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The results discussed in this report are part of a larger study conducted among the students of the University of Botswana regarding their knowledge, attitudes, and behaviors related to HIV/AIDS. The study triangulated survey methods and focus group discussions. Five main areas were investigated: knowledge and personal experiences of HIV/AIDS, sexual behavior and practices, perceptions about risky sexual behavior on campus, and factors that influence the spread of HIV. This article reports high levels of risky behaviors such as alcohol and drug abuse; unprotected sex; frequent change of sexual partners; sex for financial gain, for prestige, for good grades, to relieve stress, and because of peer pressure; and casual sex as part of socializing. 相似文献
995.
Use of Microsphere Technology for Targeted Delivery of Rifampin to Mycobacterium tuberculosis-Infected Macrophages 总被引:1,自引:0,他引:1
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Esther L. W. Barrow Gary A. Winchester Jay K. Staas Debra C. Quenelle William W. Barrow 《Antimicrobial agents and chemotherapy》1998,42(10):2682-2689
Microsphere technology was used to develop formulations of rifampin for targeted delivery to host macrophages. These formulations were prepared by using biocompatible polymeric excipients of lactide and glycolide copolymers. Release characteristics were examined in vitro and also in two monocytic cell lines, the murine J774 and the human Mono Mac 6 cell lines. Bioassay assessment of cell culture supernatants from monocyte cell lines showed release of bioactive rifampin during a 7-day experimental period. Treatment of Mycobacterium tuberculosis H37Rv-infected monocyte cell lines with rifampin-loaded microspheres resulted in a significant decrease in numbers of CFU at 7 days following initial infection, even though only 8% of the microsphere-loaded rifampin was released. The levels of rifampin released from microsphere formulations within monocytes were more effective at reducing M. tuberculosis intracellular growth than equivalent doses of rifampin given as a free drug. These results demonstrate that rifampin-loaded microspheres can be formulated for effective sustained and targeted delivery to host macrophages. 相似文献
996.
Chang E Hancock K Hickman L Glasson J Davidson P 《International journal of nursing studies》2007,44(7):1079-1092
BACKGROUND: There is a lack of research investigating models of nursing care for older hospitalised patients that address the nursing needs of this group. OBJECTIVES: The objective of this study is to evaluate the efficacy of models of care for acutely older patients tailored to two contexts: an aged care specific ward and a medical ward. DESIGN: This is a repeated measures design. Efficacy of the models was evaluated in terms of: patient and nurses' satisfaction with care provided; increased activities of daily living; reduced unplanned hospital readmissions; and medication knowledge. SETTINGS: An aged care specific ward and a medical ward in two Sydney teaching hospitals. PARTICIPANTS: There were two groups of patients aged 65 years or older who were admitted to hospital for an acute illness: those admitted prior to model implementation (n=232) and those admitted during model implementation (n=116). Patients with moderate or severe dementia were excluded. The two groups of nurses were the pre-model group (n=90) who were working on the medical and aged care wards for the study prior to model implementation, and the post-model group (n=22), who were the nurses working on the wards during model implementation. METHODS: Action research was used to develop the models of care in two wards: one for an aged care specific ward and another for a general medical ward where older patients were admitted. The models developed were based on empirical data gathered in an earlier phase of this study. RESULTS: The models were successful in both wards in terms of increasing satisfaction levels in patients and nurses (p<0.001), increasing functional independence as measured by activities of daily living (p<0.01), and increasing medication knowledge (p<0.001). CONCLUSIONS: Findings indicate that models of care developed by nurses using an evidence-based action research strategy can enhance both satisfaction and health outcomes in older patients. 相似文献
997.
The locus coeruleus (LC) is involved in several neural pathways responsible for some somatic and emotional processes, such as pain and depression; its activity is regulated by several receptors, such as opioid, alpha(2)-adrenergic, and 5-hydroxytryptamine (5-HT)(1A) receptors. The present study investigates the in vivo effects of venlafaxine, an antidepressant with analgesic properties, on locus coeruleus neurons, and its modulation by opioid, alpha(2)-adrenergic, and 5-HT(1A) receptors. The results show that acute administration of venlafaxine produced a dose-dependent, complete inhibition of LC activity. This inhibitory effect was not reversed by the opioid receptor antagonist naloxone, but subsequent administration of idazoxan, an alpha(2)-adrenoceptor antagonist, did reverse it. The preadministration of the 5-HT(1A) receptor agonist 8-hydroxy-2-dipropylaminotetralin (8-OH-DPAT) (1 and 40 microg/kg) significantly enhanced the venlafaxine inhibitory effect, decreasing the ED(50) by 56 and 44%, respectively. A 14-day treatment with venlafaxine (40 mg/kg/day) induced a suppression of the firing activity of LC neurons. In these treated animals, venlafaxine produced an inhibitory effect similar to that in nontreated animals. This inhibitory effect was not reversed by naloxone, but it was reversed by idazoxan. In addition, the preadministration of 8-OH-DPAT (40 microg/kg) significantly enhanced the venlafaxine effect, decreasing the ED(50) by 60%. These results suggest that the effect of venlafaxine on LC neurons is modulated by alpha(2)-adrenergic and 5-HT(1A) receptors, and not by opioid receptors. These data could contribute to the further understanding of the antidepressant and analgesic mechanism of action of venlafaxine. 相似文献
998.
Compromised lymphocytes infiltrate hepatocellular carcinoma: the role of T-regulatory cells 总被引:26,自引:0,他引:26
Unitt E Rushbrook SM Marshall A Davies S Gibbs P Morris LS Coleman N Alexander GJ 《Hepatology (Baltimore, Md.)》2005,41(4):722-730
Hepatocellular carcinoma (HCC) has a poor prognosis with limited therapeutic options. We propose that local immune responses in patients with HCC are held in check by tumor-infiltrating CD4(+)CD25(+) T-regulatory lymphocytes (T(reg) cells), which suppress the activity and proliferation of effector CD4(+) and CD8(+) T cells. The phenotype and cell cycle status of tumor-infiltrating lymphocytes (TILs) in HCC were analyzed via immunohistochemistry of sections from patients undergoing surgery for HCC and via flow cytometry of peripheral blood mononuclear cells and TILs isolated from patients with HCC. Circulating and tumor-infiltrating T-cell function and activation status were assessed via proliferation and flow cytometry. More than 96% of TILs were quiescent as measured via Mcm-2 or Ki-67 expression, while less than 10% of CD8(+) T cells expressed perforin or granzyme B. CD4(+)CD25(+) T(reg) cells comprised 8.7% (1.4-13.8) of TILs and always exceeded the proportion in distant nontumor tissue (2.4% [1.5-5.6]; P = .014). T(reg) cells isolated from HCC suppressed proliferation of autologous circulating CD4(+)CD25(-) cells and perforin expression and proliferation of autologous CD8(+) T cells. The proportion of circulating T(reg) cells in patients with HCC was similar in healthy controls (7.2% [1.2-23.3] and 9.2% [1.6-30.2], respectively), but the proportion of circulating T(reg) cells that were also transforming growth factor beta1(+) was elevated in HCC compared with controls (55.5% [8.2-73.9] and 2.0% [0-4.9], respectively; P = .003). In conclusion, TILs are compromised and contain a subpopulation of suppressive CD4(+)CD25(+)Foxp3(+) T(reg) cells. Functional deletion of tumor-infiltrating T(reg) cells could enhance tumor-specific immunotherapy. 相似文献
999.
BACKGROUND: Lung transplants have been performed worldwide since the early 1980s. While numerous studies have been published on somatic aspects after lung transplantation, there is considerably less information available on psychosocial aspects and on the correlation between the physical and the psychosocial state of health after transplantation. METHODS: Between 1992 and 2002, 125 patients underwent lung transplantation at University Hospital Zurich. To be included into the study, patients had to have received a lung transplant > 12 months previously and to have good knowledge of the German or Italian languages. With the aid of standardized questionnaires, psychosocial variables such as levels of anxiety and depression, self-esteem, and social support were determined. In addition, self-assessments of physical and psychological health were obtained. The medical data included information on FEV1, complications such as pulmonary infections, acute or chronic allograft rejection, and assessment of the patient's physical and psychological health by the treating doctors. RESULTS: The overall degree of anxiety and depression of the lung transplant recipients was comparable to standard samples of an average population. However, male lung transplant recipients were significantly more depressed than female recipients. Self-esteem was higher than in clinical comparison samples. Preceding pulmonary complications had long-lasting effects on the level of anxiety, whereas nonpulmonary complications did not have such an effect. CONCLUSIONS: Overall, the psychological well-being of patients after lung transplantation is similar to the normal population. Subgroups of patients with increased psychological distress have been identified. 相似文献