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61.
Vertical transmission of yellow fever virus from orally infected females to their progeny was experimentally demonstrated in 2 Aedes aegypti colonies from the Dakar and Koungheul regions in Senegal. A total of 10,530 F1 adult mosquito progeny were tested. The overall vertical transmission rate was 0.97%, with no significant difference between the Dakar and Koungheul colonies. The infection rates were significantly higher in females (1.15%) than in males (0.74%) in both colonies. The virus was not isolated from the progeny of the first oviposition cycle (OVC1). The true infection rates were 0.27% and 1.99%, respectively, for the OVC2 and OVC3 progeny in the Dakar colony, and 1.1% and 1.48%, respectively, for the OVC2 and OVC3 progeny in the Koungheul colony. The infection rates increased with extrinsic incubation in both male and female offspring of the 2 colonies, reaching 5.2% in 20-day-old OVC3 female progeny in the Dakar colony. The epidemiologic consequences of these results are discussed.  相似文献   
62.
Missed opportunities and inappropriately time immunization substantially reduced the coverage achieved in Mozambique and Guinea Conakry. During coverage surveys in Mozambique, we noted dates of attendance at a health facility for growth monitoring or vaccination, and in Conakry we also abstracted dates of curative care visits from home-based documents. In Mozambique, an average of 84 per cent of children aged 12-23 months had documents, and an average of 53 per cent of children were fully and correctly vaccinated. Among children with cards, 11 per cent had received all vaccines, but at least one dose was applied before the recommended age or with too short an interval between doses (inappropriately timed vaccinations). A further 8 per cent of children had sufficient documented contacts with preventive services to be fully vaccinated, but immunization opportunities had been missed. In Conakry, 54 per cent of 12-23 month-old children had immunization cards, and only 19 per cent were fully and correctly vaccinated. Among children with cards, 9 per cent had received all vaccines, but some were inappropriately timed, and 19 per cent had enough contacts with curative or preventative services to be fully vaccinated, but opportunities had been missed. We recommend that home-based records document all health centre visits, including those for curative care, and that missed opportunities and vaccination timing be routinely evaluated during vaccine coverage surveys.  相似文献   
63.
Methotrexate (MTX), which has been used for years in cancer treatment, is now being proposed as a first-line treatment for rheumatoid arthritis (RA), despite its potential side effects. The aim of this study was to investigate the short-term efficacy, safety and relative cost of low-dose MTX for the treatment of RA. We carried out an open, nonrandomized trial in which patients received a 7 mg injection of MTX once per week, with clinical and biological follow up. A single physician performed the weekly assessments, which involved evaluation of the duration of morning stiffness, the number of night awakenings, the number of painful and swollen joints and Ritchie's index. Blood cell count and erythrocyte sedimentation rate were determined monthly. Twelve RA patients were enrolled in the trial, over a mean treatment period of 356 +/- 175 days. A significant improvement was observed in all variables except the number of swollen joints. Ritchie's index decreased from a mean of 31.8 +/- 11.85 to 6.5 +/- 8.98 (p<1.6 x 10- 4). Minor adverse reactions were observed but none indicated treatment withdrawal: 6 cases of nausea, 2 of a moderate increase in transaminase activity, 1 of bronchitis, in which the responsibility of MTX was not definitely established and 3 cases in which hemoglobin levels decreased. The monthly cost of the treatment, including the drug itself and laboratory tests, is lower than that of gold salt injection. Three issues of key importance in our region were investigated in this study: 1) the possible desire to become pregnant of female patients undergoing MTX treatment. In addition, some of the young and unmarried patients did not understand or appreciate the contraceptive effects of the treatment; 2) poor compliance with the treatment due to limited financial resources. Many patients did not regularly attend for their follow-up appointments and many stopped taking the medication. One third of the patients were lost to follow-up during this study; 3) the prevalence of chronic hepatitis, which may limit the use of MTX in our region. Serological tests should be performed before the treatment is started and a liver biopsy is recommended for patients with chronic hepatitis B or C.  相似文献   
64.
The Institute for Health and Development (ISED) at the University of Dakar, was created in 1987. Its mission is to fulfill the public health training needs of Senegalese health care professionals. ISED is responsible for a training program entitled "Certificat d'études Spéciales" (CES), the equivalent of a Masters of Public Health degree. The "CES" is a two-year program comprised of six modules, which last four months each. The ISED training approach stresses trainee responsibility above all. It is based on the trainee's professional tasks and is oriented toward the problems identified by the trainees themselves. In this sense it is highly adaptive and flexible. Each module is implemented in the same way; initially there is a 15 day residential phase for intensive theoretical courses, followed by an application period of 75 days in the trainee's work place, and then a final residential phase of 15 days for writing and presenting a technical report on the work in the field. This model allows trainees to bring together the theoretical and the practical. The trainers directly supervise each of these three phases. The two residential phases are conducted in the ISED training center, located in Mbour, 80 Km south of Dakar. 103 trainees are enrolled in the program in seven different classes. Of these trainees, 93 are health care specialists (85 physicians 7 pharmacists, 1 dentist). Ninety percent of previous graduates have been civil servants who work for the Ministry of Health in Senegal and the remaining 10% were from Burkina Faso and Togo. The training program is considered by all stockholders, beneficiaries, and relevant financial institutions, to be appropriate, beneficial and successful.  相似文献   
65.
It is of particular concern to evaluate the risk of lung cancer occurrence after breast cancer treatment as women with breast cancer quite often undergo radiation therapy as part of their initial treatment and their life expectancy remains long. From a roster of 7711 women initially treated for breast cancer between 1954 and 1984, a cohort-study was performed among 4171 1-year survivors followed during the period 1975-1995. The relationship between the radiation dose received by the lung and the risk of lung cancer was then evaluated in a nested case-control study of 11 breast-cancer patients who developed lung cancer and 22 controls matched for age at diagnosis of breast cancer, period of initial treatment and length of follow-up. Among the 4171 women, six developed lung cancer during the entire follow-up as compared to 5.4 cases expected (SIR = 1.1, 95% CI: 0.4-2.3). When considering only the women initially treated by radiotherapy with or without adjunction of chemotherapy and excluding the 10 first years of follow-up, the SIR was significantly increased (SIR = 3.2, 95%CI: 1.0-7.4). In the case-control study, nine of the 11 lung cancers occurred in the ipsilateral lung and two in the trachea. The overall odds ratio (OR) of lung cancer associated with initial radiotherapy was 1.4 (95% CI: 0.2-11.1) and an excess in the OR of 7% (90% CI: ? to 41%, p = 0.10) per gray delivered to the site of lung cancer was evidenced. Our results agree with previous studies in favor of an increased risk of lung cancer after radiation therapy for breast cancer.  相似文献   
66.
To document the actual genetic diversity of HIV-1 strains in the Republic of Congo, 114 HIV-1 positives persons were sampled in 2003 and 2004 after their informed consent. They were attending the teaching hospital, the reference health center in Makelekele, Brazzaville and the regional hospital centers in Pointe-Noire, Gamboma and Ouesso. A total of 104 samples were genetically characterized by direct sequencing of the p24 gag region and 80 were also subtyped in the V3-V5 env region. The genetic subtype distribution of the Congolese strains showed the predominance of subtype A (36.5% and 32.5% in gag and env, respectively) and G (30.8% and 21.25%), whereas subtype D strains represented 12.5% and 15%. Subtypes C, F, H, J, K and the CRFs-01, -02, -05 -06, and also the recently characterized CRF18 were seen at lower rates. Finally, 4.8% (gag) and 6.25% (env) of the strains could not be classified. Moreover, a high intra-subtype diversity was observed in our study. Among 70 strains which have been characterized in the two genomic regions, 14 (20%) appeared to be unique recombinants. These data show a high genetic variability in the Republic of Congo, where all the subtypes have been documented together with certain subsubtypes and several CRFs.  相似文献   
67.
Metabolic activation of the hepatocarcinogenic mycotoxin aflatoxin B(1) (AFB(1)) results in the covalent attachment of AFB(1) to serum albumin. Digestion of adducted albumin releases AFB(1)-lysine, a biomarker of exposure status. AF-albumin adducts have been most frequently measured in precipitated serum albumin using an immunoassay (ELISA); however, a sensitive and specific isotope dilution mass spectrometric (IDMS) assay for measurement of AFB(1)-lysine in serum has recently been developed. The ELISA and IDMS methods were compared using 20 human sera collected in Guinea, West Africa, where AF exposure is endemic. Measurement of AFB(1)-lysine adduct concentrations by IDMS in serum and albumin precipitated from the same sample revealed that precipitation has no effect on the measured adduct levels. The concentration of AF-albumin adducts measured by ELISA and AFB(1)-lysine measured by IDMS in 2 mg of albumin were well correlated (R = 0.88, P < 0.0001); however, AF-albumin adduct concentrations measured by ELISA were on average 2.6-fold greater than those of the AFB(1)-lysine adduct. Although these data suggest that the ELISA is measuring other AF adducts in addition to AFB(1)-lysine, these biomarkers are comparable in their ability to assess AF exposure at AF-albumin concentrations > or =3 pg AFB(1)-lysine equivalents/mg albumin. Identification of other adducts may clarify the mechanistic basis for using AF-protein biomarkers to assess exposure status in future epidemiologic studies of liver cancer.  相似文献   
68.
The authors report a series of 157 stenoses of the urethra treated by endoscopic urethrotomy between 1991 and 1997. After a first urethrotomy the success rate is 51.8%, with a decline of one year. Mortality is zero, and the morbidity assessed at 9%. For these authors, the result is better when the urethrotomy concerns an uninfected, one-time, short (less than 2 cm) stenosis, whatever the etiology, located on the proximal urethra. The duration of the postoperatory catheter has been fixed at three days. Poor results (35.20%) have been reported in stretched stenoses located on the distal urethra. These poor results have been treated by another urethrotomy, with 25% good results. The remaining 10.2% have needed sessions of urethral dilatation, even a plasty.  相似文献   
69.
Thirteen cases of genital tuberculosis are reported to make emphasis onto the difficulties of diagnosis, management and prognosis of the disease. The average age of the patients is 31 years. Most of them were under 30. The circumstances of diagnosis were variable. The diagnosis was essentially made thanks to histology. The evolution was favorable under antibiotics. But clinical sequels as amenorrhea and infertility are frequent.  相似文献   
70.
Objectives and methods.The risk of second primary malignancies (SMN) was studied in a cohort of 4,416 one-year survivors of a breast cancer. The role of the menopausal status and of the initial treatment modalities (surgery, radiotherapy, and chemotherapy) was investigated. Results.Excluding second primary breast cancer and non-melanoma skin cancer, a total of 193 (4.4%) patients developed a SMN between 1973 and 1992, compared with 136 expected (Standardised Incidence Ratio, SIR=1.4, 95% CI (1.2–1.6)). No trend towards either an increase or a decrease was noted in the SIR with time after treatment (p=0.2). The greatest increase in the relative risk concerned soft tissue cancers (SIR=13.0, 95% CI: 6.8–22.3), followed by leukaemia (SIR=3.1, 95% CI: 1.7–5.0), melanoma (SIR = 2.7, 95% CI: 1.4–4.8), kidney (SIR=2.5, 95% CI: 1.2–4.5), ovary (SIR=2.0, 95% CI: 1.2–3.1) and uterine tumours (SIR=1.9, 95% CI: 1.4–2.5). The SIR was 3.0 (95% CI 1.8–4.7) in women under 40 at the time of the breast cancer, 1.9 (95% CI : 1.4 – 2.4) in those aged 40–49 and 1.2 (95% CI 1.0–1.4) in those aged 50 or more. In the 2,514 women who had received radiotherapy as initial treatment without chemotherapy, the SIR for all SMN was 1.6 (95% CI: 1.1–2.3) fold higher than in those who had not received radiotherapy as initial treatment. Conclusion.In conclusion, this study confirms the increased risk of second malignancies in women treated for a breast cancer, and particularly in those who were younger at the time of treatment for breast cancer. Our results also suggest that radiotherapy may play a role in the onset of these second lesions.  相似文献   
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