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101.
102.
The latest remarkable technological advances in assisted reproduction, which enable cryopreservation of spermatozoa, embryos and ovarian tissue, raise difficult and debatable legal, social, ethical and moral issues concerning the right to posthumous reproduction. Furthermore, reports on the attitudes of the general public and of centres licensed for infertility treatment in the United Kingdom found that the majority of women and centres support the idea of posthumous reproduction. In this paper we review the data published on this issue, and after considering the various aspects, we conclude that each case should be discussed and authorized by a multidisciplinary committee that includes physicians, clergy, psychiatrists, psychologists, sociologists and other appropriate parties. In our opinion, the main principles that should guide this committee would allow posthumous reproduction in the context of marriage when a prior consent exists. For unmarried persons, post-mortem donation of gametes should be done only anonymously, if they are in agreement with existing laws concerning infertility treatments in every country and after appropriate consent and proper counselling. Moreover, any case which involves consanguinity or a possibility of incest should be forbidden, both for ethical and genetic reasons. In a case of pre-existing siblings, they should be consulted and their informed consent should be granted in advance so as to avoid legal problems in the inheritance of property.   相似文献   
103.
Laser welding 0.016 x 0.022 in. beta-Ti, Ni-Ti, and Co-Cr-Ni orthodontic wires was investigated by measuring joint tensile strength, measuring laser penetration depth, determining metallurgical phases using micro X-ray diffraction (micro-XRD), and examining microstructures with an scanning electron microscope (SEM). Welding was performed from 150 to 230 V. Mean tensile strength for Ni-Ti groups was significantly lower (p < 0.05) than for most other groups of laser-welded specimens. Although mean tensile strength for beta-Ti and Co-Cr-Ni was significantly lower than for control specimens joined by silver soldering, it was sufficient for clinical use. The beta-Ti orthodontic wire showed deeper penetration depth from laser welding than the Ni-Ti and Co-Cr-Ni orthodontic wires. Micro-XRD patterns of laser-welded beta-Ti and Ni-Ti obtained 2 mm from the boundary were similar to as-received specimens, indicating that original microstructures were maintained. When output voltages of 190 V and higher were used, most peaks from joint areas disappeared or were much weaker, perhaps because of a directional solidification effect, evidenced by SEM observation of fine striations in welded beta-Ti. Laser welding beta-Ti and Co-Cr-Ni wires may be acceptable clinically, since joints had sufficient strength and metallurgical phases in the original wires were not greatly altered.  相似文献   
104.
Daniels  TM; Fass  DN; White  JG; Bowie  EJ 《Blood》1986,67(4):1043-1047
We report a new bleeding disease--storage pool deficiency (SPD) of platelets--in pigs from the Mayo swine colony of homozygous von Willebrand's disease (vWD) and of heterozygous carriers of vWD. Levels of factor VIII, von Willebrand factor antigen (vWF:Ag), and ristocetin cofactor (RCof) were similar in the vWD carriers and SPD pigs. The latter pigs, however, had bleeding times of 15 minutes or more and were severe bleeders, in contrast to clinically normal vWD carriers. Platelet aggregation in response to collagen was reduced in most SPD pigs. Total platelet content of ADP, ATP, and serotonin was less than that of normal pigs. While the initial uptake of 14C-labeled serotonin into platelets was similar in SPD and normal pigs, retention of serotonin was reduced in platelets of SPD pigs. Transmission electron microscopy showed a large decrease of dense bodies in the platelets of SPD pigs. These findings support a diagnosis of SPD. Genetic analyses suggest an autosomal recessive mode of inheritance. A breeding program is under way to produce pigs affected only at the SPD gene, thus allowing further characterization of SPD and SPD-carrier pigs.  相似文献   
105.
While the Weight Efficacy Lifestyle Questionnaire (WEL) shows promise as a measure of self-efficacy for eating control, there is a lack of research examining the psychometric properties of this measure with ethnic minorities. The current study examined the WEL with a sample of 144 overweight and obese African American females. Analyses indicated similar self-efficacy levels compared to predominantly Caucasian samples. Supporting the validity of the WEL, participants undergoing obesity treatment demonstrated modest improvement in WEL scores, while standard care participants showed no changes in self-efficacy over time. Factor analysis indicated a four-factor structure rather than the five factors previously found. The four-factor structure accounted for 61.85% of the variance. Results indicate the WEL may be a valid measure of self-efficacy for overweight and obese African American women, although researchers should be mindful of the variation in scale properties when using the WEL with this population.  相似文献   
106.
The alpha2 adrenergic receptor (α2-AR) antagonist yohimbine is a widely used tool for the study of anxiogenesis and stress-induced drug-seeking behavior. We previously demonstrated that yohimbine paradoxically depresses excitatory transmission in the bed nucleus of the stria terminalis (BNST), a region critical to the integration of stress and reward pathways, and produces an impairment of extinction of cocaine-conditioned place preference (cocaine-CPP) independent of α2-AR signaling. Recent studies show yohimbine-induced drug-seeking behavior is attenuated by orexin receptor 1 (OX1R) antagonists. Moreover, yohimbine-induced cocaine-seeking behavior is BNST-dependent. Here, we investigated yohimbine-orexin interactions. Our results demonstrate yohimbine-induced depression of excitatory transmission in the BNST is unaffected by alpha1-AR and corticotropin-releasing factor receptor-1 (CRFR1) antagonists, but is (1) blocked by OxR antagonists and (2) absent in brain slices from orexin knockout mice. Although the actions of yohimbine were not mimicked by the norepinephrine transporter blocker reboxetine, they were by exogenously applied orexin A. We find that, as with yohimbine, orexin A depression of excitatory transmission in BNST is OX1R–dependent. Finally, we find these ex vivo effects are paralleled in vivo, as yohimbine-induced impairment of cocaine-CPP extinction is blocked by a systemically administered OX1R antagonist. These data highlight a new mechanism for orexin on excitatory anxiety circuits and demonstrate that some of the actions of yohimbine may be directly dependent upon orexin signaling and independent of norepinephrine and CRF in the BNST.  相似文献   
107.

The objective of the present study was to determine whether there is an association between pornography use and reported intimate partner violence (IPV) perpetration among a sample of soldiers in the US Army. The study was a secondary analysis of cross-sectional data collected from soldiers at a military installation in 2018 (n?=?9,052). IPV was defined as any self-reported perpetration of physical, sexual, or psychological abuse of an intimate partner. Multivariable negative binomial regressions were used to assess the association between pornography use and any lifetime perpetration of IPV, controlling for gender, age group, race/ethnicity, relationship status, educational status, military rank, hazardous drinking, depression, stimulant use, depressant use, and post-traumatic stress disorder. Of the population analyzed, 41% of soldiers reported any pornography use per week, and 9.6% reported perpetrating any form of IPV. Soldiers who reported pornography use had between a 1.72- and 3.56-fold greater likelihood of reporting any lifetime perpetration of IPV, controlling for covariates. Given the prevalence and detrimental effects of IPV, longitudinal studies should be designed to further understand predictors of IPV in military populations.

  相似文献   
108.
The Regional Coordinating Center for Hurricane Response (RCC) collaborated with the EXPORT Centers (Centers of Excellence in Partnerships for Community Outreach, Research on Health Disparities and Training) to rebuild, revitalize, and improve the health care infrastructure in the Gulf Coast states damaged by Hurricanes Katrina and Rita. This initiative aims to enhance the provision of health care by installing Electronic Health Records and Telepsychiatry systems throughout the Gulf Coast. Through the EXPORT Centers, the RCC plans to perform screening and surveillance projects within the communities and develop research projects focused on eliminating health disparities affecting underserved populations in the region. Another goal is to establish partnerships with EXPORT Centers, Community Health Centers, and other essential primary care practices in hurricane-ravaged communities. Through these partnerships, the overarching goal is to create a balanced health care system model that academic institutions can integrate into preventive care for emergency planning and research.  相似文献   
109.
OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance.  相似文献   
110.
目的 :观察银杏叶醇提取物对异烟肼和利福平肝毒性的保护作用及其机制探讨。方法 :分别测定肝损害组和银杏叶醇提取物大、小剂量组小鼠的血清谷丙转胺酶 (SGPT)、肝指数、肝匀浆丙二醛 (MDA)含量、肝微粒体P4 50和线粒体Ca2 ATP酶活性 ,以及肝病理检查 ,并与对照组比较。结果 :银杏叶醇提取物大、小剂量均可对抗异烟肼和利福平引起的MDA、SGPT、肝微粒体P4 50 的增高 (P <0 .0 5) ,以及对抗其引起的形态学改变 ;银杏叶醇提取物大剂量对抗其线粒体Ca2 ATP酶活性的降低。结论 :银杏叶醇提取物可对抗异烟肼和利福平所致肝毒性。  相似文献   
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