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SN Flick PP Roy-Byrne DS Cowley MM Shores DL Dunner 《Canadian Metallurgical Quarterly》1993,27(2):71-79
This study examined the prevalence, comorbidity, and clinical correlates of personality disorders in an outpatient sample (N = 352) with anxiety and depression. Subjects were diagnosed using the Structured Clinical Interview for DSM-III-R (SCID) on Axes I and II, and they also completed interview and self-report measures of symptoms. Subjects with a personality disorder were less likely to be married, more likely to be single or divorced, had lower family incomes, had more severe symptoms of both anxiety and depression, and had a greater number of lifetime Axis I diagnoses. Subjects with dysthymic and bipolar disorders were more likely, and subjects with panic disorder uncomplicated by agoraphobia were less likely to have a personality disorder compared to the rest of the sample. The most prevalent personality disorders were Avoidant, Obsessive-Compulsive, Paranoid, and Borderline. Paranoid co-occurred with Narcissistic, and Borderline co-occurred with Histrionic personality disorder significantly more often than chance and base rates would predict. 相似文献
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OBJECTIVES: Injury is the leading cause of death in the male working population of Brazil. An important fraction of these deaths are work related. Very few cohort studies of steel workers, and none from developing countries, have reported on mortality from injuries. This paper analyses mortality from work and non-work related injuries among Brazilian steel workers. METHODS: Deaths during employment from 1 January 1977 to 30 November 1992 were analysed in a cohort of 21,816 male steel workers. Mortality rates specific for age and calendar year among the workers were compared with those of the male population of the state where the plant is located. Work related injuries were analysed by comparing the mortality rates for different subgroups of the cohort. RESULTS: The number of deaths (391) was less than half that expected based on death rates of the general population. Over 60% (242) of deaths were due to injuries. Mortality from most causes was substantially below that in the general population, but that from unintentional injury, was 50% above that of the general population. Standardised mortality ratios (SMRs) were highest for the youngest and the oldest employees and for labourers and clerical workers. Mortality from motor vehicle injury was twice that expected from population rates (SMR = 209, 95% confidence interval (95% CI) 176-244). There was a 67% fall in the age adjusted mortality from occupational injuries in the study period. CONCLUSION: The healthy worker effect in this cohort was greater than that commonly found in studies of occupational groups in developed countries, probably because of a greater socioeconomic gap between employed and unemployed populations in Brazil, and unequal distribution of health care resources. Mortality was especially high for motor vehicle injuries. The fall in mortality from occupational injuries during the study period was probably due to improvement in safety standards, increased automation, and better medical care. There is a need to investigate risk factors for unintentional injuries among steel workers, especially those due to motor vehicle injuries. Prevention of occupational and nonoccupational injuries should be a main priority in Brazil. 相似文献
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Takamichi Iida Roderick Guthrie Nagendra Tripathi 《Metallurgical and Materials Transactions B》2006,37(4):559-564
By combining the modified Stokes-Einstein formula with the authors’ model for the melting-point viscosity, the authors present
a model for accurate predictions of self-diffusivity of liquid metallic elements. The model is expressed in terms of well-known
physical quantities and has been applied to various liquid metallic elements for which experimental data are available. The
results of calculations show that agreement with experimental data is excellent; the uncertainties in the calculations of
the self-diffusivities in various liquid metallic elements are equal to the uncertainties associated with experimental measurements.
Also, the authors propose an expression for the temperature dependence of self-diffusivity in liquid metallic elements in
terms of melting-point temperature. Using the model, self-diffusivity data are predicted for liquid iron, cobalt, nickel,
titanium, aluminum, magnesium, silicon, and so forth. 相似文献
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Two paramount observations exist regarding aneuploidy in human oocytes: its association with maternal age and its more frequent occurrence during meiosis I. Numerous experimental studies have shown that fertilization of postovulatory aged oocytes is coupled with reproductive failure and cytogenetic aberrations in embryos. However, the basic cytogenetic defect(s) of aged oocytes that causes these abnormalities has not been adequately described. The objective of this study was to test the hypothesis that postovulatory oocyte ageing results in increased frequencies of premature centromere separation (PCS) in metaphase II (MII) oocytes and aneuploidy in zygotes. MII oocytes and one-cell zygotes were collected from superovulated mice at different times after ovulation and fertilization. Chromosomes were C-banded and analyzed for structural and numerical aberrations. The frequencies of PCS in oocytes significantly (p < 0.01) increased with time postovulation: 15 h (15 of 529, 2.8%), 20 h (82 of 627, 13.1%), and 25 h (118 of 502, 23.5%). In zygotes, the frequencies of hyperploidy significantly (p < 0.01) increased with time post-fertilization: 0-4 h (0 of 260), 4-8 h (5 of 212, 2.4%), and 8-12 h (8 of 262, 3.1%). These data support the hypothesis that postovulatory ageing results in elevated levels of PCS in oocytes and of aneuploidy in zygotes. The link between PCS and aneuploidy may be random segregation of sister chromatids during anaphase II. 相似文献
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M Bangerter F Moog I Buchmann J Kotzerke M Griesshammer M Hafner K Elsner N Frickhofen SN Reske L Bergmann 《Canadian Metallurgical Quarterly》1998,9(10):1117-1122
BACKGROUND: Staging of Hodgkin's disease (HD) is accomplished by a variety of invasive and non-invasive modalities. This prospective study was undertaken to investigate the value of whole-body positron emission tomography (PET) with 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) in defining regions involved by lymphoma compared with conventional staging methods in patients with HD. PATIENTS AND METHODS: Fourty-four newly diagnosed patients with HD underwent FDG-PET as part of their initial staging work-up. PET findings were correlated with findings of conventional staging including computed tomography, ultrasound, bone scanning, bone marrow biopsy, liver biopsy and laparotomy. When results of FDG-PET differed to those obtained by conventional methods reevaluation was performed by biopsy, if possible, or magnetic resonance imaging. RESULTS: The results of FDG-PET were compared with three hundred twenty-one conventional staging procedures performed in 44 patients. FDG-PET was positive in 38 of 44 (86%) patients at sites of documented disease. PET detected additional lesions in five cases previously not identified by conventional staging methods. In another case a nodal lesion suspect on CT was negative at FDG-PET and was settled as true negative by biopsy. As a consequence of PET findings five patients had to be upstaged and one patient had to be downstaged, resulting in changes in treatment strategy in all six cases (14%). FDG-PET failed to visualize sites of HD in four patients. In two of our patients a false positive PET result was obtained. CONCLUSIONS: Our data indicate that FDG-PET provides an imaging technique that appears to visualize involved lesions in most patients with HD and is useful in the management of these patients. 相似文献