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In the USA, the Black Church is among the most important institutions in the Black community, offering numerous spiritual, social and health benefits. Yet, the presence of homonegativity in many Black Churches may mitigate those effects for gay Black youth. This research examines the role of the Church in the lives of gay and bisexual Black youth to understand how they reconcile any tension between their religious and sexual identities. Through interviews with pastors of Black churches (n = 21) and young Black men who have sex with men (n = 30), we explored homonegativity and young men’s experiences within the Black Church. Findings reveal that despite the prevalence of homonegativity within Black churches, religious involvement remains important for young men and many remain involved in non-affirming churches. The importance of the Church for young men stems from their significant involvement as youth and the integration of religion, family and community. Young men may not be able to leave their religious homes as readily as other gay youth given the cultural relevance of the Church. As a result, young men made attempts to conceal their sexuality in church to avoid shame and gossip and find opportunities to balance their sexuality and religiosity.  相似文献   
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Genotoxins, such as polycyclic aromatic compounds, are ubiquitous in urban and industrial environments. Our understanding of the role that these chemicals play in generating DNA sequence mutations is predominantly derived from laboratory studies with specific genotoxins or extracts of contaminants from environmental media. Most assays are not indicative of the germinal effects of exposure in situ to complex mixtures of common environmental mutagens. Using multilocus DNA fingerprinting, we found the mutation rate in herring gulls inhabiting a heavily industrialized urban harbor (Hamilton Harbour, Ontario) to be more than twice as high as three rural sites: Kent Island, Bay of Fundy; Chantry Island, Lake Huron; and Presqu'ile Provincial Park in Lake Ontario. Overall we found a mutation rate of 0.017 +/- 0.004 per offspring band in Hamilton, 0.006 +/- 0.002 at Kent Island, 0.002 +/- 0.002 from Chantry Island, and 0.004 +/- 0.002 from Presqu'ile Provincial Park. The mutation rate from the rural sites (pooled) was significantly lower than the rate observed in Hamilton Harbour (Fisher's exact test, two-tailed; P = 0.0006). These minisatellite DNA mutations may be important biomarkers for heritable genetic changes resulting from in situ exposure to environmental genotoxins in a free-living vertebrate species.  相似文献   
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The origin and nature of osteoclast-like multinucleated giant cells (OMGCs), in extraskeletal neoplasms, is uncertain. The ultrastructure, antigenic phenotype and function of OMGCsm in a breast carcinoma were studied in order to clarify the relationship between OMGCs, osteoclasts and other cells of the mononuclear phagocyte system (MPS). OMGCs resorbed cortical bone in a manner similar to osteoclasts. However, unlike osteoclasts, OMGCs did not possess a ruffled border or clear zone, and expressed HLA-DR and Fc receptors and CD14, CD16, CD18 and CD11 (p150,95) antigens. In addition, OMGCs failed to respond morphologically to calcitonin and were directly stimulated by parathyroid hormone (PTH) to increase bone resorption. These findings suggest that OMGCs are a specific type of macrophage polykaryon distinct from both osteoclasts and other types of inflammatory polykaryon. Occasional smaller (20-25 microns) macrophage-like cells were also associated with resorption pits. Bone resorption by OMGCs isolated from the breast indicates that a cell of the MPS can be transplanted to a new tissue location and perform a highly specialised function appropriate to an MPS cell of that tissue (i.e. the osteoclast). PTH stimulation of bone resorption by OMGCs suggests that PTH or a PTH-like protein, may be involved in the bone resorption and consequent hypercalcaemia associated with metastatic breast cancer.  相似文献   
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Background : Severe odontogenic infections are serious potentially lethal conditions. Following the death of a patient in the authors' institution this study was initiated to determine the risk factors, management and outcome of a consecutive series of patients.
Methods : All patients admitted to the Royal Adelaide Hospital under the care of the Oral and Maxillofacial Surgery Unit with odontogenic infections in calendar year 2003 were investigated. Detailed information relative to their pre-presentation history, surgical and anaesthetic management and outcome was obtained and analysed.
Results : Forty-eight patients, 32M, 16F, average age 34.5, range 19 to 88 years were treated. All presented with pain and swelling, with 21 (44 per cent) having trismus. Forty-four (92 per cent) were as a result of dental neglect and four (8 per cent) were regular dental patients having endodontic treatment which failed. Of those known to have been treated prior to presentation, most had been on antibiotics. Most patients had aggressive surgical treatment with extraction, surgical drainage, high dose intravenous antibiotics and rehydration. The hospital stay was 3.3 (range 1–16) days. Patients requiring prolonged intubation and high dependency or intensive care (40 per cent) had longer hospitalization. No patient died and all fully recovered.
Conclusion : Severe odontogenic infections are a serious risk to the patient's health and life. Management is primarily surgical with skilled anaesthetic airway management. Antibiotics are required in high intravenous doses as an adjunct and not as a primary treatment.  相似文献   
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Peptide-targeted alpha-therapy with 7.4 MBq of (212)Pb-[1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-ReO-[Cys(3,4,10),d-Phe(7),Arg(11)]alpha-MSH(3-13) ((212)Pb-DOTA-Re(Arg(11))CCMSH) cured 45% of B16/F1 murine melanoma-bearing C57 mice in a 120-d study, highlighting its melanoma treatment potential. However, there is a need to develop an imaging surrogate for patient-specific dosimetry and to monitor the tumor response to (212)Pb-DOTA-Re(Arg(11))CCMSH therapy. The purpose of this study was to evaluate the potential of (203)Pb-DOTA-Re(Arg(11))CCMSH as a matched-pair SPECT agent for (212)Pb-DOTA-Re(Arg(11))CCMSH. METHODS: DOTA-Re(Arg(11))CCMSH was labeled with (203)Pb in 0.5 M NH(4)OAc buffer at pH 5.4. The internalization and efflux of (203)Pb-DOTA-Re(Arg(11))CCMSH were determined in B16/F1 melanoma cells. The pharmacokinetics of (203)Pb-DOTA-Re(Arg(11))CCMSH was examined in B16/F1 melanoma-bearing C57 mice. A micro-SPECT/CT study was performed with (203)Pb-DOTA-Re(Arg(11))CCMSH in a B16/F1 melanoma-bearing C57 mouse at 2 h after injection. RESULTS: (203)Pb-DOTA-Re(Arg(11))CCMSH was easily prepared in NH(4)OAc buffer and completely separated from the excess nonradiolabeled peptide by reversed-phase high-performance liquid chromatography (RP-HPLC). (203)Pb-DOTA-Re(Arg(11))CCMSH displayed fast internalization and extended retention in B16/F1 cells. Approximately 73% of (203)Pb-DOTA-Re(Arg(11))CCMSH activity internalized after a 20-min incubation at 25 degrees C. After incubation of the cells in culture medium for 20 min, 78% of internalized activity remained in the cells. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a biodistribution pattern similar to that of (212)Pb-DOTA-Re(Arg(11))CCMSH in B16/F1 melanoma-bearing mice. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a peak tumor uptake of 12.00+/-3.20 percentage injected dose per gram (%ID/g) at 1 h after injection. The tumor uptake gradually decreased to 3.43+/-1.12 %ID/g at 48 h after injection. (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited a peak tumor-to-kidney uptake ratio of 1.53 at 2 h after injection. The absorbed doses to the tumor and kidneys were 4.32 and 4.35 Gy, respectively, per 37 MBq. Whole-body clearance of (203)Pb-DOTA-Re(Arg(11))CCMSH was fast, with approximately 89% of the injected activity cleared through the urinary system by 2 h after injection. (203)Pb showed 1.6-mm SPECT resolution, which was comparable to (99m)Tc. Melanoma lesions were visualized through SPECT/CT images of (203)Pb-DOTA-Re(Arg(11))CCMSH at 2 h after injection. CONCLUSION: (203)Pb-DOTA-Re(Arg(11))CCMSH exhibited favorable pharmacokinetic and tumor imaging properties, highlighting its potential as a matched-pair SPECT agent for (212)Pb-DOTA-Re(Arg(11))CCMSH melanoma treatment.  相似文献   
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Coagulation screening before epidural analgesia in pre-eclampsia   总被引:1,自引:0,他引:1  
A questionnaire survey of current practice at a small cross-section of obstetric units, covering 22% of all United Kingdom deliveries, revealed a marked lack of standard practice regarding requests for coagulation screens on pre-eclamptic patients who require epidural procedures. A retrospective audit was therefore carried out on 434 coagulation screens requested for pre-eclamptic patients in whom epidural analgesia might have been considered. Borderline abnormalities of coagulation were found in only 10 patients (2%). Platelet counts of less than 150 x 10(9)/litre were present in 28% of cases. 'Significant' thrombocytopenia (less than 100 x 10(9)/litre) and all coagulation abnormalities were only encountered in severe pre-eclampsia (diastolic blood pressure of greater than 110 mmHg and proteinuria of + + or greater). Furthermore, coagulation abnormality was always associated with a reduced platelet count (mean, 97 x 10(9)/litre). This study would therefore support anaesthetic practice which restricted any requests for coagulation testing to severe pre-eclamptic patients only. For these patients first line testing could be limited to a platelet count.  相似文献   
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Background: Although the activation-induced intracellular Ca2+ signal is disrupted by sensory neuron injury, the contribution of specific Ca2+ channel subtypes is unknown.

Methods: Transients in dissociated rat dorsal root ganglion neurons were recorded using fura-2 microfluorometry. Neurons from control rats and from neuropathic animals after spinal nerve ligation were activated either by elevated bath K+ or by field stimulation. Transients were compared before and after application of selective blockers of voltage-activated Ca2+ channel subtypes.

Results: Transient amplitude and area were decreased by blockade of the L-type channel, particularly during sustained K+ stimulation. Significant contributions to the Ca2+ transient are attributable to the N-, P/Q-, and R-type channels, especially in small neurons. Results for T-type blockade varied widely between cells. After injury, transients lost sensitivity to N-type and R-type blockers in axotomized small neurons, whereas adjacent small neurons showed decreased responses to blockers of R-type channels. Axotomized large neurons were less sensitive to blockade of N- and P/Q-type channels. After injury, neurons adjacent to axotomy show decreased sensitivity of K+-induced transients to L-type blockade but increased sensitivity during field stimulation.  相似文献   

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