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Though very rare compared to imported malaria, airport malaria should not be disregarded considering its very special gravity often due to late diagnosis. In most cases, it could be avoided if airlines and airports applied disinsecting measures vigilantly. 相似文献
993.
CM Fraser SJ Norris GM Weinstock O White GG Sutton R Dodson M Gwinn EK Hickey R Clayton KA Ketchum E Sodergren JM Hardham MP McLeod S Salzberg J Peterson H Khalak D Richardson JK Howell M Chidambaram T Utterback L McDonald P Artiach C Bowman MD Cotton C Fujii S Garland B Hatch K Horst K Roberts M Sandusky J Weidman HO Smith JC Venter 《Canadian Metallurgical Quarterly》1998,281(5375):375-388
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BACKGROUND: Among the victims of floods, earthquakes, and hurricanes, there is an increased prevalence of post-traumatic stress disorder and depression, which are risk factors for suicidal thinking. We conducted this study to determine whether natural disasters affect suicide rates. METHODS: From a list of all the events declared by the U.S. government to be federal disasters between 1982 and 1989, we selected the 377 counties that had each been affected by a single natural disaster during that period. We collected data on suicides during the 36 months before and the 48 months after the disaster and aligned the data around the month of the disaster. Pooled rates were calculated according to the type of disaster. Comparisons were made between the suicide rates before and those after disasters in the affected counties and in the entire United States. RESULTS: Suicide rates increased in the four years after floods by 13.8 percent, from 12.1 to 13.8 per 100,000 (P<0.001), in the two years after hurricanes by 31.0 percent, from 12.0 to 15.7 per 100,000 (P<0.001), and in the first year after earthquakes by 62.9 percent, from 19.2 to 31.3 per 100,000 (P<0.001). The four-year increase of 19.7 percent after earthquakes was not statistically significant. Rates computed in a similar manner for the entire United States were stable. The increases in suicide rates were found for both sexes and for all age groups. The suicide rates did not change significantly after tornadoes or severe storms. CONCLUSIONS: Our study shows that suicide rates increase after severe earthquakes, floods, and hurricanes and confirms the need for mental health support after severe disasters. 相似文献
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AE Peaston ML Camacho MD Norris M Haber DJ Marsh BG Robinson VJ Hyland GM Marshall 《Canadian Metallurgical Quarterly》1998,12(4):239-242
A spectroscopic method for thiol analysis, based on the complexation reaction with Pd(II), is described. The proposed method is simple and sensitive and can be used for a rapid analysis of thiols in human lymphocytes. 相似文献
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RH Dowling MJ Veysey SP Pereira SH Hussaini LA Thomas JA Wass GM Murphy 《Canadian Metallurgical Quarterly》1997,11(1):57-64
The aim of the study was to compare the occurrence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia in the subgingival plaque from sites with and without early periodontitis in adolescents using an ELISA. 47, 15- to 16-year-old adolescents (39 Indo-Pakistani, 8 white Caucasian) were examined for clinical attachment level, probing depth, supragingival plaque, subgingival calculus and bleeding on probing on the mesio-buccal and disto-buccal aspects of the 1st molars and the incisors. Based on the clinical data, 2 sites per subject were selected for subgingival plaque sampling 3 weeks later: in 32 subjects with loss of attachment > or = 1 mm, a diseased site (D) and a healthy comparison control site (C) were sampled; in 15 subjects in whom loss of attachment had not yet developed, 1 of the upper molar sites was selected, called the at-risk site (R), together with a C site. The presence and levels of A. actinomycetemcomitans, P. gingivalis, and P. intermedia were determined using an ELISA. The loss of attachment subgroup had significantly more pockets > or = 4 mm, subgingival calculus and bleeding on probing (p < 0.05). Significantly more of the D than C sites had P. gingivalis both at detectable and at measurable levels (p < 0.05). In subjects who had no loss in clinical attachment levels, fewer sampled sites harboured any of the suspected periodontopathogens investigated, and no significant differences were found between the R or C sites (p > 0.05). Although there was a significantly higher prevalence and extent of loss of attachment > or = 1 mm in the Indo-Pakistani subjects compared with the Caucasians (p < 0.05), no differences could be identified in the distribution of the bacteria. It is concluded that monitoring of the subgingival plaque may be useful in studies of early periodontitis in adolescents, and the role of P. gingivalis needs to be elucidated in prospective longitudinal investigations. 相似文献
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LL Minich LY Tani GM Pantalos BL Bolland BK Knorr JA Hawkins 《Canadian Metallurgical Quarterly》1998,66(5):1527-1532
Secretoneurin (SN), a 33-amino acid neuropeptide, is derived from secretogranin II that is released from sensory afferent C-fibers by capsaicin. Described functions of secretoneurin include chemotaxis of monocytes and endothelial cells, and inhibition of endothelial cell proliferation. Inhibition of monocyte chemotaxis by staurosporine indicated involvement of specific signaling pathways. We have tested effects of SN, substance P (SP), and interleukin-8 (IL-8) on eosinophil migration in modified Boyden chambers including signaling mechanisms of neuropeptide and cytokine stimulation of human eosinophils. Experiments showed SN as eosinophil chemoattractant comparable in its potency to IL-8. Checkerboard analysis, usage of a specific anti-SN-antibody, and receptor desensitization experiments confirmed the chemotactic activity. Preincubation of the cells with effective concentrations of staurosporine or tyrphostin-23 showed no effect, whereas treatment with wortmannin (WTN) or 3-isobutyl-1-methylxantin (IBMX) completely blocked SN-induced migration. Additionally, experiments ruled out tyrphostin-23- and WTN-sensitive signaling pathways for SP-induced chemotaxis of eosinophils. We conclude that SN-stimulated human eosinophil chemotaxis is mediated via a unique and specific signal transduction pathway that involves activation of phosphodiesterases and WTN-sensitive enzymes, ie, phospholipase D and phosphatidylinositol-3-kinase. In contrast, we report that activation of the latter and tyrosine kinases is required for SP-induced chemotaxis of eosinophils. 相似文献
1000.
GM Fabrizi A Simonati M Morbin T Cavallaro F Taioli MD Benedetti P Edomi N Rizzuto 《Canadian Metallurgical Quarterly》1998,21(7):869-877
In a cross-sectional, clinical, and morphometric analysis we assessed the correlation between the clinical and pathological evolution of disease in 20 unrelated patients of various ages affected by Charcot-Marie-Tooth neuropathy type 1A (CMT1A) with the 17p11.2p12 (peripheral myelin protein 22, PMP22) duplication. The severity of neurologic deficits and slowing of motor conduction velocity at the median nerve did not vary significantly with the patients' age. The amount of demyelination was significantly higher below 15 years than in older age groups; in contrast, myelinated fiber and onion bulb densities were similar at all ages. The results indicate that in duplicated CMT1A, the pathological process develops early in life and progresses little during the course of the disease. Younger patients had lower g-ratio values, suggesting that the trigger of demyelination in early years could be a hypermyelination, resulting from PMP22 overexpression. Yet none of the 20 patients examined had immunohistochemical evidence of altered PMP22 expression. The early onset and development of the disorder make it difficult to detect PMP22 overdosage in nerve biopsies. 相似文献