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991.
992.
The in vitro activity of cefaclor, cephalothin and cefadroxil to 50 Escherichia coli, 23 Klebsiella pneumoniae and 20 Proteus mirabilis strains was tested with the disc diffusion and microdilution plate techniques. Cefaclor was more active than cefadroxil, while cephalothin was intermediate. The differences seriously affected the classification into the routine SIR system. For susceptibility testing we question the use of cephalothin as a class representative of oral cephalosporins.  相似文献   
993.
994.
The overall transplant experience at the Peter Bent Brigham Hospital which extends over twenty years has been reviewed; the course of all patients was updated to a followup of at least one year (through October 1973). A total of 388 patients received 427 renal isografts and allografts between March 1951 and October 1972. Of these, 58% were still alive at the end of the followup period, 50% with a functioning graft. The results of patient and allograft survival early (1959-1968) and later (1968-1973) in the experience have been compared. The significant decline in patient mortality, especially among recipients of cadaver allografts, demonstrates improved treatment of complications and increased availability of dialysis. The improvement of allograft function during the two time periods is less striking but still significant. Overall social and work rehabilitation following transplantation was evaluated in 284 patients, 86% of whom became at least as well adjusted as they had been prior to the development of renal failure. The incidence and individual causes for mortality and complications of transplantation have been compared to results from the National Dialysis Registry, figures comparable to those of the dialysis program at this institution. Transplantation and dialysis must be used conjointly and in a complimentary manner as part of the total treatment for those with end-stage renal failure.  相似文献   
995.
996.
Prostaglandin regulation of macrophage collagenase production.   总被引:17,自引:4,他引:13       下载免费PDF全文
The production of collagenase (EC 3.4.24.3) by endotoxin-stimulated macrophages was significantly inhibited by indomethacin, indicating that prostaglandins (PGs) mediate this effect. Inhibitions of collagenase production by indomethacin was overcome by addition of exogenous PGE2 at 10 nM whereas the addition of 0.1 and 1.0 micrometer PGE2 increased the enzyme production to 3 times that achieved by endotoxin. Although the addition of prostaglandin alone to macrophage cultures did not stimulate collagenase production, the simultaneous addition of PGE1 or PGE2 and endotoxin enhanced collagenase activity 2- to 10-fold. This increase was detectable at PGE concentrations of 10 nM and was optimal at 0.1-1.0 micrometer. PGF2alpha had little effect on either the enhancement of collagenase production by endotoxin-stimulated macrophages or its restoration in cultures inhibited by indomethacin. Radioimmunoassay of prostaglandins in the culture media revealed that macrophages exposed to endotoxin secreted 40-fold more PGE2 than did unstimulated cells. The increase in PGE2 was detected 4 hr after exposure to endotoxin and was maximal at 14 hr. The peak PGE2 concentrations in the culture media were similar to those of exogenous PGE2 (about 10 nM) needed to restore collagenase production in indomethacin-treated cultures. These findings demonstrate the involvement of PGE in the endotoxin-activation of macrophages with resultant production of collagenase.  相似文献   
997.
998.
Methodologic advances in the cytogenetic analysis of human solid tumors   总被引:3,自引:0,他引:3  
The major obstacle to successful cytogenetic analysis of human solid tumors is the acquisition of sufficient numbers of good quality metaphases for detailed cytogenetic analysis. At present, no single methodologic approach has been proven to provide successful chromosomal analysis of all human solid tumors. The technical aspects of cell culture, chromosome harvesting, and chromosome banding were the focus of considerable discussion during the First Workshop on Chromosomes in Solid Tumors. This report provides summaries of several technical protocols, emanating from several different laboratories, which have contributed to successful chromosome analysis of a variety of human solid tumors.  相似文献   
999.
The chromosomes of a cell line (NALM-1) derived from the leukocytes of a patient with chronic myelocytic leukemia (CML) were examined with several banding techniques. The modal chromosome number was 46 and the cells contained a Philadelphia chromosome (Ph1), due to the standard translocation of the missing segment of the long arm of chromosome No. 22 onto the distal end of the long arm of chromosome No. 9, i.e., t(9;22) (q34;q11). The Ph1-positive modal cells of the NALM-1 line also had two common marker chromosomes, an extra X-chromosome, and missing chromosomes in groups No. 7, 9, and 15. Immunologic examination of the NALM-1 cells revealed them to have non-T-non-B (null) surface characteristics. An antigen specific for cells of acute leukemia and a human la-like antigen were detected. These facts suggested that the NALM-1 cell line originated from CML cells and maintained the cytogenetic and Immunologic characteristics of such cells.  相似文献   
1000.
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