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31.
Polymerase chain reaction (PCR)-based methods were used to investigate malaria in pregnant women residing in Yaounde, Cameroon. Microscopy and species-specific PCR-based diagnosis show that at delivery 82.4% of the women were infected with Plasmodium falciparum (27.5% blood-smear positive and 54.9% submicroscopic infections). The prevalence of P. malariae and P. ovale was 7.6% and 2.5%, respectively, with 9.4% infected with more than one species. Based on genotyping of the merozoite surface protein 1 (msp-1) and msp-2 alleles, the mean number of genetically different P. falciparum parasites in peripheral blood was 3.4 (range = 1-9) and 3.5 (range 1-8) in the placenta. Plasmodium falciparum detected by microscopy and PCR as well as mixed-species infections were significantly higher in women < or = 20 years old and paucigravidae, but maternal anemia was associated only with microscopic detection of parasites. Neither submicroscopic infections nor number of parasite genotypes decreased significantly with age or gravidity. Thus, pregnancy-associated immunity helps reduce malaria to submicroscopic levels, but does not reduce the number of circulating parasite genotypes.  相似文献   
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Ulcerative colitis in the tropics   总被引:4,自引:0,他引:4  
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BACKGROUND CONTEXT: Lumbar microdiscectomy is most commonly performed under general anesthesia, which can be associated with several perioperative morbidities including nausea, vomiting, atelectasis, pulmonary aspiration, and prolonged post-anesthesia recovery. It is possible that fewer complications may occur if the procedure is performed under epidural anesthesia. PURPOSE: To investigate the safety and efficacy of epidural anesthesia in elective lumbar microdiscectomies. STUDY DESIGN: A prospective study evaluating the relative morbidities associated with epidural anesthesia and general anesthesia for lumbar microdiscectomy. PATIENT SAMPLE: Forty-three patients scheduled for primary lumbar microdiscectomy. Two cohorts were formed and were studied separately; one observational of all the 43 patients, and a second cohort of 17 patients who agreed to enter in the randomized trial. OUTCOME MEASURES: The clinical outcome was determined by the presence of postoperative pain, the absence of anesthesia-related complications, and the overall postoperative recovery. METHODS: This was a prospective study. With institutional review board approval, 43 consecutive patients were enrolled in the study. However, only 17 patients agreed to be randomized to receive either general or epidural anesthesia for the procedure; the remaining 26 patients selected the type of anesthesia of their preference. Recorded data for all patients included: age; total surgical time; occurrence of nausea, vomiting, atelectasis, or cardiopulmonary complication; ability to arise out of bed on the day of surgery; and the total number of inpatient hospital days. Postoperative pain and satisfaction were assessed only in the randomized cohort. RESULTS: There were a total of 43 patients, with a mean age of 38.1 years. The patients undergoing epidural anesthesia were marginally older than those undergoing general anesthesia. The epidural and general anesthetic groups were not different with respect to surgical time, pain assessed with a linear visual analogue scale, hospital stay, or the likelihood of arising out of bed on the day of surgery. There were no major cardiopulmonary complications in either group. Patients with epidural anesthesia had significantly less nausea and vomiting. CONCLUSIONS: Epidural anesthesia as an alternative to general anesthesia has shown less postoperative nausea and vomiting in lumbar microdiscectomy. Nevertheless, given the small number of patients, this study should be considered as preliminary, showing small differences in minor potential complications.  相似文献   
35.
Tetanus immunisation in the elderly population.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVE--To emphasise that tetanus still occurs in the United Kingdom, particularly in elderly people-as illustrated by two case reports-and to examine the state of tetanus immunity in elderly people. METHODS--111 elderly people (over 65 years) were studied: 43 males, mean age 77.7 years, range 67-94; 68 females, mean age 81.3 years, range 67-95. They were either attending the accident service or were hospital inpatients. An attempt was made to obtain an immunisation history and antitetanus antibody titres were measured. RESULTS--Immunisation history was uncertain and unreliable. Measurement of antibody titres showed that they were inadequate to ensure protection in 50% of those studied. Low levels were particularly prevalent in the over 80 age group and in females. Questioning about military service confirmed that this had predominantly involved males. CONCLUSIONS--Elderly people are at risk of contracting tetanus and should be targeted for community immunisation. Extra precautions in the form of passive immunisation with human anti-tetanus immunoglobulin should be used in this age group in addition to the usual wound management measures when the elderly sustain tetanus prone injuries.  相似文献   
36.
The method of occlusion of the draining bronchus in combination with a one-step percutaneous drainage of the purulent cavity by the Monaldi principle was used in 12 children for the treatment of giant pulmonary abscesses. It was shown that the proposed method unlike traditional procedures allows effective sanitation to be performed. It relieves symptoms of intrathoracic strain and thereby allows avoiding operations at the height of purulent intoxication. No complications and lethality followed the treatment.  相似文献   
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PURPOSE: Multiple trials by the World Health Organization have established levonorgestrel as the gold standard in hormonal emergency contraception (EC). However, changes in menstrual patterns following EC have been observed; thus, we undertook this prospective study to identify and determine the characteristics of these changes. MATERIALS: Women requesting EC at either any of two hospitals --1 family planning unit and 12 pharmacies in Yaoundé, Cameroon were enrolled if they had a history of regular menstrual cycles over the previous 3 months and if they agreed to follow-up until the end of the subsequent menstrual cycle. Pretreatment menstrual patterns were compared with those of the EC treatment cycle and the cycle after EC. RESULTS: In a set of 232 participants (mean age, 25 years), we observed 34 (14.7%) cases of incident intermenstrual bleeding and statistically significant changes in menstrual cycle length, menstrual period length and menstrual appearance compared to baseline patterns that differed according to whether EC was taken well before, close to or well after the expected ovulation for that cycle. The majority of these changes disappeared in the following cycle. CONCLUSION: Levonorgestrel EC is associated with significant but transient changes in menstrual patterns in a significant proportion of users.  相似文献   
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The aetiology of the ultrastructural abnormalities of non-cirrhotic portal fibrosis is not known. In an attempt to elucidate the pathophysiology of this condition, the hepatic ultrastructure in nine cases of non-cirrhotic portal fibrosis with portal hypertension has been studied.  相似文献   
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