 and 56 days and fed either a standard maintenance diet or a low-salt diet. Immunohistochemical methods were used to study the expression of P-gp in renal tubular cells and the appearance of intrarenal angiotensin II deposits. Rats treated with CsA developed chronic nephrotoxicity lesions that were more evident in the group fed the low-salt diet. Treatment with CsA induced overexpression of P-gp in tubular cells of the kidney that increased with time. We found that immunohistochemical expression of P-gp was slightly more severe in rats fed a low-salt diet. Intrarenal deposits of angiotensin II were more evident in rats treated with CsA; these deposits also increased with time. This finding was also more relevant in rats given the low-salt diet. The up-regulation of P-gp was inversely related to the incidence of hyaline arteriopathy (r = -0.65; P < 0.05), periglomerular (r = -0.58; P < 0.05) and peritubular fibrosis (r = -0.63; P < 0.05), and intrarenal angiotensin H deposits in animals with severe signs of nephrotoxicity (r = -0.65; P < 0.05). These results support the hypothesis that the role of P-gp as a detoxicant in renal cells may be related to mechanisms that control the cytoplasmic removal of both toxic metabolites from CsA and those originating from the catabolism of signal transduction proteins (methylcysteine esters), which are produced as a result of ras activation in presence of angiotensin II.  相似文献   
14.
Adhesion and spreading of fibroblasts on sepiolite-collagen complexes   总被引:1,自引:0,他引:1  
In this study, adhesion, spreading, and attachment of human fibroblasts on collagen-sepiolite complexes have been studied. The behavior of the cultured cells has been compared to that of fibroblasts cultured on plastic dishes and collagen-coated dishes. This has been considered by studying the time course of the cell attachment and scanning electron microscopic observation of the events occurring during this process. The results obtained allow the conclusion that the collagen-sepiolite complexes are adhesive for cells.  相似文献   
15.
16.
Using short term CTL lines derived from HLA A2/Kb transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/Kb molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity.  相似文献   
17.
Programmed myocyte cell death and activation of the immune system have been shown to occur in patients with congestive heart failure. Besides, unstable angina episodes are likely to be associated with immune activation. Our aim was to evaluate the role of changes in circulating levels of soluble Fas (sFas), suggestive of an enhanced inhibitory response to ongoing apoptosis, and soluble IL2 receptor (sIL2-R), indicative of T-lymphocyte activation, in chronic heart failure and unstable angina pectoris. Thirty patients affected by chronic heart failure (20 idiopathic and 10 ischemic cardiomyopathy) and 13 patients with unstable angina were evaluated. Twenty healthy individuals matched for age and gender were used as controls. A complete biochemical determination of indexes of myocardial damage including cardiac troponin I (cTnI) and creatine kinase (MB/CK) was performed. The results demonstrated that mean levels of sFas and sIL2-R were significantly increased in patients affected by chronic heart failure and unstable angina and were not associated with changes in renal function or with serum levels of cTnI. Highest values of sFas were found in NYHA class IV patients (IV NYHA class = 7.39 ± 0.52 vs. controls = 1.34 ± 0.12 ng/ml; P < 0.01) and more elevated in idiopathic than in ischemic cardiomyopathy (3.64 ± 0.40 vs. 1.82 ± 0.37 ng/ml; P < 0.01). Moreover, in chronic heart failure patients sFas and ejection fraction were negatively correlated (P = 0.01), whereas sFas and sIL2-R were positively correlated (P < 0.01). In unstable angina patients too, sFas and sIL2-R appeared to be correlated (P = 0.03); whereas sFas (angina group = 3.18 ± 0.39 vs. controls = 1.34 ± 0.12 ng/ml; P < 0.01) and sIL2-R (angina group = 0.46 ± 0.11 vs. controls = 0.00 UI/ml; P < 0.01) were higher in angina group than in controls. In most of the cases, the increase of sFas was associated with comparable changes in sIL2-R serum levels, indicating that the activation of Fas system is strictly associated with autoimmune–inflammatory reactions. This phenomenon, both in chronic heart failure and in unstable angina, occurs in the absence of biochemical evidences of myocardial damage and seems to parallel the activation of T cell. Soluble Fas could have a role in sustaining inflammatory response and in prolonging the detrimental effects correlated with it in chronic heart failure and angina pectoris.  相似文献   
18.
Genotyping with flanking DNA markers was used to ascertain Treacher Collins Franceschetti syndrome (TCOF1) in a subject affected by tetralogy of Fallot and cryptorchidism. The proband's family consisted of a father and sister who were affected by the disease, and a healthy mother. Since cardiac malformation and cryptorchidism have been associated with the TCOF1 syndrome, the proband was suspected to be a carrier of the mutated gene. Microsatellite markers D5S527, SPARC and D5S519, which previously mapped the TCOF1 gene within a 2.1-cM interval on chromosome 5 (5q32–33.1), were used to follow the transmission of the TCOf 1 mutated locus. Flanking markers D5S519 and D5S527 were informative and enabled us to exclude inheritance of a TCOF1 mutation to the proband, while showing that cardiac malformation and cryptorchidism were unrelated in mis patient.  相似文献   
19.
ABSTRACT  Renal agenesis (RA) appears to be a multifactorial condition with combined genetic and environmental influences. We performed a retrospective case-control study of reproductive history of 26 isolated RA live births cases referred to Sicilian Registry of Congenital Malformations. A statistical significant association for birth weight if we considered all RA together and for bilateral RA alone, an increasing risk for maternal age only in the bilateral RA subgroup and a male predominance both for unilateral and bilateral RA was found. Our results show that some reproductive risk factors may be associated with RA, moreover differences found between subgroups indicate that some risk factors may be different in unilateral and bilateral RA. The association between reproductive risk factors and RA may reflect pathogenetic interaction between genetic and environmental factors. Nevertheless further studies are needed to clarify these associations and to explore the role of perinatal factors in the etiology of renal agenesis. In fact if prenatal or perinatal risk factors are in a causal chain influencing the risk for developing RA, then these data could have important implications in the prevention or treatment of this condition.  相似文献   
20.
Six-year survival of cirrhosis was assessed in a series of 1155 consecutive patients (751 men, 404 women). Among the men, 33% were alcoholics and 18% were HBsAg positive; corresponding figures for the women were 15% and 6%, respectively. Features of decompensation at first presentation were observed in 63% of the patients. Six-year survival was 54% in compensated and 21% in decompensated patients. No significant differences in survival were found between alcoholics and nonalcoholics. Leading causes of death were liver failure (49%), hepatocellular carcinoma (22%), and bleeding (13%). The prognostic role of 21 variables was evaluated separately in compensated and decompensated patients by the Cox's regression model. The following variables were found to be significant predictors of death risk in compensated patients: male sex, HBsAg positivity, age, prothrombin time prolongation, and esophageal varices. In decompensated disease the significant indicators of death risk were: hepatocellular carcinoma, encephalopathy, hemorrhage, SGOT, esophageal varices, gamma globulins, prothrombin time prolongation, continued abuse of alcohol, HBsAg positivity, gamma glutamyl transpeptidase, and cholinesterase. A simple prognostic index based upon the relative risk coefficient of the significant variables is suggested.Members of the Liver Study Group are: Maria Caltagirone, Gabriella Filippazzo, Giovanni Gatto, Gandolfo Giannuoli, Silvio Margin, Guiseppe Malizia, Lorenzo Maniaci, Maria Pia Marcenó, Alberto Maringhini, Rocco Micciolo, Salvatore Orsini, Fabio Pace, Ugo Palazzo, Linda Pasta, Giuseppina Russo, Rosa Giovanna Simonetti, Mario Spinello, Mario Traina, Mario Valenza, Maria Vinci, Giovanni Vizzini.  相似文献   
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