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41.
This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures.  相似文献   
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In this paper a new method for cleaning of filter media is presented, and the cleanability with different textures and surface finishes is compared. With the method described, it is possible to evaluate the quality of the cleaning process. According to the German VDMA standard cleaning test, riboflavin and malt extract are applied as model contaminants for evaluation of the cleaning results. To compare the cleanability of filter media with different properties and geometries the results are adapted to the law of mass transfer and to the Sherwood number, a dimensionless parameter describing the quality of a cleaning process.  相似文献   
44.
Filter cake washing is a purification method for particulate products in liquids. This process is mostly one step of a sequence in a solid–liquid separation process. For soluble products not only the mechanical transport mechanisms in washing but also the dissolution process of the product must be considered in order to describe the washing process appropriately. An unconsidered dissolution may cause problems and often severe product loss depending on the material properties. This paper presents several methods of soluble solids washing including filter cake washing by pressure and centrifugal forces as well as moving bed washing. The advantages and drawbacks of each method are discussed to evaluate the suitability of its technical application.  相似文献   
45.
A novel UV-C irradiation device in laboratory scale was tested for its potential to inactivate bacteria in naturally cloudy apple juice. In this device, liquid flows through a helically wound tubing wrapped around a quartz glass tube containing a 9 W UV lamp with an irradiation intensity of 60 W/m2 at 254 nm. The equipment was capable of reducing numbers of inoculated Escherichia coli and Lactobacillus brevis from an initial concentration of approximately 106 CFU/ml or 104 CFU/ml to below detectable limits in commercial naturally cloudy apple juice at a flow rate of 2 l/h, and to well below 1 × 102 also at higher flow rates of 4 and 8 l/h. Numbers of Saccharomyces cerevisiae could be reduced from an initial level of ca. 1 × 104–1 × 102 CFU/ml or less at flow rates of 2 and 4 l/h. Although E. coli could be effectively inactivated also in self-extracted, as well as industrially processed apple juice, contaminating yeast and lactic acid bacteria were not completely eliminated.  相似文献   
46.
The two temperature-sensitive (ts) lesions present in influenza A/Hong Kong/68-ts-1[E] (H3N2 68) virus were transferred via genetic reassortment to influenza A/Georgia/74 (H3N2 74) wild-type virus. A recombinant clone possessing both ts lesions and the shutoff temperature of 38 C of the Hong Kong/68 ts donor and the two surface antigens of the Georgia/74 wild-type virus was administered to 32 seronegative adult volunteers. Thirty-one volunteers were infected, of whom only five experienced mild afebrile upper respiratory tract illness. The wild-type recipient virus was a cloned population that induced illness in five of six infected volunteers. Therfore, the attenuation exhibited by the Georgia/74-ts-1[E] virus could reasonably be assumed to be due to the acquisition of the two ts-1[E] lesions by the Georgia/74 wild-type virus. The serum and nasal wash antibody responses of the ts-1[E] vaccinees were equivalent to those of the volunteers who received wild-type virus. The two ts lesions present in the Hong Kong/68-ts-1[E] virus have now been transferred three times to a wild-type virus bearing a new hemagglutinin, and in each instance the new ts recombination exhibited a similar, satisfactory level of attenuation and antigenicity for adults. It seems likely that the transfer of the ts-1[E] lesions to any new influenza virus will regularly result in attenuation of a recombinat virus possessing the new surface antigens.  相似文献   
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The effects of chronic tolbutamide treatment were examined in a diabetic animal model in which abnormal myocardial function and composition have previously been demonstrated. Eight diabetic dogs were given tolbutamide 250 mg/day orally and compared with seven untreated diabetics, five healthy dogs receiving tolbutamide, and eight normal controls. After one year, resting hemodynamic studies in the intact anesthetized state showed that treated diabetic dogs had a significantly higher left ventricular end-diastolic pressure of 12.1+/-1.3 mm Hg associated with normal end-diastolic volume, compared to 6.1+/-0.8 mm Hg in untreated diabetics (P less than 0.01) and 6.3+/-0.5 in normals. Stroke work and ejection fraction were similar to normals. Acute volume expansion revealed a larger rise of left ventricular end-diastolic pressure in treated and untreated diabetics than normals, without a significant stroke volume response in treated diabetics. Enhanced stiffness of myocardium appeared to be related to interstitial accumulation of periodic acid-Schiff staining material, further intensified in treated diabetics by triglyceride accumulation observed on electron microscopy and by chemical analysis. Thus treatment of diabetes with tolbutamide, despite improved glucose tolerance, effected further reduction of left ventricular function and altered morphology of myocardium.  相似文献   
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Under conditions of experimental myocardium infarction caused in dogs by ligation of the anterior descending branch of the left coronary artery, the activity of alpha-ketoglutarate dehydrogenase and succinate dehydrogenase in mitochondria of the cortex, cerebellum and medulla ablongata lowers most intensively on the first and fifth day after the appearance of acute myocardium infarction. Activation of the most important enzymes of the pentose-phosphate cycle (glucose-6-phosphate dehydrogenase and transketolase) which is clearly pronounced on the fifth day is observed in the mentioned sections. In the authors' opinions the above changes in the activity of the enzymes are due to the brain hypoxia which may be the main reason of disturbance in the function of the central nervous system under this disease.  相似文献   
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