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991.
The results of a community-based survey on knowledge and beliefs about tuberculosis in non-working women are presented. The women in the sample showed a very good knowledge of the important aspects of tuberculosis: 90% were aware that it is a problem in their area; 97% knew that it affects the chest; 94% said that it could be fatal; 85% considered it to be infectious and 88% knew that the local clinic provided treatment. Their knowledge of symptoms was good overall but the study revealed misconceptions about the causes and transmission of tuberculosis; 16% indicated that they would not be keen to associate with people with tuberculosis owing to fear of infection. The design effect of cluster sampling was considered in the analysis. The highest design effects (i.e. the most clustering of responses) were found for responses to questions on the causes of tuberculosis and places where treatment could be obtained, possibly reflecting that these beliefs are influenced by neighbourhood contacts. Future tuberculosis education in this group needs to build on existing knowledge and awareness and should focus on changing attitudes such as misconceptions about transmission and the stigmatisation of the disease. Health workers face the challenge of changing behaviour in this community to ensure that people with symptoms present early for screening and that people diagnosed as having tuberculosis comply with treatment.  相似文献   
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994.
Extrarenal Wilms tumor occurring in the inguinal canal   总被引:2,自引:0,他引:2  
We report an unusual case of extrarenal Wilms tumor discovered incidentally during routine inguinal orchiopexy. The world literature and embryological implications of Wilms tumor in the inguinal canal are reviewed.  相似文献   
995.
Two cases of progressive, occipital lancinating pain and dysesthesias associated with a sensory deficit of the C2 dermatome are presented. Symptoms were relieved, and C2 sensory function restored by releasing a hypertrophied atlanto-epistrophic ligament entrapping the C2 root and ganglion. The normal anatomy and abnormal surgical findings are described. C2 entrapment by the atlanto-epistrophic ligament is discussed in reference to other C2 lesions causing occipital pain. We conclude that some patients whose progressive occipital pain is accompanied by a C2 sensory deficit are suffering from entrapment of the C2 root and ganglion amenable to surgical decompression.  相似文献   
996.
W L Young  I Prohovnik  E Ornstein  N Ostapkovich  M B Sisti  R A Solomon  B M Stein 《Neurosurgery》1990,27(2):257-66; discussion 266-7
To investigate the cerebral hemodynamic changes associated with obliteration of arteriovenous malformations (AVMs), we studied 26 patients undergoing total microsurgical AVM resection during isoflurane and N2/O2 anesthesia. Detectors were placed 5 to 6 cm from the margin of the lesion and in a homologous contralateral position. Cerebral blood flow (CBF) was measured using the intravenous xenon-133 technique before and after AVM resection, during both hypocapnia and normocapnia at each stage. Intraoperative changes in CBF were related to a risk score system based on the patient's history and preoperative angiograms. Seven otherwise healthy patients undergoing spinal surgery were studied to control for anesthetic effects. Patient demographic and clinical data for the AVM group conformed to the expected strata of a large AVM population. The CBF increased after excision (22 +/- 1 ml/100 g/min before excision to 30 +/- 2 ml/100 g/min after excision; mean +/- SE, n = 25, P less than 0.002) without a hemispheric difference. CO2 reactivity increased slightly after excision (4.2 +/- 0.3% change/mm Hg before excision to 4.7 +/- 0.3% change/mm Hg after excision; n = 14, P less than 0.02). The baseline CBF and CO2 reactivity were not different from the control group. There was a weak correlation between the risk score and the percentage of change in the ipsilateral CBF, with a trend for the patients with the lowest risk to have the lowest CBF changes after resection. There was no relationship between CO2 reactivity and risk grade. None of the patients awoke from anesthesia with unexpected neurological deficits. The highest CBF increases were associated with postoperative brain swelling in one patient and fatal intracerebral hemorrhage in another. Both patients had normal CO2 reactivity before excision. One patient suffered postoperative intracerebral hemorrhage, attributable to technical problems, and had no increase in CBF. We conclude that, with an acute increase in the arteriovenous pressure gradient (and cerebral perfusion pressure) that results from shunt obliteration, there is an immediate global effect of AVM resection to increase CBF. Cerebrovascular reactivity to CO2 remains intact both before and after excision.  相似文献   
997.
Contact lens disinfection systems were evaluated for their effectiveness in killing Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites and cysts. Amoebae were inoculated into commercially available contact lens cleaning and soaking solutions. At intervals varying from 30 minutes to 24 hours, solutions were filtered. The filters were removed and cultured for Acanthamoeba organisms. Striking differences were observed in the abilities of the different disinfecting solutions to kill the organisms. Solutions containing chlorhexidine were effective at very short exposure times. Solutions containing benzalkonium chloride required slightly longer exposure times but were faster than solutions containing only thimerosal. Solutions containing sorbate, polyaminopropyl biguanide, or polyquaternium-1 were not effective at killing Acanthamoeba organisms in the time allotted for the experiment. Solutions containing hydrogen peroxide were quite effective if the agent was not prematurely catalyzed. A. polyphaga generally required longer exposure to disinfectants than did A. castellanii for complete inhibition to occur.  相似文献   
998.
999.
1000.
The long-stem bipolar prosthesis in surgery of the hip   总被引:2,自引:0,他引:2  
More than 500 hips, with either displaced fractures of the femoral neck or primary or revision total hip arthroplasty, were treated by a straight, long-stem (305-mm), Bateman-type bipolar model (BBM). The BBM was not porous coated, and it is not cemented in place. The femoral component is secured in the femoral canal by means of biomechanical fixation. It is biologic by bone ingrowth through the fenestration in the proximal neck. It is mechanical by a snug fit in the isthmus and by three-point fixation within the shaft. The removed femoral head is morselized in the bone mill and packed into the prepared femoral canal to enhance a tight fit. The collar of the BBM transfers stress to the calcar. Postoperative roentgenograms show incorporation of bone graft within the fenestration of the prosthesis and no stress shielding of the calcar. The acetabulum requires reaming only if it is shallow or asymmetric. It usually presents no problem except in revision total hip arthroplasty. The present authors have used the BBM almost exclusively since 1981. After eight years, the BBM has stood up well to the test of time and presented few major problems.  相似文献   
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