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571.
We used a monoclonal antibody (PS1) to a carbohydrate antigen to study the development of the oocyte and follicle during early stages of differentiation in several mammalian species. This antigen has been shown to localize within the cytoplasm of oocytes in primordial follicles as well as in growing oocytes. It is also localized within distinct layers of the zona pellucida (ZP) of developing follicles. Although this antibody was made against a specific ZP glycoprotein, the antigen also appears to be abundant in cells of the ovarian surface epithelium (OSE). The localization of this carbohydrate moiety has been observed in ovaries of rabbits of different ages as well as in the ovarian surface epithelium of other mammalian species including cat, cynomolgus monkey, baboon, and human. These studies demonstrate that there is an abundant carbohydrate antigenic determinant which is associated with both the mammalian oocyte and the ovarian surface epithelium but which is not apparent in other ovarian cell types or in non-ovarian secretory epithelium. This antibody probe should provide a valuable tool for studying the development and differentiation of the ovary, since this antigen is associated with two highly differentiated but distinct cell types.  相似文献   
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Hormones and growth factors are generally released from larger precursors by limited proteolysis. The causative agents remain poorly defined with respect to location and properties. One subset of proteases, the glandular kallikreins, have been implicated in a few cases, in part because of their specific association with mature forms of some hormones. However, limited distribution and low copy number in some species cast doubt on this hypothesis, and they may well play other physiological functions that remain to be elucidated.  相似文献   
575.
A unique ovarian follicle cell culture system has been established to analyze the effects of extracellular matrix (ECM) on early granulosa cell differentiation. Primary and early secondary follicles isolated from ovaries of sexually immature rabbits were grown on poly-D-lysine or Englebreth-Holm-Swarm basement membrane biomatrix substrata (EHS) in serum-free, hormonally defined medium. Granulosa cells from these follicles were examined for growth pattern characteristics and for secretory protein synthesis by two-dimensional (2D) PAGE. Whereas some proteins were synthesized by cells on either matrix, the expression of other secreted proteins was markedly affected by the ECM used. Secretion of zona pellucida (ZP) proteins was demonstrated by ELISA assays and immunoblots of one-dimensional (1D) and 2D-PAGE separations of secreted proteins probed with monoclonal and epitope-selected antibodies. Expression of two ZP proteins was altered by ECM: 55-kDa endo-beta-galactosidase (EBGD)-treated ZP glycoprotein (55-kDaEBGD) was secreted by cells grown on either ECM, but a greater amount of 75-kDaEBGD was secreted by cells grown on poly-D-lysine. These studies are the first to show that granulosa cells from early-stage follicles express ZP proteins in vitro in the absence of oocytes, although proper post-translational modification may not occur. They also demonstrate the dramatic effect of ECM on the expression of these and other secretory proteins.  相似文献   
576.
This study examines the behavioural consequences of the silent bared teeth display (SBT) and the relaxed open mouth display (ROM) in the chimpanzee, and discusses functional similarities with smiling and laughing (respectively) in humans. Rates of affinitive behaviour increase (in relation to baseline levels) following SBT, suggesting that SBT is a signal of affinity. ROM is observed primarily during play, and dyadic play bouts are significantly longer when ROM is bidirectional, indicating that it may be a signal of play. Rates of affinitive behaviour also increased after ROM, suggesting that both displays may have a similar ultimate (evolutionary) function – social bonding; this could explain convergence of the two displays in humans.  相似文献   
577.
We investigated locomotor and postural behavior during terminal branch feeding in order to gain a better understanding of the motor capabilities of primates. We videotaped wild, juvenile bonnet macaques (Macaca radiata) in India as they fed on flower nectar in a simal tree (Bombax malabaricum). Kinematic analysis revealed that they select specific support surfaces and movements that, for their body design and postures, maximize lateral stability and minimize the chances of falling. These choices are made even though the distance and duration of travel to a selected target are frequently increased. Our discussion focuses on particular concepts of how primates contend with balance problems arboreally, potential reasons for changes in footfall patterns, and how the tail contributes to arboreal locomotion and posture. We concluded that balance problems due to the ratio of body size to branch size are usually avoided, at least among juvenile bonnet macaques, by placing the hands and feet on branches extending laterally from the central support branch and not on the central branch itself. The lateral branches permit a wide base of support, which increases lateral stability. Second, juvenile bonnet macaques have a striking ability to rapidly and repeatedly adapt their gait patterns to changing substrate design with minimal interruption to overall progression. Third, primate tails that are not morphologically specialized for prehension nevertheless have important prehensile and sensory functions in arboreal locomotion and posture.  相似文献   
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This study examines the socioeconomic and familial background of Irish Catholic priests born between 1867 and 1911. Previous research has hypothesized that lack of marriage opportunities may influence adoption of celibacy as part of a religious institution. The present study traced data from Irish seminary registries for 46 Catholic priests born in County Limerick, Ireland, using 1901 Irish Census returns and Land Valuation records. Priests were more likely to originate from landholding backgrounds, and with landholdings greater in size and wealth than the local average. Priests were found to originate from families with more sons than the national average, but with similar numbers of daughters. These findings are discussed in relation to competition for resources and lineage survival strategies.  相似文献   
580.
Arbovirus infection in Aedes aegypti has historically been quantified from a sample of the adult population by pooling collected mosquitoes to increase detectability. However, there is a significant knowledge gap about the magnitude of natural arbovirus infection within areas of active transmission, as well as the sensitivity of detection of such an approach. We used indoor Ae. aegypti sequential sampling with Prokopack aspirators to collect all mosquitoes inside 200 houses with suspected active ABV transmission from the city of Mérida, Mexico, and tested all collected specimens by RT-PCR to quantify: a) the absolute arbovirus infection rate in individually tested Ae. aegypti females; b) the sensitivity of using Prokopack aspirators in detecting ABV-infected mosquitoes; and c) the sensitivity of entomological inoculation rate (EIR) and vectorial capacity (VC), two measures ABV transmission potential, to different estimates of indoor Ae. aegypti abundance. The total number of Ae. aegypti (total catch, the sum of all Ae. aegypti across all collection intervals) as well as the number on the first 10-min of collection (sample, equivalent to a routine adult aspiration session) were calculated. We individually tested by RT-PCR 2,161 Aedes aegypti females and found that 7.7% of them were positive to any ABV. Most infections were CHIKV (77.7%), followed by DENV (11.4%) and ZIKV (9.0%). The distribution of infected Aedes aegypti was overdispersed; 33% houses contributed 81% of the infected mosquitoes. A significant association between ABV infection and Ae. aegypti total catch indoors was found (binomial GLMM, Odds Ratio > 1). A 10-min indoor Prokopack collection led to a low sensitivity of detecting ABV infection (16.3% for detecting infected mosquitoes and 23.4% for detecting infected houses). When averaged across all infested houses, mean EIR ranged between 0.04 and 0.06 infective bites per person per day, and mean VC was 0.6 infectious vectors generated from a population feeding on a single infected host per house/day. Both measures were significantly and positively associated with Ae. aegypti total catch indoors. Our findings provide evidence that the accurate estimation and quantification of arbovirus infection rate and transmission risk is a function of the sampling effort, the local abundance of Aedes aegypti and the intensity of arbovirus circulation.  相似文献   
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