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991.
The influence of temperature and pH on growth of Leuconostoc mesenteroides subsp. mesenteroides FR52 and production of its two bacteriocins, mesenterocin 52A and mesenterocin 52B, was studied during batch fermentation. Temperature and pH had a strong influence on the production of the two bacteriocins which was stimulated by slow growth rates. The optimal temperature was 20 degrees C for production of mesenterocin 52A and 25 degrees C for mesenterocin 52B. Optimal pH values were 5.5 and 5.0 for production of mesenterocin 52A and mesenterocin 52B respectively. Thus, by changing the culture conditions, production of one bacteriocin can be favoured in relation to the other. The relationship between growth and specific production rates of the two bacteriocins, as a function of the culture conditions, showed different kinetics of production and the presence of several peaks in the specific production rates during growth. 相似文献
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995.
KK Van Rompay CJ Berardi S Dillard-Telm RP Tarara DR Canfield CR Valverde DC Montefiori KS Cole RC Montelaro CJ Miller ML Marthas 《Canadian Metallurgical Quarterly》1998,177(5):1247-1259
To determine if passively acquired antiviral antibodies modulate virus transmission and disease progression in human pediatric AIDS, the potential of pre- and postexposure passive immunization with hyperimmune serum to prevent oral simian immunodeficiency virus (SIV) infection or disease progression in newborn rhesus macaques was tested. Untreated neonates became infected after oral SIV inoculation and had high viremia, and most animals developed fatal AIDS within 3 months. In contrast, SIV hyperimmune serum given subcutaneously prior to oral SIV inoculation protected 6 newborns against infection. When this SIV hyperimmune serum was given to 3 newborns 3 weeks after oral SIV inoculation, viremia was not reduced, and all 3 infants died within 3 months of age due to AIDS and immune-complex disease. These results suggest that passively acquired antihuman immunodeficiency virus (HIV) IgG may decrease perinatal HIV transmission. However, anti-HIV IgG may not impart therapeutic benefit to infants with established HIV infection. 相似文献
996.
Sarcoidosis presenting solely as a granulomatous colitis is rare and appears identical to Crohn's disease. A 56-yr-old woman developed a Crohn's-like illness, which remitted after 5-ASA therapy. Two months later, she developed fever, adenopathy, muscle weakness, and peripheral neuropathy. A diagnosis of sarcoidosis was made after an extensive search for an infectious or rheumatological cause. This case illustrates the utility of serum angiotensin converting enzyme level in differentiating sarcoidosis from Crohn's disease. 相似文献
997.
H Berg J Roed J Viby-Mogensen CR Mortensen J Engbaek LT Skovgaard JJ Krintel 《Canadian Metallurgical Quarterly》1997,41(9):1095-1103
BACKGROUND: After anaesthesia involving pancuronium a high incidence of both residual neuromuscular block and postoperative pulmonary complications (POPC) has been reported. The aim of this study was to compare the incidence of POPC following the use of pancuronium, atracurium, and vecuronium, and to examine the effect of residual neuromuscular block on the incidence of POPC. METHODS: A total of 691 adult patients undergoing abdominal, gynaecological, or orthopaedic surgery under general anaesthesia were randomised to receive either pancuronium, atracurium, or vecuronium. Perioperatively, the response to train-of-four (TOF) nerve stimulation was evaluated manually. Postoperatively, the TOF ratios were measured mechanomyographically, and through a 6-day follow-up the patients were examined for pulmonary complications. RESULTS: The incidence of residual block, defined as a TOF ratio < 0.7, was significantly higher in the pancuronium group (59/226: 26%) than in the atracurium/vecuronium groups (24/450: 5.3%). In the pancuronium group, significantly more patients with residual block developed POPC (10/59: 16.9%) as compared to patients without residual block (8/167: 4.8%). In the atracurium/vecuronium groups, the incidence of POPC was not significantly different in patients with (1/24: 4.2%) or without (23/426: 5.4%) residual block. Multiple regression analysis indicated that abdominal surgery, age, long-lasting surgery, and a TOF ratio < 0.7 following the use of pancuronium were potential risk factors for the development of POPC. CONCLUSION: Postoperative residual block caused by pancuronium is a significant risk factor for development of POPC. 相似文献
998.
Turning brain into blood: a hematopoietic fate adopted by adult neural stem cells in vivo 总被引:1,自引:0,他引:1
CR Bjornson RL Rietze BA Reynolds MC Magli AL Vescovi 《Canadian Metallurgical Quarterly》1999,283(5401):534-537
Stem cells are found in various organs where they participate in tissue homeostasis by replacing differentiated cells lost to physiological turnover or injury. An investigation was performed to determine whether stem cells are restricted to produce specific cell types, namely, those from the tissue in which they reside. After transplantation into irradiated hosts, genetically labeled neural stem cells were found to produce a variety of blood cell types including myeloid and lymphoid cells as well as early hematopoietic cells. Thus, neural stem cells appear to have a wider differentiation potential than previously thought. 相似文献
999.
OPGL is a key regulator of osteoclastogenesis, lymphocyte development and lymph-node organogenesis 总被引:3,自引:0,他引:3
YY Kong H Yoshida I Sarosi HL Tan E Timms C Capparelli S Morony AJ Oliveira-dos-Santos G Van A Itie W Khoo A Wakeham CR Dunstan DL Lacey TW Mak WJ Boyle JM Penninger 《Canadian Metallurgical Quarterly》1999,397(6717):315-323
The tumour-necrosis-factor-family molecule osteoprotegerin ligand (OPGL; also known as TRANCE, RANKL and ODF) has been identified as a potential osteoclast differentiation factor and regulator of interactions between T cells and dendritic cells in vitro. Mice with a disrupted opgl gene show severe osteopetrosis and a defect in tooth eruption, and completely lack osteoclasts as a result of an inability of osteoblasts to support osteoclastogenesis. Although dendritic cells appear normal, opgl-deficient mice exhibit defects in early differentiation of T and B lymphocytes. Surprisingly, opgl-deficient mice lack all lymph nodes but have normal splenic structure and Peyer's patches. Thus OPGL is a new regulator of lymph-node organogenesis and lymphocyte development and is an essential osteoclast differentiation factor in vivo. 相似文献
1000.