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81.
82.
Many HIV-positive people who inject drugs (PWID) globally are not receiving HIV care. This represents a major challenge among key populations to end the global HIV epidemic. This qualitative study explored the process and associated barriers of linking HIV-positive PWID who are in addiction treatment to HIV care in St. Petersburg, Russia. We conducted three focus groups and seven semi-structured interviews with participants in the LINC (“Linking Infectious and Narcology Care”) project at addiction and HIV hospitals in St. Petersburg. The sample consisted of 25 HIV-infected patients with opioid dependence and seven health-care providers, including addiction and infectious disease physicians and case managers. A variety of intertwining factors influence effective engagement of PWID with HIV treatment. Stigma, problematic patient–provider relationships, and fragmented health care were the main challenges for HIV care initiation by PWID, which were further exacerbated by injection drug use. Effective linkage of PWID to HIV care requires acknowledging and addressing stigma’s role and different perspectives of patients and providers.  相似文献   
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84.
Apart from their existence as medical curiosities, anatomic variants also double as diagnostic dilemmas. In the heart, more than in any other location in the body, misinterpretation of normal anatomic variants as pathologic entities can have a profound impact on treatment decisions and clinical consequences. Echocardiography is an easily accessible tool these days and is used routinely in most cardiac evaluations. Thus it becomes imperative for the echocardiographer to be cognizant of normal anatomic variants. Furthermore, echocardiographic findings should always be evaluated in their proper clinical context and diagnoses should never be entertained in a clinical vacuum. The literature is replete with numerous case reports and vignettes on these fascinating structures but is lacking in a formal review of normal anatomic variants. In this article, we have attempted a systemic review of normal variants, their embryologic origins, echocardiographic characteristics, and common pitfalls encountered in their evaluation.  相似文献   
85.
Venous thromboembolism (VTE) has long been considered a disease that affects predominantly white populations, a misconception resulting from a paucity of epidemiological data from non-Western countries, and the low incidence of hereditary thrombophilia in those of non-Caucasian background. Over the last decade, interest has grown in this area with the emergence of evidence that VTE is as prevalent, if not more so, in the black population and is also common in Asian groups. Much is still to be learned, as our current knowledge of hereditary thrombophilia and acquired risk factors do not fully explain the risk of VTE in non-Caucasian groups. This review summarises the current understanding of ethnic variation in VTE and highlights the need for further research in this area.  相似文献   
86.
Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers may have anti-inflammatory actions, an effect that could explain some of their beneficial effects on cardiovascular events in clinical trials. Coronary artery bypass grafting (CABG) is associated with a systemic inflammatory response and provides a convenient model to examine the effects of such agents. Genetic polymorphisms may be important in influencing the expression of cytokines, such as interleukin-6 (IL-6). We randomized men awaiting CABG to treatment with enalapril, losartan, or control for 2 months before surgery. Systemic IL-6, IL-8, IL-10, and IL-1 receptor agonists were measured before and after surgery, and genotypes for the -174 G/C and -572 G/C IL-6 gene polymorphisms were determined. Total release of the IL-1 receptor agonist was decreased 29% by enalapril and 31% by losartan (adjusted p = 0.041). IL-6 was decreased 17% by enalapril and 20% by losartan. Subjects possessing the -174 GG genotype produced 20% more IL-6 (adjusted p = 0.029). In these high producers of IL-6, release of IL-6 was decreased 51% by enalapril (adjusted p = 0.001) and 32% by losartan (adjusted p = 0.068). Release of IL-10 was nonsignificantly decreased 26% by enalapril and 21% by losartan, whereas IL-8 was not detected. In conclusion, enalapril and losartan significantly decreased release of the IL-1 receptor agonist after CABG. Enalapril produced a highly significant decrease of 51% in the release of IL-6 in patients identified as high producers of IL-6 by the -174 G/C polymorphism, whereas losartan has a similar but less marked effect. The production of IL-6 in this setting is influenced by the -174 G/C polymorphism.  相似文献   
87.
We prospectively and blindly assessed the diagnostic and prognostic impact of implementation of the European Society of Cardiology/American College of Cardiology recommendations for redefinition of myocardial infarction (MI) in an unselected cohort of patients with suspected cardiac chest pain, with particular attention to prespecified clinical groups. All patients admitted to our institute with suspected cardiac chest pain were enrolled. Physicians provided usual care using serial electrocardiograms/creatine kinase (CK)/aspartate transaminase according to World Health Organization (WHO) criteria for MI, while blinded to additional measurements of cardiac troponin T (cTnT) and CK-MB mass. After discharge, diagnoses based on WHO and new criteria were compared, and major adverse cardiac events monitored for 6 months. Implementation of the new recommendations classified an additional 26.1% of patients as having MI compared with WHO criteria, and produced an overall diagnostic alteration in 11.5%. Two thirds of the additional patients with MI were previously diagnosed with unstable angina, whereas one third had "other cardiac" or "noncardiac" diagnoses. A similar MI cohort to the cTnT diagnosis was identified using a CK-MB mass discriminator value of 5 microg/L, but not 10 microg/L. The 6-month prognosis was similar in patients diagnosed with MI by new (cTnT) and WHO criteria, with the new criteria thus identifying a further high-risk cohort in the WHO negative group. In our cohort, the new Joint European Society of Cardiology/American College of Cardiology recommendations identify one fourth more patients as having MI. The 6-month prognosis of those patients reclassified as having MI was similar to those diagnosed with MI by both criteria.  相似文献   
88.
OBJECTIVES: To determine whether a change in practice to introduce a multidisciplinary fall-prevention program can reduce falls and injury in nonacute patients in a rehabilitation hospital. DESIGN: A quasi-experimental study. SETTING: Three geriatric wards with a similar design, equipment, staffing levels, and skill mix. PARTICIPANTS: Eight hundred twenty-five consecutive patients. INTERVENTION: The patients' fall-risk status was assessed using the Downton Score. Current practice was maintained on the two control wards (n=550). On the experimental ward (n=275), a fall-prevention program was introduced. A multidisciplinary team met weekly specifically to discuss patients' fall risk and formulate a targeted plan. Patients at risk were identified using wristbands; risk factors were corrected or environmental changes made to enhance safety. MEASUREMENTS: Primary outcomes were number of fallers, recurrent fallers, total falls, patients sustaining injury, and falls per occupied bed days. Secondary outcomes were place of discharge and mortality. RESULTS: Patients were matched for age and risk status. Control wards had proportionally more fallers (20.2% vs 14.2%: P=.033), patients sustaining injury (8.2% vs 4%: P=.025), and total number of falls (170 vs 72: P=.045). These results did not remain significant after controlling for differing length of stay. There was no reduction in recurrent fallers (6.4% vs 4.7%: P=.43) and no effect on place of discharge (home discharges; 57.5% vs 60.7%: P=.41) or mortality (15.3% vs 13.8%: P=.60). CONCLUSION: This study shows that falls might be reduced in a multidisciplinary fall-prevention program, but the results are not definitive because of the borderline significance achieved and the variable length of stay. More research on fall prevention in hospital is required, particularly as to what interventions, if any, are effective at reducing falls in this group of patients.  相似文献   
89.
We have determined the effect of prostacyclin (PGI2) on segmental vascular resistance in rabbit lungs. Lungs of 26 rabbits were isolated and perfused with blood; 16 adult, greater than 6 months old, five juvenile, 6-8 week old and five neonatal, 2-3-week old. Six of the adult lungs were pretreated with indomethacin to block cyclooxygenase, prior to infusion of PGI2. In all lungs, flow was adjusted initially to keep pulmonary artery pressure approximately 20 cmH2O, left atrial and airway pressures being 8 and 6 cmH2O, respectively (zone 3), and then kept constant. We measured pulmonary artery pressure continuously and in the 10 untreated adult lungs, in which a vasoconstrictor response to PGI2 was obtained, we also measured pressures in 20-50 microns diameter subpleural arterioles and venules by the micropipette-servonulling method. We found that in juvenile and neonatal rabbit lungs, PGI2 did not change total vascular resistance significantly but in untreated adult lungs, it caused a significant increase in total vascular resistance only after a dose of 10 micrograms/kg. This age-related difference in vasoconstrictor response to PGI2 was not related to baseline total vascular resistance in the three groups of lungs. In adult lungs, vasoconstriction occurred mainly in arteries with a small effect in veins. Circulating levels of thromboxane B2, leukotriene C4, and 6-keto-PGF1 alpha increased following PGI2 infusion in adult lungs, whereas in neonatal lungs, only 6-keto-PGF1 alpha increased significantly. Indomethacin pretreatment completely abolished the vasoconstrictor response to PGI2. We conclude that PGI2-induced vasoconstriction is age and dose dependent in isolated rabbit lungs and that a cyclooxygenase product, such as thromboxane A2, may play a role in mediating the vasoconstriction.  相似文献   
90.
BB10010/MIP-1 alpha reduces the number of proliferating cells in the small intestine, strongly suggesting a radioprotective potential in this organ. This study was designed to optimize BB10010 administration for maximal radioprotection. In single administration protocols 1 or 4 mg/kg of BB10010 was injected into mice 2, 4 or 10 hr before death. In double administration protocols an initial dose of either 0.4 or 200 g/kg, and a second dose (2.5 hr apart) of 200 g/kg 4 hr before death were administered. The number of vincristine-arrested metaphases were counted on individually microdissected crypts from the midpoint of the small intestine. When compared to the smaller doses of BB 10010 used in our previous studies, the higher doses used in these experiments did not result in any further reduction in the number of proliferating cells under any of the protocols assessed. Furthermore, some values were found to be above not only those observed with the smaller doses, but also above untreated controls. It is concluded that a single dose of 200 g/kg of BB10010 offers the most consistent reduction of mitotic cells, and is, therefore, considered optimal for assessment of radioprotection.  相似文献   
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