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71.
Fertility of male workers exposed to cadmium, lead, or manganese.   总被引:13,自引:0,他引:13  
The effect of exposure to cadmium, lead, or manganese on male reproductive function was examined in 1988-1989 in Belgian blue-collar workers. The workers were exposed to cadmium in two smelters (n = 83; geometric mean urinary cadmium level = 6.94 micrograms/g of creatinine; mean duration of exposure = 24 years), to lead in a battery factory (n = 74; mean blood lead level = 46.3 micrograms/dl; mean duration of exposure = 10.7 years), or to manganese (manganese dioxide) in a dry alkaline battery plant (n = 70; median atmospheric concentration of total manganese dust = 0.71 mg/m3; mean duration of exposure = 6.2 years). Fertility in these workers and in an unexposed population (n = 138) was assessed by examining the birth experiences of their wives through a logistic regression model. The probability of a live birth was not different between the unexposed workers and the cadmium- or manganese-exposed workers before or after the onset of exposure. While the fertility of the lead-exposed workers was somewhat greater than that of the unexposed before the onset of exposure, a significant decrease in fertility was observed during the period of exposure to the metal (odds ratio = 0.65, 95% confidence interval 0.43-0.98).  相似文献   
72.
Journal of Neuro-Oncology - Diffuse intrinsic pontine glioma is a rare disease with a high mortality. Our primary aim was to determine the incidence of this disease in Belgium. Secondly, we wanted...  相似文献   
73.
Ischemia-induced biliary tract lesions, called ischemic cholangitis, often lead to strictures of biliary ducts and cholestasis. Causes of ischemic changes of the biliary tract can be found in the arterial blood supply or in the peribiliary capillary plexus. Known examples are thrombosis after transplantation, intraoperative ligation, or the application of chemotherapeutic drugs. Rarely, such changes are due to inflammation of the blood vessels, such as occurs in polyarteritis nodosa or giant cell arteritis. We present a report of a 49-year old man with leucocytoclastic vasculitis after viral infection, influenza vaccination, and antibiotic treatment, leading to florid ischemic cholangitis. We conclude that hypersensitivity vasculitis must be included in the differential diagnosis of cholestasis and cholangitis.  相似文献   
74.
Aim. To study the efficacy of vagus nerve stimulation (VNS) therapy in a highly drug‐resistant childhood epilepsy patient group and to investigate the effect of age at implantation on efficacy. Methods. The efficacy of VNS treatment was analysed in a cohort of 70 patients with drug‐resistant epilepsy. Both children with focal (n=16) and generalized epilepsies (n=54) were included. Age at implantation varied between 19 months and 25 years. Results. Overall, responder rate was 54% with 5.7% children becoming seizure‐free. The only factor in our analysis that could predict good outcome was age at implantation. In the youngest group (<5 years), the responder rate was 77% and this group also included three of the four seizure‐free children. These three seizure‐free children were known to have tuberous sclerosis. There were no outcome differences between generalized and focal epilepsies. Conclusions. Our single centre study confirms previous studies on the efficacy of VNS in children. A larger study using multivariate analysis to disentangle the contribution of different factors (such as age at implantation, aetiology, and epilepsy duration) is necessary to confirm our preliminary finding that younger age at VNS implantation might result in a better outcome.  相似文献   
75.
Intravascular optical coherence tomography (IVOCT) has become the imaging modality of choice for the evaluation of coronary artery disease and percutaneous coronary intervention (PCI). Both for clinical practice and research, there is a growing interest in 3-dimensional (3D) visualization, as this gives a more comprehensive and intuitively easier to understand representation, compared with 2-dimensional, cross-sectional images. Integrating 3D-IVOCT with classic X-ray angiographic images offers additional advantages and the prospect of integrating IVOCT in fluoroscopic guidance during PCI. Different vendors of IVOCT technology already provide integrated 3D rendering software in their consoles, making 3D images available at the ‘push-of-a-button’. In this review, we will discuss (1) the basic principles and elaboration of 3D-IVOCT in recent years, (2) the feasibility and potential advantages of co-registration with X-ray angiography, (3) the currently available solutions for 3D imaging and their potential clinical applications, and (4) the ongoing development of applications for advanced 3D visualization.  相似文献   
76.
77.
IntroductionThe free radial forearm (FRFA) flap is universally still considered as the gold standard technique in penile reconstruction. Typically, a considerably large flap is required, often involving almost the entire circumference of the forearm. Partial necrosis may occur at the distal-most (dorsoradial) part of the flap as a result of insufficient perfusion.AimTo describe a new technique using the posterior interosseous artery (PIOA) to supercharge FRFA phalloplasty.MethodsIn a 12-month period, all patients having FRFA flap phalloplasty were enrolled. Perioperative, after complete flap dissection, an indocyanine green perfusion scan was performed. In case of insufficient perfusion at the distalmost part of the flap, a supramicrosurgical anastomosis was performed between the FRFA pedicle and the PIOA (artery only).Main Outcome MeasuresStudied outcomes included the rate of marginal necrosis, surgical time, postoperative posterior interosseous nerve damage and urethral complications (fistula, stenosis or necrosis).ResultsA total of 27 FRFA flap phalloplasties was performed. Anastomosis of the PIOA was needed in 15 cases. No marginal necrosis was observed in these cases. There were no cases of postoperative posterior interosseous nerve damage. There were no significant differences in urethral complications (fistula, stenosis or necrosis) between the 2 groups.Clinical ImplicationsIn selected cases where insufficient perfusion of the dorsoradial part of the flap is present, patients may benefit from arterial supercharging to prevent postoperative marginal necrosis.Strength & LimitationsStrengths include a single surgeon, thus lending continuity of skill and technique, a consecutive series, and 100% short-term follow-up. Limitations include single institution series and a limited number of patients.ConclusionArterial supercharging is effective in improving perfusion of large FRFA flaps used in phalloplasty when dorsoradial hypoperfusion is detected on an indocyanine green perfusion scan. It is a technically challenging addition to the standard technique because of the small size of the vessels, the close relationship between the PIOA and the posterior interosseous nerve, and the vulnerability of the newly constructed intra-flap anastomosis.De Wolf E, Claes K, Sommeling CE, et al. Free Bipedicled Radial Forearm and Posterior Interosseous Artery Perforator Flap Phalloplasty. J Sex Med 2019;16:1111–1117.  相似文献   
78.
AIMS:The mechanisms of binding and uptake of hepatitis C-virus (HCV) are critical determinants of the infection-reinfection cycle but due to ongoing absence of a robust cell culture system, these mechanisms are still largely hypothetical. Cryoglobulins are atypical immunoglobulins, present in 40% of HCV patients. The aim of this study was to determine the role of these HCV-containing cryoglobulins as carrier molecules for viral uptake into primary human hepatocytes. METHODOLOGY: Cryoglobulins were precipitated from serum of chronically HCV-infected patients, labeled with biotin and incubated with freshly prepared hepatocytes from human liver tissue. Binding and endocytosis of HCV-cryoglobulins were studied by specific assays, ligand blot analysis and electron microscopy on hepatocellar plasma membranes. RESULTS: Biotinylated HCV-cryoglobulins specifically bound to hepatocytes and inhibitors of homotypic endosomal fusion reduced their uptake and intracellular trafficking, Ligand-blot and electron microscopy analysis revealed adhesion to hepatocellular plasma membranes. Inoculation of human hepatocytes with HCV-cryoglobulins but not serum from the same patients induced HCV infection in vitro. CONCLUSIONS: HCV may enter hepatocytes in conjunction with cryoglobulins via immunoglobulin or related receptors. We hypothesize, that this mechanism plays a role in chronic hepatitis to support the infection-reinfection cycle of the virus.  相似文献   
79.
The prevalence of neuropsychological and respiratory symptoms, lung ventilatory parameters, neurofunctional performances (visual reaction time, eye-hand coordination, hand steadiness, audioverbal short term memory), and several biological parameters (calcium, iron, luteinising hormone (LH), follicle stimulating hormone (FSH), and prolactin concentrations in serum, blood counts, manganese (Mn) concentration in blood and in urine) were examined in a group of workers (n = 92) exposed to MnO2 dust in a dry alkaline battery factory and a matched control group (n = 101). In the battery plant, the current exposure of the workers to airborne Mn was measured with personal samplers and amounted on average (geometric mean) to 215 and 948 micrograms Mn/m3 for respirable and total dust respectively. For each worker, the lifetime integrated exposure to respirable and total airborne Mn dust was also assessed. The geometric means of the Mn concentrations in blood (MnB) and in urine (MnU) were significantly higher in the Mn exposed group than in the control group (MnB 0.81 v 0.68 microgram/100 ml; MnU 0.84 v 0.09 microgram/g creatinine). On an individual basis, MnU and MnB were not related to various external exposure parameters (duration of exposure, current exposure, or lifetime integrated exposure to airborne Mn). On a group basis, a statistically significant association was found between MnU and current Mn concentrations in air. No appreciable difference between the exposed and the control workers was found with regard to the other biological measurements (calcium, LH, FSH, and prolactin in serum). Although the erythropoietic parameters and serum iron concentration were in the normal range for both groups, there was a statistically significant trend towards lower values in the Mn exposed workers. The prevalences of reported neuropsychological and respiratory symptoms, the lung function parameters, and the audioverbal short term memory scores did not differ between the control and exposed groups. The Mn workers, however, performed the other neurofunctional tests (visual reaction time, eye-hand coordination, hand steadiness) less satisfactorily than the control workers. For these tests, the prevalences of abnormal results were related to the lifetime integrated exposure to total and respirable Mn dust. On the basis of logistic regression analysis it may be inferred that an increased risk of peripheral tremor exists when the lifetime integrated exposure to Mn dust exceeds 3575 or 730 micrograms Mn/m3 x year for total and respirable dust respectively. The results clearly support a previous proposal by the authors to decrease the current time weighted average exposure to Mn dust.  相似文献   
80.
Skeinoid fibers are interstitial collections of a pathological collagen, most often seen in gastrointestinal stromal tumors. They were first described in 1991. We report two cases of intestinal stromal tumors, one in an exceptionally young patient with excessive skeinoid fiber deposition. The microscopic as well as the ultrastructural findings of skeinoid fibers are demonstrated and their role is discussed considering the newest literature.  相似文献   
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