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801.
Col James H. Nelson Col Carl E. Stracener Constance Gannon 《The Western journal of medicine》1978,129(3):243-249
A child health assessment and screening program, staffed by volunteers, has evaluated approximately 5,000 children in a general pediatric clinic. A sample of 500 children was studied to determine characteristics of the population served, quality of the work of the volunteers and the number of new problems identified. Use of well-trained volunteers, provided with adequate supervision and follow-up physical examination of the children, identified many new problems at minimal cost and proved an effective means of expanding quality health care. 相似文献
802.
In experiments with one freshwater (Chlorella pyrenoidosa) and three marine organisms (Phaeodactylum tricornutum, Cyclotella nana, and Chaetoceros galvestonensis), mecury was more toxic than the other metals tested (silver, cadmium, lead, and copper); and its toxicity is comparatively irreversible. Growth was monitored by changes in fluorescence of the cultures over a 3-day test period. The toxicity of the mercury varied inversely with the concentrations of nutrients present. Preliminary experiments indicate that mercury in the form of mercuric chloride is more than as dimethylmercury. 相似文献
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805.
Eiri Heyno Christine M. Gross Constance Laureau Marcel Culcasi Sylvia Pietri Anja Krieger-Liszkay 《The Journal of biological chemistry》2009,284(45):31174-31180
Photoinhibition and production of reactive oxygen species were studied in tobacco plants overexpressing the plastid terminal oxidase (PTOX). In high light, these plants was more susceptible to photoinhibition than wild-type plants. Also oxygen-evolving activity of isolated thylakoid membranes from the PTOX-overexpressing plants was more strongly inhibited in high light than in thylakoids from wild-type plants. In contrast in low light, in the PTOX overexpressor, the thylakoids were protected against photoinhibition while in wild type they were significantly damaged. The production of superoxide and hydroxyl radicals was shown by EPR spin-trapping techniques in the different samples. Superoxide and hydroxyl radical production was stimulated in the overexpressor. Two-thirds of the superoxide production was maintained in the presence of DNP-INT, an inhibitor of the cytochrome b6f complex. No increase of the SOD content was observed in the overexpressor compared with the wild type. We propose that superoxide is produced by PTOX in a side reaction and that PTOX can only act as a safety valve under stress conditions when the generated superoxide is detoxified by an efficient antioxidant system. 相似文献
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807.
The precise, quantitative portrayal of intraindividual change is a key goal of developmental researchers. Research designs particularly appropriate to selected aspects of this goal are multivariate, replicated, single-subject, repeated measures (MRSRM) designs. Data collected with these designs may be factor analyzed with P-technique factor analysis to elucidate, for each individual studied, patterns of systematic change. The nature of the factor patterns obtained for each individual can then be compared across individuals to determine the relative idiosyncrasy or generality of patterns of change. This paper extends an earlier review (Luborsky & Mintz, 1972) of studies using multivariate, single-subject, repeated measures designs and P-technique factor analysis. The emphasis here is on both more recent studies and the value of subject replication in creating a confluence of idiographic and nomothetic approaches to the study of behavior and behavioral development across the lifespan. 相似文献