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Attaining efficiency in a health care system with a budget constraint involves increasing the utilization of the most cost-effective services. This can be achieved by adjustments to prices, cost curves, or demand curves. In this paper, the potential for demand curve adjustments is examined by selecting two apparently cost-effective services (prenatal care and childhood immunization against tuberculosis), and analyzing the factors explaining their utilization. Data from recent household surveys in Burkina Faso and Niger are used. A multivariate analysis of utilization employs income, price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price variable. Members of certain ethnic groups tend to use the services less, other things being equal. The importance of demand-side factors like ethnicity points to certain kinds of policy interventions like information, education and communication activities which could increase the utilization of cost-effective services.  相似文献   
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We report three cases of pernicious anemia diagnosed in women in Africa. All three women had macrocytic anemia with megaloblasts evident on medullogram. The patients had neurological signs of combined sclerosis and the presence of megaloblasts confirmed the diagnosis of pernicious anemia. All were successfully treated parenterally with vitamins. This disease seems to be underdiagnosed in Africa given the number of cases reported in previous studies.  相似文献   
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Between January 1993 and June 1997, 30 patients with crusted scabies were seen at the dermatological clinic in Dakar (Senegal). Seventeen of these patients were male and 13 were female. Six were children aged 5 to 15 years and 24 were adults aged 18 to 70 years. Diagnosis of crusted scabies was straightforward because this condition, which was rare in Dakar before 1990, has become much more common and is now familiar to Senegalese dermatologists. The infection presented as an extensive scaly or crusted eruption with symmetrical lesions affecting the hands, feet, knees, elbows and ears in particular. Scalp involvement was reported in 25 patients. Erythrodermia was present in 4 cases and pachyonychia in 4 cases. Twenty-seven of the 30 patients had moderate or severe pruritus, whereas an absence of pruritus is regarded as a classical characteristic of crusted scabies. Diagnosis was readily confirmed by examination of hyperkeratotic material under the microscope: numerous mites and eggs were present. The two most common etiological factors were auto-immune diseases (6 cases, 4 of whom were receiving no steroid or other immunosuppressive treatment at the time of onset of crusted scabies) and malnutrition (5 of the 6 children in the study). The other associated conditions identified were: physical debilitation (4 cases), HIV infection (3), mental disability-Down's syndrome (3) and long term use of topical steroids for artificial depigmentation (2). Two patients were immunocompetent and 5 patients died shortly after diagnosis, before any underlying conditions could be identified. Seven patients were cured with benzyl benzoate. Seven others, all adults, received a single oral dose of ivermectin (200 mg/kg) and topical kerolytic drugs. Ivermectin was ineffective in 1 case, and an improvement was observed in another case, although a complete cure was achieved only after a second dose. The other patients were all cured and showed no signs of scabies one month after ivermectin treatment. A recurrence was observed in 3 patients a few months later however, suggesting that these patients were reinfected. No side effects were reported in any of the patients treated with ivermectin.  相似文献   
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A Plasmapore-coated titanium alloy block was implanted in ewes for the purpose of providing interbody fusion. Four blocks were implanted in each ewe: one uncoated block (without Plasmapore) serving as a reference specimen and three blocks coated with Plasmapore. Mechanical testing and histological study were performed on five ewes. OBJECTIVES: Determination of the quality of the mechanical and histological anchorage of the Plasmapore implanted in the interbody space in the same animal living under conditions of physical strain exerted on the spine. METHODS: Four months after surgical implantation of the block, the ewes were sacrificed: the removed spines were frozen for subsequent mechanical analysis and preserved in a solution of 40 degrees alcohol for subsequent histological analysis. X-rays were taken to evaluate the positioning of the implant. The mechanical analysis included extraction tests, measuring the maximum extraction force and evaluating the stiffness of the system, being indicative of the mechanical fixation quality. The histological study included both qualitative and quantitative analysis, together with an evaluation of the osteointegration of the blocks coated with Plasmapore. RESULTS: After 4 months of implantation, a mean extraction force of 990 N was necessary for the blocks coated with Plasmapore, and of 1.338 N for the blocks coated with Plasmapore with additional osteosynthesis, whereas a mean extraction force of 332 N was necessary for the uncoated blocks. Anchorage and resistance against uprooting of the blocks coated with Plasmapore were significantly more efficient. The histological study revealed the presence of bone neoformation adhering to the implant. Quantification of this bone formation covering nearly 45% of the implant perimeter, confirmed both osteointegration of the implant perimeter, confirmed both osteointegration of the implant surfaces being in contact with the vertebral endplates and osteoconduction along the lateral surfaces. CONCLUSION: The titanium Plasmapore block enables interbody fusion due to an osteointegration of the vertebral endplates by Plasmapore coating, which was proved by the results of extraction testing and histological study. It should be taken into account that no additional bone grafts have been used and that the implant had not been forced into the spongiosa.  相似文献   
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Several studies have suggested that rheumatoid arthritis (RA) is uncommon in rural sub-Saharan Africa. The aim of this study is to determine the potential differences between patients with RA living in rural areas and those living in urban areas. We performed a cross-sectional study from June 2006 to May 2009. We included all patients with RA (1987 ACR criteria) seen at the Rheumatology Unit of the Le Dantec Teaching Hospital, Dakar, Senegal. We compared the main socio-demographic and clinical characteristics of patients living in rural areas to those living in urban areas. We included 180 patients in our study, of whom, 143 (79.4?%) lived in urban areas and 37 (20.6?%) in rural areas. The median age was 44?years [range 34–55] in patients from rural areas vs. 41?years [range 30–53] in patients from urban areas, without any statistical significance (p?=?0.24). Patients under the age of 60 mostly lived in urban areas (p?=?0.03). The extra-articular manifestations were significantly more frequent in patients living in rural areas (p?=?0.02). There was no statistical significance when comparing the delay in diagnosis, number of swollen joints, disease activity, hand deformities, and concentration of autoantibodies (RF and ACPA) in both populations. The percentage of patients seen from the rural areas of Senegal is low (20.6?%) compared to those seen from the urban areas. The number of extra-articular manifestations is the main difference between patients living in rural and urban areas. The role played by environmental factors seems important. Further incidence studies are needed.  相似文献   
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