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91.
Zaim M Ghavami MB Nazari M Edrissian GH Nateghpour M 《Journal of the American Mosquito Control Association》1998,14(4):421-430
In a study carried out in the Ghassreghand Division (Baluchistan, Iran) from March through November 1995, efficacy of cyfluthrin-impregnated bednets was compared to that of untreated nets, in relation to malaria control. Ten villages with a total population of 4,572 and 3 villages with a total population of 1,935 were used as treatment and control, respectively. The collection, impregnation (target dosage of 40 mg active ingredient [AI]/m2), and redistribution of the nets (9% nylon, 52% light cotton, 30% medium cotton, and 9% heavy cotton), carried out in mid-April, were done by local health workers, supervised by the senior research staff. Anopheles culicifacies was considered to be the main vector of malaria in the named area. This species is mainly zoophilic, endophilic, and exophagic. The initial uptake of the insecticide was lower than the target dosage, with high variation (nylon, 12.5 +/- 5.4 mg AI/m2; light cotton, 33.3 +/- 26.1 mg AI/m2; medium cotton, 25.9 +/- 20 mg AI/m2; heavy cotton, 17.6 +/- 12.5 mg AI/m2). The use of impregnated mosquito nets (used primarily outside) had no significant effect on the incidence of malaria. No difference was detected in the parasite density of patients with positive slides. No significant effect was observed in the parous rate, human blood index, and sporozoite rate of anopheline vectors. Only the indoor resting densities of An. culicifacies and other malaria vectors were drastically reduced after the introduction of the cyfluthrin-impregnated nets into the treatment villages. The residual activity of cyfluthrin was lower than expected. The mortality of anophelines brought in contact with the treated nets for 3 min in bioassays dropped to less than 55% in 3 months. The loss of chemical activity was greatest for the light cotton nets, followed by the medium cotton nets. Cyfluthrin-treated nets were mildly irritating to host-seeking female anophelines in the laboratory. The protective rate of impregnation (all fabric kinds included) in preventing female mosquitoes from biting through the impregnated nets was initially 5-6 times that of the nonimpregnated nets. The study did not detect any significant difference between the use of untreated versus impregnated bednets in the Ghassreghand area. In planning future medium-scale trials, comparison of new compounds and formulations to the more widely used pyrethroids such as permethrin and deltamethrin is highly recommended. 相似文献
92.
Boivin G Côté S Cloutier N Abed Y Maguigad M Routy JP 《Journal of medical virology》2002,68(3):399-403
Few studies have assessed human herpesvirus 8 (HHV8) viremia levels in different HHV8-related pathologies, using sensitive and reproducible molecular assays. Our objective was to compare the HHV8 DNA load in serial blood samples (collected every 3 months for 1 year) from acquired immunodeficiency syndrome (AIDS) patients with Kaposi's sarcoma (KS) and multicentric Castleman's disease (MCD). The HHV8 viral load was determined in both peripheral blood mononuclear cells (PBMC) and plasma fractions, using a competitive real-time polymerase chain reaction (PCR) assay developed in a LightCycler instrument (Roche Diagnostics). In six subjects with limited or extensive KS while on highly active antiretroviral therapy, the HHV8 DNA load was either undetectable (<50 copies/10(5) cells) or low (=135 copies) in all PBMC samples. In contrast, the cellular HHV8 load was >1,000 copies in at least one of the samples from the two subjects with both KS and MCD. HHV8 DNA was detected in plasma only when the cellular viral load was >10,000 copies/10(5) cells. After chemotherapy, the HHV8 DNA load became undetectable in the MCD patients despite no changes in CD4 T-cell counts or highly active antiretroviral therapy (HAART) regimens. These results suggest that the pathogenesis of the two HHV8-associated diseases (i.e., KS and MCD) might be different, as only the latter was associated with important viremia in our patients. 相似文献
93.
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95.
Activity of the neuraminidase inhibitor A-315675 against oseltamivir-resistant influenza neuraminidases of N1 and N2 subtypes 总被引:2,自引:1,他引:1
Clinical use of the neuraminidase inhibitor (NAI) oseltamivir has been associated with the emergence of viral resistance resulting from subtype-specific neuraminidase (NA) mutations. In this study, we evaluated the impact of the most frequent oseltamivir-resistant NA mutations including E119V, H274Y, R292K and N294S on the susceptibility profile to a novel NAI (A-315675) using recombinant NA proteins of N1 and N2 subtypes and also selected oseltamivir-resistant influenza H1N1 and H3N2 viruses. In the N1 subtype, recombinant NA proteins containing mutations H274Y and N294S previously associated with resistance to oseltamivir (754- and 197-fold increases in IC(50) values, respectively, compared to WT) remained susceptible to A-315675 (2.5- and 2-fold increases in IC(50) values(,) respectively). In the N2 subtype, NA proteins harboring mutations E119V and R292K conferring high levels of resistance to oseltamivir (1016- and >10,000-fold increases in IC(50) values, respectively) had IC(50) values that increased by only 1.5- and 13-fold, respectively, against A-315675. Similar susceptibility patterns to A-315675 were obtained when testing recombinant H1N1 mutant viruses (H274Y and N294S) and clinical H3N2 mutants (E119V). The V116A and I117V mutations, previously associated with oseltamivir resistance in H5N1 viruses, were susceptible to oseltamivir when tested in the H1N1 background suggesting a strain-specific impact of these mutations. These results confirm the potent inhibitory effect of A-315675 against oseltamivir-resistant influenza viruses of the N1 and N2 subtypes and support the clinical development of its bioavailable prodrug A-322278. 相似文献
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97.
The research reported in this paper aims to evaluate the epoxy injection technique used to strengthen fiber-reinforced self-compacting concrete (FRSCC) with high strength. This method is carried out on ruptured concrete specimens to assess the efficiency of the epoxy resin adhesive injection retrofitting technique for strength and stiffness. Five FRSCC mixes were designed and placed using different types (steel and polypropylene) and contents (0%, 0.25%, and 0.45% by volume) of fibers. The fresh and mechanical properties in addition to the microstructure of produced mixes were evaluated to assess the impact of fibers on the behavior of FRSCC. Results showed that the workability of FRSCC is reduced by increasing steel or polypropylene fiber content; however, the rheological characteristics of placed mixes satisfied the European Guidelines for Self-Compacting Concrete recommendation for fresh concrete. Also, splitting tensile, flexural, and shear strengths were enhanced by increasing fiber content. The simultaneous application of epoxy injection in FRSCC for repairing damaged concrete beams was shown to be highly effective. 相似文献
98.
ObjectivesTo evaluate and compare perceived pain and jaw function impairment during the first 4 weeks with slow maxillary expansion (SME) using quadhelix and rapid maxillary expansion (RME) using conventional banded hyrax.Materials and MethodsSixty patients aged 10.2 to 15 years were enrolled and consecutively recruited to either the quadhelix group (QG) or hyrax group (HG). A questionnaire was used to evaluate pain, jaw function impairment, and analgesic consumption in the first 7 days, at 2 weeks, and at 4 weeks.ResultsFifty-five patients (43 girls and 12 boys) completed the questionnaire at all time points (27 in the QG and 28 in the HG). Except at 4 hours, there were no significant differences between the groups regarding pain from teeth, tongue, and palate. Patients started to adapt after day 3. Patients in the HG group reported significantly higher scores for difficulty in swallowing (moderate to severe) during the first 6 days. In both groups, minimal effects were found on speech and the majority of patients did not experience difficulty in yawning or laughing. There was no significant difference in analgesic consumption between the groups. No correlations were found between age, gender, or malocclusion type and any of the investigated outcomes.ConclusionsQuadhelix for SME and conventional banded hyrax for RME were well tolerated by patients after 1 week. The decision to use either appliance could be based on factors not related to patient experiences. 相似文献
99.
Dmitry Olegovich Bokov Mohammed Abed Jawad Wanich Suksatan Mahmoud E. Abdullah Aleksandra
wierczyska Dariusz Fydrych Hamed Aghajani Derazkola 《Materials》2021,14(24)
This article studied the effects of pin angle on heat generation and temperature distribution during friction stir welding (FSW) of AA1100 aluminum alloy and St-14 low carbon steel. A validated computational fluid dynamics (CFD) model was implemented to simulate the FSW process. Scanning electron microscopy (SEM) was employed in order to investigate internal materials’ flow. Simulation results revealed that the mechanical work on the joint line increased with the pin angle and larger stir zone forms. The simulation results show that in the angled pin tool, more than 26% of the total heat is produced by the pin. Meanwhile, in other cases, the total heat produced by the pin was near 15% of the total generated heat. The thermo-mechanical cycle in the steel zone increased, and consequently, mechanical interlock between base metals increased. The simulation output demonstrated that the frictional heat generation with a tool without a pin angle is higher than an angled pin. The calculation result also shows that the maximum heat was generated on the steel side. 相似文献
100.
Sajjad Moradi Hamed Mohammadi Abed Ghavami Mohammad Hossein Rouhani 《Journal of the American Society of Hypertension》2018,12(12):822-832
Emerging evidence suggested that large neck circumference (NC) in children and adolescents may be an indicator of increased blood pressure. We sought to conduct a systematic review and meta-analysis regarding the association between NC and blood pressure in children. Pertinent studies were identified by searching PubMed and Scopus databases, up to January 2018. Studies which reported the correlation coefficient between NC, systolic blood pressure and diastolic blood pressure in children (aged <18 years) were selected. Fifteen studies met eligibility criteria for the quantitative synthesis. Overall, NC was significantly correlated with systolic blood pressure (effect size (z) = 0.39; 95% confidence interval [CI] = 0.29–0.49; P < .001; meta r = 0.371; r2 = 0.13) and diastolic blood pressure (effect size (z) = 0.25; 95% CI = 0.19–0.32; P < .001; meta r = 0.0.245; r2 = 0.06). NC had a positive relationship with the risk of hypertension (odds ratio [OR] = 1.35; 95% CI: 1.05–1.75). Furthermore, studies conducted in Western regions (OR = 1.55; 95% CI: 1.12–2.14) reported higher risk of hypertension in association with NC than those conducted in the Eastern regions (OR = 1.14; 95% CI: 1.03–1.25).NC seems to be a novel anthropometric measurement in children and adolescents. It can be a good predictor of elevated blood pressure, especially in the Western population. 相似文献