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1.
This is a study of the differences in the risk factors for being either hepatitis B surface antigen positive [HBsAg(+)] or antibody to hepatitis C virus positive [Anti-HCV(+)] in A-Lein, a rural area in southern Taiwan, an area which also has a high hepatoma mortality rate. Three hundred eighty-five patients age > or =40 years participated in hepatoma screening at the A-Lein Community Health Center during 1995. Those who were HBsAg(-) and anti-HCV(-) or had coinfection of HBsAg(+) and anti-HCV(+) were excluded, leaving 293 patients: 109 HBsAg(+) and 184 anti-HCV(+). The anti-HCV(+) patients had a lower socioeconomic status (as defined by level of education and type of occupation) and were older than HBsAg(+) patients (P < 0.05). Those with higher alanine aminotransferase levels (ALT) also had a higher anti-HCV(+) to HBsAg(+) odds ratio (OR), and a dose response relationship was found, P < 0.0001. Anti-HCV(+) patients were more likely than HBsAg(+) patients to have a spouse who shared the infection, OR = 5.11; 95% CI, 2.30-11.28. Anti-HCV(+) patients were more likely than HBsAg(+) patients to have had blood transfusions (OR = 2.66; 95% CI, 1.20-5.89), frequent medical injections (OR = 2.64; 95% CI, 1.62-4.31), or injections by non-licensed medical providers (OR = 1.91; 95% CI, 1.18-3.09). Multiple logistic regression analysis showed that the significant factors for anti-HCV(+) patients vs. HBsAg(+) patients are drinking habit (OR = 3.45; 95% CI, 1.02-11.60), age (OR = 6.33; 95% CI, 2.93-13.68), and frequent medical injections (OR = 2.88; 95% CI, 1.65-5.03). The transmission of hepatitis C in A-Lein is closely related to low socioeconomic status, age, alcohol abuse, spouses being anti-HCV(+), and frequent medical injections, especially from non-licensed medical providers, including both pharmacists and those with no medical licensing whatsoever. These nonlicensed medical providers sometimes reuse needles to save money, which is a likely route of infection. 相似文献
2.
Polarization dependent gain in erbium-doped fiber amplifiers:computer model and approximate formulas 总被引:3,自引:0,他引:3
A computer model for polarization dependent gain (PDG) in Er-doped fiber amplifiers (EDFA) is presented. The model assumes that each erbium ion possesses an ellipsoidal gain surface and that all ion orientations are equally likely. By dividing the ions into subsets based upon orientation and computing the inversion of each subset in the presence of polarized pump and signal waves, the model predicts the dependence of the PDG induced by this polarization hole-burning (PHB) on the design of the EDFA, the signal degree and state of polarization (SOP), and the pump SOP. For moderate gain amplifiers (made from the same fiber) with the same gain peak wavelength and the same compression level, the magnitude of the PDG is nearly independent of the EDFA gain. Internal and random fiber birefringence are included to model real fibers. In fibers which cause the signal SOP to walk rapidly around the Poincare sphere, the PDG is reduced by a factor of 2/3 when compared with a linear polarization-maintained signal. Scrambled signals and partially-polarized saturating tones are also considered. Simple rules are derived for predicting the PDG of a given EDFA 相似文献
3.
“万村千乡”市场工程是国家商务部计划从2005年起,力争用3年时间,在试点区域培育出约25万家农家店,形成以城区店为龙头、乡镇店为骨干、村级店为基础的农村消费经营网络,逐步缩小城乡消费差距的利民工程。 相似文献
4.
1月25日,我省实施工业强省战略企业负责人会议上,传递出一个明确的信号:全面贯彻“坚持科学发展、构建和谐四川”的一项重要任务,就是“推进工业大省向工业强省跨越”。“强省”、“跨越”,意味着“十一五”期间,工业要毫不犹豫地承担起支撑发展的重任,未来的四川工业,要在国内外市场提升地位和影响力! 相似文献
5.
Augmentation mammaplasty by the transaxillary approach seems to be a safe and anatomically sound procedure which produces consistent results with a low complication rate. Our experiences with this procedure and our modifications in the technique are described. Two instruments which were designed to facilitate the procedure are reported. An anatomical justification for the transaxillary method is made. 相似文献
6.
Rheumatoid arthritis (RA) is the most commonly occurring chronic inflammatory arthritis, the exact mechanism of which is not fully understood. Tumor Necrosis Factor (TNF)-targeting drugs has been shown to exert high effectiveness for RA, which indicates the key importance of this cytokine in this disease. Nevertheless, the response to TNF inhibitors varies, and approximately one third of RA patients are non-responders, which is explained by the influence of genetic factors. Knowledge in the field of pharmacogenomics of anti-TNF drugs is growing, but has not been applied in the clinical practice so far. Different genome-wide association studies identified a few single nucleotide polymorphisms associated with anti-TNF treatment response, which largely map genes involved in T cell function. Studies of the gene expression profile of RA patients have also indicated specific gene signatures that may be useful to develop novel prognostic tools. In this article, we discuss the significance of TNF in RA and present the current knowledge in pharmacogenomics related to anti-TNF treatment response. 相似文献
7.
Ireneusz Litwin Seweryn Mucha Ewa Pilarczyk Robert Wysocki Ewa Maciaszczyk-Dziubinska 《International journal of molecular sciences》2021,22(9)
Antimony is a toxic metalloid with poorly understood mechanisms of toxicity and uncertain carcinogenic properties. By using a combination of genetic, biochemical and DNA damage assays, we investigated the genotoxic potential of trivalent antimony in the model organism Saccharomyces cerevisiae. We found that low doses of Sb(III) generate various forms of DNA damage including replication and topoisomerase I-dependent DNA lesions as well as oxidative stress and replication-independent DNA breaks accompanied by activation of DNA damage checkpoints and formation of recombination repair centers. At higher concentrations of Sb(III), moderately increased oxidative DNA damage is also observed. Consistently, base excision, DNA damage tolerance and homologous recombination repair pathways contribute to Sb(III) tolerance. In addition, we provided evidence suggesting that Sb(III) causes telomere dysfunction. Finally, we showed that Sb(III) negatively effects repair of double-strand DNA breaks and distorts actin and microtubule cytoskeleton. In sum, our results indicate that Sb(III) exhibits a significant genotoxic activity in budding yeast. 相似文献
8.
As an approach to a general theory of olfaction, different specific anosmia phenotypes characterized by different profiles of odorant sensitivities have been proposed for humans. In the present experiments, male inbred mice were tested for relative odorant sensitivity using a conditioned aversion technique and odors classified as primary or complex for humans. C57BL/6J and C57BL/10J mice appeared to be less sensitive to the primary odorant isovaleric acid than were males of seven other inbred strains (A/J, AKR/J, BALB/cJ,C3HeB/FeJ, DBA/2J, SJL/J, and SWR/J). In comparisons of C57BL/6J and AKR/J strains, the relative insensitivity of C57 to isovaleric acid did not generalize to the musklike primary odor of pentadecalactone or to the complex odor of amyl acetate. The C57BL/6J genotype may provide an animal model of a specific anosmia as characterized among humans. 相似文献
9.
10.
Multipath degradation is a significant consideration for all wireless communication systems. A time-reversed UWB system harnesses the multipath channel to achieve temporal and spatial focusing through signal pre-filtering at the transmitter side. In cases where the RMS delay spread of a channel is larger than a user’s transmitted pulse separation, inter-pulse, -frame, and -symbol interference may occur. Of even more concern is multi-user interference, which significantly reduces system performance. This paper presents closed-form expressions for self and multi-user interference for a UWB system utilizing a time-reversed approach. The influence of user multiplexing codes is taken to account through incorporation of a ‘separation probability’, which characterizes a family of hopping sequences. The standardized IEEE 802.15.3a channel model is applied, and the derived performances are compared with that of a simulated time hopped time-reversed UWB system. 相似文献