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31.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse.  相似文献   
32.
A case of invasive Fusarium keratitis in a previously healthy male patient was treated successfully with cornea transplantation and systemic and topical voriconazole after treatment failure with topical amphotericin B and systemic itraconazole. Topical voriconazole was well tolerated, and, in conjunction with the oral administration, it resulted in a high level of the drug in the anterior chamber of the eye (which was 160% of the plasma drug level).  相似文献   
33.
We studied the effects of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSFrh) on the internal pH of granulocytes using the fluorescent probe BCECF. GM-CSFrh did not directly alter the resting pH of granulocytes isolated from the peripheral blood; however, when the cells were preincubated for 90 minutes with the growth factor and then activated with the chemotactic peptide N-formyl met leu phe (fMLP), they exhibited both an acceleration in the initial rate of acidification and a marked delay in realkalinization. The kinetic changes both in initial acidification and in subsequent realkalinization induced by GM-CSFrh priming were not prevented by protein synthesis inhibitors and were observed in granulocytes harvested from patients with both sex-linked and autosomal recessive chronic granulomatous disease (CGD). By directly quantitating H+ ion secretion, by monitoring the effects of sodium repletion on intracellular pH, and through use of the sodium channel inhibitors amiloride and dimethyl amiloride and the Na+/K+-ATPase inhibitor ouabain, we showed that the altered kinetics of intracellular acidification and alkalinization following fMLP stimulation of GM-CSFrh- primed granulocytes could not be accounted for by changes in transmembrane proton exportation regulated by the Na+/H+ antiport channel. Although the initial acidification following fMLP was abrogated by 2-deoxy-D-glucose in both GM-CSFrh-pretreated and GM-CSFrh- untreated granulocytes, retardation of the subsequent phase of alkalinization was observed in GM-CSFrh-primed cells even after inhibition of both glycolytic and mitochondrial metabolism. Our data indicate that the increased cytosolic acidification following fMLP stimulation in granulocytes "primed" with GM-CSFrh does not result from disordered proton excretion but instead from increased release of intracellular free acid which is only partially coupled to glucose catabolism or to the generation of superoxide anion (O2-).  相似文献   
34.
Biologic basis for interleukin-1 in disease   总被引:164,自引:6,他引:164  
Dinarello  CA 《Blood》1996,87(6):2095-2147
To understand the role of the proinflammatory cytokine interleukin-1 (IL-1) in disease, investigators have studied how production of the different members of the IL-1 family is controlled, the various biologic activities of IL-1, the distinct and various functions of the IL-1 receptor (IL-1R) family, and the complexity of intracellular signaling. Mice deficient in IL-1Beta, IL-1Beta converting enzyme, and IL-1R type I have also been studied. Humans have been injected with IL- 1 (either IL-1alpha or IL-1beta) for enhancing bone marrow recovery and for cancer treatment. The IL-1-specific receptor antagonist (IL-1Ra) has also been tested in clinical trials. The topics discussed in this review include production and activities of IL-1 and IL-1Ra molecules, the effects of IL-1 on gene expression, functions of cell-bound and soluble IL-1 receptors, the importance of the IL-1R accessory protein, newly discovered signal transduction pathways, naturally occurring cytokines limiting IL-1 production or activity, the effects of blocking cyclooxygenase and nitric oxide, and the outcomes of IL-1 and IL-1 Ra in human trials. Special attention is paid to IL-1beta converting enzyme and programmed cell death. The roles of IL-1 in hematopoiesis, leukemia, atherosclerosis, and growth of solid tumors are also discussed. This is a lengthy review, with 586 citations chosen to illustrate specific areas of interest rather than a compendium of references. At the end of each section, a short commentary summarizes what the author considers established or controversial topics linking the biology of IL-1 to mechanisms of disease.  相似文献   
35.
The hematopoietic growth factor CSF-1 has been considered relatively lineage specific for the production of macrophages, whereas GM-CSF elicits a predominance of neutrophils. It is likely that in vivo, individual clones are stimulated by the two CSFs, although the effect of dual stimulation on progenitors and their progeny has not been completely explored. We found that in cultures initiated with low concentrations of CSF-1 or GM-CSF, alone or in combination, production of macrophages predominated. Maximally stimulatory concentrations of CSF-1 elicited a predominance of macrophages, whereas maximal GM-CSF elicited many more neutrophil/macrophage colonies and pure neutrophil colonies. A combination of maximal CSF-1 and GM-CSF elicited the same differentiation as GM-CSF alone. Delayed addition of GM-CSF to cultures initiated with CSF-1 elicited colonies indistinguishable from GM-CSF alone, suggesting that neutrophil production had been switched on by GM- CSF. In mapping studies, colonies initiated by CSF-1 increased or switched on neutrophil production when GM-CSF was added as a second stimulus. These studies show that individual clones are responsive to both CSFs, and that the differentiating influence of GM-CSF predominates over that of CSF-1. In cultures to which only CSF-1 was added, a population of progenitors was sustained that produced neutrophils only after a GM-CSF stimulus. Thus, CSF-1 may participate in maintaining a reserve of progenitors for neutrophils during periods of increased neutrophil demand.  相似文献   
36.
37.
Gastrointestinal tract duplications are uncommon congenital abnormalities. Carcinoma arising from duplication cyst is extremely rare, not to mention metastasis to other organs. We present a case of adenocarcinoma arising from a colonic duplication cyst with invasion of the serosa and metastasis to the omentum in a 40‐year‐old man. Duplication cysts should be included in the differential diagnosis of cystic masses of the gastrointestinal tract. Because these lesions occur so infrequently, they are often not suspected until encountered intraoperatively. The specific findings and advantages of sonography are reviewed. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2011  相似文献   
38.
Fetal persistent middle cerebral artery reversed end diastolic flow is a rare and ominous finding. Previous cases have been associated with intracranial hemorrhage, growth restriction, anaemia, and hepatic anomaly. Intrauterine demise or early neonatal death is a common outcome. We report the case of persistent middle cerebral artery reversed end diastolic flow in a well-grown fetus at 32 weeks’ gestation resulting from acute, severe anaemia due to a large feto-maternal hemorrhage. An emergency cesarean section was performed and the neonate required advanced resuscitation and immediate blood transfusion. Postnatal magnetic resonance imaging confirmed a hemorrhagic parietal infarct and bilateral ischaemic changes in the basal ganglia. This provides further evidence that persistent middle cerebral artery reversed end diastolic flow in any fetus is an ominous finding warranting urgent diagnostic evaluation and/or delivery.  相似文献   
39.
Total radical trapping antioxidant potential (TRAP) and exercise   总被引:1,自引:0,他引:1  
The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.   相似文献   
40.
采用三种设计方案考察了白色念珠菌URM3622胞外分泌生产胶原酶的培养条件。首先进行26—2部分因子试验,结果表明转速和底物浓度对胶原酶的产量影响显著。根据以上结果,又设计了两次连续的23全因子分析,结果表明,在pH7.0、转速160r/min、底物浓度2%条件下培养白色念珠菌,发酵所得胶原酶活性最高。在pH8.2、45℃的环境中,胶原酶活性最大。所获胶原酶在pH7.2~8.2及28~45℃范围内稳定。  相似文献   
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