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991.
992.
PJ Adams A Powell R McCormick G Paton-Simpson 《Canadian Metallurgical Quarterly》1997,110(1049):291-294
AIMS: To assess current practices and attitudes of general practitioners towards prevention and intervention with problem drinkers. METHODS: GPs randomly selected in the Central and Southern Health Regions answered a 134 item questionnaire on their involvement with patients with alcohol related problems. RESULTS: In all, 136 general practitioners responded representing 85% of those approached. When asked how often they provided interventions with alcohol problems, 86% reported managing under 13 patients per year, indicating an intervention rate of less than 1% of the mean practice size. In terms of disease prevention, 86% rated 'drinking moderately' as important but this endorsement ranked fifth behind other lifestyle behaviours such as 'not smoking' at 99%. When asked about their perceived role, they indicated higher role legitimacy but lower work satisfaction with alcohol problems. In terms of training, three-quarters stated they had received less than eleven hours of postgraduate alcohol education. They also rated their current effectiveness with alcohol problems as substantially less than potential effectiveness. They indicated the main obstacles to be: government funding policies, lack of adequate training and a need for improved resources and support services. CONCLUSIONS: With research having established the effectiveness of interventions for harmful alcohol consumption, attention has shifted to ways of engaging general practitioners in providing interventions. This study highlighted how changes to government health policy and improved competency and skilled based training could lead to a greater acceptance by general practitioners of the role they could play in reducing alcohol related problems. 相似文献
993.
We report a case of primary malignant fibrous histiocytoma of spleen, which also emphasizes the difficulties in diagnosing such a rare condition. 相似文献
994.
RB Yang MR Mark A Gray A Huang MH Xie M Zhang A Goddard WI Wood AL Gurney PJ Godowski 《Canadian Metallurgical Quarterly》1998,395(6699):284-288
Vertebrates and invertebrates initiate a series of defence mechanisms following infection by Gram-negative bacteria by sensing the presence of lipopolysaccharide (LPS), a major component of the cell wall of the invading pathogen. In humans, monocytes and macrophages respond to LPS by inducing the expression of cytokines, cell-adhesion proteins, and enzymes involved in the production of small proinflammatory mediators. Under pathophysiological conditions, LPS exposure can lead to an often fatal syndrome known as septic shock. Sensitive responses of myeloid cells to LPS require a plasma protein called LPS-binding protein and the glycosylphosphatidylinositol-anchored membrane protein CD14. However, the mechanism by which the LPS signal is transduced across the plasma membrane remains unknown. Here we show that Toll-like receptor 2 (TLR2) is a signalling receptor that is activated by LPS in a response that depends on LPS-binding protein and is enhanced by CD14. A region in the intracellular domain of TLR2 with homology to a portion of the interleukin (IL)-1 receptor that is implicated in the activation of the IL-1-receptor-associated kinase is required for this response. Our results indicate that TLR2 is a direct mediator of signalling by LPS. 相似文献
995.
PJ Ala EE Huston RM Klabe PK Jadhav PY Lam CH Chang 《Canadian Metallurgical Quarterly》1998,37(43):15042-15049
The long-term therapeutic benefit of HIV antiretroviral therapy is still threatened by drug-resistant variants. Mutations in the S1 subsite of the protease are the primary cause for the loss of sensitivity toward many HIV protease inhibitors, including our first-generation cyclic urea-based inhibitors DMP323 and DMP450. We now report the structures of the three active-site mutant proteases V82F, I84V, and V82F/I84V in complex with XV638 and SD146, two P2 analogues of DMP323 that are 8-fold more potent against the wild type and are able to inhibit a broad panel of drug-resistant variants [Jadhav, P. K., et al. (1997) J. Med. Chem. 40, 181-191]. The increased efficacy of XV638 and SD146 is due primarily to an increase in P2-S2 interactions: 30-40% more van der Waals contacts and two to four additional hydrogen bonds. Furthermore, because these new interactions do not perturb other subsites in the protease, it appears that the large complementary surface areas of their P2 substituents compensate for the loss of P1-S1 interactions and reduce the probability of selecting for drug-resistant variants. 相似文献
996.
PJ Brits 《Canadian Metallurgical Quarterly》1997,87(11):1552-1553
997.
OBJECTIVE: The objective of the study was to compare the accuracy of the TDxFLM test (Abbott Laboratories) with the fetal lung maturity cascade (shake, foam stability index, lecithin/sphingomyelin tests) and to determine whether the TDxFLM test could increase the efficiency and reduce the cost without decreasing the reliability of a cascade. STUDY DESIGN: A prospective, single-blinded study was conducted. Uncontaminated amniotic fluid obtained by transabdominal amniocentesis for fetal lung maturity assessment was evaluated with use of the fetal lung maturity cascade and the TDxFLM test. At study completion the results of the TDxFLM test were compared with those of the maturity cascade with regard to hyaline membrane disease, which was defined by strict clinical and radiographic parameters. A power analysis was performed requiring a sample size of 100 infants delivered within 72 hours of amniocentesis with use of the 95% confidence interval. RESULTS: A total of 115 cases had a full maturity cascade performed, of which 40 (35%) had a positive shake or foam stability index and 75 cases required progression to a lecithin/sphingomyelin ratio because of negative results. The TDxFLM test result was > or = 70 mg/gm in 42 (37%) of these 115. One hundred eight newborns were delivered within 72 hours of the amniocentesis; 65% (71) of these were between 30 and 37 weeks of estimated gestational age. There were 7 cases of hyaline membrane disease in the 108 newborns. Of these 108, 87 had a mature original cascade versus 85 mature tests with use of a proposed TDxFLM test-lecithin/sphingomyelin ratio cascade with one case of respiratory distress syndrome and hyaline membrane disease. The sensitivity, specificity, and positive and negative predictive values for the original cascade were 86%, 84%, 27%, and 99%, respectively; for the proposed TDxFLM test-lecithin/sphingomyelin ratio cascade the values were 86%, 83%, 26%, and 99%, respectively. The TDxFLM test-lecithin/sphingomyelin ratio cascade would have resulted in a cost reduction of 24% with no significant delay in turnaround time. CONCLUSION: The TDxFLM test appears to be a reliable and accurate assessment of fetal lung maturity. Furthermore, by replacing the shake and foam stability index portion of the cascade with the TDxFLM test, a cost savings of 24% would occur without a decrease in safety. These results also reveal that it could enhance patient care and be cost efficient for institutions not currently doing fetal pulmonary maturity testing to undertake use of the TDxFLM test and to only send out specimens for a lecithin/sphingomyelin ratio that have an initial immature TDxFLM test result (< 70 mg/gm). Likewise, institutions currently only performing a lecithin/sphingomyelin ratio may consider a TDxFLM test-lecithin sphingomyelin ratio cascade. Although direct costs would increase, they would be counterbalanced by a significant reduction in laboratory technician time. 相似文献
998.
The authors carried out research on breast volume and body surface anatomy of 125 women. As a result, an average breast volume for Chinese women was obtained (325.36 +/- 12.66 ml), and a table with several linear equations for calculating breast volume was derived. The authors applied these results to their clinical work and succeeded in making mammaplasty more precise in 178 patients. 相似文献
999.
1000.
Treatment of isolated DNA with crocidolite and man-made vitreous fibre-21 (MMVF-21) significantly increased the concentration of 8-hydroxydeoxyguanosine (8-OHdG) in isolated DNA above background levels and co-treatment with glutathione (GSH) eliminated this effect. Crocidolite, MMVF-21 and chrysotile fibres increased the number of revertants in Salmonella typhimurium TA100 and GSH-deficient strains, TA100/NG-54 and TA100/NG-57, over background levels. This increase was small in TA100 but was greater in the GSH-deficient strains. When these bacterial strains were further depleted of GSH by co-culture with buthionine sulfoximine, all fibres tested caused a significant increase in the number of revertants over the parent strains. Pre-treatment with the GSH precursor N-acetyl-L-cysteine reduced the number of revertants to below that of the parent strain. Previous studies have shown a mechanistic role for iron-catalyzed production of oxygen radicals in the mutagenicity of fibres and this study suggests a protective role for GSH against such oxidative damage possibly by acting as a radical scavenger. 相似文献