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The yield of the phage QB is always less than the yield of the phage MS2, the conditions of cultivation being similar. This is due to the fact that the yield of the phage QB from an infection centre is lower by a factor of 5--10 than the yield of the phage MS2. The yield of the phages may be increased by optimizing conditions of cultivation. The RNA-containg phages MS2 and QB were cultivated in the peptone-yeast growth medium in fermenters with the working volume of 30 and 50 litres. The yields were 2--5-10(13) particles/ml and 1--4-10(12) particles/ml for the phages MS2 and QB, respectively. The specific infectiveness of purified phage preparations was 2--4-10(12) particles/OD260 (MS2) and 2--4-10(11) particles/OD260 (QB). 相似文献
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Patients with empyema and impaired immune response often remain in a toxic condition after tube thoracostomy because the infection is not localized and walled off satisfactorily. Consequently, the reported mortality rate is extremely high. Despite the expectation of a high mortality rate from thoracotomy and débridement in this category of critically ill patients, we were forced to perform pleural decortication in eight patients after lesser procedures had failed. They were immunodeficient because of (1) high-dose steroids (HDS) for sagittal sinus thrombosis, (2) HDS for systemic lupus erythematosus, (3) HDS for chronic myelogenous leukemia and myelofibrosis, (4) HDS for multiple myeloma, (5) hemolytic anemia with pulmonary infiltrates, (6) chemotherapy for Hodgkin's disease, (7) diabetes mellitus with Kimmelstiel-Wilson disease, and (8) diabetes mellitus with chronic glomerulonephritis. Six of the eight patients survived and were discharged with completely healed incisions 3 to 6 weeks after operation. This compares well with the survival rates reported by others. Although risky, the over-all survival rate may be better with thoracotomy and decortication than with prolonged tube drainage and open drainage in immunodeficient patients with empyema, and the period of morbidity is shortened considerably. 相似文献
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J Vredenburgh R Fishman D Coniglio L Matters M Elkordy M Ross A Hussein P Rubin C Gilbert W Petros WP Peters 《Canadian Metallurgical Quarterly》1998,21(6):543-547
We investigated tissue staining for Bcl-2 and Bax proteins, which regulate apoptosis, as indicators of chemotherapeutic effect in patients with gastric cancer. In 23 patients with gastric carcinoma biopsy specimens were obtained endoscopically prior to chemotherapy and stained immunohistochemically with anti-Bcl-2 and anti-Bax antibodies. Patients then were treated with continuous infusion of 5-FU and cisplatin. No correlation was seen between chemotherapeutic effect and Bcl-2 or Bax alone. However, among the Bax-positive cases, the patients with Bcl-2-positive tumors were significantly more chemoresistant (p = 0.036) and had worse prognoses (p = 0.008) than Bcl-2-negative cases. Therefore, immunohistochemical staining for Bcl-2 protein may predict chemotherapeutic efficacy or guide specific therapeutic choices in treating Bax-positive tumors. 相似文献
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