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1.
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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Tolerance of ocular iontophoresis in healthy volunteers.   总被引:4,自引:0,他引:4  
To evaluate ocular tolerance, healthy volunteers were iontophoresed transclerally using novel OcuPhor trade mark hydrogel drug delivery applicators filled with balanced salt solution. In this three-period crossover study in 24 male and female subjects, 16 subjects received 0 mA and two of the following DC currents: 0.1, 0.5., 1.0, 2.0, 3.0, or 4.0 mA for 20 min; 6 subjects received 3 mA for 20 min and 1.5 mA for 40 min (both equivalent to 60 mAmin total charge). Safety and tolerance were determined by subjective VAS and objective ophthalmic assessments. Subjects were evaluated before and up to 22 hr after dosing. The applicators were well-tolerated and no clinically significant changes in symptomology or in ophthalmic assessments were seen following exposure to 0-3.0 mA for 20 min or 1.5 mA for 40 min. At 4.0 mA 2 of 4 subjects reported a burning sensation under the applicator during dosing which resolved by 22 hr post-dose; superficial changes in fluorescein staining were observed at 1 hr, but not at 22 hr. The OcuPhor trade mark system has promise for noninvasive drug delivery to the eye.  相似文献   
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Peripheral quantitative computed tomography (pQCT) has mainly been used as a research tool in children. To evaluate the clinical utility of pQCT and formulate recommendations for its use in children, the International Society of Clinical Densitometry (ISCD) convened a task force to review the literature and propose areas of consensus and future research. The types of pQCT technology available, the clinical application of pQCT for bone health assessment in children, the important elements to be included in a pQCT report, and quality control monitoring techniques were evaluated. The review revealed a lack of standardization of pQCT techniques, and a paucity of data regarding differences between pQCT manufacturers, models and software versions and their impact in pediatric assessment. Measurement sites varied across studies. Adequate reference data, a critical element for interpretation of pQCT results, were entirely lacking, although some comparative data on healthy children were available. The elements of the pQCT clinical report and quality control procedures are similar to those recommended for dual-energy X-ray absorptiometry. Future research is needed to establish evidence-based criteria for the selection of the measurement site, scan acquisition and analysis parameters, and outcome measures. Reference data that sufficiently characterize the normal range of variability in the population also need to be established.  相似文献   
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The effects of an externally applied direct-current electric field on the movement of cultured rabbit corneal epithelial cells and stromal fibroblasts were studied. After a latency of approximately 20 minutes in an electric field, both epithelial cells and stromal fibroblasts became spindle shaped and underwent galvanotropism by aligning their long axes perpendicular to the applied electric field. The electric field stimulus thresholds for galvanotropic movements in epithelial cells and stromal fibroblasts were 4V/cm and 6 V/cm, respectively. After an additional latency of 30 minutes, both cell types manifested galvanotaxic movements: epithelial cells commenced migration in the cathodal (downfield) direction and stromal fibroblasts in the anodal (upfield) direction. For both types of cells, ruffled membranes and lamellipodia were abundant at the leading edges of migrating cells and cell processes underwent retraction at the trailing edges. At field strengths of above 10 V/cm, evidence of cellular damage (manifested by cellular rounding and detachment), attributable to the electric field treatment, was observed after 4 hours. These preliminary results suggest that galvanotaxic responses could be exploited clinically in the enhancement of corneal wound healing.  相似文献   
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The effects of atropine sulfate (ATS) and atropine methyl nitrate (ATM) on the conditional discrimination behavior of rats were investigated in eight-hour experimental sessions. Responding of rats was reinforced on either a lighted or a darkened lever depending on whether lights over both levers had been on during the preceding sample portion of the trial. Zero-delay and four-second-delay trials were randomly interspersed. Quality of performance was analyzed using the A' sensitivity measure of signal detection theory. Both drugs reduced both sensitivity and the percentage of trials on which responding occurred (percent response) below saline treatment levels. The two drugs did not reliably differ from each other in their effects on sensitivity during the zero-delay condition, but reliable differences between the two drugs emerged during the four-second-delay condition at doses above 0.8 mg/kg. Percent response recovered more rapidly for animals treated with ATS than responding occurred (percent response) below saline treatment levels. The two drugs did not reliably differ from each other in their effects on sensitivity during the zero-delay condition, but reliable differences between the two drugs emerged during the four-second-delay condition at doses above 0.8 mg/kg.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The effect of age on binding of MK-801 in the cat visual cortex.   总被引:3,自引:0,他引:3  
We have examined the effect of age on the binding of (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5,10-imine maleate (MK-801) in the cat visual cortex. We hypothesized that this binding might change with age because: (1) MK-801 binds to a site associated with the N-methyl-D-aspartate (NMDA) receptor; (2) the NMDA receptor complex has been implicated in neural plasticity; (3) plasticity in the cat visual cortex is age dependent. We used standard receptor binding techniques to measure MK-801 binding in membrane homogenates in cats aged 7 days (d), 21 d, 43 d, 83 d, 7-8 months (mo) and over 2 years. Glutamate (100 microM), glycine (30 microM) and spermidine (20 microM) were used to enhance binding. We found that MK-801 binding is maximal at about 6 weeks of age, decreases slightly by 83 days and then decreases more dramatically in adults. Saturation analysis showed that the of binding with age resulted from variation in number of binding sites and not from variation in affinity. The ability of Mg2+ to inhibit MK-801 binding did not change with age. Dark rearing did not alter the development of MK-801 binding sites.  相似文献   
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Learning and memory function in men with untreated blood pressure elevation   总被引:3,自引:0,他引:3  
Learning and memory processes were compared in 20 men with untreated blood pressure elevation and 20 normotensive control subjects matched for age, education, and average alcohol consumption. Subjects were identified from a larger sample of 469 factory workers who had participated in an epidemiologic investigation. Three measures (e.g., Symbol-Digit Learning Test [Ryan & Butters, 1980] and Visual Reproductions-Immediate and Delayed Recall [Wechsler, 1945] ) from a previously administered test battery were chosen for comparison on the basis of statistical power calculations. Results indicate that relative to normotensive control subjects, men with elevated blood pressure performed more poorly on all three tests. These results are independent of other known influences on neuropsychological performance and are likely a consequence of elevated blood pressure.  相似文献   
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