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991.
Macrophages and neutrophils from human milk phagocytose and kill Staphylococcus aureus and Escherichia coli in vitro after opsonisation by the aqueous phase of milk as effectively as blood leucocytes in serum. They also phagocytose Candida albicans. The overgrowth of E coli resulting from the addition of iron to cultures of the organism in the aqueous phase of milk is not influenced by the presence of cells. We conclude that the phagocytosis and killing of bacteria by milk cells may contribute to the lower incidence of infection among breast-fed than artificially fed babies. 相似文献
992.
Gary M. Williams Edilberto Bermudez Richard H. C. San Peter J. Goldblatt Michael F. Laspia 《In vitro cellular & developmental biology. Plant》1978,14(10):824-837
Summary Primary cultures of rat hepatocytes survived well for up to 4 days in defined medium in the presence of dexamethasone but
not in its absence. The loss of viability was accompanied by a loss of ultrastructural features characteristic of hepatocytes.
The cultures began producing plasminogen activator and a neutral protease after 24 hr in culture. Dexamethasone inhibited
the production of both of these substances. The deterioration of the cultures appeared not to be related to plasminogen activator,
but prolongation of survival by a variety of protease inhibitors suggested that the neutral protease might contribute to deterioration.
Dr. Goldblatt was supported by Grant No. SG-87 from the American Cancer Society as an American Cancer Society Scholar while
on sabbatical leave from the Department of Pathology, University of Connecticut Health Center, Farmington, Connecticut.
This study was supported by Contracts NO1-CP-55705 from the National Cancer Institute and 68-02-2483 from the Environmental
Protection Agency. 相似文献
993.
The purpose of this study was to examine the relative effectiveness of electromyographic biofeedback training(EMG BFT), remeditation, and progressive muscle relaxation(PMR) in eliciting a relaxation or trophotropic response as measured by frontalis muscle tension, heart rate, electrodermal response, respiration rate, and skin temperature. Fifty-four college students were randomly assigned to one of five groups:(1) control,(2) placebo control,(3) EMG BFT,(4) meditation,(5) PMR. After baseline measures were obtained subjects were trained in 10 30-minute training sessions and posttested. Comparisons by ANOVAs indicated there was a significant decrease in muscle tension in the EMG BFT and meditation groups and significant decreases in respiration rate in the meditation and PMR groups. No other changes were attributed to treatment. 相似文献
994.
The synthesis of ((±)-16-thioketal and 16-keto PGE2 methyl ester (
and
) is herein described. 相似文献
995.
996.
997.
Progesterone is rapidly metabolized by neural cells in the rat. Progesterone could, therefore, act as a “prohormone,” stimulating lordosis behavior in estrogen-primed rats only after metabolic conversion. Were such the case, one might expect one or more of the naturally occurring metabolites of progesterone to be more potent than the parent compound. Estradiol benzoate-primed rats were therefore administered intravenously 200 μg of progesterone or one of five immediate metabolites of progesterone. The steroid 20α-dihydroprogesterone was found to be more potent than progesterone. Both 20α-hydroxy-5α-pregnan-3-one and 3α-hydroxy-5α-pregnan-20-one were less potent than progesterone, but more potent than the vehicle propylene glycol. Neither 5α-pregnane-3α, 20α-diol nor 5α-pregnane-3,20-dione (dihydroprogesterone, DHP) differed from the vehicle in potency. The data suggest that 20α-dihydroprogesterone, which is secreted at high levels during the estrous cycle, could play a role in the regulation of sexual receptivity. The data also suggest that 5α-reduction is probably not crucial for progesterone's action. 相似文献
998.
Babetta L. Marrone Jorge F. Rodriguez-Sierra Harvey H. Feder 《Hormones and behavior》1977,8(3):391-402
Progesterone has two types of inhibitory effects on female sexual behavior that have been well-documented in the guinea pig. The first occurs when high levels of progesterone are present around the start of the estrogen-priming process (“concurrent inhibition”). The second occurs immediately after the display of an estrogen-progesterone-induced period of estrous behavior (“sequential inhibition”). In the present set of experiments, we show that the rat, like the guinea pig, is capable of exhibiting both of these inhibitory effects of progesterone. However, rats require higher doses of progesterone than guinea pigs, at least for concurrent inhibition to be evident. In addition, we show that the dose of progesterone required in a single injection to produce concurrent inhibition is higher than the dose required to produce sequential inhibition in rats. A theory of how progesterone may be accomplishing its inhibitory effects on female sexual behavior in rodents is presented. 相似文献
999.
1000.
Richard L. Jantz 《American journal of physical anthropology》1977,46(1):171-176
Correlations between ridge-counts on the ten fingers were compared by race and sex in 11 samples representing Negroes and Caucasians: five from subsaharan Africa, one American Black, three European, one American White and one from India. The samples of European ancestry showed no consistent sex difference in mean correlation, although female American Whites significantly exceeded males. In three of the six Negro samples and in the Parsis of India males showed significantly higher average correlations than females. The pattern of sex and race differences suggests that the sex chromosomes, particularly the Y chromosome, play a role in dermal ridge development. 相似文献