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601.
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
602.
Proteolytic cleavage of human von Willebrand factor induced by enzyme(s) released from polymorphonuclear cells 总被引:2,自引:0,他引:2
In vivo fragmentation of the von Willebrand factor antigen (vWF:Ag) molecule has been demonstrated on radiocrossed immunoelectrophoresis (CIE) in the plasma from patients with disseminated intravascular coagulation, in factor VIII concentrates, and in normal serum. Experiments reported here show that polymorphonuclear (PMN) cells contain a non-calcium-dependent protease(s) that when released and incubated with vWF:Ag results in an additional vWF:Ag peak on radio- CIE. Production of fragments of vWF:Ag by incubation with PMN cells occurred in a time-dependent manner. The protease(s) responsible was inhibited by diisopropyl fluorophosphate, soybean trypsin inhibitor, and aprotinin, but not by benzamidine, azide, epicron, or hirudin. Citrate, EDTA, and leupeptin also had no effect on the PMN cell enzyme's activity, indicating that the enzyme(s) is not calcium dependent. The PMN cell enzyme responsible for vWF:Ag fragmentation is located intracellularly and released by freezethaw lysis or cell activation by calcium or the calcium ionophore A23187. 相似文献
603.
Characterization of fibrinogen Milano I: amino acid exchange gamma 330 Asp----Val impairs fibrin polymerization 总被引:1,自引:0,他引:1
An abnormal fibrinogen was found in two asymptomatic members (father and daughter) of the same family, originating from northern Italy. Routine coagulation studies revealed prolonged thrombin and reptilase clotting times. Plasma fibrinogen levels, as determined by a functional assay, were markedly diminished, whereas the heat precipitation method indicated normal fibrinogen values. On the basis of these findings, a tentative diagnosis of dysfibrinogenemia was made, and according to the accepted nomenclature, this fibrinogen variant was called "fibrinogen Milano l." The time course of fibrinopeptide A and B release from fibrinogen Milano l was normal, but the aggregation of fibrin monomers was delayed. Two-dimensional electrophoresis of reduced variant fibrinogen chains showed a defective gamma-chain with increased cathodic mobility. An abnormal electrophoretic mobility was observed also for the gamma-chain remnants of fibrinogen fragments D1 and D2 derived from fibrinogen Milano l, whereas the charge anomaly was lost after a further digestion by plasmin to D3, suggesting that the structure abnormality of this variant is situated in the region gamma 303-356. An abnormal peptide was isolated after cyanogen bromide cleavage of intact fibrinogen Milano l. This fragment spans from position gamma 311 to gamma 336. Amino acid analysis of the abnormal peptide showed the presence of valine and a diminished content of aspartic acid. Sequence analysis demonstrated an amino acid exchange Asp----Val in the gamma-chain at position 330. 相似文献
604.
AML blast cell progenitors form colonies in culture when stimulated by a media conditioned by leukocytes in th presence of PHA. Two cellular processes occur during colony formation: self renewal generates new progenitors, while others undergo a change that leads to decreased proliferative potential. We tested the effect of the potent tumor promotor, 12-0-tetradecanoyl phorbol acetate (TPA) on these events. TPA was found to be toxic to blast cell colony formation; doses in excess of 1 ng per ml usually abolished it. At doses lower than this, self renewal, as determined by replating either individual or pooled colonies, was increased. At proliferation inhibiting TPA doses, surviving cells showed a spindle morphology, and had increased ANA esterase activity. We interpret the data to mean that TPA decreases blast cell maturation at low doses and may increase it at high doses. 相似文献
605.
Undescended testis: value of MR imaging 总被引:4,自引:0,他引:4
Magnetic resonance (MR) imaging was performed in 32 male patients, 20 with no abnormalities and 12 with clinically suspected undescended testes. The results were compared with ultrasonographic, computed tomographic, clinical, and surgical findings. The undescended testes were unilateral in eight patients (one had testicular duplication) and bilateral in four. Of 16 undescended testes, 15 were correctly identified on MR images. One intraabdominal testis was not seen. Testis-fat contrast at 0.35 T was optimal with a short repetition time (TR) and a short echo time (TE). At 1.5 T, good contrast was achieved with short TR/TE sequences, but the contrast was even more pronounced with even longer TR/TE parameters. In seven patients with unilateral undescended testes, the undescended and contralateral testes showed symmetrical tissue signal intensity on both T1- and T2-weighted images. In three, the undescended testis was of lower signal intensity, suggesting atrophy. MR imaging promises to become an important diagnostic tool in the detection of undescended testes. 相似文献
606.
Early diagnosis of nonviable pregnancy with endovaginal US 总被引:3,自引:0,他引:3
The mean diameter of the gestation sac and the presence or absence of a yolk sac or embryo and/or cardiac pulsations on endovaginal ultrasound (US) images were correlated with normal and abnormal outcomes of pregnancy. Sixty-two patients who were less than 10 weeks pregnant (menstrual age) underwent endovaginal US. In 59 patients with gestation sacs greater than or equal to 8 mm, the absence of a yolk sac predicted a nonviable pregnancy with a sensitivity of 67% and a specificity of 100%. In 35 patients with gestation sacs greater than or equal to 16 mm, the absence of an embryo predicted a nonviable pregnancy with a sensitivity of 50% and a specificity of 100%. When the absence of cardiac pulsations was added to the latter group of patients, the sensitivity was 100% and the specificity was 100%. The combination of these criteria (gestation sac size; demonstration of yolk sac, embryo and/or cardiac pulsations) enabled the early (less than 10 weeks menstrual age) diagnosis of a nonviable pregnancy with endovaginal US. 相似文献
607.
CT of the pulmonary nodule: a cooperative study 总被引:31,自引:0,他引:31
Zerhouni EA; Stitik FP; Siegelman SS; Naidich DP; Sagel SS; Proto AV; Muhm JR; Walsh JW; Martinez CR; Heelan RT 《Radiology》1986,160(2):319-327
To evaluate the role of computed tomography (CT) in the investigation of pulmonary nodules, a special reference phantom that enabled CT densitometric measurements independent of variations between scanners and patients was used in ten institutions. A total of 384 nodules not considered calcified by conventional methods were examined; 118 (31%) proved to be benign, and in 65 of these (55%), unsuspected calcification was demonstrated. In 28 of the 65, definite calcification could be identified on thin-section CT scans by simple inspection of the scans at narrow windows. In the remaining 37, presence of calcification could not be clearly established without comparison with the reference CT number from the calibration phantom. CT was most effective in establishing the benignancy of nodules 3 cm or less in diameter and those with discrete or smooth margins. CT rarely yields a confident diagnosis of benign disease in larger nodules and in those with irregular or spiculated borders. After review of prior spot radiographs, low kilovolt peak spot radiographs, and conventional tomograms, the authors conclude that thin-section CT aided by a reference phantom in equivocal cases should be an integral part of the diagnostic approach to the pulmonary nodule. 相似文献
608.
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