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61.

Background

Implementation of WHO case management guidelines for serious common childhood illnesses remains a challenge in hospitals in low-income countries. The impact of locally adapted clinical practice guidelines (CPGs) on the quality-of-care of patients in tertiary hospitals has rarely been evaluated.

Methods and Findings

We conducted, in Kenyatta National Hospital, an uncontrolled before and after study with an attempt to explore intervention dose-effect relationships, as CPGs were disseminated and training was progressively implemented. The emergency triage, assessment and treatment plus admission care (ETAT+) training and locally adapted CPGs targeted common, serious childhood illnesses. We compared performance in the pre-intervention (2005) and post-intervention periods (2009) using quality indicators for three diseases: pneumonia, dehydration and severe malnutrition. The indicators spanned four domains in the continuum of care namely assessment, classification, treatment, and follow-up care in the initial 48 hours of admission. In the pre-intervention period patients'' care was largely inconsistent with the guidelines, with nine of the 15 key indicators having performance of below 10%. The intervention produced a marked improvement in guideline adherence with an absolute effect size of over 20% observed in seven of the 15 key indicators; three of which had an effect size of over 50%. However, for all the five indicators that required sustained team effort performance continued to be poor, at less than 10%, in the post-intervention period. Data from the five-year period (2005–09) suggest some dose dependency though the adoption rate of the best-practices varied across diseases and over time.

Conclusion

Active dissemination of locally adapted clinical guidelines for common serious childhood illnesses can achieve a significant impact on documented clinical practices, particularly for tasks that rely on competence of individual clinicians. However, more attention must be given to broader implementation strategies that also target institutional and organisational aspects of service delivery to further enhance quality-of-care.  相似文献   
62.
Detriments to post-bleaching recovery of corals   总被引:6,自引:0,他引:6  
Predicting the response of coral reefs to large-scale mortality induced by climate change will depend greatly on the factors that influence recovery after bleaching events. We experimentally transplanted hard corals from a shallow reef with highly variable seawater temperature (23–36°C) to three unfished marine parks and three fished reefs with variable coral predator abundance and benthic cover. The transplanted corals were fragmented colonies collected from a reef that was relatively undisturbed by the 1997–1998 warm-water temperature anomaly, one of the most extreme thermal events of the past century, and it was assumed that they would represent corals likely to succeed in the future temperature environment. We examined the effects of four taxa, two fragment sizes, an acclimation period, benthic cover components, predators and tourists on the survival of the coral fragments. We found the lowest survival of transplants occurred in the unfished marine parks and this could be attributed to predation and not tourist damage. The density of small coral recruits approximately 6 months after the spawning season was generally moderate (~40–60/m2), and not different on fished and unfished reefs. Coral recovery between 1998 and 2002 was variable (0–25%), low (mean of 6.5%), and not different between fished and unfished reefs. There was high variability in coral mortality among the three unfished areas despite low variation in estimates of predator biomass, with the highest predation occurring in the Malindi MNP, a site with high coralline algal cover. Stepwise multiple regression analysis with 14 variables of coral predators and substratum showed that coralline algae was positively, and turf algae negatively associated with mortality of the transplants, with all other variables being statistically insignificant. This suggests that alternate food resources and predator choices are more important than predator biomass in determining coral survival. Nonetheless, large predatory fish in areas dominated by coralline algae may considerably retard recovery of eurythermal corals. This will not necessarily retard total hard coral recovery, as other more predator-tolerant taxa can recover. Based on the results, global climate change will not necessarily favor eurythermal over stenothermal coral taxa in remote or unfished reefs, where predation is a major cause of coral mortality.  相似文献   
63.

Background

Schistosoma mansoni exists in a complex environmental milieu that may select for significant evolutionary changes in this species. In Kenya, the sympatric distribution of S. mansoni with S. rodhaini potentially influences the epidemiology, ecology, and evolutionary biology of both species, because they infect the same species of snail and mammalian hosts and are capable of hybridization.

Methodology/Principal Findings

Over a 2-year period, using a molecular epidemiological approach, we examined spatial and temporal distributions, and the overlap of these schistosomes within snails, in natural settings in Kenya. Both species had spatially and temporally patchy distributions, although S. mansoni was eight times more common than S. rodhaini. Both species were overdispersed within snails, and most snails (85.2% for S. mansoni and 91.7% for S. rodhaini) only harbored one schistosome genotype. Over time, half of snails infected with multiple genotypes showed a replacement pattern in which an initially dominant genotype was less represented in later replicates. The other half showed a consistent pattern over time; however, the ratio of each genotype was skewed. Profiles of circadian emergence of cercariae revealed that S. rodhaini emerges throughout the 24-hour cycle, with peak emergence before sunrise and sometimes immediately after sunset, which differs from previous reports of a single nocturnal peak immediately after sunset. Peak emergence for S. mansoni cercariae occurred as light became most intense and overlapped temporally with S. rodhaini. Comparison of schistosome communities within snails against a null model indicated that the community was structured and that coinfections were more common than expected by chance. In mixed infections, cercarial emergence over 24 hours remained similar to single species infections, again with S. rodhaini and S. mansoni cercarial emergence profiles overlapping substantially.

Conclusions/Significance

The data from this study indicate a lack of obvious spatial or temporal isolating mechanisms to prevent hybridization, raising the intriguing question of how the two species retain their separate identities.  相似文献   
64.
Objective: Environmental conditions during early life may affect individual vulnerability to both physiological changes as well as psychiatric conditions, especially in those with a genetic susceptibility. Among all factors, sunlight exposure intensity has a crucial effect on affecting circadian functions high-risk individuals. A potential explanation of this relation is that excessive sunlight exposure is able to impair biological mechanisms, possibly through the dysregulation of serotonin and/or melatonin production/metabolism. The aim of this study was to evaluate the influence of excessive sunlight exposure in a sample of emergency psychiatry inpatients. Methods: All subjects were consecutively recruited from the Psychiatric Inpatient Unit of San Luigi Gonzaga Hospital, Orbassano (University of Turin, Italy) from September 2013 to August 2015. Socio-demographic and clinical characteristics were carefully collected. Results: We initially screened a sample of 900 patients; however, only 730 subjects voluntary accepted to participate in the study. Patients with admissions in spring/summer (a period in which daylight/darkness ratio is longer) showed a higher prevalence of involuntary admission, an earlier age at illness onset, a longer duration of hospitalization and admission for (hypo)manic episode. Conclusions: Excessive sunlight exposure may exert a fundamental role on psychopathological conditions presumably affecting biological vulnerability. A better understanding of its effect on the course of bipolar and other psychiatric disorders may assist in tailoring the adequate treatment for patients resulting in a shorter stay within hospitalized settings and a better treatment response.  相似文献   
65.
66.
The structure of the axillary organ of a batrachoidid species, the gulf toadfish (Opsanus beta Goode and Bean 1879), has been examined and several simple experiments designed to elucidate its function performed. Electron microscopy (EM) studies revealed cells and structures suggesting secretory and iono regulatory roles (e.g., abundant intracytoplasmic secretory particles, rough endoplasmic reticulum, sparse Golgi bodies, indented epithelial cells with microvilli, numerous endocytotic vesicles, etc.). Our physiological experiments allowed us to reach several conclusions: the organs do not excrete significant quantities of urea relative to other areas of the fish (head and gills), the organs do not secrete a substance that is toxic to a teleost test fish (Gambusia affinis), the secretions do not induce short-term modifications in locomotory activity of other gulf toadfish (e.g., by pheromonal means) and the secretions do not inhibit the growth of several species of microorganisms in culture. The function of the organ and its secretions remains unknown, representing a fertile area for research on structure and function in comparative physiology.  相似文献   
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69.
Godfrey Maina 《BBA》1974,333(3):481-486
1. Reserpine, like the uncoupling agent, 2,4-dinitrophenol prevents oxidative phosphorylation but stimulates the rate at which oxygen is reduced.

2. Both reserpine and 2,4-dinitrophenol fail to stimulate oxygen uptake by isolated mitochondria in the presence of arginine.

3. Both 2,4-dinitrophenol and reserpine induce proton permeability in the mitochondrial membrane so that H+ is absorbed from the suspending medium.

4. When the reaction system contains reserpine, accumulation of Ca2+ by mitochondria is inhibited.

5. Reserpine decreases both ADP:O and P:O ratios which strongly suggest that reserpine is an uncoupling agent.  相似文献   

70.
Summary The lung of the African lungfish (Protopterus aethiopicus) is paired, long and cylindrical. It is situated on the dorsal aspect of the coelomic cavity ventral to the ribs. Much of the gas exchange tissue is found in the proximal aspect of the lung with the caudal part largely taken up by a centrally situated air-duct with a few large peripherally located alveoli. Interalveolar septa, arranged at differing hierarchical levels from the air-duct, subdivide the lung into alveoli, the gas exchange compartments. The alveolar surface is covered by some cells characterized by microvilli on their free surface, while others are devoid of such structures. The general organization of the lung of Protopterus aethiopicus is similar to that of the other genera of Dipnoi, Neoceratodus and Lepidosiren, with the interalveolar septa increasing the surface area for gas exchange through pulmonary compartmentation. The abundant septal smooth muscle fibres and elastic tissue may contribute to the physiomechanical compliance of the lung. The undifferentiated alveolar pneumocytes and the double capillary system, observed in Protopterus, in general appear to characterize the very primitive lungs of the lower air-breathing vertebrates.  相似文献   
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