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1.
A cross-sectional study of female condom awareness, usage and concerns among the female undergraduates of the University of Ibadan was conducted in September 2004. The results of 850 out of the 879 female students interviewed were used for analysis (96.6%). Over 80% had knowledge of the female condom as a form of modern contraception and the majority of them learnt about it through the mass media (39.9%) and health workers (34.4%). However, only 11.3% had ever used the female condom, with most (40%) using it to prevent both unwanted pregnancy and sexually transmitted infections including HIV (STI/HIV). The sexual partners' approval was appreciable, accounting for about 42.7% among those that had experience of the female condom usage. Major concerns mentioned such as difficulty of inserting it into the vagina and lack of sexual satisfaction, were not different from those in earlier studies. The result of this study looks promising judging from a high awareness level of the female condom, even though its usage is low. The female condom may be an alternative strategy to combat unsafe sexual practises and its sequelae in a country like Nigeria that is male dominated.  相似文献   
2.
Regulatory agencies traditionally use doses associated with ambient concentrations of contaminants in environmental media to estimate lifetime excess cancer risks. This approach is, however, limited by the errors inherent in making several default assumptions such as daily water and food intakes and organ absorption factors. A methodology was developed in this study to estimate daily human doses of chlordane and heptachlor from measured metabolites in adipose tissue. Human biomonitoring data, pharmacodynamic and pharmacokinetic parameters in humans and animals, and selected dose-response data from animal carcinogenicity studies were utilized in this procedure for cancer risk assessment in man. Conversion factors, based on body surface area, were used for animal-to-man extrapolation. Conservative estimates from the Global 82 linearized multistage mathematical model (95% upper confidence limit) associate a 1 x 10(-5) risk probability level to chlordane and heptachlor doses of 1.1 x 10(-4) and 4.0 x 10(-5) mg/kg-day, respectively, via all potential routes of exposure. The unit cancer risks associated with "internal" dose estimates from human adipose tissue concentrations were calculated and compared with U.S. Environmental Protection Agency (1986a, Carcinogenicity Assessment of Chlordane and Heptachlor/Heptachlor Epoxide, EPA-600/6-87-004) unit risks in air and water. The implications and uncertainties associated with the risk estimates were also discussed.  相似文献   
3.

Background

Seneca Valley virus (SVV-001) is a nonpathogenic oncolytic virus that can be systemically administered and can pass through the blood–brain barrier. We examined its therapeutic efficacy and the mechanism of tumor cell infection in pediatric malignant gliomas.

Methods

In vitro antitumor activities were examined in primary cultures, preformed neurospheres, and self-renewing glioma cells derived from 6 patient tumor orthotopic xenograft mouse models (1 anaplastic astrocytoma and 5 GBM). In vivo therapeutic efficacy was examined by systemic treatment of preformed xenografts in 3 permissive and 2 resistant models. The functional role of sialic acid in mediating SVV-001 infection was investigated using neuraminidase and lectins that cleave or competitively bind to linkage-specific sialic acids.

Results

SVV-001 at a multiplicity of infection of 0.5 to 25 replicated in and effectively killed primary cultures, preformed neurospheres, and self-renewing stemlike single glioma cells derived from 4 of the 6 glioma models in vitro. A single i.v. injection of SVV-001 (5 × 1012 viral particles/kg) led to the infection of orthotopic xenografts without harming normal mouse brain cells, resulting in significantly prolonged survival in all 3 permissive and 1 resistant mouse models (P < .05). Treatment with neuraminidase and competitive binding using lectins specific for α2,3-linked and/or α2,6-linked sialic acid significantly suppressed SVV-001 infectivity (P < .01).

Conclusion

SVV-001 possesses strong antitumor activity against pediatric malignant gliomas and utilizes α2,3-linked and α2,6-linked sialic acids as mediators of tumor cell infection. Our findings support the consideration of SVV-001 for clinical trials in children with malignant glioma.  相似文献   
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This article outlines the motivation and preliminary investigations into a novel method of characterizing cartilage health for potential in vivo application. Current in vivo indentation techniques, which primarily rely on stiffness measurements based on axial data, are unable to adequately distinguish between healthy and degraded tissue. The present in vitro study investigates the effects of controlled artificial degradation on the effective surface stretch, comparing the results with those obtained from the peripheral cartilage surrounding focal osteoarthritis. Results suggest that this technique is highly sensitive, showing a maximum range of 14% effective surface stretch in a normal joint compared with 42% for axial strain measurements. We further demonstrated that the technique can discriminate between degenerative changes and the intrinsic variations in cartilage properties across the normal joint. From these investigations we propose that the relationship between indentation and the in-plane strain field under the indenter can better distinguish degraded tissue than the currently used stiffness techniques.  相似文献   
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Background: Cheiloscopy is a comparatively recent counterpart to the long established dactyloscopic studies. Ethnic variability of these lip groove patterns has not yet been explored.

Aim: This study was a collaborative effort aimed at establishing cheiloscopic variations amongst modern human populations from four geographically and culturally far removed nations: India, Saudi Arabia, Spain and Nigeria.

Subjects and methods: Lip prints from a total of 754 subjects were collected and each was divided into four equal quadrants. The patterns were classified into six regular types (A–F), while some patterns which could not be fitted into the regular ones were segregated into G groups (G-0, G-1, G-2). Furthermore, co-dominance of more than one pattern type in a single quadrant forced us to identify the combination (COM, G-COM) patterns.

Results and conclusion: The remarkable feature noted after compilation of the data included pattern C (a bifurcate/branched prototype extending the entire height of the lip) being a frequent feature of the lips of all the populations studied, save for the Nigerian population in which it was completely absent and which showed a tendency for pattern A (a vertical linear groove) and a significantly higher susceptibility for combination (COM) patterns. Chi-square test and correspondence analysis applied to the frequency of patterns appearing in the defined topographical areas indicated a significant variation for the populations studied.  相似文献   

10.
A prospective study of biological factors for low birthweight (LBW) among UAE nationals in the Al Ain Medical District was undertaken from 15 January 1992 to 14 January 1993, using a case control method. All 293 mothers of LBW infants and an equal number of mothers of the next normal weight infants born after the LBW infant were studied. Of the 3,485 live births, 293 (8.4%) were LBW (less than 2,500 g). Maternal age less than 25 years, lighter weight at booking, nulliparity, first cousin marriage and short interpregnancy interval (IPI) of 3 months or less significantly increased the risk of LBW in this population. After adjusting for other biologic confounders, only low maternal weight and short IPI significantly increased the risk of LBW. Modification of these biologic risk factors would help to reduce the incidence of LBW among the UAE population. © 1996 Wiley-Liss, Inc.  相似文献   
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