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31.
Judith K. Brown Perla Subbaiah Therese Sarah 《Journal of cross-cultural gerontology》1994,9(2):231-254
Our cross-cultural study of the relationship between older women and their younger female kin examines women's hierarchies based on age and focuses on the exercise of authority by women, when such authority is traditional and accepted. Data were collected for two world-wide samples each consisting of 30 societies, varying in complexity, subsistence base, geographic location, and in customs related to women's lives. Three hypotheses were tested. The findings, which are statistically significant, suggest that the relationships between older women and their younger female kin are patterned and predictable, determined by the role of women in subsistence activities, by rules for post-marital residence, and by descent.When domination can only be exercised... directly, between one person and another, it can not take place overtly and must be disguised under the veil of enchanted relationships, the official model of which is presented by the relations between kinsmen.The gentle, invisible form of violence, which is never recognized as such... can not fail to be seen as the most economical mode of domination...The system is such that the dominant agents have a vested interest in virtue. (Bourdieu 1991191, 192, 194) 相似文献
32.
Summary The Save Our Sisters Project builds on the roles of 95 natural helpers to increase mammography screening among older African American women in a NC county. Natural helpers are lay people to whom others naturally turn for advice, emotional support, and tangible aid. Findings from 14 focus group interviews showed that older women seek out these individuals when they have a female-specific concern, rather than or before seeking help from professionals. The characteristics of natural helpers, revealed in the findings, were used to identify and recruit them to become trained lay health advisors in breast cancer education. Through the SOS Project, natural helpers provide a community-based system of care and social support that complements the more specialized role of health professionals; linking them to women through places and ways that no health professional could begin to acquire. The three roles of lay health advisors are: (1) to assist individuals in their social networks with needs that are difficult for professionals to address; (2) to negotiate with professionals for support from the health system; and (3) to mobilize the resources of associations in their community to sustain support from the health system. 相似文献
33.
Venoarterial extracorporeal membrane oxygenation (ECMO) was performed in five dogs without systemic heparinization to assess the feasibility of heparin-free ECMO. The surfaces of the inverted hollow-fiber-type oxygenator and circuit of the ECMO system were coated with heparin by the endpoint-attached (covalent-bonded) technique. No heparin was administered to the animal except for a small dose to maintain patency of the arterial line (1 IU/h). ECMO was run for 24 h at a pump flow of 50 ml/kg · min and was successful throughout the experiment in four of the five dogs. Scanning electron microscopy did not detect any blood clots in the oxygenator or circuit except for inside and outside the cannulas that were not coated with heparin in the carotid artery and jugular vein. Activated clotting time (ACT), fibrinogen, and anti-thrombin III (AT-III) activity remained within the normal physiological range. Serum heparin concentrations were low throughout the experiment, indicating minimal heparin release. Platelet levels decreased and fibrinopeptide B 15–42 (FPB 15–42) increased significantly after 6 h ECMO. D-dimer levels did not change throughout the experiment. ECMO was discontinued in one case after successful a 23-h run because of macroscopic clot formation at the oxygenator blood inlet. ACT had suddenly increased to 160 s approximately 1 h prior to this clot formation. These results suggest that the amount of systemic heparinization required can be substantially reduced by a heparin-coated ECMO system. Total abolishment of heparin administration in pediatric venoarterial ECMO may be possible by refinement of this technique. Monitoring of AT-III and FPB 15–42 in addition to ACT may be useful for early diagnosis of latent but ongoing coagulopathies during ECMO. 相似文献
34.
35.
In 13 healthy women and 6 virgins the cellular sensitization against sperm and seminal plasma antigens was demonstrated by an indirect lymphokin assay, the leucocyte migration inhibition test (LMI-test) using the following preparations: "washed" spermatozoa, seminal plasma and spermatozoa of the supernatant prepared with the "swim-up" technique. In both groups of women a cellular sensitization against sperm and seminal plasma antigens could be observed. Further, a dose dependent correlation was found in that way, that increasing concentrations of spermatozoa lead to an increased inhibition of macrophage migration. In virgins cellular sensitization against seminal plasma proteins did not differ from non-virgins, only the percentage of significant reactions in the LMI-Test was reduced. As low sperm concentrations (1 million ml-1), which represent best the physiological situation in the uterus, induced an enhanced migrations of macrophages the enhancement of macrophage migration is considered as physiological cellular sensitization of females against sperm-associated antigens. 相似文献
36.
37.
Eliahu Kalmanzon Yocheved Rahamim Yechezkel Barenholz Shmuel Carmeli Eliahu Zlotkin 《Toxicon》2003,42(1):63-71
Pahutoxin (PHN, choline chloride ester of 3-acetoxypalmitic acid) is a natural fish-killing (ichthyotoxic) agent derived from the defensive secretions of trunkfish. In spite of its obvious structural resemblance to synthetic cationic long-chain quaternary ammonium detergents, we show that PHN's action does not rely on its surfactant properties and is in fact, receptor-mediated. The above conclusion is supported by the following data: 1. Ichthyotoxicity is not related to its detergency or surfactivity, as indicated by the fact that the lethal concentration is about 1.5 orders of magnitude below its critical micelle concentration value (69 microM) and its liposomal/seawater partition coefficient is low (62-85); 2. The trunkfish is tolerant to its own pahutoxin; 3. Ichthyotoxicity occurs only upon application to the surrounding water, suggesting the existence of externally located receptors; 4. The receptor hypothesis was supported by the aid of equilibrium saturation binding assays revealing the presence of specific binding sites to PHN on the fish gill membranes; 5. The PHN tolerant trunkfish was shown to be devoid of PHN-binding sites. Some chemo-ecological, and environmental implications are discussed. 相似文献
38.
In congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, affected girls are born with ambiguous genitalia due to increased secretion of androgens in utero by the defective adrenal gland. Even though it is generally accepted that there are differences between male and female brain development, determining factors have been difficult to identify. Girls with CAH have frequently been studied to evaluate the impact of prenatal androgen exposure on psychological, psychosocial, and psychosexual development, and impairments in various areas have been identified. However, there is no comprehensive study available regarding the outcome of this chronic disorder in adult life. We studied the quality of life in women with CAH, with particular emphasis on how they cope with genital malformations, genital operations, and chronic disease as well as lifelong medication. The patients filled out questionnaires covering their physical state, psychological well-being, social relationships, and functional capacity, as well as questionnaires on psychosexual identification and psychosocial integration. The results were evaluated using a computerized statistical program for social studies. Out of a total of 94 patients above 18 years of age, 45 agreed to participate and were compared to 46 healthy, age-matched controls. Age at diagnosis was 2.31 ± 1.55 years and 38% suffered from the simple-virilizing, 45% from the salt-wasting, and 17.0% from the late-onset form of CAH. About one-third of patients had Prader stage 3 or 4 genital virilization. While the overall quality of life did not differ significantly, CAH patients were more often single (47.8% vs. 66.7%) and fewer of them had children (22.2% vs. 38.6%) compared to controls. Significant impairments were found in regard to body image and attitudes toward sexuality, but there was no increased homosexual preference. The women were successful in adjusting to illness and receiving social support. It is speculated that improved psychosocial adaptation is part of a coping mechanism that helps to maintain a high level of well-being despite impairment. Coping mechanisms should be identified and strengthened in order to help patients cope with their chronic illness. 相似文献
39.
E. C. Lazcano-Ponce P. Najera-Aguilar E. Buiatti P. Alonso-de-Ruiz P. Kuri L. Cantoral M. Hernandez-Avila 《Cancer causes & control : CCC》1997,8(5):698-704
A cross-sectional study was carried out in two geographic regions of Mexico - Oaxaca (rural area) and Mexico City (urban area) - to determine the main factors for predicting participation in Cervical Cytology Screening Programs (CCSP), in populations with high mortality due to cervical cancer. We included 4,208 women aged between 15 and 49 years, randomly selected through a national household-sample frame. Knowledge of what the Pap test is used for strongly predisposes use of CCSP in Mexico City (odds ratio [OR] = 46.1, 95 percent confidence interval [CI] = 33.1-64.1) and Oaxaca state (OR = 61.5, CI = 42.0-89.9), as well as high socioeconomic level (Mexico: OR = 2.0, CI = 1.1-7.6; Oaxaca: OR = 4.1, CI = 3.1-5.3), high education level (Mexico: OR = 3.6, CI = 1.5-8.8; Oaxaca: OR = 5.3, CI = 2.8-10.0), and access to social security (Mexico: OR = 1.7, CI = 1.4-2.2; Oaxaca: OR = 2.2, CI = 1.8-2.7). Low coverage of the CCSP is confirmed as an important problem in Mexico. 相似文献
40.
Postnatal development of NR1, NR2A and NR2B immunoreactivity in the visual cortex of the rat 总被引:4,自引:0,他引:4
N-Methyl-D-aspartate receptors (NMDARs) are critically involved in some types of synaptic plasticity. The NMDAR subunits NR1, NR2A and NR2B are developmentally regulated, and it has been proposed that developmental changes in their expression may underlie developmental changes in cortical plasticity. Age-dependent change in cortical plasticity is most commonly measured by the monocular deprivation effect, which occurs during a critical period between P22 and P50 in the rat. Although the development of NMDAR subunits has been studied from birth through the fourth postnatal week, there is only meager information from older ages when visual plasticity ends. We hypothesized that there will be significant age-dependent change in expression of NR1, NR2A or NR2B between P22, when the cortex is plastic, and P90, when it is not. We applied specific antibodies recognizing NR1, NR2A and NR2B to the primary visual cortex at P14, P22, P30, P45 and P90. We found age-dependent changes in NR1-IR that were negatively correlated with changes in NR2A-IR; these subunits are not regulated in unison. In contrast, NR2A-IR and NR2B-IR were positively correlated. NR2A-IR and NR2B-IR both passed through a developmental minimum around P45, then recovered to approximately their P22 level. NR1-IR passed through a maximum at P45. There were no significant differences between P22 and P90. These results do not support the simple hypothesis that the loss of plasticity corresponds to a simple transition from juvenile levels of NMDAR subunit proteins to new adult levels. On the other hand, the results do confirm the hypothesis that there are significant changes in processing of NMDAR proteins during the time that plasticity is lost. How these changes of IR relate to synaptic transmission and plasticity needs to be clarified. 相似文献