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This study compared the predictive value of the theory of planned behavior in university students in South Africa (N = 251) and the United States (N = 160) who completed an anonymous self-administered questionnaire. Multiple regression analyses revealed that condom use and intention were significantly predicted by positive condom attitude, subjective norm, self-efficacy, and attending university in South Africa. Significant interactions between country and predictors indicated that subjective norm predicted condom use and intention more strongly in the American sample than in the South African sample; attitude predicted intention more strongly in the American sample than in the South African sample; but self-efficacy predicted intention more strongly in the South African sample than in the American sample. The theory of planned behavior may provide a useful framework for interventions to reduce South African students' risk of HIV/and sexuality transmitted diseases. Such interventions should especially focus on building self-efficacy to use condoms.  相似文献   
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Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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Few studies have investigated mediator effects of HIV prevention interventions on adolescents in sub-Saharan Africa. Herein, we report on a secondary analysis of an intervention that increased intentions to use condoms, abstain from sexual intercourse, and seek safe male circumcision among adolescents in Botswana. In a study conducted in Botswana, 806 grade 9 students from 21 public Junior Secondary Schools were randomly assigned to either the OWN THE FUTURE: Pulling Together We Will” ( PTWW) intervention group or a health promotion control group. Both conditions consisted of 12 1-h modules, with two modules delivered during each of the six sessions on six consecutive school days. The students in both groups completed confidential computer-based surveys at several time points: pre-, immediately post-, 3, 6, and 12 months post-intervention. Mediation was assessed using the product-of-coefficients approach in a generalized estimating equations (GEE) framework. The analyses showed that condom use beliefs were significant mediators of the intervention effect on the intention to consistently use condoms over time. Also, negative socio-cultural beliefs, prevention beliefs, and HIV/STI knowledge were significant mediators of the intervention’s effects on the intention to abstain from sex. Additionally, normative beliefs, prevention beliefs, parental negotiation, and circumcision knowledge were significant mediators of the intervention’s effect on intention to seek safe male circumcision. The mediation analysis delineated a theoretical model and isolated activities that positively impact condom use, abstinence from sex, and circumcision intentions of Batswana middle school adolescents.

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To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting.  相似文献   
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When children know their HIV serostatus, they are more likely to cooperate with steps to manage their health and the risk of transmitting HIV to others. Mounting evidence indicates that caregivers often do not disclose to HIV-positive children that the children are living with HIV, but little is known about the modifiable determinants of pediatric HIV disclosure. The present study examined theory-of-planned-behavior predictors of the intention to disclose to children their HIV diagnosis. The participants were 100 caregivers of HIV-positive children in Eastern Cape Province, South Africa. Proportional-odds logistic regression analysis revealed that normative support for disclosure and caregiver-child communication predicted the intention to disclose, whereas behavioral beliefs regarding the consequences of disclosing and self-efficacy to disclose did not. The results suggest that interventions to increase pediatric HIV disclosure in South Africa should help caregivers enlist support for disclosure among important referents and improve communication with their HIV-infected children.  相似文献   
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Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries.  相似文献   
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