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991.
Thirteen male and twenty female rhesus monkeys (Macaca mulatta), aged 9-12 months, living as members of long term captive social groups, were observed in order to quantify sex differences in a variety of behaviour patterns. Six males had been treated with a GnRH agonist (Meterelin: M) during their first six postnatal months, in order to block the surge of testosterone which occurs at this time. Ten females had been treated with testosterone (T) during their first six months, in order to mimic the postnatal T surge seen in males. The remaining 7 males and 10 females acted as control subjects. Marked sex differences were measured in frequencies of play and socio-sexual behaviour in these juvenile monkeys. However, neither M nor T treatments produced any significant changes in frequencies of these behaviour patterns. Although M-treated males showed a tendency (p < 0.1) to groom others for longer periods than control males, and control females tended to spend more time alone than T-treated females, we were unable to measure any significant (p < 0.05) effects of either M- or T-treatment upon affiliative behaviour in juvenile rhesus monkeys. We conclude, therefore, that the postnatal T surge in male rhesus monkeys does not affect development of sexually dimorphic and associated patterns of behaviour. Presumably, organisational effects of T upon these behaviour patterns must be completed before birth in this species. 相似文献
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ML Standaert L Galloway P Karnam G Bandyopadhyay J Moscat RV Farese 《Canadian Metallurgical Quarterly》1997,272(48):30075-30082
Insulin provoked rapid increases in enzyme activity of immunoprecipitable protein kinase C-zeta (PKC-zeta) in rat adipocytes. Concomitantly, insulin provoked increases in 32P labeling of PKC-zeta both in intact adipocytes and during in vitro assay of immunoprecipitated PKC-zeta; the latter probably reflected autophosphorylation, as it was inhibited by the PKC-zeta pseudosubstrate. Insulin-induced activation of immunoprecipitable PKC-zeta was inhibited by LY294002 and wortmannin; this suggested dependence upon phosphatidylinositol (PI) 3-kinase. Accordingly, activation of PI 3-kinase by a pYXXM-containing peptide in vitro resulted in a wortmannin-inhibitable increase in immunoprecipitable PKC-zeta enzyme activity. Also, PI-3,4-(PO4)2, PI-3,4,5-(PO4)3, and PI-4,5-(PO4)2 directly stimulated enzyme activity and autophosphoralytion in control PKC-zeta immunoprecipitates to levels observed in insulin-treated PKC-zeta immunoprecipitates. In studies of glucose transport, inhibition of immunoprecipitated PKC-zeta enzyme activity in vitro by both the PKC-zeta pseudosubstrate and RO 31-8220 correlated well with inhibition of insulin-stimulated glucose transport in intact adipocytes. Also, in adipocytes transiently expressing hemagglutinin antigen-tagged GLUT4, co-transfection of wild-type or constitutive PKC-zeta stimulated hemagglutinin antigen-GLUT4 translocation, whereas dominant-negative PKC-zeta partially inhibited it. Our findings suggest that insulin activates PKC-zeta through PI 3-kinase, and PKC-zeta may act as a downstream effector of PI 3-kinase and contribute to the activation of GLUT4 translocation. 相似文献
996.
S Mazzoli D Trabattoni S Lo Caputo S Piconi C Blé F Meacci S Ruzzante A Salvi F Semplici R Longhi ML Fusi N Tofani M Biasin ML Villa F Mazzotta M Clerici 《Canadian Metallurgical Quarterly》1997,3(11):1250-1257
HIV-specific mucosal and cellular immunity was analyzed in heterosexual couples discordant for HIV status in serum and in HIV-unexposed controls. HIV-specific IgA but not IgG was present in urine and vaginal wash samples from HIV-exposed seronegative individuals (ESN), whereas both IgA and IgG were observed in their HIV-seropositive partners; antibodies were not detected in low-risk controls. Envelope protein (Env) peptide-stimulated interleukin-2 (IL-2) production by peripheral blood mononuclear cells (PBMCs) was detected in 9 out of 16 ESNs, 5 out of 16 HIV-infected patients and 1 out of 50 controls. Env peptide-stimulated PBMCs of ESNs produced more IL-2 and less IL-10 compared with those of HIV-infected individuals; no differences were observed in chemokine production or in CCR5 expression. These data demonstrate that a compartmentalized immune response to pathogens is possible in humans and raise the possibility of protective roles for cell-mediated immunity and mucosal IgA in HIV-seronegative individuals exposed to HIV. 相似文献
997.
The possibility of detecting the passage of emboli through the carotid artery via skin electrodes is investigated. Impedance changes calculated using both finite-element and theoretical methods indicate that detection of emboli in vivo should be possible. 相似文献
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Davis Brown 《Journal of the American Ceramic Society》1928,11(8):228-234
Illustrating and describing the application of various power transmitting and speed reducing devices with suggestions for further simplifying the methods of applying motors to machines to be driven. 相似文献