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The 8th Conference of the British Psychosocial Oncology Group was held in London on 9–10 December 1991 and attracted over 120 participants. The conference was extended from its usual one day format to one and a half days, to allow more time for both a formal and informal exchange of ideas. Eight invited speakers participated, but proferred papers and posters remained an important focus of the meeting. This is the largest annual conference in Britain for professionals working in psychosocial oncology and an important forum for the presentation of research. As in previous years, the conference attracted a number of newcomers, indicating the continued expansion of this field of research. A number of topical issues were presented in keynote papers by invited speakers. New work in cancer prevention and the associated areas of counselling families at risk and ethical issues, formed one symposium. Communication skills and relevant training needs in paediatric and adult oncology were an important theme of the conference and intervention studies formed the third main topic.  相似文献   
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Although sexual assault by workplace personnel is widely viewed as a type of sexual harassment, little is known about whether these overlapping constructs may possess some unique characteristics. This article compares the theoretical antecedents and consequences of sexual assault by workplace personnel and other types of sexual harassment among 22,372 women employed in the U.S. military. Path analysis revealed that low sociocultural and organizational power are associated with an increased likelihood of both types of victimization. Organizational climate and job gender context are directly associated with sexual harassment but are only indirectly associated with sexual assault by workplace personnel. Both types of victimization are associated with a variety of negative outcomes, but the pattern of negative consequences differs.  相似文献   
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The marginal zone macrophages of the spleen are implicated in the clearance of polysaccharides, but underlying mechanisms need to be pinpointed. SIGN-R1 is one of five recently identified mouse genes that are homologous to human DC-SIGN and encode a single, external, C-terminal C-type lectin domain. We find that a polyclonal antibody to a specific SIGN-R1 peptide reacts primarily and strongly with a subset of macrophages in the marginal zone of spleen and lymph node medulla. In both sites, SIGN-R1 exists primarily in an aggregated form, resistant to dissociation into monomers upon boiling in SDS under reducing conditions. Upon transfection into three different cell lines, high-mol.-wt forms bearing SIGN-R1 are expressed, as well as reactivity with ER-TR9, a mAb previously described to react selectively with marginal zone macrophages. SIGN-R1-expressing macrophages preferentially sequester dextrans following i.v. injection. Likewise, when phagocytic cells are enriched from spleen and tested in culture, dextran is selectively endocytosed by a subset of very large SIGN-R1(+) cells representing approximately 5% of total released macrophages. Uptake of FITC-dextran by these macrophages in vivo and in vitro is blocked by ER-TR9 and polyclonal anti-SIGN-R1 antibodies. Following transfection with SIGN-R1, cell lines become competent to endocytose dextrans. The dextran localizes primarily to compartments lacking transferrin receptor and the LAMP-1 CD107a panlysosomal antigen. Therefore, SIGN-R1 mediates the uptake of dextran polysaccharides, and it is predominantly expressed in the macrophages of the splenic marginal zone and lymph node medulla.  相似文献   
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Leukodystrophies are a heterogeneous group of heritable disorders characterized by abnormal brain white matter signal on magnetic resonance imaging (MRI) and primary involvement of the cellular components of myelin. Previous estimates suggest the incidence of leukodystrophies as a whole to be 1 in 7,000 individuals, however the frequency of specific diagnoses relative to others has not been described. Next generation sequencing approaches offer the opportunity to redefine our understanding of the relative frequency of different leukodystrophies. We assessed the relative frequency of all 30 leukodystrophies (associated with 55 genes) in more than 49,000 exomes. We identified a relatively high frequency of disorders previously thought of as very rare, including Aicardi Goutières Syndrome, TUBB4A‐related leukodystrophy, Peroxisomal biogenesis disorders, POLR3‐related Leukodystrophy, Vanishing White Matter, and Pelizaeus‐Merzbacher Disease. Despite the relative frequency of these conditions, carrier‐screening laboratories regularly test only 20 of the 55 leukodystrophy‐related genes, and do not test at all, or test only one or a few, genes for some of the higher frequency disorders. Relative frequency of leukodystrophies previously considered very rare suggests these disorders may benefit from expanded carrier screening.  相似文献   
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Hypoxic proliferation of pulmonary arterial smooth muscle cells (PASMC) is mitogen dependent, but the signaling pathways mediating hypoxia-induced cell growth are not well understood. We investigated hypoxic proliferation in primary cultures from porcine pulmonary artery smooth muscle. The cells were grown in medium with or without platelet-derived growth factor (PDGF)-B, a potent smooth muscle cell mitogen. Hypoxia induced upregulation of PDGF receptor-beta expression, the primary receptor for PDGF-B. However, PDGF-B-mediated hypoxic enhancement of proliferation was abolished by pertussis toxin, indicating (1) involvement of heterotrimeric Galpha i proteins and (2) minimal effect of increased PDGF receptor expression in hypoxic enhancement of proliferation. We treated PASMC with labeled, nonhydrolyzable analogs of GTP to determine directly if GTP binding proteins were activated by hypoxia in PASMC. We show that hypoxia stimulates GTP incorporation in PASMC both in the presence and absence of PDGF-B. Serum-starved PASMC are able to increase their incorporation of GTP after only 10 min of hypoxia, and this response is not pertussis toxin sensitive. In serum-starved PASMC, we show that hypoxia stimulates incorporation of GTP into a 44-kD protein. The results show that heterotrimeric G proteins are involved in hypoxia-induced signaling in pulmonary vascular smooth muscle cells.  相似文献   
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The management of choledocholithiasis in children and teenagers is often a two-procedure process with laparoscopic cholecystectomy (LC) and either pre- or post-operative endoscopic retrograde cholangiopancreatography (ERCP). The addition of laparoscopic common bile duct exploration (LCBDE) during LC can provide definitive treatment for choledocholithiasis during a single anesthetic event. In an effort to minimize sedation and radiation exposure from fluoroscopy, we have employed dilating balloons via a transcystic approach to stretch the sphincter of Oddi with subsequent ductal flushing. We describe the technique of balloon sphincteroplasty as a straightforward adjunct within the pediatric surgeon's skill set to manage choledocholithiasis during LC and our clinical experience.  相似文献   
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The excellent temporal resolution and advanced spatial resolution of magnetoencephalography (MEG) makes it an excellent tool to study the neural dynamics underlying cognitive processes in the developing brain. Nonetheless, a number of challenges exist when using MEG to image infant populations. There is a persistent belief that collecting MEG data with infants presents a number of limitations and challenges that are difficult to overcome. Due to this notion, many researchers either avoid conducting infant MEG research or believe that, in order to collect high‐quality data, they must impose limiting restrictions on the infant or the experimental paradigm. In this article, we discuss the various challenges unique to imaging awake infants and young children with MEG, and share general best‐practice guidelines and recommendations for data collection, acquisition, preprocessing, and analysis. The current article is focused on methodology that allows investigators to test the sensory, perceptual, and cognitive capacities of awake and moving infants. We believe that such methodology opens the pathway for using MEG to provide mechanistic explanations for the complex behavior observed in awake, sentient, and dynamically interacting infants, thus addressing core topics in developmental cognitive neuroscience.  相似文献   
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