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The effect of cephalothin prophylaxis on postoperative ventriculoperitoneal shunt infections. 总被引:1,自引:0,他引:1
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M J Rieder T C Frewen R F Del Maestro A Coyle S Lovell 《Canadian Medical Association journal》1987,136(9):935-938
Postoperative infection is an important complication after insertion of a ventriculoperitoneal (VP) shunt in children with hydrocephalus. A randomized double-blind placebo-controlled study was performed to determine the efficacy of cephalothin in preventing postoperative shunt infection. Sixty-three children who presented for elective VP shunt insertion between January 1982 and December 1985 and who did not have a history of shunt infections were randomly assigned to receive four doses of prophylactic cephalothin, 25 mg/kg (32 patients), or of a multivitamin placebo (31 patients). Postoperative infection developed in 6% of the treatment group, compared with 10% of the placebo group, a difference that was not statistically significant, although a clinical significance may have been masked by the small sample size. A large multicentre trial is needed to determine the efficacy of antibiotic prophylaxis in reducing the incidence of postoperative VP shunt infections. 相似文献
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Release of soluble transferrin receptor from the surface of human leukemic HL60 cells 总被引:2,自引:0,他引:2
Information regarding transferrin (Tf) receptor degradation is largely incomplete. HL60 cells were shown to release to their growth medium a Tf-binding protein which could be immunoprecipitated by anti-Tf receptor monoclonal antibodies (MoAbs) B3/25 and OKT9. Soluble Tf receptor was detected in the medium within one hour of replating of cells, and its release was inhibited at 4 degrees C. The affinity of Tf for the soluble receptor released by cells (kd = 2.3 x 10(-10) mol/L) was slightly lower than its affinity for the detergent-solubilized cellular receptor (kd = 1.2 x 10(-10) mol/L). 125I-Tf internalized and released by cells subsequently bound to Tf receptor released by the same cells, and soluble Tf receptor in the conditioned medium (CM) inhibited 125I-Tf binding to intact cells. The soluble Tf receptor isolated from the CM was smaller (78,000 daltons) than the cell surface receptor (94,000 daltons) when analyzed by gel electrophoresis under reducing conditions. Isolated cell membranes readily released soluble receptor; however, this release could be blocked by protease inhibitors. The soluble Tf receptor may represent the extracytoplasmic domain of the cellular Tf receptor released from the surface of HL60 cells through proteolytic cleavage by a membrane-based protease. 相似文献
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B Betschart H P Rieder K Gautschi D de Savigny A A Degrémont M Tanner 《Acta tropica》1987,44(2):191-211
Total protein concentration, zinc, prealbumin, albumin, alpha-1-, alpha-2-, beta- and gammaglobulin concentrations were measured in serum samples collected in three successive years (1982, 1983 and 1984) from children (1 month-15 years) of Kikwawila village, Tanzania. The analysis of a total of 1590 serum samples provided the baseline data for children living in a rural Tanzanian community. The total protein values and the concentrations of betaglobulin were within the range described for Caucasians. Albumin, prealbumin, alpha-1- and alpha-2-globulin concentrations were below these standard values. On the other hand the gammaglobulin concentration was twice as high. The concentrations of total protein, gammaglobulin and prealbumin correlated with age. From 1982 to 1983 a significant decrease of most of the serum components (incl. zinc) was observed, although in children older than 2 years the alpha-1-globulins increased. All values increased again from 1983 to 1984, except for the zinc concentration, which decreased further. The individual fluctuations were analysed by comparing paired values for the children participating in the period 1982-1983, or 1983-1984. The proportion of children showing large fluctuations, sometimes exceeding the selected limits of tolerance, was larger in the period 1982-1983 than 1983-1984. This was consistent with the overall pattern found for all children. The prealbumin level, which has been postulated to be an indicator for malnutrition or borderline malnutrition, was analysed in detail. The values were far below normal values (200-300 mg/l), reaching a plateau with 130 mg/l among 4-6-year-old children. The individual fluctuations indicated a decrease from 1982 to 1983, which was considerable both in terms of the proportion of children showing a decrease (55%) and in the magnitude of the decrease. There was an increase from 1983 to 1984 but this increase did not compensate for the loss in 1983. Prealbumin concentrations showed a slight trend towards decreased values with stunting and wasting. No direct correlation was found between the other biochemical parameters and the parasite or anthropometric data collected at the same time. It was difficult to establish direct relationships between the biochemical parameters, which mainly indicate the health status of the child at the time-point of the survey, and anthropometric parameters which reflect the history of the individual over a long period. No direct correlation could be established between the biochemical parameters and the parasitological data.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318