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81.
The introduction of highly active antiretroviral therapy (HAART) has resulted in marked reductions in mortality and acquired immunodeficiency syndrome (AIDS) incidence across all risk groups; however, the proportionate decrease among injecting drug users (IDUs) has been less impressive. Much of the disparity in benefit to IDUs has been a consequence of decreased access to and receipt of potent antiretroviral combinations. Strategies to increase access to and utilization of HAART have included entry into drug treatment and abstinence. Unfortunately, as few as 15%–20% of active drug users in the United States, and in many other countries, are in drug treatment at any one time. We report a pilot project among out-of-drug treatment IDUs infected with human immunodeficiency virus (HIV); HIV therapy was successfully provided to active heroin injectors using the Community Health Care Van (CHCV) at sites of needle exchange. Subjects were willing to initiate, but were not receiving, recommended HIV therapy and were not interested in formal drug treatment. Antiretroviral therapy regimens were selected and linked to heroin injection timing. Weekly visits were scheduled by CHCV staff to assess adverse side effects and encourage adherence. Of the 13 participants, the mean baseline HIV-1 RNA level and CD4 lymphocyte count were 162,369 (log 5.21) copies per milliliter and 265 cells per milliliter, respectively. By 6 months, the proportion whose HIV-1 RNA was below the limits of detection (<400 copies/mL) was 85% (N=11); 77% (N=10) had nondetectable levels by 9 months. By 12 months, 54% (N=7) had a persistently nondetectable viral load, and the net increase in CD4 lymphocyte count was 150 cells per milliliter. As an additional and unintended benefit of this pilot project, 9 (69%) subjects chose to enter drug treatment after achieving a nondetectable viral load. Entry into drug treatment was associated with durability of viral suppression. This small pilot study suggests that health services based on needle exchange may enhance access to HAART among out-of-treatment HIV-infected IDUs. In addition, it demonstrates that this population can benefit from this therapy with the support of a nontraditional, community-based health intervention.  相似文献   
82.
The spatial and temporal pattern of expression of the protein products of immediate early genes (IEGs) c-fos, fos B, and egr-1 were mapped in medial preoptic area (MPOA) and ventral bed nucleus of stria terminalis (VBST) during maternal behavior in rats. Immunocytochemical analysis indicated significant increases in the number of cells expressing c-Fos after 2 h of pup exposure, while Fos B levels showed a delayed response, reaching maximal levels after 6 h.  相似文献   
83.
OBJECTIVE Little information is available regarding the regulation of serum acid-labile subunit (ALS) in human disease. We have studied alterations in serum ALS of the insulin-like growth factor (IGF) ternary complex in children with untreated insulin-dependent diabetes mellitus (IDDM) and subjects with severe burns before and after insulin therapy. In addition, we have investigated the effect of insulin plus GH on serum ALS in burn patients. DESIGN Serum samples were obtained from children with newly diagnosed and untreated IDDM before the initiation of insulin therapy and 1 month thereafter. Serum samples were also obtained from adult patients with severe burns who were on a continuous infusion of a carbohydrate-rich enteral diet via nasogastric and duodenal catheters under basal conditions, after a 1-week period of continuous insulin infusion, and after an additional week of insulin plus recombinant GH. PATIENTS Twenty children and adolescents with untreated IDDM, aged 1.2–16 years, and 6 young adult patients with severe burns aged 17–28 years were studied longitudinally. Control sera were obtained from age, sex and pubertal status matched subjects (for children with IDDM) and from fed healthy adults. MEASUREMENTS Serum insulin, GH, cortisol and IGF-I were measured by radioimmunoassay, and serum ALS levels were assessed by Western immunoblot before and after treatment periods. RESULTS Serum ALS levels were lower in untreated children with IDDM (69 ± 6% of control children). Insulin therapy significantly increased serum ALS (79 ± 5%, P<0.05) in these children. Patients with severe burns also had lower serum ALS levels (79 ± 10% of control adults). After one week of insulin therapy serum ALS levels increased to 90 ± 15% of control values (P<0.05). Addition of GH to insulin therapy for another week did not significantly further increase serum ALS levels (95 ± 27%). Serum IGF-I concentrations increased nearly 2.5-fold in diabetic subjects and fourfold in burn subjects at the end of the study periods. There were no proteolytic fragments of ALS in the sera studied. The deglycosylation pattern of ALS did not differ between diabetic and control sera. CONCLUSION Serum ALS levels were diminished in children with untreated IDDM and were partially restored after the initiation of insulin therapy. Serum ALS levels were also diminished in patients with severe burn injury and restored by insulin treatment. Addition of GH to insulin therapy did not significantly increase serum ALS levels over levels obtained during insulin therapy alone. These decreases in serum ALS were smaller than the decrease in serum IGF-I concentrations in both conditions, suggesting that IGF-I is the limiting factor for the ternary complex formation in the catabolic states. Insulin may regulate circulating ALS levels in catabolic states and helps to restore the IGF system.  相似文献   
84.
Objective: To explore patterns in the practice of nursing and patient outcomes.
Design: Qualitative field research.
Population, Sample, Setting: Populations were critical care nurses and critically ill adult patients in the 10-bed medical critical care unit of a 900-bed teaching hospital. A convenience-purposive sample of 27 nurses and 31 patients was studied in 1985.
Methods: Six months of participant observation, unstructured interviews, and the constant comparison method of grounded theory.
Findings: Markedly different patterns were found in expert and nonexpert practice. The substantive theory of conversion helped explain how the majority of nonexpert nurses advanced their practice. The metaphor of catalyzed conversion captures how a unit-based expert nurse serves as a catalyst to advance the practice of nonexperts. Presence, defined as the way of being within a given clinical context, differentiated nurses.
Conclusions: (a) Expert and nonexpert practices are substantively different, (b) Expert and nonexpert practice results in different patient outcomes, (c) Conversion helps explain changes in nonexpert practice.
Clinical Implications: A unit-based expert nurse can increase patient-focused care.  相似文献   
85.
Summary These studies were designed to determine the role of the central nervous system, the sympathetic nervous system, the adrenal glands and the renal sympathetic nerves in yohimbine-induced renin release in conscious rats. Yohimbine (0.3–10 mg/kg, s.c.) caused time- and dose-related increases in plasma renin activity (PRA) and concentration (PRC) which were accompanied by time- and dose-related elevations of plasma norepinephrine (NE) and epinephrine (Epi) concentrations. Significant positive correlations were found between the increases in PRA and the increases in plasma NE and Epi concentrations caused by yohimbine, and propranolol (1.5 mg/kg, s.c.) blocked 90% of yohimbine (3 mg/kg, s.c.)-induced renin release. Over the entire spectrum of doses of yohimbine, the increases in PRA and plasma NE and Epi concentrations were positively correlated with the decreases in mean arterial pressure (MAP), but the -intercept was positive in every case and the 1 mg/ kg dose of yohimbine consistently increased PRA independent of any change in MAP. Complete renal denervation, as evidenced by a greater than 90% reduction in renal NE content, did not alter the increase in PRA caused by yohimbine (3 mg/kg, s.c.). An increase in circulating plasma catecholamine concentrations appeared to mediate yohimbine-induced renin release since propranolol prevented the rise in PRA caused by yohimbine in renal denervated rats. Prior adrenalectomy (Adx) also failed to prevent the rise in PRA produced by yohimbine (3 mg/kg, s.c.), but a combination of Adx and renal denervation caused a significant impairment of yohimbine-induced renin release. However, neither Adx alone nor the combination of Adx and renal denervation affected the increase in plasma NE concentration caused by yohimbine. Complete transection of the spinal cord at C8 caused a drastic reduction in plasma catecholamine concentrations but did not change basal PRC. Yohimbine (3 mg/kg, s.c.) did not increase PRC or plasma catecholamine concentrations after spinal transection. Based on these results, we conclude that 1) the stimulation of renin release by yohimbine is a secondary neurohormonal consequence of the generalized increase in sympathetic activity caused by yohimbine, 2) the sympathoadrenal activation produced by yohimbine results from an action in the brain which is amplified by the simultaneous blockade of prejunctional 2-adrenoceptors and 3) vasodepressor effects of the larger doses yohimbine cause a baroreflexly-mediated increase in sympathetic activity which interacts in a positive fashion with the central and peripheral sympathoexcitatory effects of yohimbine. Send offprint requests to T. K. Keeton  相似文献   
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This study aims to investigate MMP2 and MT1-MMP protein as well as VEGF-C and VEGF-D mRNA expression in tumor cells and distant organs considered to be targets for metastasis in a tumor spontaneous metastasis model previously described. Cultured tumor cells, able to express pro-MMP2, MMP2, pro-MMP9, and MT1-MMP, develop tumor growth and metastasis, mainly in the liver and spleen, when they are injected in the mammary pad gland of Wistar rats. Immunohistochemical studies of tumor masses showed small groups of tumor cells staining for MT1-MMP but not for MMP2. In the liver, tumor metastatic foci and a stromal positive staining for both MMP2 and MT1-MMP were shown. The spleen and lymph nodes, with only scattered metastatic cells, did not show MMPs immunostaining. Using RT-PCR, a significantly higher VEGF-C and VEGF-D gene expression was shown in the liver of tumor-bearing rats respect to normal rats, whereas spleen and lymph nodes did not show significant differences in mRNA VEGF-C/D levels. Taken together, our results suggest that the stroma microenvironment of target organs for metastasis has the ability to produce MMPs and VEGFs that facilitate the anchorage of tumor cells and promote tumor cell growth and angiogenesis.  相似文献   
90.
Vitamin E affects cell death in adult rat dentate gyrus   总被引:1,自引:0,他引:1  
We have previously reported the presence of dying cells in the granule cell layer (GCL) of adult rat dentate gyrus (DG), where neurogenesis occurs. In particular, we found that cell death in the GCL increased in vitamin E deficiency and decreased in vitamin E supplementation. These findings were regarded as related to changes in neurogenesis rate, which in turn was influenced by vitamin E availability; a neuroprotective effect of vitamin E on cell death was also proposed. In order to verify this latter hypothesis, we have studied cell death in all layers of DG in vitamin E-deficient and vitamin E-supplemented rats and in control rats at different ages, using TUNEL and nick translation techniques. The phenotype of TUNEL-positive cells was characterized and the existence of dying BrdU-positive cells was investigated. Dying cells with neuronal phenotype were observed throughout the DG in all experimental groups. The number of TUNEL-positive cells decreased from juvenile to adult age. A higher number of TUNEL-positive cells in vitamin E-deficient rats and a lower number in vitamin E-supplemented rats, with respect to age-matched controls, were found; moreover, in these groups, TUNEL-positive cells had a different percentage distribution in the different layers of the DG. Our results confirm the occurrence of cell death in DG, demonstrate that cell death affects neuronal cells and support the hypothesis that the effect of vitamin E on cell death is not related to neurogenesis.  相似文献   
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