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1.
Representative energy data for a human population can be produced by combining randomly sampled time allocation observations with activity-specific energy expenditure measurements. Research to produce representative energy data for adults of a population of Machiguenga Indians has recently been conducted in lowland, southeastern Peru. Marked contrast was found between the sexes for average married adults in energy expended on an average day. Men spent about 3,200 kcals and women, about 1,925; ratio: 1.66 to 1. In general, men tended to work at somewhat more energetic activities and for longer periods than did women. In addition to sex-role-related task differences were contrasts in uses of technological items and in respective work settings. These representative behavior data permit direct estimates of population-level energy requirements for average days, seasons, or for 1 year.  相似文献   
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In an initial trial of glibenclamide in the treatment of maturity onset diabetes mellitus 28 patients were treated for up to one year and no toxic effects or side-effects were encountered. The hypoglycaemic potency of this drug is such that 5 mg. of glibenclamide corresponds to about 1,500 mg. of tolbutamide and 375 mg. of chlorpropamide.  相似文献   
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Dihydrotestosterone glucuronide (DHTG), a series of 5 alpha-bile acids, or allo-bile acids (3 alpha-hydroxy-5 alpha-cholanic acid, 3-keto-5 alpha-cholanic acid and 3 beta-hydroxy-5 alpha-cholanic acid) and their normal bile acid analogues (3 alpha-hydroxy-5 beta-cholanic acid or lithocholate, 3-keto-5 beta-cholanic acid and 3 beta-hydroxy-5 beta-cholanic acid) were administered intravenously to female rats in order to determine their effects on bile flow. All agents caused a rapid and profound inhibition of bile flow which was dose-dependent. The logarithm of the dose vs the cholestatic response curve for DHTG, the allo-bile acids and lithocholate were all parallel. DHTG was the most potent congener and was two times more potent than 3-keto-5 alpha-cholanic acid and 5 times more potent than lithocholate. These data indicate that the glucuronic acid moiety and the trans configuration of the A and B rings of the steroid nucleus confer the greatest cholestatic potency.  相似文献   
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Thirty-four independent nonviable c-locus mutations (types cal, albino lethal and cas, albino subvital), derived from radiation experiments, were tested for involvement of nearby markers tp, Mod-2, sh-1, and Hbb: 10, 22, and 2 involved, respectively, none of these markers, Mod-2 alone, and Mod-2 plus sh-1. When classified on this basis, as well as according to developmental stage at which homozygotes die, and by limited complementation results, the 34 independent mutations fell into 12 groups. From results of a full-scale complementation grid of all 435 possible crosses among 30 of the mutations, we were able to postulate an alignment of eight functional units by which the 12 groups fit a linear pattern. Abnormal phenotypes utilized in the complementation study were deaths at various stages of prenatal or postnatal development, body weight, and reduction or absence of various enzymes. Some of these phenotypes can be separated by complementation (e.g., there is no evidence that mitochondrial malic enzyme influences survival at any age); others cannot thus be separated (e.g., glucose-6-phosphatase deficiency and neonatal death).—We conclude that all of the nonviable albino mutations are deficiencies overlapping at c, and ranging in size from <2cM to 6-11 cM. The characterization of this array of deficiencies should provide useful tools for gene-dosage studies, recombinant-DNA fine-structure analyses, etc. Since many of the combinations of lethals produce viable albino animals that resemble the standard c/c type, we conclude (a) that the c locus contains no sites essential for survival, and (b) that viable nonalbino c-locus mutations (cxv) are the result of mutations within the c cistron. Viable albinos (cav, the majority of radiation-induced c-locus mutations) may be intracistronic mutations or very small deficiencies.  相似文献   
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A series of three experiments was performed to determine the effects of 30-day exposures to uniform 60-Hz electric fields (100 kV/m) on reproduction and on growth and development in the fetuses and offspring of rats. In the first experiment, exposure of females for 6 days prior to and during the mating period did not affect their reproductive performance, and continued exposure through 20 days of gestation (dg) did not affect the viability, size, or morphology of their fetuses. In the second experiment, exposure of the pregnant rat was begun on 0 dg and continued until the resulting offspring reached 8 days of age. In the third experiment, exposure began at 17 dg and continued through 25 days of postnatal life. In the second and third experiments, no statistically significant differences suggesting impairment of the growth or survival of exposed offspring were detected. In the second experiment, a significantly greater percentage of the exposed offspring showed movement, standing, and grooming at 14 days of age than among-sham-exposed offspring. There was a significant decrease at 14 days in the percentage of exposed offspring displaying the righting reflex in the second experiment and negative geotropism in the third experiment. These differences were all transient and were not found when the animals were tested again at 21 days of age. Evaluation of the reproductive integrity of the offspring of the second experiment did not disclose any deficits.  相似文献   
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ABSTRACT Telemetry data have been widely used to quantify wildlife habitat relationships despite the fact that these data are inherently imprecise. All telemetry data have positional error, and failure to account for that error can lead to incorrect predictions of wildlife resource use. Several techniques have been used to account for positional error in wildlife studies. These techniques have been described in the literature, but their ability to accurately characterize wildlife resource use has never been tested. We evaluated the performance of techniques commonly used for incorporating telemetry error into studies of wildlife resource use. Our evaluation was based on imprecise telemetry data (mean telemetry error = 174 m, SD = 130 m) typical of field-based studies. We tested 5 techniques in 10 virtual environments and in one real-world environment for categorical (i.e., habitat types) and continuous (i.e., distances or elevations) rasters. Technique accuracy varied by patch size for the categorical rasters, with higher accuracy as patch size increased. At the smallest patch size (1 ha), the technique that ignores error performed best on categorical data (0.31 and 0.30 accuracy for virtual and real data, respectively); however, as patch size increased the bivariate-weighted technique performed better (0.56 accuracy at patch sizes >31 ha) and achieved complete accuracy (i.e., 1.00 accuracy) at smaller patch sizes (472 ha and 1,522 ha for virtual and real data, respectively) than any other technique. We quantified the accuracy of the continuous covariates using the mean absolute difference (MAD) in covariate value between true and estimated locations. We found that average MAD varied between 104 m (ignore telemetry error) and 140 m (rescale the covariate data) for our continuous covariate surfaces across virtual and real data sets. Techniques that rescale continuous covariate data or use a zonal mean on values within a telemetry error polygon were significantly less accurate than other techniques. Although the technique that ignored telemetry error performed best on categorical rasters with smaller average patch sizes (i.e., ≤31 ha) and on continuous rasters in our study, accuracy was so low that the utility of using point-based approaches for quantifying resource use is questionable when telemetry data are imprecise, particularly for small-patch habitat relationships.  相似文献   
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A hunter-killed wild turkey (Meleagris gallopavo silvestris) was submitted for examination because of numerous 2 to 30 mm diameter, yellowish, hard nodules in the skin. The nodules were confined to the skin and did not involve subcutaneous tissues. Nodules consisted of dilated feather follicles packed with a caseous tan to pale yellow material. Histologically, affected feather follicles were markedly dilated and filled with laminated keratin debris. The lesions were determined to be multiple feather follicle cysts of unknown etiology.  相似文献   
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