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Identification of T lymphocytes in human mixed hemopoietic colonies 总被引:11,自引:0,他引:11
The addition of a T-cell growth-promoting medium (PHA-TCM) to culture conditions that support growth of multi-lineage hemopoietic colonies enhances the proliferation of cells with lymphoid morphology within these colonies. These cells were identified as T lymphocytes by their ability to form rosettes with SRBC and their reaction with monoclonal antibodies (OKT3, OKT4) directed against T-cell-specific surface components. They continue to proliferate extensively under the influence of PHA-TCM after transfer of mixed colonies into liquid suspension culture. Supportive evidence for a common progenitor of myeloid and lymphoid cells within single mixed colonies is provided by Y-chromatin body analysis of E-rosette positive and negative cells in colonies grown in cocultures of male and female bone marrow cells. 相似文献
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Reversal of granulocyte adherence to nylon fibers using local anesthetic agents: possible application to filtration leukapheresis 总被引:1,自引:0,他引:1
The effects of the cationic anesthetic agents tetracaine and lidocaine on granulocyte function, morphology, and adherence to nylon fibers were studied in an attempt to improve current methods of granulocyte collection by filtration leukapheresis (FL). When dissolved in acid- citrate-dextrose (ACD) plasma, these drugs significantly increased granulocyte elution from the fibers in a dose-related fashion. Granulocytes exposed to tetracaine and lidocaine remained more than 95% viable, retained normal bactericidal capacity after the drugs were washed from the cells, and had preserved membrane integrity, as evidenced by the normal ultrastructural appearance of tetracaine- exposed cells and an absence of leakage of lysozyme or lactic dehydrogenase. Granulocytes eluted with the anesthetic agents were rounded in shape with a reduction in the number of filopodial cytoplasmic projections and a relative absence of cytoplasmic vacuolization when compared to granulocytes eluted with ACD plasma alone. Dose-related inhibition of phagocytosis and adherence, which was largely reversible after washing the granulocytes, was noted. Greater than 95% of the lidocaine could be removed from the eluate with a single centrifugation and resuspension, indicating that granulocytes prepared by FL with anesthetic-enhanced elution could be potentially transfusable. 相似文献
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G. Minoli M.D. V. Terruzzi M.D. A. Ferrara M.D. A. Casiraghi M.D. F. Rocca M.D. H. Rainer M.D. A. Porro M.D. G. C. Butti M.D. P. G. Mandelli M.D. R. Piffer M.D. P. Lampertico M.D. 《The American journal of gastroenterology》1984,79(2):95-97
Results of a multicenter prospective study on the relationships between benign gastric ulcer, Candida, and medical treatment is reported. In a group of 66 patients, mycetes were seen in six cases (9.1 %). Candida-contaminated ulcers were diagnosed solely by histological examination, with periodic acid-Schiff staining being more effective than hematoxylin and eosin staining. All contaminated ulcers were healed by treatment either with cimetidine alone, or combined cimetidine-carbenoxolone, without antimycotics. No cases of Candida-contaminated ulcers were seen after 6 wk of treatment. The finding of contamination was more common in older patients. Under the conditions of our study, Candida-contamination of benign gastric ulcers does not affect the rate of healing, does not need specific treatment, and has no particular endoscopic features. Cimetidine or carbenoxolone treatment was not associated with persistence of the fungus. 相似文献
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Mark P Maskery Christian Holscher Stephanie P Jones Christopher I Price W David Strain Caroline L Watkins David J Werring Hedley CA Emsley 《Journal of cerebral blood flow and metabolism》2021,41(1):14
Stroke mortality and morbidity is expected to rise. Despite considerable recent advances within acute ischemic stroke treatment, scope remains for development of widely applicable neuroprotective agents. Glucagon-like peptide-1 receptor agonists (GLP-1RAs), originally licensed for the management of Type 2 Diabetes Mellitus, have demonstrated pre-clinical neuroprotective efficacy in a range of neurodegenerative conditions. This systematic scoping review reports the pre-clinical basis of GLP-1RAs as neuroprotective agents in acute ischemic stroke and their translation into clinical trials. We included 35 pre-clinical studies, 11 retrospective database studies, 7 cardiovascular outcome trials and 4 prospective clinical studies. Pre-clinical neuroprotection was demonstrated in normoglycemic models when administration was delayed by up to 24 h following stroke induction. Outcomes included reduced infarct volume, apoptosis, oxidative stress and inflammation alongside increased neurogenesis, angiogenesis and cerebral blood flow. Improved neurological function and a trend towards increased survival were also reported. Cardiovascular outcomes trials reported a significant reduction in stroke incidence with semaglutide and dulaglutide. Retrospective database studies show a trend towards neuroprotection. Prospective interventional clinical trials are on-going, but initial indicators of safety and tolerability are favourable. Ultimately, we propose that repurposing GLP-1RAs is potentially advantageous but appropriately designed trials are needed to determine clinical efficacy and cost-effectiveness. 相似文献
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Platelet concentrates were prepared at twice the normal concentration and stored at room temperature for 7 days in either standard bags (controls) or bags to which 1 or 2 g of Amberlite resin beads charged with dibasic phosphate had been added. The resin beads served as a buffer system by providing a "slow release" form of phosphate ions as well as by binding CO2 produced during platelet metabolism. Control platelets demonstrated rapid falls in pH, ATP content, morphology score, and thrombin-induced nucleotide release after 24 hr of storage with a fall in pH to less than 6.0 by day 3. Profound ultrastructural changes and a rise in pO2, suggesting loss of platelet viability, accompanied these changes. In contrast, the resin-stored platelets remained near normal after 24 hr of storage, with preservation of discoid morphology, 95% of ATP levels, excellent ultrastructural appearance, and evidence of continued oxygen consumption after 3 days of storage. Even after 7 days of storage, ATP levels remained greater than 50% of baseline and ultrastructurally intact platelets were seen. In the 1-g resin bags the pH remained at baseline levels (6.9-7.0), while there was a rise in pH in the 2-g resin bags. These results demonstrate the beneficial effects of maintaining a higher pH during platelet storage and provide a new approach to studying the metabolic changes that occur during longer term storage. 相似文献
40.
During the period from January 1970 until December 1973, therapy was started in 41 previously untreated adolescents and adults with acute lymphoblastic leukemia. Induction therapy was started with vincristine and prednisone in all patients, resulting in complete remission in 19 and death due to infection during the first month in one case. After 3 wk on these two drugs, the addition of daunorubicin was required in the remaining 21 patients. Fifteen of these obtained remission, one died during induction therapy, and five patients were unresponsive to this therapy, as well as to all subsequent induction schemes. The overall remission rate was 83%. Significantly higher initial leukocyte counts were found in the group treated with vincristine, prednisone, and daunorubicin. Meningeal leukemia prophylaxis, by either periodic methotrexate injections given intrathecally or a combination of cranial irradiation and intrathecally administrated methotrexate, was administered in 29 therapy responders. The median duration of complete remission obtained with various maintenance therapy schemes was 13 mo. No differences were seen in the results obtained in patients between 14 and 20 yr of age and older patients. Twenty-two patients relapsed within 2-37 mo. Relapses were confined to the central nervous system in two cases, to the bone marrow in 18, and to the bone marrow and CNS simultaneously in two. A second remission was obtained in 17 cases (77%). The median survival time of the whole group was 27 mo, as compared with 32 mo for therapy responders and 7 mo for the nonresponders. The percentage and duration of remission and the survival time in our group of adolescents and adults were comparable to those currently being achieved in other centers, but not as good as those reported for children treated with the same protocols. 相似文献