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131.
132.
A large bibliographic survey provided data on Trypanosoma cruzi serology covering the period 1948-1984. Epidemiological-demographic methods provided an estimate of 11% for the prevalence of positive serology in Brazil, by 1984. Significant temporal trends were observed for most of the Brazilian geographical regions as well as for Brazil, as a whole. The parabolic curve that fit best for the entire country, indicates that by 1991, the incidence of new positive serology would be close to zero. This conclusion needs further fine-adjustment, since the forecast point is somewhat distant from the measured period. 相似文献
133.
Despite the widespread agreement that low-fat milk should not be used during infancy, there is a sizable portion of infants in the United States who were fed a diet that included low-fat milk (less than or equal to 2% fat). In 1985, 14% of infants 8 months old, 20% of infants 10 months old, and 32% of infants 12 months old were fed low-fat milk. The reasons given most often by mothers for low-fat milk use was their consideration that low-fat milk has less fat than whole cow's milk and that low-fat milk use was recommended/suggested by their physician. Nutrient intakes of infants fed low-fat milk are compared to those of infants fed whole cow's milk and infant formula. Except for fat, nutrient intakes of infants fed low-fat milk or whole cow's milk were similar. A majority of infants fed either low-fat milk or whole cow's milk received amounts of sodium, potassium, and chloride that exceeded the recommended safe and adequate ranges and amounts of iron below the RDA. These data are considered in relation to dietary requirements during infancy. 相似文献
134.
135.
Statistical validation of the mammaglobin-nested RT-PCR assay for tumor cell detection in blood of breast cancer patients. 总被引:3,自引:0,他引:3
A stochastic model was developed to validate the results obtained with the mammaglobin-nested RT-PCR assay for tumor cell detection in peripheral blood of breast cancer patients. Since the assay consists of four PCR setups per peripheral blood sample, the probabilities for receiving 0, 1, 2, 3, or 4 positive setups were calculated. In this model, samples with just 500 mammaglobin mRNA molecules are highly probable to result in at least three positive setups, whereas lower quantities shift the probabilities towards one or two positive setups. In the clinical trial, samples with one or two mammaglobin positive setups were detected in 6/143 (4%) patients with benign lesions of the breast, in 41/310 (13%) breast cancer patients with no evidence of disease and in 39/157 (25%) breast cancer patients with metastatic disease. On the contrary, no sample from patients with benign lesions of the breast resulted in three or four positive setups, but 5/310 (2%) breast cancer patients with no evidence of disease and 46/157 (29%) with metastatic disease. These results correspond with the model: an increased number of tumor cells in peripheral blood lead to a higher amount of mammaglobin mRNA molecules, and these samples may result in at least three positive setups. Samples with three orfour positive setups were mainly derived from breast cancer patients with metastatic disease and only occasionally from patients with no evidence of disease. On account of these results, samples with at least three positive setups are of prognostic value and regarded as tumor cell positive. 相似文献
136.
Biphasic inhibition and stimulation of microsomal oxidase activity in tissue homogenates in vitro and of dihydroisodrin (DHI) hydroxylation in vivo in black cutworm Agrotis ypsilon larvae have been produced by pretreating larvae with piperonyl butoxide (PB). Gut homogenate had greatest DHI hydroxylase activity of tissues tested and PB molar I50 was 6.4 × 10?5M. Two hours after topical application of PB (1.4 mg/larva) DHI hydroxylase was reduced 39, 30, 19 and 48% in fat body, gut, head and Malpighian tubule homogenates, and after 15 hours activity was increased 145, 69, 28 and 97% in the respective homogenates. The effects are time- and dose-dependent. In vivo three hours after PB administration, the rate of DHI hydroxylation was reduced 26%, but 15 hours after pretreatment the rate was increased 25%. 相似文献
137.
George Krieger 《The Western journal of medicine》1967,107(2):153-155
The usual surveys of completed suicides, encompassing, as they do, large geographical areas, are of limited value to physicians of a particular community. The unique and differentiating characteristics of the suicides in his locale may be “washed out” in these large surveys.San Mateo County has an annual suicide rate of 17 per 100,000 and a disproportionately high incidence in persons over 65 years old. In this particular county females, widows and Orientals are more prone to suicide than has usually been reported elsewhere. Alcohol was directly or indirectly involved in a significant number of instances. Many of the persons who killed themselves were under a physician''s care at the time of self-destruction.There are probably important ecological and sociological variables as well as personal factors involved in the suicidal process that are of significance to any suicide prevention program. It is urged that there be more extensive and comparative research in this important public health problem. 相似文献
138.
139.
Magda Grabsztunowicz Paula Mulo Frauke Baymann Risa Mutoh Genji Kurisu Pierre Stif Peter Beyer Anja Krieger‐Liszkay 《The Plant journal : for cell and molecular biology》2019,99(2):245-256
During daffodil flower development, chloroplasts differentiate into photosynthetically inactive chromoplasts having lost functional photosynthetic reaction centers. Chromoplasts exhibit a respiratory activity reducing oxygen to water and generating ATP. Immunoblots revealed the presence of the plastid terminal oxidase (PTOX), the NAD(P)H dehydrogenase (NDH) complex, the cytochrome b6f complex, ATP synthase and several isoforms of ferredoxin‐NADP+ oxidoreductase (FNR), and ferredoxin (Fd). Fluorescence spectroscopy allowed the detection of chlorophyll a in the cytochrome b6f complex. Here we characterize the electron transport pathway of chromorespiration by using specific inhibitors for the NDH complex, the cytochrome b6f complex, FNR and redox‐inactive Fd in which the iron was replaced by gallium. Our data suggest an electron flow via two separate pathways, both reducing plastoquinone (PQ) and using PTOX as oxidase. The first oxidizes NADPH via FNR, Fd and cytochrome bh of the cytochrome b6f complex, and does not result in the pumping of protons across the membrane. In the second, electron transport takes place via the NDH complex using both NADH and NADPH as electron donor. FNR and Fd are not involved in this pathway. The NDH complex is responsible for the generation of the proton gradient. We propose a model for chromorespiration that may also be relevant for the understanding of chlororespiration and for the characterization of the electron input from Fd to the cytochrome b6f complex during cyclic electron transport in chloroplasts. 相似文献
140.
Bernardo R Tura Helena F Martino Luis H Gowdak Ricardo Ribeiro dos Santos Hans F Dohmann José E Krieger Gilson Feitosa Fábio Vilas-Boas Sérgio A Oliveira Suzana A Silva Augusto Z Bozza Radovan Borojevic Antonio C Campos de Carvalho 《Trials》2007,8(1):1-4