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81.
Hyperglycosylated chorionic gonadotropin (CG-H) signals placental cytotrophoblast cell growth and invasion, and chorionic gonadotropin (CG) promotes uterine vascularization. A hypothesis is presented relating the evolution of these molecules to the evolution of human hemochorial implantation and that of the human brain. Deep placental invasion, vascularization and hemochorial placentation, under the influence of CG and CG-H, are a critical part of the nutrition and energy-generating mechanisms needed for human brain development and thus for the evolution of humans. Insufficient CG-H production and the resulting inappropriate implantation is associated with an unduly high incidence of pregnancy failures in humans. Low levels of CG-H and inappropriate hemochorial placentation also appear to be associated with subsequent preeclampsia. It is also of note that human CG-H drives invasion by gestational trophoblastic neoplasms that have been described only in humans.  相似文献   
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PURPOSE: Many recent attempts have been made to eliminate health services minors can receive without parental consent or notification. One argument is that these "confidential" services undermine the parent-teen relationship. The objective of this study was to evaluate whether confidential services impact adolescent's communication with parents about their health. METHODS: This cross-sectional study included 59 adolescents (ages 12-21) seeking health services at an urban teen clinic in Minneapolis, MN. Participants were divided based on reasons for presenting at the clinic; confidential or non-confidential services. The main outcome variables were the following: discussion of clinic visit with parent, discussion of reason for clinic visit with parent, and communication with parent if diagnosed with a potentially serious health condition. RESULTS: The two groups were equally divided; 42.4% came for non-confidential services and 57.6% came for confidential services. Of the 59 participants, 69.5% told their parents they were coming to clinic. However, only 43.1% reported they would not tell their parent if they had a serious health problem; there was an equal split between the confidential services and non-confidential services groups. A statistical difference was not found between the confidential services and non-confidential services groups for any of the outcome variables. CONCLUSIONS: Obtaining confidential services was not a barrier to discussion with parents about clinic visit, reasons for coming to clinic, or telling their parent if they had a serious health care problem. Clinicians should continue to advocate for confidential services while encouraging open communication between adolescents and their parents.  相似文献   
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To better understand barriers service providers may face when advocating for survivors, a study using grounded theory and qualitative, semistructured interviews was conducted of rape victim advocates (N= 25) working in rape crisis centers in a large metropolitan area. Broader societal attitudes framed and were reflected in institutional responses to victims and in barriers faced by advocates working with survivors. Organizational barriers noted by advocates related to resources, environmental factors, professionalization, and racism. Staff burnout was a major barrier affecting advocates' ability to help survivors. Finally, the most salient direct service barrier was secondary victimization by criminal justice and medical or mental health systems.  相似文献   
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