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1.
Professional exposure to vegetable dusts affect the respiratory function of the exposed subjects. A previous survey conducted in an industrial flour-mill demonstrated a higher frequency of respiratory symptoms in workers compared to a control group. Ten subjects employed in a work site particularly exposed to dust were studied. Each subject answered a questionnaire and performed on Mondays and Fridays, at the begenning and end of his work shift, a flow volume curve and an isocapnic hyperventilation test. The aerobiology of the professional environment was also measured. We noted: 1) in the flow volume curves: a drop in the FEV1 during the Monday morning shift, a significant difference between the FEV1 (p<0.05) and the MMEFR 25–75 (p<0.05) measured at 6 am on Monday and Friday, and between the MMEFR 25–75 values obtained at 12 noon on Monday and Friday (p<0.05). 2) after isocapnic hyperventilation, a significant drop in the MMEFR 25–75 at 6 am on Monday (p<0.01) and in the FEV1 and MMEFR 25–75 at 12 noon on Mondays (p<0.05), a significant drop in the FEV1 at 1 pm on Monday (p<0.01).  相似文献   
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Ruptures of the hepatic artery and hepatic pseudoaneurysms (PA) are rare but serious complications of hepatic transplantation. We conducted a retrospective study of 640 liver transplantations performed in our institution for a variety of pathologies. After surgery, seven major arterial bleeds occurred (0.9%). Of these seven cases, there were due to hepatic artery rupture (HAr) and four to PA rupture; all confirmed at either surgery (six cases) or autopsy (one case). Five of the seven patients died. In all cases the transplantation was difficult. All vascular injuries but one were caused by sepsis and occurred either after an undetermined cause septicemic syndrome (five cases) or graft dysfunction (one case). The last vascular injury was biliary drainage related. Six of the seven patients had imaging studies. Sonography (five cases) found a sub-hepatic hypoechoic collection in three cases but failed to do so in two. Duplex doppler (three cases) failed in all three cases to demonstrate a PA. Computed tomography (three cases) showed one PA, one perihilar sub-hepatic collection and failed in one. Conventional angiography (three cases) depicted a PA in all three cases. At the present time, our practice is to perform systematic angiography in patients with undetermined cause septicemic syndrome to research a PA. And if angiography is normal, to then puncture systematically any sub-hepatic collection to determine the bacteriological nature of this collection. Correspondence to: H. Caillet  相似文献   
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As part of a world survey of the habits, knowledge and attitudes of medical students regarding tobacco we report a study in 15 medical schools from nine Asian countries. Some 1646 first year and 1587 final year students were included, of whom 59% were male. The prevalence of daily smoking in males was 4% in first year and 11% in final year; of occasional smoking 18% and 24% respectively, both with considerable variations between countries. The rates were very low in women. Male exsmokers varied from 3% to 24% in different centres. Overall, 33% of smokers had made a serious attempt to quit; 44% expected to have succeeded within 5 years. Over 80% of non- or exsmokers, but only 60% of smokers, thought smoking was harmful to health. There was gross underestimation of tobacco's causal role in a number of important diseases, e.g. coronary artery disease, peripheral vascular disease, emphysema, bladder cancer and neonatal mortality. There were notable defects both in training and in motivation to counsel smoking patients. There was only partial knowledge of legislative and other measures to discourage smoking, e.g. only 44% of final year students (26% of smokers) thought increased taxation an important measure. In knowledge and attitudes there was little difference between the sexes, but in most aspects smokers had notably lower scores.  相似文献   
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Metastatic tumors of oral cavity are uncommon. Mandibular localisation is the most frequent. Microscopic diagnosis and other metastatic localisations help the diagnosis we are reporting on. The report is on a case with prostatic and lung primitive tumors associated with gingivo-maxillary, femur and cutaneous metastasis.  相似文献   
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Parental-specific epigenetic modifications are imprinted on a subset of genes in the mammalian genome during germ cell maturation. However, the precise timing of their establishment remains to be determined. Methylation of CpG dinucleotides has been shown to be a part of the parental imprint. We have examined how the methylation pattern characteristic of the paternal allele in germ cells are established during human spermatogenesis. Two representative imprinted genes, H19 and MEST/PEG1, were studied. The experiments were performed using the bisulphite sequencing method on microdissected individual cells at different stages of male germ cell differentiation. We show that both genes are unmethylated in fetal spermatogonia, suggesting that all pre-existing methylation imprints are already erased by this stage. The MEST/PEG1 gene remains unmethylated at all subsequent post-pubertal stages of spermatogenesis, including mature spermatozoa. The methylation of H19 typical of the paternal allele first appears in a subset of adult spermatogonia and then is maintained in spermatocytes, spermatids and mature spermatozoa. Our results suggest that the methylation imprint inherited from the parents is first erased in the male germ line at an early fetal stage. The paternal-specific imprint is re-established only later, during spermatogonial differentiation in the adult testis.  相似文献   
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