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111.
After a single intragastric administration of 14C-labelled carcinogenic nitrosocarbaryl, a nitrosated pesticide, the distribution of radioactivity was investigated in the blood and a number of organs in male rats. The animals received 0.25 mg/kg of labelled nitrosamine and were killed following administration at timed intervals between 0.5 h and 24 h.Our results show that the greatest amount of the 14CH3-group was associated with the forestomach, tumor-susceptible tissue; the level of radioactivity is noteworthy but less important in the glandular stomach. There are also sites of radioactivity accumulation mainly in the liver. Moreover, [14C]nitrosocarbaryl was revealed in the blood suggesting that nitrosamine itself rapidly (0.5 h) crosses the intestinal barrier and in a significant quantity (13%). These facts constitute a potential carcinogenic risk.  相似文献   
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The authors discuss the case of a 36 year old woman who, for several years, has been delirious and who has shown signs of an affective disorder, alternatively suffering from hypomanic and depressive episodes. What is most interesting is that she expresses erotomaniac delusions while she is elated and persecutory delusions while she is depressed. The authors propose an psychopathological explanation for her disorder.  相似文献   
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We retrospectively investigated the outcome of 30 newly diagnosed patients with mantle cell lymphoma treated with high-dose therapy and autologous stem cell transplantation in first response. With a median follow-up of 55 months, the 5-year overall-survival is 62%, the 5-year progression-free-survival is 40% and no secondary malignancy has occurred.  相似文献   
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OBJECTIVE: To devise a score allowing a better measure of the role of social vulnerability (SV) in a woman's attitude toward abortion. STUDY DESIGN: Consecutive sampling and semi-structured personal interviewing of 2641 women requesting legal termination of pregnancy from 1994 to 2001 in the county of Roanne, France. RESULTS: SV was estimated from each woman's situation with reference to work, family composition, marital status, health insurance status and characteristics of neighbourhood of residence. It was correlated with the income and home ownership situation. With a high SV level taken as reference, the relative risks (RR) of severe, moderate, and low SVP, respectively, were equal to 3.3 (1.8-6.1), 4.6 (2.5-8.6) and 7.2 (3.9-13.1) in women under 18.5 years of age; 1.2 (1.0-1.5), 2 (1.4-2.8), and 2.1 (1.4-3.2) from 18.5 to 19 years of age; 0.7 (0.6-0.8), 0.6 (0.5-0.8) and 0.4 (0.3-0.5) in those aged 19-28; and 0.9 (0.9-1), 0.7 (0.6-0.8) and 0.71 (0.6-0.8) in those over 28. The use of different basic hypotheses (cumulative time of pregnancy in women's life, withdrawal or restarting of the clock after each event in the case of recurrence) resulted in slight modification of the age cut-off points and the amplitude of RR also differed, but their order relative to SV categories was unchanged. CONCLUSIONS: At the individual level knowledge of SV allowed a good estimate of a woman's attitude to an unwanted pregnancy, and SV must be taken into consideration when future actions are planned.  相似文献   
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In vivo measurement of time-resolved autofluorescence at the human fundus   总被引:3,自引:0,他引:3  
An experimental setup for measurement of time-resolved autofluorescence of the human eye fundus is demonstrated. The method combines laser scanning technique and time-correlated single photon counting. The light source is a laser diode, delivering pulses of about 100 ps duration at a repetition rate of 40 MHz. The excitation wavelength is 446 nm and the cutoff wavelength of fluorescence detection is at 475 nm. The autofluorescence can be determined with a spatial resolution of 80 x 80 microm2 and 25 ps time resolution. The fluorescence decay is optimally approximated by a biexponential model. The dominating lifetime tau1 is shortest in the macula (320 to 380 ps) and reaches 1500 ps in the optic disk. The lifetime tau2 varies between 2 ns and 5 ns, but the spatial distribution is more homogeneous. Respiration of 100% oxygen for 6 min leads to changes in the fluorescence lifetime pointing to detection of coenzymes. Diagrams of lifetime tau2 versus tau1 are well suited for comparison of substances. Such lifetime clusters of a 20 deg macular field of a young healthy subject and of a patient suffering from dry age-related macular degeneration overlap only partially with tau2-tau1 clusters of lipofuscin.  相似文献   
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A 30-year-old man who presented with delayed puberty and infertility was found to have hypogonadism associated with an absence of circulating luteinizing hormone. The patient had a homozygous missense mutation in the gene that encodes the beta subunit of luteinizing hormone (Gly36Asp), a mutation that disrupted a vital cystine knot motif and abrogated the heterodimerization and secretion of luteinizing hormone. Treatment with human chorionic gonadotropin increased circulating testosterone, promoted virilization, and was associated with the appearance of normal spermatozoa in low concentrations. This case illustrates the important physiological role that luteinizing hormone plays in male sexual maturation and fertility.  相似文献   
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