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11.
The effect of cetylpyridinium chloride (CPC) on pathogenic fungi and Nocardia asteroides was studied. Sputa seeded with each of 11 organisms (Aspergillus flavus; Aspergillus fumigatus, Blastomyces dermatitidis, Candida albicans, Coccidioides immitis, Cryptococcus neoformans, Geotrichum candidum, Histoplasma capsulatum; Nocardia asteroides, Paracoccidioides brasiliensis, and Sporothrix schenckii) were treated with CPC and kept for 2, 5 and 9 days. The CPC reagent used (0.5% CPC and 0.5% sodium chloride) is one the Mycobacteriolgoy Branch at the Center for Disease Control added to sputa before shipping them to laboratories for recovery of mycobacteria. None of the organisms tested survived this treatment, and none was recovered on mycological or mycobacteriological media. Seeded sputa containing these organisms were also tested with a second CPC reagent (0.02% CPC and 0.5% sodium chloride) and held for 2, 5 and 9 days. A few colonies of A. flavus, A. fumigatus, and N. asteroides were recovered from these samples. Neither the morphology of the fungi nor their stainability by the fluorescent antibody method was affected by treatment with the reagent containing 0.5% CPC. However, the background material in smears from the 0.5% CPC-treated samples retained the conjugate, and this made weakly fluorescing organisms more difficult to detect. The 0.5% CPC treatment did not alter the morphology of N. asteroides or its ability to be stained with Kinyoun acid-fast stain.  相似文献   
12.
Somatic, psychomotor, and intellectual development were studied in 11 patients who had total correction of congenital cardiac malformation in early infancy by the method of surface-induced deep hypothermia and circulatory arrest up to 43 minutes. Time between operation and re-evaluation ranged from 3 to 11 years (average 7 years). Somatic development was normal in all children. Psychomotor and intellectual behavior, measured by a battery of specially adapted test methods, failed to show a statistically significant difference when compared between the study group, a matched control group, and the normal population. Normal scores in psychomotor tests and normal intelligence quotients (I.Q.) were present in 8 patients; mental retardation was found in 2 patients: and unstable behavior, evident from different tests, was present in one. Except for the last case, in none of the patients was the method was found to be the primary cause of the abnormal behavior. Deep hypothermia and circulatory arrest in early infancy does not appear to have a negative influence on somatic, psychomotor, or intellectual development.  相似文献   
13.
After presenting the topographical and pathological basis for the habitual luxation of the shoulder joint, our experience with the Bankart-Müller operation on 38 of our own patients was described. The results are characterized as very good, particularly two years and longer after the operation.  相似文献   
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Eighteen male patients between the ages of 25 and 50 were given on a double blind randomized basis (A) 40 gms. galactose (B) 50 gms. arabinogalactan and 0.11 gm. sodium saccharin (C) 2 gm. methyl cellulose and 0.083 gm. sodium saccharin and (D) 4 gm. galactose, all in 200 ml water. Blood glucose, galactose and insulin levels were determined during a six hour period before and after ingestion. The three first mentioned solutions tasted equally sweet, the fourth was essentially tasteless. None of these feedings altered plasma insulin or glucose levels. It appears that in contrast to other conclusions reached by earlier investigators sweet taste is unable to induce insulin secretion through neurogenic pathways.  相似文献   
17.
The localization of soluble, cercarial antigen preparation (CAP) in cercariae and schistosomules of Schistosoma mansoni was performed at the light and electron microscope levels using the unlabeled antibody method. Reaction produce was observed associated with the contents of the pre- and postacetabular glands and with the filamentous coat of mature cercariae. No reaction product was observed associated with the glycoacalyx of schistosomules. However, several schistosomules did retain remnants of their filamentous coats and reaction product was observed associated with those remains. CAP components were also observed in the area surrounding the intrasporocyst cercariae.  相似文献   
18.
Drinking water is supplied by individual roof-catchment systems for homes and businesses near a dissolving sulfite pulp mill (now closed) located just north of Ketchikan in southeast Alaska. This study was conducted to determine if polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) found in the sediments of the roof-catchment cisterns resulted from historical deposition of stack emissions from the pulp mill's multi-fuel power boilers. Fly ash from the power boilers had maximum total PCDD/F concentrations of 3.08 x 10(5)-3.10 x 10(6) ng/kg, which resulted from combustion of bleach plant wastewater sludge and saltwater-soaked wood waste. Cistern sediments had maximum total PCDD/F concentrations of 7.71 x 10(4) ng/kg. Potential sources of PCDDs/Fs in the cistern sediments were considered to be automobile exhaust, heating oil combustion, and private trash burning as well as pulp mill boiler emissions. Discriminant analysis was used to analyze differences between profiles of tetra through octa homologue classes of PCDDs/ Fs (defined as proportional contributions to total concentration) from different source terms. Homologue profiles of potential sources from Ketchikan included in this analysis were fly ash collected from the mill's power boilers and soils collected from background areas (areas with similar PCDD/F sources as the residences [e.g., auto exhaust and burn barrels] near the mill but beyond the zone of aerial deposition of emissions from the mill). Profiles for emissions from automobile exhaust, fertilizers, oil heating, residential trash burning, and residential wood heating were also included in the source "training" data set (for the discriminant analysis) using data from published literature. The classification rules developed from the discriminant analysis were applied to the following test media sampled at Ketchikan: roof-catchment cistern sediments and soils collected from areas in the vicinity of the mill's power boilers (i.e., nearby residential or commercial [developed] areas, on the mill property, and nearby forestlands). The homologue profiles of cistern sediment and nearby developed area soil samples were similar to background soils, whereas the profiles for the forestland soil samples (influenced by emissions from the mill but not other anthropogenic sources) closely matched the fly ash pattern. The homologue profiles of the emission sources from published data were more similar to one another than either background soils or fly ash. Soil samples from the mill property were classified as members of all source groups. On the basis of these analyses, the composition of PCDDs/Fs detected in the cistern sediments is typical of Ketchikan background conditions and not reflective of mill emissions.  相似文献   
19.
To modulate the bioavailability and perhaps improve the tumor cell selectivity of O6-alkylguanine-DNA alkyltransferase (AGT) inactivators, pivaloyloxymethyl ester derivatives of O6-benzylguanine (BG) were synthesized and tested as AGT inactivators and as substrates for cellular esterases. The potential prodrugs examined were the 7- and 9-pivaloyloxymethyl derivatives of O6-benzylguanine (7- and 9-esterBG), and of 8-aza-O6-benzylguanine (8-aza-7-esterBG and 8-aza-9-esterBG) and the 9-pivaloyloxymethyl derivative of 8-bromo-O6-benzylguanine (8-bromo-9-esterBG). The benzylated purines were all potent inactivators of the pure AGT and of the AGT activity in HT29 cells and cell extracts. Each ester was at least 75 times less potent than the corresponding benzylated purine against the pure human AGT. In contrast, the activities of esters and their respective benzylated purine were similar in crude cell extracts and in intact cells. The increase in potency of esters in cellular extracts could be explained by a conversion of the respective prodrug to the more potent benzylated purine in the presence of cellular esterases. The apparent catalytic activity (Vmax/Km) of liver microsomal esterase for 8-azaBG ester prodrugs was 70-130 times greater than for BG prodrugs and 10-20 times greater than for 8-bromo-9-esterBG. Tumor cell hydrolysis of the esters varied considerably as a function of cell type and prodrug structure. These data suggest that these or related prodrugs may be advantageous for selective AGT inactivation in certain tumor types.  相似文献   
20.
We calculated the electrostatic force between a planar interface, such as a planar-supported lipid bilayer membrane, and the tip of a stylus on which another lipid bilayer or some other biomacromolecular system might be deposited. We considered styli with rounded tips as well as conical tips. To take into account the effect of dynamical hydrogen-bonded structures in the aqueous phase, we used a theory of nonlocal electrostatics. We used the Derjaguin approximation and identified the systems for which its use is valid. We pointed out where our approach differs from previous calculations and to what extent the latter are inadequate. We found that 1) the nonlocal interactions have significant effects over distances of 10-15 A from the polar zone and that, at the surface of this zone, the effect on the calculated force can be some orders of magnitude; 2) the lipid dipoles and charges are located a distance L from the hydrophobic layer in the aqueous medium and this can have consequences that may not be appreciated if it is ignored; 3) dipoles, located in the aqueous region, can give rise to forces even though the polar layer is unchanged, and if this is ignored the interpretation of force data can be erroneous if an attempt is made to rationalize an observed force with a knowledge of an uncharged surface; 4) the shape of the stylus tip can be very important, and a failure to take this into account can result in incorrect conclusions, a point made by other workers; and 5) when L is nonzero, the presence of charges and dipoles can yield a force that can be nonmonotonic as a function of ionic concentration.  相似文献   
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