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This study piloted a brief individual motivational intervention targeting multiple health risk behaviors in HIV-positive youth aged 16-25. Interviews about sexual behavior and substance use and viral load testing were obtained from 51 HIV-positive youth at baseline and post intervention. Youth were randomized to receive a four-session motivational enhancement intervention (N = 25) or to a wait-list control (N = 26). Of the eligible youth approached, 88% agreed to participate, and 80% percent of participants completed at least three of four sessions. The treatment group showed significantly greater reductions in unprotected sex acts and in viral load compared with controls. Although change scores for substance use were not significantly different between the two groups, paired t tests demonstrated that reductions in alcohol use and marijuana use were significant for the treatment group at the trend level. There were no significant differences in substance use from baseline to posttest for the control group. Findings demonstrate the potential of a brief motivational enhancement intervention to improve health risk behaviors in HIV-positive youth. Larger randomized clinical trials are warranted. Resources required for retention should not be underestimated.  相似文献   
94.
MRI evaluations of intramyocardial hemorrhage in acute infarction have relied on T(2) and T(2)(*) shortening only. We propose a more comprehensive evaluation of hemorrhagic infarction based on the concept that fluctuations in T(2) and T(1) relaxation in acute reperfused infarction will reflect transient edema and hemoglobin oxidative denaturation to uncompartmentalized methemoglobin. Anteroapical infarction was created via percutaneous balloon in young swine (22-25 kg, N = 12). T(2), T(1), diastolic wall thickness (DWT), and the Gd-DTPA partition coefficient (lambda) were measured on days 0, 2, and 7. DWT was elevated at 1 hr postreperfusion (128% +/- 53%, P = 0.0001), and alleviated on days 2 and 7 (48% +/- 10%, P = 0.008; 53% +/- 24%, P = 0.003). T(2) and T(1) elevations were coincident with early edema (DeltaT(2) = 55% +/- 24%, P < 0.0001; DeltaT(1) = 27% +/- 18%, P < 0.04). T(2) and T(1) were nearly normal on day 2 (DeltaT(2) = 8% +/- 8%, P = 0.27; DeltaT(1) = 0% +/- 1%, P = 0.65). On day 7, T(2) increased while T(1) decreased (DeltaT(2) = 27% +/- 16%, P = 0.005; DeltaT(1) = -14% +/- 10%, P = 0.02). Lambda was elevated by >150% at all time points (P < or = 0.002). Histology verified hemorrhagic injury. T(1) and T(2) fluctuations are consistent with transient edema, as well as hemoglobin oxidative denaturation to decompartmentalized methemoglobin. This methodological development may broaden our understanding of hemorrhagic microvascular injury and improve its detection in clinical populations.  相似文献   
95.
Multiple molecular forms of cyclic nucleotide phosphodiesterase have been characterized in various tissues and cells according to their substrate specificity, intracellular location, and calmodulin dependence. The purpose of this study was to evaluate the possible involvement of different molecular forms of phosphodiesterase in regulating the respiratory burst and lysosomal enzyme release responses of human neutrophils. Treatment with the selective cyclic AMP-specific, cyclic GMP-insensitive phosphodiesterase inhibitors Ro 20-1724 or rolipram, or the nonselective phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), resulted in inhibition of respiratory burst stimulated by the chemoattractants formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) (IC50 values: 0.71-17 microM) and complement fragment C5a (IC50 values: 61-93 microM), but did not inhibit phagocytosis-stimulated respiratory burst (less than 10% inhibition at 100 microM). Selective inhibitors of calmodulin-dependent phosphodiesterase (ICI 74,917), calmodulin-insensitive, cyclic GMP-specific phosphodiesterase (M & B 22,948), cyclic GMP-stimulated phosphodiesterase (AR-L 57), or cyclic AMP-specific, cyclic GMP-inhibited phosphodiesterase (amrinone and cilostamide) exhibited little or no inhibitory effect on FMLP- or phagocytosis-stimulated respiratory burst (0-42% inhibition at 100 microM). Regulation of neutrophil activation by phosphodiesterase was also response specific, as Ro 20-1724, rolipram and IBMX were less potent inhibitors of FMLP-induced lysosomal enzyme release (0-14% inhibition at 100 microM). Analysis of human neutrophil preparations confirmed the existence of a cyclic AMP-specific, cyclic GMP-insensitive phosphodiesterase, which was associated with the particulate fraction of the cell. These results demonstrate a role for the cyclic AMP-specific, cyclic GMP-insensitive phosphodiesterase in the regulation of human neutrophil functions, which appears to be both stimulus specific and response specific.  相似文献   
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97.
We have reviewed the clinical presentation of 100 consecutive culture positive cases of brucellosis which came under our care during the last two years. Of these, six had atypical presentations and but for the routine practice of sending blood for brucella culture, the diagnosis would have been missed. The unusual presentations included a 19 year old boy presenting as an acute abdomen ending in laparotomy, a 52 year old man presenting with a psoas abscess, a 29 year old woman presenting with a transient perinephric mass, a 75 year old man with an acute flare up of his osteoarthritis, a 65 year old diabetic man presenting in an insulin-resistant diabetic state and a 35 year old man presenting with a cauda equina syndrome.  相似文献   
98.
Vinylogous hydroxamic acids (3-(N-hydroxy-N-alkylamino)-2-propen-1-ones, VHA) were prepared as antiinflammatory agents. The synthesis, chemical properties, and in vitro biological activities of these relatively unexplored compounds are described. The VHAs were prepared by condensation of the appropriate N-substituted hydroxylamine with any of the three reagents: a 1,3-dicarbonyl compound (method A); a vinylogous amide (method B); or an alkynone (method C). The VHAs exist as one or more tautomers in solution with the relative proportions of each being dependent upon the structure of the VHA, solvent, and pH. VHAs undergo some of the typical reactions of hydroxamic acids as well as those of vinylogous amides. VHAs are active as inhibitors of 5-lipoxygenase and of IL-1 biosynthesis in vitro, which do not inhibit other enzymes of the arachidonic acid cascade. They have been shown by ESR studies to bring about inhibition of soybean type 1 15-lipoxygenase by reduction of the active site iron.  相似文献   
99.
Twenty-two adult patients with uncontrolled epilepsy and severe learning difficulties were included in an open study of vigabatrin. Patients were all in residential care and had experienced at least 12 seizures during the previous 12 months despite all attempts to optimize antiepileptic drug (AED) treatment. Following a 4 month baseline period, vigabatrin 500 mg twice daily was added to the current AED treatment and the dose increased according to response, up to a maximum of 4 g/day. Ten patients achieved a reduction in seizure frequency of more than 50% during this 4 month dose titration phase. Two patients had no seizures during the baseline period. For the 30 patients with seizures during the baseline period the median improvement in seizure frequency with the addition of vigabatrin was 49% (P = 0.014). The response rate was higher for patients with partial seizures than for those with generalized seizures. Ten patients continued with vigabatrin while the dose of one of their other AEDs was gradually reduced and successfully withdrawn in three patients. Adverse events were reported in 20 patients during the 64 week study period. The most frequently reported events were sedation (8 patients), aggression (4 patients), agitation (3 patients) and ataxia (3 patients). No patients were withdrawn from the study as a consequence of adverse events. Vigabatrin was therefore an effective add-on therapy in 45% of these difficult-to-treat patients and allowed reduction of other AED treatment in a small number.  相似文献   
100.
Self-expanding endovascular graft: an experimental study in dogs   总被引:2,自引:0,他引:2  
An arterial endovascular graft was constructed by wrapping an expandable nylon mesh around a framework of Gianturco self-expanding metallic stents. The devices were passed through a 12-French Teflon catheter and positioned in the normal abdominal aorta of five dogs, two of which also had a device placed in an external iliac artery. At follow-up (1-6 months), all grafts remained patent, even though slight luminal narrowing due to neointimal encasement was noted. Histologically, all grafts were covered by neointimal proliferation at the time of removal. The graft material expanded with the stents, resulting in a tight fit between the graft and the vessel wall. Side branches narrowed but remained open because of the size of the nylon mesh. No migration of the grafts equipped with a barbed lead stent was noted. Expandable nylon mesh can be used as an endovascular graft material when wrapped around a framework of self-expanding stents. The resulting device can be easily delivered via transcatheter techniques, and once placed in a vessel, the nylon acts as a support for neointimal encasement, which forms a new vascular lumen.  相似文献   
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