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991.
992.
Men who have sex with men (MSM) remain the most severely affected risk group in the US HIV/AIDS epidemic. One-third to two-thirds of HIV transmissions among MSM are estimated to come from primary sex partners. Couples HIV testing and counseling (CHTC), in which two individuals receive pre-test counseling, HIV testing and post-test prevention planning together, has been adapted for male couples in the USA, and is now available in more than 30 cities. Previous studies have demonstrated high levels of willingness to use CHTC among MSM, but to date no studies have explored this among Latino MSM (LMSM). To examine the willingness to use CHTC among and further cultural adaptation needed for LMSM, focus group discussions were held with men who self-identified as Latino, were in a relationship with another man, and resided in Seattle. Willingness to use CHTC was high. Participants reported that CHTC could strengthen and validate their relationships, help mitigate stigma, and provide a forum for support, protection, and information sharing. Barriers to CHTC use included fears of rejection, loneliness, and relationship dissolution, and concerns around deportation and financial burden. The high levels of reported willingness to use CHTC among this sample of LMSM point to the potential for CHTC to be further adapted to provide dyadic HIV testing services for LMSM.  相似文献   
993.
The study aimed to assess the psychometric properties of the Indigenous Risk Impact Screen (IRIS) as a screening instrument for determining (i) the presence of alcohol and drug and mental health risk in Indigenous adult Australians and (ii) the cut-off scores that discriminate most effectively between the presence and absence of risk. A cross-sectional survey was used in clinical and non-clinical Indigenous and non-Indigenous services across Queensland Australia. A total of 175 Aboriginal and Torres Strait Islander people from urban, rural, regional and remote locations in Queensland took part in the study. Measures included the Indigenous Risk Impact Screen (IRIS), the Severity of Dependence Scale (SDS), the Alcohol Use Disorders Identification Test (AUDIT) and the Leeds Dependence Questionnaire (LDQ). Additional Mental Health measures included the Depression Anxiety and Stress Scale (DASS-21) and the Self-Report Questionnaire (SRQ). Principle axis factoring analysis of the IRIS revealed two factors corresponding with (i) alcohol and drug and (ii) mental health. The IRIS alcohol and drug and mental health subscales demonstrated good convergent validity with other well-established screening instruments and both subscales showed high internal consistency. A receiver operating characteristics (ROC) curve analysis was used to generate cut-offs for the two subscales and t-tests validated the utility of these cut-offs for determining risky levels of drinking. The study validated statistically the utility of the IRIS as a screen for alcohol and drug and mental health risk. The instrument is therefore recommended as a brief screening instrument for Aboriginal and Torres Strait Islander people. [Schlesinger CM, Ober C, McCarthy MM, Watson JD, Seinen A. The development and validation of the Indigenous Risk Impact Screen (IRIS): a 13-item screening instrument for alcohol and drug and mental health risk. Drug Alcohol Rev 2007;26:109 - 117]  相似文献   
994.
The recent anthrax outbreak among injecting drug users (IDUs) in Europe has highlighted an ongoing problem with severe illness resulting from spore-forming bacteria in IDUs. We collated the numbers of cases of 4 bacterial illnesses (botulism, tetanus, Clostridium novyi, and anthrax) in European IDUs for 2000 to 2009 and calculated population rates. Six countries reported 367 cases; rates varied from 0.03 to 7.54 per million people. Most cases (92%) were reported from 3 neighboring countries: Ireland, Norway, and the United Kingdom. This geographic variation needs investigation.  相似文献   
995.

Background and purpose:

Nitroxyl (HNO) is emerging as an important regulator of vascular tone as it is potentially produced endogenously and dilates conduit and resistance arteries. This study investigates the contribution of endogenous HNO to endothelium-dependent relaxation and hyperpolarization in resistance arteries.

Experimental approach:

Rat and mouse mesenteric arteries were mounted in small vessel myographs for isometric force and smooth muscle membrane potential recording.

Key results:

Vasorelaxation to the HNO donor, Angeli''s salt, was attenuated in both species by the soluble guanylate cyclase inhibitor (ODQ, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one), the voltage-dependent K+ channel inhibitor, 4-aminopyridine (4-AP) and the HNO scavenger, l-cysteine. In mouse mesenteric arteries, nitric oxide (NO) synthase inhibition (with l-NAME, Nω-Nitro-L-arginine methyl ester) markedly attenuated acetylcholine (ACh)-mediated relaxation. Scavenging the uncharged form of NO (NO) with hydroxocobalamin (HXC) or HNO with l-cysteine, or 4-AP decreased the sensitivity to ACh, and a combination of HXC and l-cysteine reduced ACh-mediated relaxation, as did l-NAME alone. ACh-induced hyperpolarizations were significantly attenuated by 4-AP alone and in combination with l-NAME. In rat mesenteric arteries, blocking the effects of endothelium-derived hyperpolarizing factor (EDHF) (charybdotoxin and apamin) decreased ACh-mediated relaxation 10-fold and unmasked a NO-dependent component, mediated equally by HNO and NO, as HXC and l-cysteine in combination now abolished vasorelaxation to ACh. Furthermore, ACh-evoked hyperpolarizations, resistant to EDHF inhibition, were virtually abolished by 4-AP.

Conclusions and implications:

The factors contributing to vasorelaxation in mouse and rat mesenteric arteries are NO = HNO > EDHF and EDHF > HNO = NO respectively. This study identified HNO as an endothelium-derived relaxing and hyperpolarizing factor in resistance vessels.British Journal of Pharmacology (2009) 157, 540–550; doi:10.1111/j.1476-5381.2009.00150.x; published online 26 March 2009This article is commented on by Martin, pp. 537–539 of this issue and is part of a themed section on Endothelium in Pharmacology. For a list of all articles in this section see the end of this paper, or visit: http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009  相似文献   
996.
Objective To assess whether an inflatable obstetric belt, synchronised to apply uniform fundal pressure during a uterine contraction, reduces operative delivery rates when used in the second stage of labour.
Design Randomised controlled trial.
Methods Five hundred nulliparae with a singleton cephalic pregnancy at term and with an epidural in labour were recruited during the first stage and randomised at full dilatation. Standard care involved one hour passive second stage and one hour active pushing after which instrumental delivery was performed if delivery was not imminent. Those randomised to the belt group, in addition to standard care, had the inflatable obstetric belt for the whole second stage of labour.
Main outcome measure Mode of delivery.
Results One hundred and eleven of the 260 women in the belt group (42.7%) compared with 94 of the 240 in the control group (39.2%) had a spontaneous vertex delivery (   P = 0.423  ). The lift-out instrumental delivery rate was similar between the two groups: 108 belts (41.5%), compared with 101 controls (42.1%) (   P = 0.902  ), whereas rotational instrumental deliveries in the belt group were 26 belts (10%) compared with 36 controls (15%) (   P = 0.09  ). Fifteen women (5.8%) in the belt group and nine women (34%) in the control group had a caesarean section in the second stage (   P = 0.292  ). An intact perineum was more likely in the belt group (16.5% compared with 9–6%,   P = 0.022  ) as was a third degree tear (6.5% compared with 0.4%,   P = 0.001  ).
Conclusion The inflatable obstetric belt did not significantly reduce operative delivery rates when used in this clinical setting in the second stage of labour.  相似文献   
997.
998.
RATIONALE AND OBJECTIVES: The study was designed to evaluate a new digitizing device, the iView (Maxxvision, LLC, Gainesville, FL), which aims to replace the magnifying glass in mammography with real-time film digitization, display, and processing. MATERIALS AND METHODS: A receiver operating characteristic (ROC) experiment was performed with 5 certified mammographers and 114 mammograms that were read with and without the iView. A satisfaction survey was also conducted on the system's features and usefulness. RESULTS: Data analysis suggested that (1) Cancer sensitivity could improve with the use of the iView system. ROC area differences showed improvements from 2% to 24% although these were not always statistically significant. At a false positive rate of 0.2, the true positive rate increased up to 60% depending on the set of cases and the observer's experience. (2) Specificity could also be improved. At a true positive rate of 0.9, the false positive rate decreased by as much as 55%. (3) Most observers felt more confident in their decisions when using the iView, although the prototype's ergonomic problems did not allow full utilization of its capabilities. CONCLUSION: Our pilot clinical study showed that the iView has the potential to improve mammogram interpretation. In addition, the system could broaden the applicability of electronic information and provide wider access to digital technology through a relatively simple and cost-effective approach. Observers recommended several improvements in the ergonomics and default display of the system that are currently implemented by the company. A larger clinical study of the improved system is necessary to clearly demonstrate its clinical value for mammography.  相似文献   
999.
Global evidence demonstrates that adherence to the Baby Friendly Initiative (BFI) has a positive impact on multiple child health outcomes, including breastfeeding initiation and duration up to 1 year post‐partum. However, it is currently unclear whether these findings extend to specific countries with resource‐rich environments. This mixed‐methods systematic review aims to (a) examine the impact of BFI implementation (hospital and community) on maternal and infant health outcomes in the United Kingdom (UK) and (b) explore the experiences and views of women receiving BFI‐compliant care in the UK. Two authors independently extracted data including study design, participants, and results. There is no UK data available relating to wider maternal or infant health outcomes. Two quantitative studies indicate that Baby Friendly Hospital Initiative implementation has a positive impact on breastfeeding outcomes up to 1 week post‐partum but this is not sustained. There was also some evidence for the positive impact of individual steps of Baby Friendly Community Initiative (n = 3) on breastfeeding up to 8 weeks post‐partum. Future work is needed to confirm whether BFI (hospital and community) is effective in supporting longer term breastfeeding and wider maternal and infant health outcomes in the UK. A meta‐synthesis of five qualitative studies found that support from health professionals is highly influential to women's experiences of BFI‐compliant care, but current delivery of BFI may promote unrealistic expectations of breastfeeding, not meet women's individual needs, and foster negative emotional experiences. These findings reinforce conclusions that the current approach to BFI needs to be situationally modified in resource‐rich settings.  相似文献   
1000.

Purpose

Exercise has been shown to reduce fatigue during cancer treatment. Hypothesized mechanisms include inflammatory pathways. Therefore, we investigated effects of exercise on markers of inflammation in breast cancer patients during adjuvant chemotherapy.

Methods

We pooled data from two randomized controlled exercise intervention trials with breast cancer patients during adjuvant chemotherapy (n = 130), which had previously shown beneficial effects of exercise on fatigue. Exercise comprised a 12-week resistance training (BEATE study) or an 18-week combined resistance and aerobic training (PACT study). Serum IL-6, IL-1ra, and the IL-6/IL-1ra ratio were quantified at baseline, mid-intervention, post-intervention, and 6–9 months post-baseline.

Results

Mixed effect models showed significant increases in IL-6 and IL-6/IL-1ra ratio during chemotherapy and decreases afterwards. Differences between exercise and control group were not significant at any time point. Changes in total cancer-related fatigue were significantly correlated with changes in IL-6/IL-1ra ratio (partial correlation r = 0.23) and IL-6 (r = 0.21), and changes in physical cancer-related fatigue with changes in IL-6/IL-1ra ratio (r = 0.21).

Conclusions

Changes in fatigue were slightly correlated with changes in inflammatory markers, and there was a strong inflammatory response to adjuvant chemotherapy. The supervised exercise training did not counteract this increase in inflammation, suggesting that beneficial effects of exercise on fatigue during adjuvant chemotherapy for breast cancer are not essentially mediated by IL-6, IL-1ra, or the IL-6/IL-1ra ratio.
  相似文献   
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