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1.
Several molecules, such as growth factors and neurotrophic factors, are required both for the differentiation of specific retinal cell types and the long-term cell survival of all retinal neurons. As diffusible factors, these molecules act non-cell-autonomously. Here, we describe the loss of function phenotype for dazed (dzd), a gene that acts cell-autonomously for retinal cell survival and affects the differentiation of rod photoreceptors and the Muller glia. By 3 days after fertilization, dazed mutant embryos have small eyes and slight heart edema. Acridine orange staining indicated a significant degree of retinal cell death occurring by 48 hr after fertilization, and histological analysis revealed that dying cells were found in the inner and outer nuclear layers and near the marginal zones. Although molecular and morphological differentiation of the inner retina and cone photoreceptors occurred, rod photoreceptors failed to differentiate beyond a small patch in the ventral retina and rod precursors failed to respond to exogenously added retinoic acid, which normally potentiated rod differentiation. Mosaic analysis indicated that the dazed gene acts cell-autonomously for rod production and cell survival, as dazed clones failed to produce rods outside the ventral patch and dazed cells were not maintained in wild-type hosts. Raising mutants under constant light resulted in severe retinal degeneration, whereas raising embryos under constant darkness did not provide any additional protection from cell death. Behavioral analysis showed that a subpopulation of adult fish that were heterozygous for the dazed mutation had elevated visual thresholds and were night blind, suggesting that dazed may also be required for long-term dim-light vision. Taken together, our studies suggest a role for the dazed gene in rod and Muller cell development and overall retinal cell survival and maintenance.  相似文献   
2.
BackgroundOrgan transplantation is considered one of the greatest advances of modern science, and it has given many patients a renewed lease on life. The demand for organs far exceeds the supply. Health professionals are fundamental in the process of organ procurement.ObjectiveTo assess the attitude, willingness, and associated factors in organ donation among health professionals of Gondar, Ethiopia.MethodsOur cross-sectional study was conducted among 382 randomly selected health professionals in Gondar using a self-administered questionnaire. Multivariable logistic regression analysis was applied to analyze the data.ResultsAmong health professionals, 79.1% had favorable attitude toward organ donation and 74.6% were willing to donate their organs. After adjusting for covariates, the odds of having a favorable attitude about organ donation were 3.2 and 11.9 times higher in the professions of laboratory technologists and medical doctors, respectively. By keeping all other variables constant, attitude was found to be positively associated with awareness (adjusted odds ratio [aOR] 12.74, 95% confidence interval [CI] 3.71-43.8) and being a member of the Red Cross Association (aOR 5.24, 95% CI 1.46-18.96). Willingness was positively associated with awareness (aOR 6.25, 95% CI 2.0-19.53), a member of the Red Cross Association (aOR 5.09, 95% CI 1.5-17.22), a laboratory technologist (aOR 3.57, 95% CI 1.37-9.29), and a medical doctor (aOR 6.52, 95 % CI 1.93-22.01).ConclusionsThe main findings indicated that the majority of health professionals in Gondar had a favorable attitude toward organ donation and were willing to donate their organs in times of need.  相似文献   
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Erqou S  Kebede Y  Mulu A 《Tropical doctor》2008,38(2):110-112
Beta lactam antibiotics were very effective against Streptococcus pneumoniae. However, resistance to this class of antibiotics has become an increasing problem. Reports of penicillin resistant and multidrug resistant strains are being made in many parts of the world. We examined the drug sensitivity pattern of S. pneumoniae isolates in a retrospective analysis of laboratory records of S. pneumoniae isolates between March 2001 and April 2005 at Gondar University Hospital, Ethiopia. A significant proportion of the isolates were found to be resistant to one or more of the commonly used antibiotics. Furthermore, the isolates appear to be acquiring an increasing resistance to crystalline penicillin, cotrimoxazole and ampicillin. This situation needs immediate attention.  相似文献   
5.
Febrile illnesses remain a major cause of morbidity and mortality in resource-poor countries, but too often, tests are not available to determine the causes, leading to misdiagnosis and inappropriate treatment. To determine the cause of febrile illnesses, we recovered the malaria smears from 102 children presenting with fever to Soddo Christian Hospital in Wolaitta Soddo, Ethiopia. DNA was isolated from the smears and evaluated by real-time polymerase chain reaction. We identified pathogen DNA with probes for Plasmodium spp., Streptococcus pneumoniae, Rickettsia spp., Salmonella spp., and Borrelia spp. Overall, we showed that it is possible to isolate high-quality DNA and identify treatable pathogens from malaria blood smears. Furthermore, our data showed that bacterial pathogens (especially Pneumococcus, Rickettsia spp., and Borrelia spp.) are common and frequently unrecognized but treatable causes of febrile illnesses in Ethiopian children.  相似文献   
6.

BACKGROUND

Hispanics in the United States represent diverse racial, ethnic, and socioeconomic groups, and manifest heterogeneous cardiovascular risks including diabetes. It is not known if there are residual differences in the control of diabetes among Hispanic groups given uniform access to diabetes care.

OBJECTIVE

To evaluate glucose control differences among Mexicans, Puerto Ricans, and Dominicans receiving substantial diabetes care and support in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial.

DESIGN

Secondary analysis of data from a randomized trial comparing two treatment strategies: intensive, targeting glycated hemoglobin below 6.0?%, and standard, targeting glycated hemoglobin between 7.0?% and 7.9?%.

PARTICIPANTS

Seven hundred and sixteen Hispanic and 6066 non-Hispanic white participants were recruited from 77 clinical sites across the United States and Canada. There were 243 Mexicans, 199 Puerto Ricans, and 150 Dominicans; and 135 of these Hispanic groups were born in the United States.

MAIN MEASURE

Glycated hemoglobin

RESULTS

Compared to Puerto Ricans, Mexicans were more likely (HR?=?1.38, CI:0.90?C2.10) and Dominicans as likely (HR?=?1.01, CI:0.66?C1.54) to achieve glycated hemoglobin goal in the intensive arm. Participants born in the United States achieved glycated hemoglobin goal at a higher rate than those born elsewhere (HR?=?1.57, CI:0.99?C2.51 in the intensive arm, HR?=?1.51, CI:0.95?C2.43 in the standard arm). These differences were not statistically significant. In the intensive arm, Puerto Ricans (OR?=?0.47, CI:0.31?C0.71), and Dominicans (OR?=?0.41, CI:0.26?C0.66) were less likely than non-Hispanic whites to achieve glycated hemoglobin goal, whereas the difference between non-Hispanic whites and Mexicans was not statistically significant, (OR?=?0.66, CI:0.43?C1.02).

CONCLUSIONS

Hispanic groups, given access to comprehensive diabetes care, differed from each other non-significantly and had a variable divergence from non-Hispanic whites in achieving intensive glycated hemoglobin goal. These differences, if confirmed, could be due to such factors as variable acculturation and functional health literacy levels that were not measured in the ACCORD trial, but should be further explored in future studies.  相似文献   
7.

Introduction and hypothesis

The aim of this study was to gain in-depth knowledge of women suffering from urinary incontinence (UI) in rural and semiurban settings in Ethiopia.

Methods

A qualitative study based on semistructured in-depth interviews with 26 informants, 18 of whom were women experiencing the symptom of urinary leakage. The study was conducted in the Amhara Region of northwest Ethiopia and was part of the Dabat Incontinence and Prolapse (DABINCOP) study.

Results

Limited access to water, soap, pads, and spare clothes characterized daily management of the symptom. The consequences for marital relationships and social life were of great concern to the informants. Shame, embarrassment, and fear of being discriminated against led to huge efforts to hide the leakage. Among informants who were not able to hide it, humiliating comments and discriminatory behavior were commonly experienced, sometimes leading to divorce and self-isolation. Women who disclosed their symptom usually had a person who supported them. Women with UI regarded it as unnatural and uncommon. Most took no action to improve the situation, as they saw no options for help.

Conclusions

Several circumstances limited the opportunities available to women to keep themselves clean, disclose the problem to others, and access health information and health-care facilities. In order to understand how women in this setting practically handled, perceived, and experienced living with UI, it was essential to address contextualized and sociocultural dimensions related to the symptom.  相似文献   
8.
BackgroundNeck pain is a common health problem throughout the world causing significant individual disability and economic burden on health care facility. Many factors are mentioned as a cause or association in relation to neck pain, of which degenerative and posttraumatic cause are the main ones. The aim of this study is to assess cervical spine Magnetic Resonance Imaging (MRI) patterns in patients presented with neck pain.MethodsA retrospective analysis of 160 patients who had cervical spine Magnetic Resonance Imaging (MRI) for evaluation of a neck pain was done. The study was conducted between February to August 2018 at Tikur Anbessa Specialized Hospital. The patients'' clinical history and magnetic resonance imaging reports were reviewed from their medical records. All patients who have cervical spine Magnetic Resonance Imaging (MRI) for a neck pain were included in the study. Those patients with acute traumatic neck pain were excluded.ResultsFrom a total of 160 patients, 71(44.4%) were males and 89(55.6%) were females. Degenerative cervical spine findings such as intervertebral disc degenerations were seen in 127(79.4%) patients. Non-degenerative imaging findings such as neoplasm and infection were seen in 10(6.3%) patients only. The MRI was normal in 23(14.4%) of them.ConclusionThe most common cause of neck pain from this study is degenerative changes of the cervical spine, which was predominant in the older age groups. Non-degenerative causes such as neoplasm and infection were less common findings.  相似文献   
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10.
In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal technique in the presence of l-cysteine. l-Cysteine can serve as a greener source of sulfur as well as a capping agent to help the growth of MoS2 nanosheets. The prepared materials were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), electron transmission microscopy (TEM), X-ray photoelectron microscopy (XPS), and Brunauer, Emmett, and Teller (BET) analysis. The results showed that MoS2 NSs are of high crystallinity with a lattice spacing of 0.61 nm. The optical bandgap of MoS2 NSs nanosheets prepared using l-cysteine as a source of sulfur was found to be 1.79 eV. The photocatalytic degradation of MoS2 NSs towards methylene orange (MO) and rhodamine blue (RB) dyes under sunlight was found to be promising for practical applications. The fast kinetics of degradation of MO and RhB was observed over a wide range of pH range. Moreover, MoS2 NSs showed excellent antifungal activities against Trichophyton mentagrophytes and Penicillium chrysogenum fungus.

In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal technique in the presence of l-cysteine.  相似文献   
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