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991.
Aims To conduct a randomized, controlled trial of abstinence‐contingent recovery housing delivered with or without intensive day treatment among individuals exiting residential opioid detoxification. Design Random assignment to one of three conditions: recovery housing alone (RH), abstinence‐contingent recovery housing with reinforcement‐based treatment RBT (RH + RBT) or usual care (UC). RH and RH + RBT participants received 12 weeks of paid recovery housing contingent upon drug abstinence. RH + RBT participants also received 26 weeks of RBT, initiated concurrently with recovery housing. Assessments were conducted at 1, 3 and 6 months after treatment enrollment. Setting Out‐patient drug‐free substance abuse treatment program in Baltimore, Maryland. Participants Patients (n = 243) who completed medication‐assisted opioid detoxification. Measurements Primary outcome was drug abstinence (opioid‐ and cocaine‐negative urine and no self‐reported opioid or cocaine use in the previous 30 days). Secondary outcomes included abstinence at all time‐points (1, 3 and 6 months), days in recovery housing and employment. Findings Overall rates of drug abstinence were 50% for RH + RBT, 37% for RH and 13% for UC (P < 0.001). At 6 months, RH + RBT participants remained more likely to meet abstinence criteria than UC participants (37% versus 20%, P = 0.016). Length of stay in recovery housing mediated abstinence outcomes and was longer in RH + RBT (49.5 days) than in RH (32.2 days; P < 0.002). Conclusions Abstinence‐contingent recovery housing improves abstinence in opioid‐dependent adults following medication‐assisted detoxification. The addition of intensive ‘reinforcement‐based treatment’ behavioural counseling further improves treatment outcomes, in part by promoting longer recovery house stays.  相似文献   
992.
A fifty-year-old male had an echocardiogram for an abnormal electrocardiogram; it revealed a left ventricular mass. A cardiac catheterization revealed normal coronary arteries and a fine tumor blush of the cardiac tumor with feeding arteries from the circumflex as well as the second diagonal coronary vessels. Due to increased risk of embolization, he underwent surgery via a transatrial approach and a 1.5 cm cavernous-capillary hemangioma was removed from the base of the posteromedial papillary muscle. Primary tumors of the heart are rare, and the symptoms and signs depend on the location and size of the tumor. Coronary angiography remains an integral part in the evaluation of cardiac tumors and often can reveal a characteristic 'tumor blush.' The natural history of the tumor is unpredictable and excision of the tumor remains the treatment of choice. We present a rare case of characteristic angiographic tumor blush of a left ventricular cardiac hemangioma with feeding arteries from both the left anterior descending as well as the circumflex arteries. This rare two-system supply was due to the intracavitary location of the hemangioma, and fortunately did not pose any excessive difficulty in mobilization and excision during surgery.  相似文献   
993.
BackgroundCumulative dose-dependent nonischemic cardiomyopathy (NICM) remains a significant risk with the use of some chemotherapeutic agents. In this context, omega-3 polyunsaturated fatty acids (PUFA) have been investigated for their cardioprotective potential in rodent and in vitro models of anthracycline toxicity, with conflicting results. This study evaluated prophylactic omega-3 PUFA supplementation in a large-animal model of anthracycline-induced NICM.Methods and ResultsMerino sheep were randomized to oral drenching with omega-3 PUFA (fish oil; n = 8) or olive oil placebo (n = 9) 3 weeks before commencing repeated intracoronary infusions of doxorubicin (DOX) to induce cardiac dysfunction. Cumulative DOX dose was 3.6 mg/kg. Drenching was continued for 12 weeks after final DOX exposure. Despite significant increases in tissue omega-3 PUFA levels (P < .05 vs placebo), omega-3–treated sheep displayed greater signs of anthracycline cardiotoxicity than placebo animals, consisting of left ventricular dilatation and a greater decline in ejection fraction (P < .05), although myocardial fibrosis burden was similar in both groups.ConclusionsDietary intake of omega-3 PUFA fails to prevent and may indeed exacerbate DOX-induced cardiotoxicity. Clinical use of omega-3 supplementation during chemotherapy should be deferred until more information is available regarding the mechanisms of interaction between fatty acids and the myocardium during anthracycline exposure.  相似文献   
994.
BackgroundIn the failing human heart, abnormalities of Ca2+ cycling have been described, but there is scant knowledge about Ca2+ handling in the skeletal muscle of humans with heart failure (HF). We tested the hypothesis that in humans with HF, Ca2+ cycling proteins in skeletal muscle are abnormal.Methods and ResultsTen advanced HF patients (50.4 ± 3.7 years), and 9 age-matched controls underwent vastus lateralis biopsy. Western blot analysis showed that sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA)2a, which is responsible for Ca2+ sequestration into the sarcoplasmic reticulum(SR), was lower in HF versus controls (4.8 ± 0.5 vs 7.5 ± 0.8 AU, P = .01). Although phospholamban (PLN), which inhibits SERCA2a, was not different in HF versus controls, phosphorylation (SER16 site) of PLN, which relieves this inhibition, was reduced (0.8 ± 0.1 vs 3.9 ± 0.9 AU, P = .004). Dihydropyridine receptors were reduced in HF, (2.1 ± 0.4 vs 3.6 ± 0.5 AU, P = .04). We tested the hypothesis that these abnormalities of Ca2+ handling protein content and regulation were due to increased oxidative stress, but oxygen radical scavenger proteins were not elevated in the skeletal muscle of HF patients.ConclusionIn chronic HF, marked abnormalities of Ca2+ handling proteins are present in skeletal muscle, which mirror those in failing heart tissue. This suggests a common mechanism, such as chronic augmentation of sympathetic activity and autophosphorylation of Ca2+-calmodulin-dependent-protein kinase II.  相似文献   
995.
Rationale: Diabetic peripheral neuropathy is common and causes significant morbidity. Obstructive sleep apnea (OSA) is also common in patients with type 2 diabetes. Because OSA is associated with inflammation and oxidative stress, we hypothesized that OSA is associated with peripheral neuropathy in type 2 diabetes. Objectives: To assess the relationship between OSA and peripheral neuropathy in patients with type 2 diabetes. Methods: A cross-sectional study of adults with type 2 diabetes recruited randomly from the diabetes clinic of two UK hospitals. Measurements and Main Results: Peripheral neuropathy was diagnosed using the Michigan Neuropathy Screening Instrument. OSA (apnea-hypopnea index ≥ 5 events/h) was assessed using home-based, multichannel respiratory monitoring. Serum nitrotyrosine was measured by ELISA, lipid peroxide by spectrophotometer, and microvascular function by laser speckle contrast imaging. Two hundred thirty-four patients (mean [SD] age, 57 [12] yr) were analyzed. OSA prevalence was 65% (median apnea-hypopnea index, 7.2; range, 0-93), 40% of which were moderate to severe. Neuropathy prevalence was higher in patients with OSA than those without (60% vs. 27%, P < 0.001). After adjustment for possible confounders, OSA remained independently associated with diabetic neuropathy (odds ratio, 2.82; 95% confidence interval, 1.44-5.52; P = 0.0034). Nitrotyrosine and lipid peroxide levels (n = 102, 74 with OSA) were higher in OSA and correlated with hypoxemia severity. Cutaneous microvascular function (n = 71, 47 with OSA) was impaired in OSA. Conclusions: We describe a novel independent association between diabetic peripheral neuropathy and OSA. We identified increased nitrosative/oxidative stress and impaired microvascular regulation as potential mechanisms. Prospective and interventional studies are needed to assess the impact of OSA and its treatment on peripheral neuropathy development and progression in patients with type 2 diabetes.  相似文献   
996.
997.
998.
Swollen eyelids are commonly ascribed to allergic conjunctivitis, contact dermatitis, eczema, angioedema, or acute sinusitis. The differential diagnosis extends to thyroid eye disease; blepharitis; Sj?gren's syndrome; Churg-Strauss vasculitis; Wegener's granulomatosis; Gleich syndrome; orbital and ocular lymphoid hyperplasia or adnexal lymphoma; idiopathic orbital inflammatory disease/idiopathic sclerosing orbital inflammation; rarely, orbital parasitosis; and IgG4-related diseases. The likely diagnosis proceeds from the more to the less common in patients without a history of allergy or infection. Both ocular lymphoid hyperplasia and ocular adnexal lymphoma must be considered in the differential diagnosis of persistent disease, and neither of these entities can be recognized or differentiated from one another clinically or radiologically. Early diagnosis is essential because therapy may consist of frequent follow-up and/or active intervention. Outcomes in patients treated early and appropriately are often favorable.  相似文献   
999.
Men who have sex with men (MSM) are typically studied as though they were a homogeneous population. This has resulted in a lack of knowledge about the sexual health and behavior of bisexual men as distinct from gay men. In this study, patterns of sexual behavior and rates of HIV testing were compared between 854 gay-identifying and 164 bisexual-identifying men who participated in an Australian nationwide online survey. Approximately half of both groups engaged in unprotected anal intercourse (UAI) at their most recent sexual encounter, but bisexual-identifying men were more likely to have had sex with a partner who was either serodiscordant or with whom their seroconcordance was unknown. Despite these patterns, only 62% of bisexual-identifying men had ever been tested for HIV compared to 84% of gay-identifying men. Multivariate logistic regression focused on rates of UAI and HIV testing among bisexual-identifying men. Patterns were similar across all age groups and educational backgrounds. However, bisexual-identifying men were less likely to engage in UAI with a casual partner and were more likely to have been tested for HIV if they had multiple partners or had disclosed their sexual orientation to their social networks. In all, these data reveal important differences between gay- and bisexual-identifying men, particularly with regard to HIV testing, and highlight a need for HIV prevention strategies to focus more strategically on finding ways of promoting safer sex and HIV testing among all MSM.  相似文献   
1000.
The earliest hypothesis of the pathogenesis of HE implicated ammonia, although effects of appreciable concentrations of this neurotoxin did not resemble HE. Altered eurotransmission in the brain was suggested by similarities between increased GABA-mediated inhibitory neurotransmission and HE, specifically decreased consciousness and impaired motor function. Evidence of increased GABAergic tone in models of HE has accumulated; potential mechanisms include increased synaptic availability of GABA and accumulation of natural benzodiazepine receptor ligands with agonist properties. Pathophysiological concentrations of ammonia associated with HE, have the potential of enhancing GABAergic tone by mechanisms that involve its interactions with the GABAa receptor complex.  相似文献   
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