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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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Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
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Oxygen free radicals generated during the reperfusion of an ischemic organ may cause further cellular injury; removal of these oxygen radicals by scavengers protects tissue from reperfusion injury. Thus, oxygen radical scavengers could protect kidneys after warm ischemia and long hypothermic perfusion. Porcine kidneys were incubated at 37 degrees C for 45 minutes, placed on a pulsatile perfusion apparatus at 7 degrees C for 48 hours, and then autografted to iliac vessels. Superoxide dismutase (10 mg) and catalase (10 mg) in 10 mL of phosphate-buffered saline solution were infused into the renal artery during a three-minute interval before reperfusion. The kidneys treated with the superoxide dismutase-catalase solution had significantly improved function compared with controls receiving only phosphate-buffered saline solution. The mean (+/- SEM) serum creatinine level on postoperative day 5 was 510 +/- 100 mumol/L (5.75 +/- 1.12 mg/dL) (n = 12) vs the control value of 840 +/- 90 mumol/L (9.54 +/- 1.01 mg/dL) (n = 11). There was more extensive cellular damage in the control kidneys. This demonstrates the efficacy of oxygen radical scavengers in protecting pig kidneys after warm ischemia and prolonged preservation.  相似文献   
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Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury.  相似文献   
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Elevations of epidermal growth factor (EGF) and Ca2+ concentrations in the wound site are associated with reepithelialization during wound healing. In addition, Ca2+ and EGF can both induce increases in matrix metalloproteinase‐9 (MMP‐9) synthesis. However, little is known about the interplay of these events in regulating the migration properties of primary keratinocytes on collagen I, the most abundant extracellular matrix component in the skin. We found that EGF stimulated both chemokinetic and chemotactic migration of primary keratinocytes on collagen I; however, MMP‐9 was required for EGF‐stimulated chemotaxis but not EGF‐stimulated chemokinesis. Calcium at 0.5 mM stimulated chemokinetic migration of keratinocytes. Together, Ca2+ and EGF stimulated higher levels of chemokinesis than either stimulus alone. Furthermore, Ca2+ could restore the ability of keratinocytes from MMP‐9 null mice to undergo EGF‐stimulated chemotaxis. The phosphatidylinositol‐3 kinase inhibitor LY294002 inhibited both EGF‐ and Ca2+‐stimulated chemokinetic migration. In contrast, the MEK inhibitor PD98059 blocked Ca2+‐ but not EGF‐stimulated chemokinetic migration of keratinocytes. A combination of PD98059 and LY294002 was required to inhibit Ca2+ enhancement of EGF‐stimulated migration completely. Calcium‐stimulated chemokinesis was completely blocked by either the protein kinase C‐α inhibitor Gö6976 or the src/fyn inhibitor PP2. Using primary keratinocytes, our results showed how the combined action of Ca2+, EGF, and MMP‐9 regulated the contributions of extracellular‐regulated kinase and phosphatidylinositol‐3 kinase toward chemokinetic and chemotactic migration of keratinocytes.  相似文献   
9.
Taking advantage of two large, population-based, and longitudinal datasets collected after the 1999 floods in Mexico (n = 561) and the September 11, 2001 terrorist attacks in New York (n = 1267), we examined the notion that resilience may be best understood and measured as one member of a set of trajectories that may follow exposure to trauma or severe stress. We hypothesized that resistance, resilience, recovery, relapsing/remitting, delayed dysfunction, and chronic dysfunction trajectories were all possible in the aftermath of major disasters. Semi-parametric group-based modeling yielded the strongest evidence for resistance (no or mild and stable symptoms), resilience (initially moderate or severe symptoms followed by a sharp decrease), recovery (initially moderate or severe symptoms followed by a gradual decrease), and chronic dysfunction (moderate or severe and stable symptoms), as these trajectories were prevalent in both samples. Neither Mexico nor New York showed a relapsing/remitting trajectory, and only New York showed a delayed dysfunction trajectory. Understanding patterns of psychological distress over time may present opportunities for interventions that aim to increase resilience, and decrease more adverse trajectories, after mass traumatic events.  相似文献   
10.
Circumferential choledochoplasties with vascular grafts have rarely been attempted either experimentally or in clinical practice. In this study, choledochoplasties using autologous venous and arterial grafts were performed in rats. Sixty-four rats were randomly selected into five treatment groups: A) venous interpositional graft replacement of a choledochus gap without a stent; B) venous graft with prolene stent; C) venous graft with polyethylene stent; D) arterial graft; E) a control group with simple resection between ligatures in the choledochus. The operative mortality in treatment groups B, C, D, and E, was 0, and 13% in group A. At 12 weeks follow-up, all the rats in group E had died, whereas, 52.2% (P <.05) of the rats in group A, 30% of the rats in group B, 57% of the rats in group C, and 92.8% of the rats in group D survived treatment. Surviving animals were sacrificed at 3 months for further examination. The morphology and caliber of the common bile duct of these rats were normal in 25% of the rats in group A, 33% of the rats in group B, 25% of the rats in group C, and 84.6% of the rats in group D. Proximal dilations were found in the rats presenting with abnormal morphology. The dilations were less marked in the group treated by arterial choledochoplasties. Laboratory and clinical cholestatic parameters were within normal ranges in the presence of common bile duct dilations less than four times the normal duct caliber. Electron microscopic examination of the venous and arterial graft at 3 months follow-up revealed a fibrous ring composed of collagen fibers, fibroblasts, and remnants of elastic fibers. Regenerated ductal epithelium encompassed both types of grafts. Epithelialization was more pronounced in venous grafts as compared to arterial grafts. Biliary epithelium was able to colonize the venous grafts and resume cell specialization and function as in normal biliary epithelium. The most satisfactory results were obtained using venous grafts with stents or by using arterial grafts. © 1993 Wiley-Liss Inc.  相似文献   
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