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991.
There is evidence that leukocyte contaminating red blood cells and platelet concentrates are responsible for refractoriness to platelet transfusions. The efficacy of a cotton-wool filter to remove leukocytes from red blood cells has been documented previously. The present study was designed to evaluate whether the cotton-wool filters can effectively remove leukocytes from platelet concentrates. Sixty pools of random-donor platelets and single-donor plateletpheresis products were filtered through a cotton-wool filter. The efficacy of filtration was determined by measuring the absolute numbers of leukocytes and platelets and subpopulations of mononuclear cells. The average platelet loss was 8% per pool of random platelets and 10% per plateletpheresis product. The average leukocyte removal was 99% from a pool of random platelets and plateletpheresis concentrates collected by CS-3000 and 90% from plateletpheresis concentrates harvested by single-stage COBE/IBM-2997. The filtration removed 100% of granulocytes, 95% of monocytes, 90% of B-lymphocytes, and 85% of T-lymphocytes. We conclude that filtration through a cotton-wool filter is an efficient and cost-effective method for preparation of leukocyte-poor platelets. 相似文献
992.
993.
Direct modulation by androgens of the response of human bone cells (SaOS-2) to human parathyroid hormone (PTH) and PTH-related protein 总被引:3,自引:0,他引:3
We have reported previously that 17 beta-estradiol (E2) inhibits selectively the cAMP response to human (h) PTH and PTH-related protein (hPTHrP), but not to vasoactive intestinal peptide, in human osteoblast-like cells (SaOS-2). We have now extended these studies to investigate the actions of androgens on hPTH-stimulated accumulation of cAMP, and on the roles of new protein synthesis and pertussis toxin (PTox) substrates in the actions of steroid hormones on SaOS-2 cells. Pretreatment with testosterone (T) or 5 alpha-dihydrotestosterone (5 alpha-DHT) for 4-12 h at concentrations of 10(-12) to 10(-8) M inhibited significantly the cAMP response to hPTH by up to 50-70% of control. Like E2, the actions of T and 5 alpha-DHT were selective for hPTH or hPTHrP; there was no inhibition of the stimulatory action of vasoactive intestinal peptide. Two related steroids, 5 beta-DHT and 17 alpha-epitestosterone, did not inhibit the action of hPTH. Pretreatment of cells with cycloheximide, under conditions which inhibited protein synthesis by greater than 90%, reduced the cAMP response to hPTH but did not block the further inhibitory actions of E2, T, or 5 alpha-DHT. Pretreamtent of cells with PTox (100 ng/ml) for 24 h, enhanced the accumulation of cAMP stimulated by hPTH consistent with an action of PTox on Gi; however, the inhibitory actions of E2, T, and 5 alpha-DHT on PTH-stimulated cAMP accumulation were not attenuated by PTox. We conclude that androgens, as well as estrogens, act directly on human bone cells to modulate selectively an early effect of hPTH. The inhibitory actions of these steroid hormones do not appear to depend on new protein synthesis and may not involve a functionally active PTox substrate, presumably Gi. 相似文献
994.
Lidocaine increases the energy required for ventricular defibrillation in dogs. Because sodium channel-blocking agents that are weak bases have pH-dependent electrophysiologic effects, we investigated the pH dependence of lidocaine (pKa, 7.9) on internal defibrillation energy requirements in 28 dogs with atrial spring and left ventricular patch electrodes. Results of defibrillation testing were used to derive 50% and 90% successful energy requirements (ED50 and ED90) using logistic regression and were compared with analysis of variance. Acidosis produced by hydrochloric acid infusion decreased the arterial pH from 7.40 +/- 0.05 (SD) to 7.18 +/- 0.03 (n = 8, p less than 0.01), but no significant change in ED90 was observed (14 +/- 4 to 16 +/- 6 J). Lidocaine infusion to therapeutic levels (4.2 +/- .07 micrograms/ml) at normal pH (7.42 +/- 0.02) increased ED90 from 13 +/- 3 to 17 +/- 3 J (n = 6, p less than 0.05), and subsequent acidosis (pH 7.19 +/- 0.02, p less than 0.01) exacerbated this effect of lidocaine on ED90 (22 +/- 5 J, p less than 0.05). Alkalosis produced by respirator hyperventilation increased the arterial pH from 7.41 +/- 0.03 to 7.60 +/- 0.03 (n = 8, p less than 0.01), with a fall in ED90 from 13 +/- 4 to 8 +/- 3 J (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
995.
S G Gundersen A Bjoerneklett J N Bruun 《Scandinavian journal of infectious diseases》1989,21(2):225-228
A 41-year-old woman had acute hepatitis A infection complicated with severe anemia due to selective erythroblastopenia and hemolysis. A mechanism involving a cellular immune reaction is suggested. The hematological complications resolved during steroid treatment. She later developed a transient seropositive arthritis. 相似文献
996.
The use of pelvic ultrasonography in the evaluation of adolescents with pelvic inflammatory disease 总被引:2,自引:0,他引:2
N Golden H Cohen G Gennari S Neuhoff 《American journal of diseases of children (1960)》1987,141(11):1235-1238
To evaluate the use of pelvic ultrasonography in the diagnosis and management of female adolescents with pelvic inflammatory disease (PID), sonograms of 60 patients with PID were compared with those of 40 age-matched controls. Sonograms were evaluated for adnexal volume, adnexal adherence, uterine size, and the presence of cul-de-sac fluid. Eleven (19.3%) of the 57 patients with PID, in whom adequate sonograms were obtained, had tubo-ovarian abscesses; in seven of these patients, the abscesses were diagnosed ultrasonographically before suspected clinically. Even in those patients without tubo-ovarian abscesses, the mean (+/- SD) adnexal volume in the PID group was significantly larger than that of the control group (11.0 +/- 6.8 cm3 vs 5.2 +/- 2.7 cm,3 respectively). Adnexal adherence, uterine size, and the presence of cul-de-sac fluid were not useful in differentiating patients with PID from normal controls. Pelvic ultrasonography can be a useful adjunct in the diagnosis and management of PID in adolescents and may, in some instances, provide diagnoses in the absence of clinical findings. 相似文献
997.
John P Elliott Hugh S Miller Suzanne Coleman Debbie Rhea Diana Abril Karen Hallbauer Niki B Istwan Gary J Stanziano 《Journal of perinatology》2005,25(10):626-630
OBJECTIVE: To assess the impact of activity restriction (AR) on the incidence of preterm birth in women treated for preterm labor testing negative for fetal fibronectin (fFN). STUDY DESIGN: Women who were diagnosed with preterm labor and tocolyzed with magnesium sulfate were concurrently screened with fFN for the purpose of subsequent management. Included were consenting patients with negative fFN, gestational age 23 0/7-33 6/7 weeks, cervical dilation < or =3 cm, and minimal vaginal bleeding. Patients were randomized to AR or no AR. Primary study outcome was incidence of preterm delivery and interval from randomization to delivery. RESULTS: A total of 73 women with negative fFN were randomized (36 with AR, 37 without AR). The overall preterm birth rate was 40%, with 44.4% of patients with AR and 35.1% of patients without AR delivering preterm, p=0.478. CONCLUSION: Maternal AR did not impact pregnancy outcome. The incidence of preterm birth in symptomatic women testing fFN negative was higher than previously reported. 相似文献
998.
Bone and joint sepsis 总被引:1,自引:0,他引:1
999.
E. Wieczerzak E. Jankowska S. Rodziewicz‐Motowido A. Giedo J. giewka Z. Grzonka M. Abrahamson A. Grubb D. Brmme 《Chemical biology & drug design》2005,66(Z1):1-11
Abstract: We have designed and synthesized a new series of azapeptides which act as potential inhibitors of cathepsin B and/or cathepsin K. Their structures are based upon the inhibitory sites of natural cysteine protease inhibitors, cystatins. For the synthesized azapeptides, the equilibrium constants for dissociation of inhibitor–enzyme complex, Ki, were determined. Comparison of these values indicated that all of the azainhibitors act much stronger toward cathepsin B. Z‐Arg‐Leu‐His‐Agly‐Ile‐Val‐OMe ( 7 ) proved to be approximately 500 times more potent for cathepsin B than for cathepsin K. To be able to explain the obtained experimental values we used the molecular dynamics procedures to analyze the interactions between cathepsin B and compound 7 . We also determined the structure of the most potent and selective cathepsin B azainhibitor by means of NMR studies and theoretical calculations. In this report, we describe SAR studies of azapeptide inhibitors indicating the influence of the conformational flexibility of the examined compounds on inhibition of cathepsins B and K. 相似文献
1000.
G K Zherlov S V Kozlov N S Rudaia T G Zherlova 《Experimental & clinical gastroenterology》2006,(3):44-50, 71
The article presents an original method of laparoscopic anti-reflux surgery, immediate and long-term results of the treatment of 132 patients with esophageal opening hernia. It also describes the analysis of the life quality of patients with the gastroesophageal reflux disease before and after the surgery. 相似文献