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101.
During reproduction, male vertebrates may exhibit a continuum of interactions between sex and adrenal steroids during stressful events, the outcome of which may be important in either reducing or promoting male reproductive success. We studied adult male green turtles (Chelonia mydas) to examine if they altered plasma corticosterone (CORT) and androgen levels in response to a standardized capture/restraint stressor as potential mechanisms to maintain reproductive activity during stressful events. At the population level, we found that migrant breeding males had a significantly smaller CORT response to the capture/restraint stressor compared to nonbreeding males and that this decreased response coincided with the generally poorer body condition of migrant breeders. In contrast, plasma androgen levels decreased significantly in response to the capture/restraint stressor in migrant breeding males, but not in nonbreeding and pre-migrant breeding males. For individual migrant breeding males, the magnitude of their CORT and androgen responses to the capture/restraint stressor was highly correlated with their body condition and body length, respectively. Our results demonstrate that male green turtles exhibit complex interactions in their endocrine responses to a capture/restraint stressor and that variation in these interactions is associated with differences in males' reproductive, energetic, and physical state. We hypothesize that interplay between physical status and plasma hormone responses to stressors could have important consequences for male green turtle reproduction.  相似文献   
102.
OBJECTIVE: To assess the uptake of and adherence to nevirapine to prevent mother-to-child HIV transmission among women of unknown HIV serostatus presenting in labor. We also assessed preliminary efficacy of the approach. DESIGN: Women of unknown HIV serostatus presenting in labor were offered single-dose nevirapine in a prospective cohort study. Two additional contemporaneous comparison populations were also studied. METHODS: We measured uptake by counting the number of women that accepted enrollment when offered. We measured adherence with cord blood nevirapine assay. We measured preliminary efficacy with HIV DNA polymerase chain reaction of infant blood spots at 4-6 weeks of life. RESULTS: Of 1591 women approached in labor, 634 (40%) took up the intervention and received nevirapine, of whom 185 (29%) were HIV infected. Of 179 cord blood specimens from HIV-exposed infants that could be evaluated, 178 (99.4%) had nevirapine detected. This was higher than the 73 of 98 (74%) adherence rate observed in a comparison cohort in which women self-administered nevirapine before presenting to the labor ward (P < 0.001). Of 145 available infant specimens, 17 (11.7%) showed evidence of infection at 4-6 weeks, compared with 12 of 60 (20%) infants born immediately prior to study commencement whose HIV-infected mothers did not receive nevirapine (P < 0.05). CONCLUSIONS: Nevirapine without HIV testing upon presentation in labor was accepted by two-fifths of women. Because therapy is directly observed, adherence is nearly perfect. Labor ward dosing to enhance nevirapine coverage should be considered as an adjunct to antenatal nevirapine administration for prevention of mother-to-child transmission of HIV.  相似文献   
103.
A growing body of research evidence shows that Twelve Step Group (TSG) attendance confers a consistent moderate beneficial effect on substance use. Clinicians potentially represent a major referral pathway to TSG. This qualitative study aimed to explore staff perceptions of the barriers to Narcotics Anonymous (NA) group attendance in a population receiving drug treatment, and potential strategies to increase attendance. A cross-sectional survey of substance misuse treatment professionals was conducted between January and April 2012 in Birmingham, England. Fifty-eight members of staff working within statutory community drug treatment teams were interviewed using qualitative research methods. The overarching themes within the staff accounts are described and the importance of these themes explored. Perceived objections to core elements of the 12 step programme (religious nature of the programme, powerlessness, surrender, desire to stop using drugs) were major obstacles to recommending NA attendance. However, a perception that the client would object to any form of group process, and concerns about risk both to the client and the TSG members were also important. Increased education about TSG practices and procedures was a commonly cited strategy for increasing levels of TSG referral, and in particular ensuring that clinicians attend open meetings themselves. An increased understanding and familiarity with the process and principles of TSGs may be necessary to increase promotion of TSG within drug treatment services in line with recent national policy promoting recovery from drug use.  相似文献   
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BACKGROUND/AIMS: The role of cytotoxic T lymphocytes (CTL) in limiting viral replication and producing hepatocellular injury in patients with chronic hepatitis C virus (HCV) infection is controversial. METHODS: Intrahepatic and peripheral blood HCV-specific CTL activity against the entire HCV polyprotein was assessed in 26 patients. CTL responses were assessed after effector lymphocytes were re-stimulated for 6 days in vitro using HCV-vaccinia virus-infected autologous cells expressing HCV antigens. Serum and hepatic viral loads were measured and immunohistochemistry for CD3 and CD8 was performed to localise and enumerate effector cells in liver. RESULTS: A positive CTL response was detected in 39/52 (75%) of assays conducted with intrahepatic mononuclear cells and 21/52 (40%) of peripheral blood assays (P<0.001). The presence of an intrahepatic CTL response was associated with low hepatic viral load (P=0.004). Hepatic lobular infiltration by CD8(+)T cells correlated weakly with serum alanine aminotransferase levels (r=0.42, P=0.04) and no relationship was demonstrated between CTL activity and histological evidence of liver damage. CONCLUSIONS: HCV-specific CTL activity is found more commonly in liver than in blood. An inverse relationship between CTL responses and viral load supports the hypothesis that HCV-specific CTL limit viral replication in patients with chronic HCV infection.  相似文献   
106.
Abstract: Aims/Background: One function of Kupffer cells is the phagocytosis of nonviable hepatocytes. Our aims were to develop a model for phagocytosis of damaged hepatocytes by rat Kupffer cells in vitro, and to characterise prostaglandin E2 (PGE2), prostacyclin (PGI), and tumour necrosis factor-α (TNF) production in this model. Methods: Kupffer cells were incubated alone or with damaged hepatocytes for up to 18 h, then washed and cultured for up to 66 h. To compare mediator responses produced during inert particle phagocytosis, Kupffer cells were also incubated with latex beads. Results: Phagocytic uptake of hepatocyte debris was confirmed in at least 50% of Kupffer cells. A dissociation between TNF and PGI responses was found for both latex beads and damaged hepatocytes, such that a TNF secretory response was not triggered by either stimulus whereas PGI production was increased for both. Although phagocytosis of beads increased PGE2 production, phagocytosis of hepatocytes did not. Conclusions: Phagocytosis of damaged hepatocytes by Kupffer cells results in the production of PGI but not PGE2 or TNF.  相似文献   
107.
Rapid mortality surveillance is critical for state emergency preparedness. To enhance timeliness during the 2009–2010 influenza A H1N1 pandemic, the Ohio Department of Health activated a drop-down menu within Ohio’s Electronic Death Registration System for reporting of pneumonia- or influenza-related deaths approximately 5 days postmortem. We used International Classification of Diseases—Tenth Revision (ICD-10) codes, available 2–3 months postmortem as the standard, and assessed their agreement with drop-down-menu codes for pneumonia- or influenza-related deaths. Among 56 660 Ohio deaths during September 2009–March 2010, agreement was 97.9% for pneumonia (κ = 0.85) and 99.9% for influenza (κ = 0.79). Sensitivity was 80.2% for pneumonia and 73.9% for influenza. Drop-down menu coding enhanced timeliness while maintaining high agreement with ICD-10 codes.  相似文献   
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PURPOSE

The purpose of this study was to explore the perceptions and experiences of health care clinicians working in multidisciplinary teams that include specialist heart failure nurses when caring for the management of heart failure patients.

METHODS

We used a qualitative in-depth interview study nested in a broader ethnographic study of unplanned admissions in heart failure patients (HoldFAST). We interviewed 24 clinicians across primary, secondary, and community care in 3 locations in the Midlands, South Central, and South West of England.

RESULTS

Within a framework of the role and contribution of the heart failure specialist nurse, our study identified 2 thematic areas that the clinicians agreed still represent particular challenges when working with heart failure patients. The first was communication with patients, in particular explaining the diagnosis and helping patients to understand the condition. The participants recognized that such communication was most effective when they had a long-term relationship with patients and families and that the specialist nurse played an important part in achieving this relationship. The second was communication within the team. Multidisciplinary input was especially needed because of the complexity of many patients and issues around medications, and the participants believed the specialist nurse may facilitate team communication.

CONCLUSIONS

The study highlights the role of specialist heart failure nurses in delivering education tailored to patients and facilitating better liaison among all clinicians, particularly when dealing with the management of comorbidities and drug regimens. The way in which specialist nurses were able to be caseworkers for their patients was perceived as a method of ensuring coordination and continuity of care.  相似文献   
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