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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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To evaluate the correlation between persistent symptoms while stents are in place and final outcome in children with nasolacrimal duct obstruction (NLDO). A retrospective observational case series, with medical record review that included indications for surgery, surgical procedure, presence of symptoms while stents were in place, and final outcome after stent removal. Twenty-eight children with NLDO had nasolacrimal duct stents placed in 42 eyes. Twenty-one of the 42 eyes (50%) had minimal or no signs or symptoms of NLDO while stents were in place, and 18 of 21 (86%) were symptom-free after stent removal. Twenty-one of the 42 eyes (50%) remained symptomatic while stents were in place. Eleven of these 21 eyes (52%) had good outcomes after stent removal. Ten (48%) of these patients had persistent symptoms after stent removal requiring further treatment. The prognosis for a good outcome is excellent if symptoms of NLDO resolve while stents are in place. The prognosis is poorer if symptoms of NLDO persist, but more than half of such patients still have good outcomes. Careful counseling of parents regarding these outcomes should be performed before considering additional interventions.  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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