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601.
602.
Bergeron RJ; Streiff RR; Creary EA; Daniels RD Jr; King W; Luchetta G; Wiegand J; Moerker T; Peter HH 《Blood》1993,81(8):2166-2173
A comparative study of the iron-clearing properties of subcutaneously administered desferrioxamine B (DFO) with those of orally administered desferrithiocin sodium salt (1), desmethyl desferrithiocin (2), desazadesmethyl desferrithiocin sodium salt (3), desazadesmethyl desferrithiocin pivaloyloxymethyl ester (4), and desazadesmethyl-5,5- dimethyl desferrithiocin (5) in an iron-loaded Cebus monkey model and a non-iron overloaded bile duct-cannulated rat model is presented. All six drugs, which performed well in rodent studies, demonstrated increased efficiency in the Cebus monkey model. When administered to rodents at a daily dosage of 384 mumol/kg over a period of 10 days, drug 1 demonstrated severe renal toxicity. whereas drugs 3, 4, and 5 exhibited severe gastrointestinal (GI) toxicity. Under the same experimental protocol, drug 2 did not show significant toxic side effects. In addition, to further evaluate the iron-clearing properties of analogue 2, a dose-response study was performed in the primates that showed that iron excretion increased in a dose-dependent fashion. 相似文献
603.
604.
Biologic properties in vitro of a recombinant human granulocyte- macrophage colony-stimulating factor 总被引:33,自引:3,他引:33
Metcalf D; Begley CG; Johnson GR; Nicola NA; Vadas MA; Lopez AF; Williamson DJ; Wong GG; Clark SC; Wang EA 《Blood》1986,67(1):37-45
Recombinant human granulocyte-macrophage colony-stimulating factor (rH GM-CSF) was purified to homogeneity from medium conditioned by COS cells transfected with a cloned human GM-CSF cDNA and shown to be an effective proliferative stimulus in human marrow cultures for GM and eosinophil colony formation. The specific activity of purified rH GM- CSF in human marrow cultures was calculated to be at least 4 X 10(7) U/mg protein. Clone transfer experiments showed that this proliferation was due to direct stimulation of responding clonogenic cells. Acting alone, rH GM-CSF did not stimulate erythroid colony formation, but in combination with erythropoietin, increased erythroid and multipotential colony formation in cultures of peripheral blood cells. rH GM-CSF had no proliferative effects on adult or fetal murine hematopoietic cells, did not induce differentiation in murine myelomonocytic WEHI-3B cells, and was unable to stimulate the survival or proliferation of murine hematopoietic cell lines dependent on murine multi-CSF (IL 3). rH GM- CSF stimulated antibody-dependent cytolysis of tumor cells by both mature human neutrophils and eosinophils and increased eosinophil autofluorescence and phagocytosis by neutrophils. From a comparison of these effects with those of semipurified preparations of human CSF alpha and -beta, it was concluded that rH GM-CSF exhibited all the biologic activities previously noted for CSF alpha. 相似文献
605.
Lipid hydroperoxides permit deformation-dependent leak of monovalent cation from erythrocytes 总被引:3,自引:0,他引:3
Subtle peroxidative perturbation of normal red blood cells (RBC) using t-butylhydroperoxide creates a leak pathway for monovalent cations that is reversibly activated by cell deformation. To determine what factor promotes expression of this unique membrane defect, we have dissected "peroxidation" into components that can be evaluated separately by comparing K leak from suitably modified RBC during elliptical deformation and parallel control incubation. Selective introduction of phospholipid hydroperoxides into normal RBC membranes successfully induces a deformation-dependent leak pathway having the same phenomenology as that previously documented for cells treated with t- butylhydroperoxide itself (fully recoverable; calcium-independent; inhibited at lower pH; K efflux balanced by Na influx). This leak pathway occurs in the absence of detectable secondary peroxidative change and appears to reflect a direct influence of lipid hydroperoxide. Using micropipette examination of vesicular bilayers reconstituted from RBC lipid extracts, we find that lipid from peroxidized RBC exhibits only a slight tendency to be less cohesive than normal lipid, apparently precluding isolated lipid properties as an explanation for altered permeability barrier function. However, addition of a hydrophobic membrane-spanning peptide to these same lipids significantly diminishes bilayer cohesion, an effect that is exacerbated further by the presence of peroxidized lipid. These observations suggest that lipid hydroperoxide is a necessary, but perhaps not sufficient, factor for induction of this unique leak pathway. Our results may be relevant to the abnormal cation homeostasis of sickle RBC in which deformation of an oxidatively perturbed membrane occurs during the sickling phenomenon. 相似文献
606.
EA Operskalski ; ER Schiff ; SH Kleinman ; M Busch ; PE Taylor ; WP Parks ; H Lee ; PA Tomasulo ; E Donegan ; M Stuart ; et al. 《Transfusion》1989,29(8):746-748
We interviewed 51 blood donors in four major US metropolitan areas subsequently found to have had antibodies to human T-cell lymphotropic virus (anti-HTLV) in late 1984-early 1985. Sixteen donors (31%) reported that they or a sexual contact had a history of blood transfusion. Twelve donors (24%) reported that they or a sexual contact used intravenous drugs. Ten donors (20%) were blacks born in the southeastern US. Four of the male donors (15%) reported homosexual contact. The most common characteristic was an association with Japan or the Caribbean basin (61%). These results show a broader variation of epidemiologic backgrounds than anticipated. 相似文献
607.
DC Kandiloros MD PHD GA Goletsos MD PHD TP Nikolopoulos MD PhD EA Ferekidis MD PhD AS Tsomis MD PhD GK Adamopoulos MD PHD 《International journal of clinical practice》1997,51(2):69-70
SUMMARY In this study we investigated the possible relationship of laryngeal cancer and subclinical lead intoxication, using the depression of aminolevulinic acid dehydratase (ALAD) activity in blood as indicator. Twenty-six patients with laryngeal cancer and 53 normal controls met the criteria to enter the study. Blood ALAD activity values in the patients with laryngeal cancer ranged from 27.1 to 75.3 U/l with a mean of 50.79 U/l. The respective values in the control group ranged from 36.2 to 98 U/l with a mean of 59.76 U/l. There was a statistically significant difference between the two means (0.001 <p<0.01), whereas blood lead concentrations in all patients were within normal limits. These findings support the hypothesis that low level lead intoxication (subclinical blood lead levels), from cars, industries and products, may contribute to the risk of laryngeal cancer. Further investigation is needed to clarify the exact relationship between lead and cancer of the larynx. 相似文献
608.
609.
Mohamed A. Abdelgawad Della G.T. Parambi Mohammed M. Ghoneim Nasser Hadal Alotaibi Abdulaziz Ibrahim Alzarea Abdullah S. Alanazi Ahmed Hassan Sara M. Tony Mohamed EA Abdelrahim 《International wound journal》2022,19(8):2092
A meta‐analysis was performed to assess the effect of surgical site wound infections and risk factors in neonates undergoing surgery. A systematic literature search up to January 2022 incorporated 17 trials involving 645 neonates who underwent surgery at the beginning of the trial; 198 of them had surgical site wound infections, and 447 were control for neonates. The statistical tools like the dichotomous or continuous method used within a random or fixed‐influence model to establish the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to evaluate the risk factors and influence of surgical site wound infections in neonates undergoing surgery. Surgical site wound infections had significantly higher mortality with OR value 2.03 at 95% CI 1.40–2.95 with P‐value <0.001, the longer length of hospital stay (MD, 31.88; 95% CI, 18.17–45.59, P < 0.001), and lower birthweight of neonates (MD, −0.30; 95% CI, −0.53 to −0.07, P = 0.01) compared with neonates with no surgical site wound infections undergoing surgery. However, no remarkable change was observed with surgical site wound infections in the gestational age at birth of neonates (MD, −0.70; 95% CI, −1.46 to 0.05, P = 0.07), and the preoperative antibiotic prophylaxis (OR, 1.28; 95% CI, 0.57–2.87, P = 0.55) compared with no surgical site wound infections for neonates undergoing surgery. Surgical site wound infections had significantly higher mortality, a longer length of hospital stay, and lower birthweight of neonates. However, they had no statistically significant difference in the gestational age at birth of neonates and the preoperative antibiotic prophylaxis compared with no surgical site wound infections for neonates undergoing surgery. Furthermore, evidence is needed to confirm the outcomes. 相似文献
610.
AA Polydorou EV Pantiora A Vezakis P-T Arkoumanis CJ Psichogios EA Kontis Georgios P Fragulidis G Polymeneas 《Hellēnikē cheirourgikē. Acta chirurgica Hellenica》2018,90(1):9-15