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Lactobacillus curvatus, isolated from a spoiled vacuum-packaged 'pariza' type meat product, was used to inoculate modified MRS broth containing sodium lactate, sodium acetate and potassium sorbate in different concentrations, alone or in inter se combinations. Two commercial preparations (MIX 1 and MIX 2) were also used containing combinations of the above antimicrobials. Results from the preservatives addition to the culture medium showed highest antimicrobial activity in the case of the sodium lactate (2%, 3% or 4%), sodium acetate (0.5%) and potassium sorbate (0.15%) combination. Results from the preservatives addition to two types of thermally processed meats showed that sodium lactate and the combination of sodium lactate, sodium acetate and potassium sorbate were the most effective; extending the products shelf life an additional 10 days. Finally, MIX 1 and MIX 2 suppressed the lactic acid bacteria (LAB) growth in the culture medium but not in the final product. 相似文献
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The advent of new technology has led to a proliferation of studies examining the functional roles of discrete prefrontal cortical areas. This has created a need for more precise information regarding the morphological characteristics of this region. Existing architectonic maps of human and monkey brains are not compatible with regard to areal delineations and topography, creating significant difficulty in interpreting comparative data. Therefore, we have re-examined the comparative morphological organization of the prefrontal cortex in humans and rhesus monkeys. Our analysis indicates that the architectonic areas in both species correspond in terms of morphological features as well as topographical locations. We have developed a common organizational schema for these areas, thereby allowing for a resolution of previous discrepancies. Moreover, in monkeys a connectional analysis has revealed that each of the newly designated areas is characterized by a unique pattern of cortical relationships. The present organizational schema provides a framework for interrelating findings such as those obtained from human brain imaging studies with those from behavioural investigations of non-human primates. 相似文献
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I Bahner K Kearns S Coutinho EH Leonard DB Kohn 《Canadian Metallurgical Quarterly》1997,90(5):1787-1798
Patients with human immunodeficiency virus-1 (HIV-1) infection often present with bone marrow (BM) failure that may affect all hematopoietic lineages. It is presently unclear whether this failure reflects a direct viral impairment of the CD34+ hematopoietic progenitor cells or whether the virus affects the BM microenvironment. To study the effects of HIV-1 on the BM microenvironment, we examined the stromal cell monolayers in long-term BM culture (LTBMC), which are the in vitro equivalent of the hematopoietic microenvironment. We assessed the hematopoietic support function (HSF) of human stromal layers by determining the cellular proliferation and colony-forming ability of hematopoietic progenitors from BM cells grown on the stromal layers. We show that the HSF is reduced by in vitro infection of the human stromal cell layer by a monocytotropic isolate of HIV-1 (JR-FL). There is no loss of HSF when the stromal cell layer is resistant to HIV-1 replication, either using murine stromal cell layers that are innately resistant to HIV-1 infection or using human stromal cells genetically modified to express a gene that inhibits HIV-1 replication (an RRE decoy). Decreased HSF was seen using either human or murine hematopoietic cells, if the stromal cells were human cells that were susceptible to HIV-1 infection. These in vitro studies implicate HIV-1 replication in the stroma as the essential component causing decreased hematopoietic cell production in HIV-1 infection. 相似文献
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A sample of 42 case notes of alcoholic patients were abstracted for 17 items by three different raters. Interrater agreement was generally rather low. Research based on case-note abstraction which does not report on abstraction reliabilities must therefore be viewed with some suspicion. It would be helpful if clinical material could more often be collected in a standardized manner. 相似文献
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JJ Ellestad-Sayed RA Nelson MA Adson WM Palmer EH Soule 《Canadian Metallurgical Quarterly》1976,29(12):1333-1338
To investigate further an apparent relationship between chronic ulcerative and granulomatous colitis and pantothenic acid deficiency, colonic tissues obtained at the time of colectomy in 29 patients with these disorders were assayed for pantothenic acid and for coenzyme A (CoA) activity. For comparison, normal colonic tissues free of pathological lesions were obtained from 31 patients having colectomy for carcinoma or diverticulitis. Plasma, red blood cells, and colonic mucosa were assayed microbiologically for free and total pantothenic acid. The activity of CoA in colonic mucosa was determined by assaying the acetylation of sulfanilamide. Concentrations of free, bound, and total pantothenic acid in blood and in colonic mucosa did not differ between the two groups of patients. Bound pantothenic acid increased linearly with total pantothenic acid. Colonic mucosa concentrated free pantothenic acid to about 50 times the level of blood, and pantothenic acid in red cells was similar to the concentration in plasma. Compared to normal gut mucosa, CoA activity was markedly low in mucosa from patients with chronic ulcerative or granulomatous disease despite the presence of normal amounts of free and bound pantothenic acid. A block in the conversion of bound pantothenic acid to CoA in diseased mucosa is suggested. 相似文献
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