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51.
From 1974 to 1989, a total of 24,500 aborigines at 67 villages in ten mountainous districts/towns in Taiwan were examined for the Taiwan Taenia infection and 12% were found to be infected. In order to define the clinical manifestations of taeniasis caused by the Taiwan Taenia, 1661 aborigines in ten mountainous districts were surveyed. The overall clinical rate was 76%. The clinical rate was highest among Atayal aborigines (81%), followed by Bunun (66%) and Yami (61%) aborgines and lowest among Ami aborigines (40%). Among 1153 infected people, 10% had passed gravid segments in the faeces for less than 1 year, 24% for 1-3 years, 17% for 4-5 years, 23% for 6-10 years, 16% for 11-20 years, 7% for 21-30 years, and 3% over 30 years. Twenty-six occurrences of gastrointestinal and neurological symptoms were reported by 1258 infected persons. Passing proglottides in the faeces (95%) was the most frequent sign, followed by pruritis ani (77%), nausea (46%), abdominal pain (45%), dizziness (42%), increased appetite (30%), headache (26%), etc. 相似文献
52.
John W. Y. Chan Ronald S. Burton 《Evolution; international journal of organic evolution》1992,46(3):721-734
Flooding results in induction of anaerobic metabolism in many higher plants. As an important component of anaerobic energy production, alcohol dehydrogenase (ADH) activity increases markedly in response to flooding in white clover, Trifolium repens. Significant inter-individual variation in flood-induced ADH activity exists in natural populations of T. repens. The genetic basis of this variation was analyzed by offspring-midparent regression of data from 75 greenhouse reared families; the estimated heritability of flood-induced ADH activity was 0.55 (±0.13). Genetic variation in flood-induced ADH activity has pronounced effects on physiological response and flood tolerance in this species. ADH activity is positively correlated with the rate of ethanol production, indicating that observed in vitro activity differences are manifested in in vivo physiological function. T. repens plants with higher ADH activities during flooding have greater flood tolerance (measured as growth rate when flooded/unflooded growth rate). Variation in ADH activity during flooding accounts for more than 79% of the variance in flood tolerance. On the basis of a limited field survey of populations occupying three sites differing in exposure to flooding conditions, individuals from site C, the most frequently flooded site, expressed significantly higher average ADH activity when flooded than individuals from site A, a site with no history of flooding. Since ADH activity levels are not correlated with electrophoretic mobility variation in T. repens, this work supports previous suggestions that regulatory variation in enzyme activity may play a central role in biochemical adaptations to environmental stress. 相似文献
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56.
Barbara L. Brody Harold J. Simon Dennis E. Smallwood 《The Western journal of medicine》1987,147(3):350-356
Private financing for long-term care now comes almost exclusively from out-of-pocket payments. Long-term-care costs quickly impoverish most elderly, resulting in Medicaid dependency. The consequences are profound for the western Sun Belt with its rapidly growing elderly population. Key private financing options are long-term-care individual retirement accounts (LTC/IRAs), home equity conversion, social-health maintenance organizations and long-term-care insurance. Study of data from the past half century suggests that the LTC/IRA approach would prove unsatisfactory for the purpose despite the intuitive appeal of this mechanism. Experience with home equity conversions is still very limited, and unresolved questions limit this approach to the role of a reserve option for now. While promising, social-health maintenance organizations are still in the experimental stages and not yet commercially available. Long-term-care insurance is currently sold on a thin market and emphasizes nursing home coverage. New approaches to private financing through long-term-care insurance seem to offer the best approach for immediate implementation. 相似文献
57.
Big Moose Basin: simulation of response to acidic deposition 总被引:2,自引:1,他引:1
George F. Davis John J. Whipple Steven A. Gherini Carl W. Chen Robert A. Goldstein Arland H. Johannes Peter W.H Chan Ronald K. Munson 《Biogeochemistry》1987,3(1-3):141-161
The ILWAS model has been enhanced for application to multiple-lake hydrologic basins. This version of the model has been applied to the Big Moose basin, which includes Big Moose Lake and its tributary streams, lakes, and watersheds. The basin, as defined, includes an area of 96 km2, with over 20 lakes and ponds, and 70 km of streams. Hydrologic and chemical calibrations have been made using data from seven sampling stations. When total atmospheric sulfur loading to the basin is halved, the model predicts, after four years of simulation, a decreasing sulfate concentration and to a lesser extent a rising alkalinity at Big Moose Lake outlet. At the end of four years, the results show an increase in pH of 0.1 to 0.5 pH units depending upon season. 相似文献
58.
Stephen Chan James Orenberg Noam Lahav 《Origins of life and evolution of the biosphere》1987,17(2):121-134
The adsorption of 5-AMP and 5-CMP was studied in saturated solutions of several soluble mineral salts (NaCl, Na2SO4, MgCl2·6H2O, MgSO4·7H2O, CaCl2·2H2O, CaSO4·2H2O, SrCl2·6H2O, SrSO4, and ZnSO4·7H2O) as a function of pH, ionic strength, and surface area of the solid salt. The adsorption shows a pH dependence; this can be correlated with the charge on the nucleotide molecule which is determined by the state of protonation of the N-1 nitrogen of 5-AMP or N-3 nitrogen of 5-CMP and the phosphate oxygens. The adsorption which results from the binding between the nucleotide molecule and the salt surface is proposed as being due to electrostatic forces. It was concluded that the adsorption was reversible in nature. The adsorption shows a strong dependence upon ionic strength and decreases with increasing ionic strength. Surface area is shown to be an important factor in evaluating and comparing the magnitude of adsorption of nucleotides onto various mineral salts. The implications of the results of the study are discussed in terms of the importance of soluble mineral salts as adsorption sites in the characterization of the adsorption reactions of an adsorbed template in biogeochemical cycles. 相似文献
59.
A J Smith M Mondain-Monval P Simon K Andersen Berg O P Clausen P O Hofmo R Scholler 《Journal of reproduction and fertility》1987,81(2):517-524
Bromocriptine administration in the form of slow-release injections to male blue foxes during March-May abolished the normal spring rise in plasma prolactin concentrations seen in May and June. The spring moult was prevented and the treated animals retained a winter coat of varied quality and maturity until the end of the study in August. Plasma testosterone concentrations fell normally from March until August. Testicular regression was, however, delayed, although there were individual variations in response. Estimation by DNA flow cytometry in early July of the relative numbers of haploid, diploid and tetraploid cells in the testis showed that, in the treated animals, 74-80% of the cells were haploid (maturing germinal cells), 4-6% tetraploid (mainly primary spermatocytes) and the rest diploid cells (somatic cells and the remaining germinal cell types). In the control males, however, no haploid cells were detected and the majority of cells were diploid (93-99%). At castration in August, histological examination revealed various stages of testicular regression in the treated and control animals. 相似文献
60.
Covalent labeling of opioid receptors with 3H-D-Ala2-Leu5-enkephalin chloromethyl ketone. I. Binding characteristics in rat brain membranes 总被引:1,自引:0,他引:1
M Szücs M Belcheva J Simon S Benyhe G Tóth J Hepp M Wollemann K Medzihradszky 《Life sciences》1987,41(2):177-184
The chloromethyl ketone derivative of D-Ala2-Leu5-enkephalin was synthesized in a radioactive form, and the resulting compound (3H-DALECK) was used to label opioid receptors. 3H-DALECK binds with high affinity, specificity and saturability to rat brain membranes. The number of sites labeled is 130 fmoles/mg protein. Unlabeled opioids inhibited the binding of 3H-DALECK; etorphine and DAGO being most potent. A 10-fold preference for mu sites over delta was seen in site-specific competition experiments; while DALECK displayed low affinity for kappa sites of rat brain. DALECK irreversibly blocked a certain population of sites. Approximately 40% of 3H-DALECK binding at 15 min, and 60% at 60 min association time did not dissociate in the presence of a large excess of unlabeled DALECK and was resistant to washing. Autoradiography performed after SDS-PAGE revealed specific alkylation of proteins with molecular weight of 74, 65, 56, 43 and 34 kD. These results demonstrate the applicability of using 3H-DALECK to covalently label opioid receptors. 相似文献