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21.
Vascular dementia (VaD) accounts for about 20% of all dementias, and vascular risk is a key factor in more than 40% of people with Alzheimer's disease (AD). Little is known about inflammatory processes in the brains of these individuals. We have examined inflammatory mediators (interleukin (IL)-1beta, IL-1alpha, IL-6 and tumour necrosis factor alpha) and chemokines (macrophage inflammatory protein 1, monocyte chemo-attractant protein (MCP)-1 and granulocyte macrophage colony-stimulating factor) in brain homogenates from grey and white matter of the frontal cortex (Brodmann area 9) from patients with VaD (n = 11), those with concurrent VaD and AD (mixed dementia; n = 8) and from age-matched controls (n = 13) using ELISA assays. We found a dramatic reduction of MCP-1 levels in the grey matter in VaD and mixed dementia in comparison to controls (55 and 66%, respectively). IL-6 decreases were also observed in the grey matter of VaD and mixed dementia (72 and 71%, respectively), with a more modest decrease (30%) in the white matter of patients with VaD or mixed dementia. In the first study to examine the status of inflammatory mediators in a brain region severely affected by white-matter lesions, our findings highlight - in contrast to previous reports in AD - that patients at the later stage of VaD or mixed dementia have a significantly attenuated neuro-inflammatory response.  相似文献   
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OBJECTIVE: to determine the prevalence and type of intestinal parasites in HIV infected and uninfected patients with diarrhea. DESIGN: A cross-sectional study was conducted at Gondar University hospital, Northwest Ethiopia, between March 2003 and October 2004. PATIENTS AND METHODS: A total 312 consecutive diarrheic patients were included in the study. Stool specimens were collected and examined for intestinal parasites following direct, formol-ether concentration and modified acid fast staining methods. RESULTS: Among the patients, 63.8% were found to be HIV seropositive. The prevalence of intestinal parasites in HIV seropositive and seronegative diarrheic patients was 30.6% and 33.6%, respectively. The most prevalent parasites were Strongyoides stercoralis (9.0%) and Entamoeba histolytica (8.3%) followed by Ascaris lumbricoides (5.4%) and Cryptosporidium species (5. 1%). CONCLUSION AND RECOMMENDATION: The prevalence of intestinal parasites in diarrheic patients was very high. Institution of appropriate intervention measures are needed to reduce morbidity in such patients.  相似文献   
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BACKGROUND: Urinary tract infection (UTI) is one of the most common bacterial infections encountered by clinicians in developing countries. Although UTI seldom leads to complications, it can cause significant morbidity and mortality. OBJECTIVE: To identify the etiologic agents of UTIs and to assess their antimicrobial susceptibility pattern. METHODS: A retrospective analysis of 1420 mid-stream urine specimens processed fobr culture and antimicrobial susceptibility testing in the bacteriology laboratory of Gondar University Teaching Hospital between September 2002 and August 2003 was conducted RESULTS: Significant bacteriuria (cultures with > 10(5) colony forming units of bacteria per ml of urine) was observed in 399 (28.1%) of the specimens. Two bacteria each were isolated from 14 specimens, making the number of bacteria isolated to be 413 with the isolation rate of 29.1%. The most commonly isolated bacteria were Escherichia coli 166 (40.2%), Staphylococcus aureus 60 (14.5%), Klebisella species 42 (10.2%) and Citrobacter species 34 (8.2%). Among Gram-positive organisms S. aureus showed high level qf drug resistance for tetracycline 48 (80%), corimoxazole 32 (53.3%), chloramphenicol 32 (53.3%), amnpicillin 26 (43.3%) and penicillin 22 (36.7%). Of the Gram-negative bacteria, extremely high resistance patterns were found in Salmonella species for ampicillin 5 (100%), erythromycin 5 (100%), penicillin 5 (100%), co-trimoxazole 3 (60%), tetracycline 3 (60%) and 3 chloramphenicol (60%). Multiple drug resistance was observed in 85.7% of the isolates. Only 5.1% of the isolates were found to be sensitive to all antibiotics tested. CONCLUSION: Resistance to the commonly used antibiotics was found to be very high among the isolates leaving clinicians with very few choices of drugs or the treatment of UTIs. It is therefore, critical that the use of antimicrobial agents with in a hospital and all other responsible institutions he reviewed  相似文献   
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The distribution and colocalization of nitric oxide synthase (NOS) and reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase was studied in the neuronal elements of the adrenal gland of the rat. Ganglion cells and many nerve fibres in the gland showed both NOS-immunoreactivity and NADPH-diaphorase staining. The adrenal cortical cells showed NADPH-diaphorase staining but were not immunoreactive for NOS. Positive labelling for both NADPH-diaphorase and NOS was found in bundles and in single fibres with varicosities, preferentially located around the noradrenaline (NA)-storing cells. Adrenaline (A)-storing cells and ganglion cells in the medulla, along with the cortical cells and blood vessels in the zona glomerulosa, received relatively fewer positive fibres.  相似文献   
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Background

Lack of basic infrastructure, poor knowledge of hygiene and practices in food service establishments can contribute to outbreaks of foodborne illnesses. The aims of this study were to investigate the food safety knowledge and practices of food handlers and to assess the sanitary conditions of food service establishments in Bahir Dar town.

Methods

A cross-sectional study was conducted in Bahir Dar in May 2011 and data were collected using questionnaire and observation checklist on employees'' knowledge of food hygiene and their practices as well on sanitary conditions of the food service establishments

Results

The median age of the food handlers was 22 years and among the 455 subjects 99 (21.8%) have had food hygiene training. Sixty six percent of the establishments had flush toilets whereas 5.9% of the establishment had no toilet. Only 149 (33.6%) of the establishments had a proper solid waste collection receptacle and there was statistically significant association between the sanitary conditions and license status of the establishments (p=0.01). Most of all, knowledge gap in food hygiene and handling practice was observed. In addition, there was statistically significant difference between trained (professional) handlers and non-trained handlers with regard to food hygiene practices (p<0.05). While more than 50% of the handlers prepare meals ahead of the peak selling time, more than 50% of the left over was poorly managed.

Conclusion

This study revealed poor sanitary conditions and poor food hygiene practices of handlers. Educational programs targeted at improving the attitude of food handlers and licensing and regular inspections have been recommended.  相似文献   
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In the modern era, radial artery graft is being used with increasing frequency to replace saphenous vein as a conduit for coronary artery bypass surgery. Several reports have shown encouraging early results of radial grafts compared to saphenous grafts. Despite these advantages, radial artery graft failure requiring revascularization does occur. We report on the clinical, angiographic, and technical characteristics and the follow-up results of 22 patients who underwent percutaneous intervention of radial grafts.  相似文献   
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