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Diarrhea occurs commonly in African human immunodeficiency virus (HIV) infections. A case-control (HIV-positive vs. -negative) study of adults with diarrhea was done in Lusaka, Zambia, to determine the prevalence of intestinal infection by HEp-2 cell-adherent Escherichia coli. Adherent E. coli were more common in HIV-positive patients with acute diarrhea than among HIV-negative controls (60% vs. 33%) and were found significantly more often in HIV-positive patients with chronic diarrhea than among HIV-negative controls with chronic diarrhea (79% vs. 17%, P < .002). Adherent strains were found significantly more often among HIV-positive patients (69%) than in 22 asymptomatic subjects (36%, P < .02). The HEp-2 cell adherence of the E. coli strains did not show a common pattern. Adherent bacteria were also observed in colonic biopsies from 32% of Zambians with chronic diarrhea who underwent endoscopy. Adherent E. coli may be an important cause of HIV-associated diarrhea in Zambia.  相似文献   
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Observations on the uptake of tyramine by hepatocytes indicate that the amine is taken up by simple diffusion and a transporter mediated system, with a Km of 39 microM and a Vmax of 270 pmol/min/10(5) cells. The carrier-mediated process is pH- and temperature-dependent and requires an activation energy of 12.9 kcal/mol. An overshoot uptake is achieved a few minutes after adding this amine to the cell suspension, suggesting that active transport is involved. This is supported by the finding that partial inhibition of the uptake can be induced by oligomycin, azide, cyanide and dinitrophenol. NO3-, SCN- and SO4(2-), which change the membrane potential significantly, and depress the transporter mediated uptake further, suggesting that the membrane potential is the driving force for the entry of this amine across hepatic membrane. Cysteine is essential for the normal carrier function; whereas, histidine, tryptophan, arginine and lysine do not directly deal with the activity of the carrier. Many substances, but not amino acids, H, M, and N receptor agonists, can inhibit the uptake of tyramine. It is possible that other amines can enter hepatocytes by using this transporter.  相似文献   
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Halving the malnutrition of under five of years has been set as one of the goals to be achieved by the year of 2000 by Chinese government. So it is important to know the present status of child malnutrition and its trend of changing, in order to predict the possible outcome of the achievement of the goal. According to the Child Survey carried out by the State Statistic Bureau (SSB) in 26 provinces and autonomous regions and 3 municipalities in 1992, the prevalence of malnutrition of under five was: moderate and severe underweight, stunting and wasting were 17.9%, 34.7% and 4.7% respectively. But there are significant differences among urban and rural children and between different provinces. The highest prevalence rate usually occurred in the second year of life of the children, and this may be the result of inadequate weaning food provided to the children. As compared with the data collected in 1987 by SSB in 9 provinces and autonomous regions, an impressive improvement in underweight has occurred within these 5 years. The average declined prevalence was 20.5%. It is specially true for urban children. To stunting, there was also improvement for urban children but not in the rural, resulting and over all increasing of prevalence by 5.9%. To wasting, the prevalence for urban children was low and remained at the same level while there was some what increase in the rural. So, according to these results, with constant economic development and more attempt made in areas and groups at risk, the goal to decrease malnutrition in half in terms of underweight could be reached by the year of 2000.  相似文献   
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An examination of 30 patients against the background of using both the operative and conservative methods of treatment was performed in order to study the rheological properties of blood and selection of the most informative tests for diagnosis of microcirculatory disturbances in diseases of the gastrointestinal tract and gastroduodenal area. The authors propose methods of investigation of deformability and viscosity of erythrocytes in patients with the surgical diseases in question. The methods are simple, quite handy for any surgical hospital and polyclinic laboratories. In addition to being used in investigations of the aggregative ability of erythrocytes and viscosity of the whole blood, these methods can be of use in express diagnosis of rheological disorders. The endogenous intoxication in patients with the diseases in question was found to be accompanied by deep rheological disturbances. The deformability of erythrocytes and their viscosity index which can pass ahead of the shifts in other parameters characterizing the hemocoagulative and rheological properties of blood are changed. A conclusion is drawn that the parameters of the erythrocyte deformability and viscosity can be an additional criteria of the adequacy of therapy used for patients with the diseases in question.  相似文献   
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We performed the first double-blind, crossover comparison between levodopa/carbidopa (LD/CD) in optimized liquid versus tablet doses to measure plasma LD levels and relative effects on disabilities (motor function, fluctuations, and dyskinesias) in patients with Parkinson's disease. Twenty-three subjects with motor fluctuations were optimized with open-label LD/CD tablets and liquid. In a double-dummy design, patients randomly received 2 weeks of liquid and 2 weeks of tablet LD/CD. Twice during each arm, we evaluated patients hourly 9 AM to 4 PM with the use of plasma LD levels, the Unified Parkinson's Disease Rating Scale, a dyskinesia rating scale, and "on-off" ratings. Patients receiving liquid LD/CD ingested significantly higher doses and had significantly improved motor function and total "on" time, without an increase in dyskinesia severity. The number of motor fluctuations in the two phases was not significantly different. LD levels and variability were also equivalent with the two formulations. At optimized dosing, liquid LD/CD offers a means to significantly improve motor disability in patients with Parkinson's disease without exacerbating dyskinesia.  相似文献   
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