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171.
Recent reviews of intervention efforts aimed at ending female genital cutting (FGC) have concluded that progress to date has been slow, and call for more efficient programs informed by theories on behavior change. Social convention theory, first proposed by Mackie (1996), posits that in the context of extreme resource inequality, FGC emerged as a means of securing a better marriage by signaling fidelity, and subsequently spread to become a prerequisite for marriage for all women. Change is predicted to result from coordinated abandonment in intermarrying groups so as to preserve a marriage market for uncircumcised girls. While this theory fits well with many general observations of FGC, there have been few attempts to systematically test the theory. We use data from a three year mixed-method study of behavior change that began in 2004 in Senegal and The Gambia to explicitly test predictions generated by social convention theory. Analyses of 300 in-depth interviews, 28 focus group discussions, and survey data from 1220 women show that FGC is most often only indirectly related to marriageability via concerns over preserving virginity. Instead we find strong evidence for an alternative convention, namely a peer convention. We propose that being circumcised serves as a signal to other circumcised women that a girl or woman has been trained to respect the authority of her circumcised elders and is worthy of inclusion in their social network. In this manner, FGC facilitates the accumulation of social capital by younger women and of power and prestige by elder women. Based on this new evidence and reinterpretation of social convention theory, we suggest that interventions aimed at eliminating FGC should target women's social networks, which are intergenerational, and include both men and women. Our findings support Mackie's assertion that expectations regarding FGC are interdependent; change must therefore be coordinated among interconnected members of social networks.  相似文献   
172.
The in vitro hepatoprotective effect of the methanolic extract from Ficus gnaphalocarpa (Miq.) Steud. ex A. Rich (Moraceae) on the CCl?-induced liver cell damage as well as the possible antioxidant mechanisms involved in this protective effect, were investigated. The phytochemical investigation of this methanolic extract led to the isolation of six compounds identified as: betulinic acid (1); 3-methoxyquercetin (2); catechin (3); epicatechin (4); quercetin (5); and quercitrin (6). The hepatoprotective activity of these compounds was tested in vitro against CCl?-induced damage in rat hepatoma cells. In addition, radical-scavenging activity, β-carotene-linoleic acid model system, ferric-reducing antioxidant parameter and microsomal lipid peroxidation assays were used to measure antioxidant activity of crude extract and isolated compounds. Silymarin and trolox were used as standard references and, respectively, exhibited significant hepatoprotective and antioxidant activities. (5), (6) and (2) showed significant antioxidant and hepatoprotective activities as indicated by their ability to prevent liver cell death and lactate dehydrogenase leakage during CCl? intoxication. These results suggest that the protective effects of crude extract of F. gnaphalocarpa against the CCl?-induced hepatotoxicity possibly involve the antioxidant effect of these compounds.  相似文献   
173.
174.
Diabetes is the most common metabolic disorder worldwide and is a major public health problem. Its frequency increases every day in all countries. However, in developing African countries, few people have access to drugs. In addition, in Africa, traditional beliefs induce people to use medicinal plants whenever they have health problems. Thus, many people in these developing countries use plants for the treatment of diabetes. Yet, few studies are focused on the knowledge and attitudes of the users on medicinal plants in Africa in general and in Senegal in particular. Hence we undertook this survey on the use of medicinal plants for the treatment of diabetes in Senegal in order to make recommendations which could contribute to the increase of the value of herbal medicines in developing countries. We did a cross-sectional survey by direct interview at a university teaching hospital, in Dakar with a representative sample of 220 patients. Forty-one plants were used by the patients and the two most frequently cited were Moringa oleifera Lam (65.90%) and Sclerocarya birrea (A. Rich) Hochst (43.20%). Patients gave several reasons for using medicinal plants (traditional treatment: 40%, efficacy: 32%, low cost: 20%). The principal suppliers of plants were tradesmen in the market (66.8%) and traditional therapists (5%). Sixty-five per cent of patients think that medicinal plants are efficient for the treatment of diabetes and 20% have reported adverse effects which could be caused by medicinal plants. In conclusion, many people in our study think that medicinal plants are efficient for the treatment of diabetes, which requires research work by scientists in developing countries in this field in order to prove their efficacy and innocuousness.  相似文献   
175.
We reported that the combination of reactive oxygen species (ROS) quenchers Mn(III) tetrakis (4-benzoic acid) porphyrin (MnTBAP), catalase, and glutathione (MCG) given before 2 hours cold ischemia better protected cardiac mitochondria against cold ischemia and warm reperfusion (IR)-induced damage than MnTBAP alone. Here, we hypothesize that high K(+) cardioplegia (CP) plus MCG would provide added protection of mitochondrial bioenergetics and cardiac function against IR injury. Using fluorescence spectrophotometry, we monitored redox balance, ie reduced nicotinamide adenine dinucleotide and flavin adenine dinucleotide (NADH/FAD), superoxide (O(2) (?-)), and mitochondrial Ca(2+) (m[Ca(2+)]) in the left ventricular free wall. Guinea pig isolated hearts were perfused with either Krebs Ringer's (KR) solution, CP, or CP + MCG, before and during 27°C perfusion followed immediately by 2 hours of global ischemia at 27°C. Drugs were washed out with KR at the onset of 2 hours 37°C reperfusion. After 120 minutes warm reperfusion, myocardial infarction was lowest in the CP + MCG group and highest in the KR group. Developed left ventricular pressure recovery was similar in CP and CP + MCG and was better than in the KR group. O(2) (?-), m[Ca(2+)], and NADH/FAD were significantly different between the treatment and KR groups. O(2) (?-) was lower in CP + MCG than in the CP group. This study suggests that CP and ROS quenchers act in parallel to improve mitochondrial function and to provide protection against IR injury at 27°C.  相似文献   
176.
In this survey, 213 patients in an antiretroviral treatment programme in Phnom Penh, Cambodia, were tested for GB virus C (GBV-C) RNA before treatment initiation. Most had advanced HIV infection, only 34 having CD4 cell counts > 200 cells/microl. GBV-C-RNA was detected in 35 patients. The proportion with positive GBV-C-RNA decreased dramatically with CD4 cell counts < 100 cells/microl. In multivariate analysis, low CD4 cell counts, tuberculosis, anaemia, and traditional medicine were independently and negatively associated with GBV-C-RNA detection.  相似文献   
177.

Ethnopharmacological relevance

The leaves of Crassocephalum bauchiense have long been used in traditional Cameroonian medicine for the treatment of epilepsy, pain, inflammatory disorders, arthritis and intestinal pain.

Aim of the study

In this study, we attempted to identify the possible antinociceptive action of the aqueous extract and the alkaloid fraction prepared from the leaves of Crassocephalum baucheiense.

Materials and methods

Using acetic acid induced abdominal constrictions, formalin-, capsaisin- and glutamate-induced nociception, and hot plate assay procedures, the antinociceptive effects of the aqueous extract and the alkaloid fraction was assessed after oral administration in mice. Morphine sulfate was used as reference analgesic agent. Mice were submitted to the rota-rod task and open-field test in order to assess any non-specific muscle-relaxant or sedative effects of the extracts of Crassocephalum bauchiense. Male and female Swiss mice were used to assess acute toxicity of these extracts.

Results

The aqueous extract and the alkaloid fraction of Crassocephalum bauchiense produced a significant antinociceptive effects in the acetic acid, formalin, glutamate, capsaicin and hot plate tests. These antinociceptive effects of Crassocephalum bauchiense were significantly attenuated by pretreatment with naloxone. The extracts of Crassocephalum bauchiense did not alter the locomotion of animals in the open-field or rotarod tests, which suggest a lack of a central depressant effect. The animals did not exhibit any acute toxicity to the aqueous extract and the alkaloid fraction, so it was not possible to calculate the LD50.

Conclusion

The results confirm the popular use of Crassocephalum bauchiense as an antinociceptive, and contribute to the pharmacological knowledge of this species because it was shown that the aqueous extract and the alkaloid fraction of Crassocephalum bauchiense produced dose related antinociception in models of chemical and thermal nociception through mechanisms that involve an interaction with opioidergic pathway.  相似文献   
178.
Wastewater of human and animal may contain Shiga toxin-producing (STEC) and enteropathogenic (EPEC) Escherichia coli. We evaluated the prevalence of such strains in a wastewater treatment plant (WWTP) receiving both city and slaughterhouse wastewater. PCR screenings were performed on 12,248 E. coli isolates. The prevalence of STEC in city wastewater, slaughterhouse wastewater and treated effluent was 0.22%, 0.07% and 0.22%, respectively. The prevalence of EPEC at the same sampling sites was 0.63%, 0.90% and 0.55%. No significant difference was observed between the sampling points. Treatment had no impact on these prevalences. Enterohemorrhagic E. coli (EHEC) O157:H7 and O111:H8 were isolated from the treated effluent rejected into the river. The characteristics of STEC and EPEC differed according to their origin. City wastewater contained STEC with various stx subtypes associated with serious human disease, whereas slaughterhouse wastewater contained exclusively STEC with stx2e subtype. All the EPEC strains were classified as atypical and were screened for the ε, γ1 and β1 subtypes, known to be associated with the EHEC mainly involved in human infections in France. In city wastewater, eae subtypes remained largely unidentified; whereas eae-β1 was the most frequent subtype in slaughterhouse wastewater. Moreover, the EPEC isolated from slaughterhouse wastewater were positive for other EHEC-associated virulence markers, including top five serotypes, the ehxA gene, putative adherence genes and OI-122 associated genes. The possibility that city wastewater could contain a pool of stx genes associated with human disease and that slaughterhouse wastewater could contain a pool of EPEC sharing similar virulence genes with EHEC, was highlighted. Mixing of such strains in WWTP could lead to the emergence of EHEC by horizontal gene transfer.  相似文献   
179.
Presentation of pyrosequencing data and phylogenetic analysis for the full genome of Ntaya virus, type virus of the Ntaya virus group of the Flaviviridae isolated in Cameroon in 1966.  相似文献   
180.
BackgroundPneumonia is a main cause of under-five mortality in low-income settings. The pneumococcal conjugate vaccine (PCV) has been introduced in many countries as a tool in the disease''s prevention. Although PCV''s effectiveness has been established, less is known about the effects of introducing additional injectable vaccines into routine immunisation programmes, particularly in the context of resource-constrained settings.ObjectivesTo explore the effects of PCV introduction on the immunisation programmes and health systems in four low-income countries.MethodsThis study was carried out in Cameroon, Ethiopia, Kenya and Mali. Three to four regions and nine to 10 districts were selected within each country. Semi-structured interviews were carried out at national, regional and district levels (n=173). Researcher-administered questionnaires were completed with facility staff (n=124). Routine data on monthly vaccination activities were collected at district and facility levels.ResultsPCV was generally well integrated into existing routine immunisation. Little or no impact was found in most areas of the health systems. Some minor effects were found on immunisation programmes, particularly in areas with either planning activities or investments e.g. staff skills were strengthened and there were limited improvements in surveillance. Although health sector workers perceived increases in the coverage of other vaccines following the introduction of PCV, routine service data did not confirm this claim. No substantial impacts were seen in health system management, service delivery or performance.ConclusionsThe introduction of PCV had marginal impacts on the Expanded Programme for Immunisation and little to none on broader health systems.  相似文献   
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