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排序方式: 共有387条查询结果,搜索用时 15 毫秒
51.
EN Smit JM Dijkstra TA Schnater E Seerat FAJ Muskiet ER Boersma 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(7):690-695
Abstract Erythrocyte fatty acids and plasma vitamin E concentrations were determined in 47 grade 2 and 21 grade 3 malnourished Pakistani children (ages 4–56 months). Data were compared with those of 26 age- and sex-matched apparently healthy controls. Evaluation with three statistical approaches revealed that both grade 2 and grade 3 malnourished children had decreased erythrocyte ω6 fatty acids and to a lesser extent decreased ω3 fatty acids. These decreases were compensated for by increased ω9 fatty acids. The patients tended to have lower plasma vitamin E concentrations. We conclude that malnourished Pakistani children have low essential fatty acid status, notably those of the ω6 series. The combination of low erythrocyte 22:6ω3 and a low 22:5ω6/22:4ω6 ratio in grade 2 patients suggests low Δ4-desaturation activity, which may be due to impaired peroxisomal β-oxidation. 相似文献
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The aim of this work was to study the influence of bacterial cell concentrations and inorganic anions on lysis of Streptococcus mutans BHT by human salivary lysozyme (HSL). HSL was partly purified from saliva by ion exchange chromatography. The bacteria were grown in a synthetic medium containing 3H-thymidine to monitor DNA release. The experiments demonstrated that release 3H-thymidine was dependent on the bacterial cell concentration and an apparent Km-value corresponding to approximately 2.9 × 108 cells/ml was calculated. The influence of I?, Br?, Cl?, F?, HCO3? and SCN? on bacteriolysis was studied. All anions tested were slightly inhibitory on the action of HSL. The inhibition varied from 7 to 76% depending on the ion and ionic strength. The order of addition of HSL and sodium chloride caused different lytic responses. This was reflected by the amount of HSL adsorbed by the bacteria. 相似文献
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MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
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Malik S, Kakar N, Hasnain S, Ahmad J, Wilcox ER, Naz S. Epidemiology of Van der Woude syndrome from mutational analyses in affected patients from Pakistan. Mutations in IRF6 cause Van der Woude syndrome (VWS), one of the most common syndromes associated with cleft lip (CL) with or without cleft palate (CP). The presence of pits on the lower lip of patients is the most characteristic feature of the syndrome. We have identified three novel and seven previously reported IRF6 mutations in 12 of 16 unrelated families segregating VWS from Pakistan. The three newly identified mutations include a frameshift (c.568delG) and two missense mutations c.295G>A (p.G99S) and c.1219T>C (p.S407P). Recent functional studies on IRF6 and the three‐dimensional structure of IRF5 carboxy (C) terminus, a protein encoded by a paralog of IRF6, shed light on the p.S407P substitution. Additionally, the identification of the same mutations responsible for VWS in Pakistan, as reported in other global populations worldwide, marks these residues as mutational hotspots and indicates their essential role in structural stability or function of IRF6. This is the first study of VWS in Pakistan and we estimate that 1 in 100 patients with CL with or without CP (CL/P) are affected in the Pakistani population predominantly from the Punjab area. 相似文献
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目的探讨新疆护理教师工作压力现状并分析其影响因素,为提出护理教师队伍建设的相关对策提供实证依据并为护理院校管理和教师人才队伍的可持续发展提出建议。方法采用高职教师工作压力量表对新疆15个地、市、州抽取的10所护理院校在编在岗的256位护理教师进行问卷调查,调查其工作压力现状并分析其影响因素。结果护理专职教师的工作压力得分为(2.436±0.576)分,大于2分,说明教师的工作压力大。教龄、婚姻、兼职情况及教学工作量不同的教师因社会因素而产生的工作压力水平不同,不同婚姻状况的教师因学校管理及制度因素产生的压力水平不同,性别、年龄、学历、婚姻、教学工作量不同的教师个人职业发展所带来的压力水平不同,性别、教龄、每周课时量等在护理院校教师工作压力不同;年龄、婚姻状况、教学工作量不同的教师因人际关系产生的工作压力水平不同,性别、年龄、教龄、职称、婚姻、教学工作量、收入水平及兼职情况不同的教师因工作负荷压力水平不同,性别、职称、婚姻、教学工作量、担任教学课程不同的教师因个人特质因素带来的工作压力不同,差异均有统计学意义(P〈0.05)。结论护理专职教师的工作压力大,来源是多方面的,学校管理制度和社会因素带来的压力最大,因此应尽快改变社会各界对护理教育认识上的不足和偏见,明确护理教育的定位,加大国家对护理教育的投入,同时护理教师应提高对自己职业的认识,合理制定自己的职业生涯发展规划。 相似文献
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