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Biological monitoring of welders employed in a power plant showed urinary nickel levels largely exceeding the reference values (Ni-U welders mean = 43.2, S.D. = 22.1 micrograms/24 h; Ni-U reference values mean = 2.7, S.D. = 1.4 micrograms/24 h). Subsequently urinary excretion levels of other metals (Cr, Zn, Fe, Mn, Cu, Al, Pb) were measured for a more complete assessment of occupational exposure of these subjects; only aluminum and lead were found to slightly exceed the reference values and correlate with urinary nickel levels. As a consequence of these results, some adjustments in personal prevention measures were introduced at the workplace; the subsequent biological monitoring checks showed a progressive reduction in urinary nickel excretion levels over time in all welders.  相似文献   
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A complete mole coexisting with dichorionic twins was diagnosed by the combined use of sonography and chorionic villus sampling at 10 weeks gestation. The pregnancy resulted in the death of one fetus at 31 weeks from presumed feto-maternal haemorrhage, while the other fetus survived in good condition. A summary of the available literature, combined with this report, reveals a total of seven pregnancies with twins and a coexistent complete mole. Only two out of 14 fetuses survived. Maternal complications included one case of pre-eclampsia and one persistent trophoblastic tumour. Accurate diagnosis of complete mole is possible by genetic analysis of chorionic villi obtained with standard transabdominal sampling. Twins with a coexistent complete mole will usually undergo miscarriage. However, fetal survival is possible and the maternal risks seem limited. A concomitance between gestational trophoblastic disease and the occurrence of feto-maternal haemorrhage is observed.  相似文献   
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This report describes the C-to-B capsular switching in four Neisseria meningitidis strains belonging to the electrophoretic type 37 (ET-37) complex. In particular, one strain belonged to the new sequence type 1860, which was first detected in the year 2000 in Italy and is now frequently isolated. The presence of switched serogroup B strains deserves special attention if they prove as able to spread as their serogroup C progenitors belonging to the hypervirulent ET-37 complex.  相似文献   
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Sixty-three cementless Mallory-Head HA-coated femoral prostheses (Biomet, Warsaw, IN) were used in primary total hip arthroplasty in 50 patients with osteoarthritic hips because of congenital hip dysplasia. The implanted cup was also cementless (41 Harris Galante and 22 Ringlock). The patients were followed up for a mean period of 75.1 months (range, 44-110). Clinical and radiologic analysis were performed. Harris Hip Score increased from 42 to 90 points; 97% of the patients had no or only mild pain, and limping decreased from 90% to 20%. Complications were marginal: no infections, one habitual dislocation, one peroperative fracture of the femur, and one transient ischiadic nerve palsy. Two HG cups were revised for augmented polyethylene wear. Radiographically, no subsidence of the prosthesis or bone atrophy of the proximal femur could be detected. No correlations were found between the radiologic phenomena and the clinical outcome, but the tightness of the prosthesis fit had a definitive influence on the radiographic bone remodeling pattern. The cementless Mallory-Head HA-coated femoral prosthesis shows excellent clinical and radiological mid-term results in osteoarthritic hip dysplasia patients. There was no need for the use of a specially designed dysplasia femoral prosthesis.  相似文献   
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The crystallization and thermal behaviour of crystallizable random propene/ethene copolymers (P-co-E) was systematically investigated. Index of crystallinity and, index of γ-form, enthalpy and entropy of fusion, equilibrium melting temperature, spherulite growth rate, and overall kinetic rate constant were determined and correlated with the overall ethene content and with the concentration of specific chemical defects as determined by 13C NMR analysis (PEP, EPP, EPE triads). The samples of the copolymers, obtained with very-high-yield Ziegler-Natta catalysts, were characterized by IR, 13C NMR, wide angle X-ray scattering, and differential scanning calorimetry.  相似文献   
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The morphological and functional basis of the excellent clinical outcome of ileal orthotopic neobladders are largely unknown. Only long-term follow-up studies will provide an adequate answer to this unsettled question. We have studied a patient who underwent this type of surgery over 27 years ago. Besides an important secretive adaptation we have found, at the ultrastructural level, that the monolayered epithelium does not show signs of true metaplasia and that changes had occurred in the intercellular junctions, namely that desmosomes are significantly increased. Although limited to a single case, these features, if confirmed by further observations, suggest a working hypothesis for the understanding of the definitive phenotypic adaptation of the ileal epithelium to the new aggressive environment.  相似文献   
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PURPOSE AND METHODS: A multicentre phase II trial (single-stage design) was undertaken to test the activity and toxicity of carboplatin (AUC 5 according to Calvert, day 1) plus vinorelbine (25 mg/m(2) days 1 and 8) with lenograstim support, every 3 weeks in the first line treatment of elderly patients, aged 65 or more, affected by extensive small-cell lung cancer (SCLC). The primary end-point of the trial was the objective response rate. Twenty-three responses among 37 patients were considered necessary to proceed to a phase III trial. RESULTS: Twenty-eight patients were enrolled (median age 70 years). Treatment was remarkably toxic. Three patients died while on treatment. Eleven patients (39.3%, 95% exact confidence interval (CI): 21.5-59.4) had an objective response, that was complete in 2 cases. Median time to progression was 5.1 months (95% CI: 3.3-6.7). Median survival was 7.9 months (95% CI: 4.8-14.4). CONCLUSION: Carboplatin plus vinorelbine is poorly tolerated and not sufficiently active to warrant phase III comparison with standard chemotherapy regimens in elderly patients with extensive SCLC.  相似文献   
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