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Using a highly sensitive allele-specific PCR amplification method, we have previously shown that maternal cells could be detected in all 10 cord bloods tested. This raised the question of whether maternal cells are released into cord blood during the process of delivery or whether they are already present during pregnancy. We have now used the same PCR method to detect the presence of maternal cells in nine fetal blood samples collected at different gestational ages. Maternal cells were detected in eight samples obtained between 24 and 35 weeks of gestation. They were estimated to amount between 10(-4) and 10(-5) of nucleated fetal blood cells. In two cases mononuclear and polymorphonuclear cell fractions were separated by Ficoll gradient centrifugation and maternal cells were detected as comparable levels in both fractions. Maternal cells could not be detected in the one fetal blood sample obtained at 20 weeks of gestation, suggesting that maternal cells could appear at detectable levels in fetal blood during the third trimester of pregnancy. These results are discussed in terms of materno-fetal immune tolerance and of transmission of viruses (and more specifically of the human immunodeficiency virus) from mother to child.  相似文献   
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OBJECTIVE: To assess Filipino, Turkish and Vietnamese women's views about their care during the postnatal hospital stay. DESIGN: Interviews were conducted with recent mothers in the language of the women's choice, 6-9 months after birth, by three bilingual interviewers. PARTICIPANTS: Three hundred and eighteen women born in the Philippines (107), Turkey (107) and Vietnam (104) who had migrated to Australia. SETTING: Women were recruited from the postnatal wards of three maternity teaching hospitals in Melbourne, Australia, and interviewed at home. FINDINGS: Overall satisfaction with care was low, and one in three women left hospital feeling that they required more support and assistance with both baby care and their own personal needs. The method of baby feeding varied between the groups, with women giving some insight into the reason for their choice. A significant minority wanted more help with feeding, irrespective of the method. The need for rest was a recurrent theme, with women stating that staff's attitudes to individual preferences, coupled with lack of assistance, made this difficult. The majority of comments women made regarding their postnatal stay focused on the attitude and behaviour of staff and about routine aspects of care. Issues related to culture and cultural practices were not of primary concern to women. CONCLUSION: Maternity services need to consider ways in which care can focus on the individual needs and preferences of women.  相似文献   
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OBJECTIVE: To examine the temporal integration of vascular endothelial growth factor (VEGF), which has been shown to be present in wound fluid, with the putatively related processes of wound fluid oxygen content, wound angiogenesis, and granulation tissue formation. SUMMARY BACKGROUND DATA: During cutaneous wound repair, new tissue formation starts with reepithelialization and is followed by granulation tissue formation, including neutrophil and macrophage accumulation, fibroblast ingrowth, matrix deposition, and angiogenesis. Because angiogenesis and increased vascular permeability are characteristic features of wound healing, VEGF may play an important role in tissue repair. METHODS: A ventral hernia, surgically created in the abdominal wall of female swine, was repaired using silicone sheeting and skin closure. Over time, a fluid-filled wound compartment formed, bounded by subcutaneous tissue and omentum. Ultrasonography was performed serially to examine the anatomy and dimensions of the subcutaneous tissue and wound compartment. Serial wound fluid samples, obtained by percutaneous aspiration, were analyzed for PO2, PCO2, pH, and growth factor concentrations. RESULTS: Three independent assays demonstrate that VEGF protein is present at substantially elevated levels in a wound fluid associated with the formation of abdominal granulation tissue. However, the wound fluid is not hypoxic at any time. Serial sampling reveals that transforming growth factor beta-1 protein appears in the wound fluid before VEGF. CONCLUSIONS: The results suggest that VEGF is a prominent regulator of wound angiogenesis and vessel permeability. A factor other than hypoxia, perhaps the earlier appearance of another growth factor, transforming growth factor beta-1, may positively regulate VEGF appearance in the wound fluid.  相似文献   
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