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Although classified by the Joint Monitoring Programme (JMP) as unimproved sanitation facilities, public toilets still play a critical role in eliminating open defecation in informal settlements. We explored perspectives of toilet operators on opportunities and barriers to operation and maintenance (O&M) of public toilets in informal settlements. A cross-sectional study design was used. Up to 20 in-depth interviews were used to obtain data on the experiences of public toilet operators. Thematic content analysis was used.

Ressults show that opportunities for improving O&M include; operation of public toilets is a source of livelihood; operators are knowledgeable on occupational risks, and the community is involvedin sanitation activities. Barriers to effective O&M include; high operation costs, failure to break even and a lack of investments in occupational health Therefore, there is need to recognise the significance of public toilets as a viable alternative to open defecation in areas where ownership of private sanitation facilities is difficult. Failure to observe the health and safety of toilet operators may further compromise O&M.  相似文献   

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Passenger leukocytes have been suggested to be both pro-tolerant and immunogenic. The opportunity to evaluate the role of allogeneic passenger leukocytes in humans was presented by a 47-year-old man who donated bone marrow to his HLA-identical leukemic sister. Eleven years later he developed renal failure. The sister's marrow was noted to be 100% XY karyotype and free of malignancy. She donated a kidney to her brother. Immunosuppression was tapered following transplantation. After 6 months, the recipient was on monotherapy sirolimus, 1 mg every third day. A surveillance biopsy was normal and sirolimus was stopped. Eight weeks later, he presented with severe rejection that reversed with Thymoglobulin. Renal function returned to baseline and has been stable on conventional immunosuppression.  相似文献   
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OBJECTIVE: The understanding of pathophysiology and cellular mechanisms of chronic heart failure requires the creation of appropriate and accurately characterized animal models, thus enabling meaningful evaluation of evolving medical and surgical therapies. METHODS: The left anterior descending and its diagonal branch were ligated in 12 sheep to induce left ventricular dysfunction. RESULTS: Study of left ventricular pressure-volume loops 3 months post-operatively showed a significant deterioration of both systolic and diastolic indexes of left ventricular function. The left ventricular end-diastolic pressure increased from 3+/-1 to 7+/-1 mmHg (P<0.001) along with a substantial increase in end-diastolic volume from 78+/-8 to 121+/-6 ml (P=0.002) and a significant decrease in cardiac output from 2+/-0.2 to 1.5+/-0.2 l/min (P=0.001). The left ventricular end-systolic pressure-volume relationship deteriorated from 2.7+/-0.37 to 0.7+/-0.16 mmHg/ml (P=0.0002) along with a significant reduction in the pre-load recruitable stroke work (P=0.001). The ejection fraction decreased from 34+/-2% to 16+/-4% (P<0.001) with a significant decrease in +dp/dt and -dp/dt (P=0.009). The mean systemic blood pressure, however, was maintained due to a substantial increase in the systemic vascular resistance (P=0.007). CONCLUSION: This study describes a reproducible large animal model of left ventricular dysfunction. This model is potentially useful to study the pathogenesis of remodelling, surgical management of heart failure and development of novel treatment strategies.  相似文献   
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Strut fixation of an extensive flail chest   总被引:2,自引:0,他引:2  
The indications for and preferred approaches to operative stabilization of posttraumatic chest wall instability are uncertain. We suggest this simple, rapid, and effective approach to surgical stabilization by Luque rod strutting of the flail segment when operation is required.  相似文献   
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Advances in endoscopic surgical equipment and laser technology have expanded the role of thoracoscopy to include thoracoscopic pulmonary resection. Eighty-five thoracoscopic pulmonary resections were performed on 61 consecutive patients with small lesions (less than 3 cm) in the outer third of the lung. Patients with preoperative histologic evidence of bronchogenic carcinoma were excluded unless there was impairment of cardiopulmonary function, advanced age, or concomitant extrathoracic malignancy. These thoracoscopic pulmonary resections were accomplished with the neodymium:yttrium-aluminum garnet laser (31), endoscopic stapler (29), or both (25). The mean diameter of the lesions was 1.3 cm (range, 0.4 to 2.7 cm). There has been one late death (38th postoperative day) unrelated to the operation. Morbidity consisted of postoperative atelectasis (2), pneumonia (2), bleeding requiring transfusion (1), and bronchopleural fistula of greater than 7 days duration (3). There were no wound problems. The mean period of chest tube drainage was 3.3 +/- 3.0 days. Mean postoperative stay was 5.7 +/- 4.9 days. The pathologic diagnosis was benign disease in 28 patients (interstitial fibrosis/pneumonitis, 15; radiation fibrosis, 1; sclerosing hemangioma, 1; rheumatoid nodules, 1; granuloma, 2; nocardia, 1; infarct, 1; hamartoma, 4; scar, 1; cytomegalovirus pneumonia, 1), metastatic malignancy in 20 patients, and bronchogenic carcinoma in 13 patients. Five patients found at thoracoscopic pulmonary resection to have bronchogenic cancer had adequate pulmonary function and therefore underwent formal segmentectomy (3) or lobectomy (2). Thoracoscopic pulmonary resection was the only operation performed on patients with benign disease, patients with metastatic lesions, and selected patients with limited stage bronchogenic carcinoma at increased risk for thoracotomy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Transgenic mice overexpressing the phosphoenolpyruvate carboxykinase/bovine growth hormone (PEPCK/ bGH) hybrid gene and normal (nontransgenic) littermate controls (10 males + 10 females/group) were given access to tapwater and an ascending series of concentrations of ethanol (1.0–22.0%), then a similar ascending series of concentrations of nicotine (1.0–40.0 μg/ml), in a two-bottle choice test. Male transgenic mice consumed more and exhibited greater preferences for ethanol and nicotine than control males; transgenic females consumed less and showed lower preferences for ethanol, but not nicotine, than control females. These results suggest that chronic exposure to high levels of bGH may modulate the rewarding effects of ethanol and nicotine in mice in a gender-specific fashion.  相似文献   
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