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1.
Cyclic peptide disulfides of the general formula were synthesized from the corresponding peptide derivatives [Boc-Cys(Trt)(Gly)-n-Cys(Trt)-OBut] by oxidation with iodine in methanol and by subsequent removal of the terminal groups with trifluoroacetic acid. Acid ionization constants of the obtained peptides were determined by potentiometric titration in aqueous KCl (0.1 mol/L) medium. All compounds have two dissociable hydrogens, corresponding to carboxyl (pK1= 2.35–2.84) and to terminal amino group (pK2= 5.61–6.93); pK1, values show first an upward and then a downward trend with the increase in ring size; the opposite is true for pK2, values. These trends could be tentatively attributed to the intramolecular salt bridge (-COO——-NH+3-) formation.  相似文献   
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The laboratory verified cases of Crimean-Congo hemorrhagic fever (CCHF) in the piedmont steppes of the North Caucasus (Malgobeksky District, Republic of Ingushetia) are first described. The source of the first infection was Ixodidae ticks; three subsequent sources were contacts with the bloody discharges from patients. CCHF virus genome was detected in the blood of the cattle from an epidemic focus and in the pools of the Ixodes ticks Haemaphysalis parva Neum., 1897 and Boophilus annulatus Say, 1821, taken from cattle. The problem of including the piedmont steppes of the North Caucasus into the CCHF nosological area is discussed.  相似文献   
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Pharmaceutical Chemistry Journal - The production technology for nanoparticles based on a copolymer of lactic and glycolic acids (PLGA) containing dipropoxybacteriopurpurinimide (DPBPI) and...  相似文献   
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GTP cyclohydrolase (GCH1) is rate limiting for tetrahydrobiopterin (BH4) synthesis, where BH4 is a cofactor for nitric oxide (NO) synthases and aromatic hydroxylases. GCH1 polymorphisms are implicated in the pathophysiology of pain, but have not been investigated in African populations. We examined GCH1 and pain in sickle cell anemia where GCH1 rs8007267 was a risk factor for pain crises in discovery (n = 228; odds ratio [OR] 2.26; P = 0.009) and replication (n = 513; OR 2.23; P = 0.004) cohorts. In vitro, cells from sickle cell anemia subjects homozygous for the risk allele produced higher BH4. In vivo physiological studies of traits likely to be modulated by GCH1 showed rs8007267 is associated with altered endothelial dependent blood flow in females with SCA (8.42% of variation; P = 0.002). The GCH1 pain association is attributable to an African haplotype with where its sickle cell anemia pain association is limited to females (OR 2.69; 95% CI 1.21–5.94; P = 0.01) and has the opposite directional association described in Europeans independent of global admixture. The presence of a GCH1 haplotype with high BH4 in populations of African ancestry could explain the association of rs8007267 with sickle cell anemia pain crises. The vascular effects of GCH1 and BH4 may also have broader implications for cardiovascular disease in populations of African ancestry. Am. J. Hematol. 89:187–193, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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While insoluble nickel subsulfide (Ni3S2) was carcinogenic in the lung in a 2‐year rat bioassay, soluble nickel sulfate hexahydrate (NiSO4*6H2O) was not. To investigate whether differences in the cellular responses to these two nickel compounds could underlie their differential activities, we conducted parallel studies to determine the gene expression changes in micro‐dissected lung distal airway cells from Fischer 344 rats following inhalation of the two compounds for one and four weeks (6 hr per day, 5 days per week). The results of the Ni3S2 study have been reported previously; this paper reports the results for NiSO4 and provides a comparative analysis. The cellular responses to NiSO4 were highly similar to those previously reported for Ni3S2, and a set of genes was identified whose expression could be used as biomarkers for comparing cellular nickel effects from in vitro or in vivo studies with soluble NiSO4 and particulate Ni3S2. Evaluation of the genomic concentration‐responses for the two compounds suggests that the highest inhaled concentration in the tumor bioassay for NiSO4, which was limited by toxicity, may not have achieved the Ni concentrations at which tumors were observed in the Ni3S2 bioassay. However, several key differences in the immune responses to NiSO4 and Ni3S2 were identified that may result from the differential intracellular disposition of Ni from NiSO4 entering the cell as an ion rather than as a slowly soluble Ni3S2 particle. These differences may also contribute to the observation of tumors in the bioassay for Ni3S2 but not NiSO4. Environ. Mol. Mutagen. 58:607–618, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society  相似文献   
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目的 :提高贫困地区壮族农村住院分娩率 ,加强产时保健 ,提高贫困地区壮族农村产科质量 ,降低产后出血死亡率。在广西 30个老少边山穷地区 ,以项目和“母亲安全工程”为载体 ,在经济条件困难 ,基础设施落后 ,围产保健服务管理滞后的情况下 ,积极贯彻落实《母婴保健法》,依法规范围产保健服务管理 ,多方筹措资金 ,加强产科软、硬件建设 ,以项目工作为龙头 ,以科研为先导 ,积极推广适宜技术。以健康促进为目的 ,大力开展健康教育和生殖保健活动 ,使围产保健工作取得了较好成绩。30个贫困地区壮族农村近半数以上乡卫生院产科建设已达自治区标准 ,基本能满足贫困地区农民住院分娩的需求 ,并带动广西妇幼卫生工作的发展  相似文献   
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