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81.
Schuening FG; Appelbaum FR; Deeg HJ; Sullivan-Pepe M; Graham TC; Hackman R; Zsebo KM; Storb R 《Blood》1993,81(1):20-26
The effects of recombinant canine stem cell factor (rcSCF) on hematopoiesis were studied in normal dogs and in dogs given otherwise lethal total body irradiation (TBI) without marrow transplant. Results were compared with previous and concurrent data with recombinant granulocyte colony-stimulating factor (rG-CSF). Four normal dogs received 200 micrograms rcSCF per kilogram body weight daily either by continuous intravenous infusion for 28 days (n = 2) or by subcutaneous (SC) injection in two divided doses for 20 days (n = 2). All dogs showed at least a twofold increase in peripheral blood neutrophil counts starting approximately 7 days after the initiation of treatment. Hematocrit level and monocyte, lymphocyte, eosinophil, reticulocyte, and platelet counts were not elevated. Marrow sections after rcSCF treatment showed panhyperplasia. The only toxicity was facial edema during the first few days of rcSCF administration, presumably caused by mast cell stimulation. Ten dogs were given 400 cGy TBI at 10 cGy/min from two opposing 60Co sources. They were given no marrow infusion and received 200 micrograms/kg/d rcSCF SC in two divided doses for 21 days starting within 2 hours of TBI. Five of the 10 dogs showed complete and sustained hematopoietic recovery and survived as compared with 1 of 28 control dogs not receiving growth factor (P < .005). RcSCF treatment allowed for hematopoietic recovery in two of seven dogs administered 500 cGy of TBI but in none of five dogs given 600 cGy of TBI. Results with rcSCF are similar to those obtained with rG-CSF. The rate of neutrophil recovery in rcSCF-treated dogs after 400 cGy TBI was not different from that of rG-CSF-treated dogs (P = .65), but the rate of platelet recovery was faster (P = .06) in the rcSCF-treated animals. Combined treatment with rcSCF and rcG-CSF after 500 cGy TBI did not result in strongly improved survival as compared with results obtained with either factor alone. 相似文献
82.
Bcl-x rather than Bcl-2 mediates CD40-dependent centrocyte survival in the germinal center 总被引:7,自引:2,他引:7
Both rapid B-cell proliferation and programmed cell death (PCD) occur during the differentiation and selection of B cells within the germinal center. To help elucidate the role of Bcl-x in B-cell antigen selection and PCD within the germinal center, we examined its expression in defined B-cell populations and by immunochemistry of tonsil tissue. Purified B-cell fractions enriched for centrocytes express high amounts of Bcl-x and relatively low amounts of Bcl-2, whereas fractions enriched for centroblasts lack significant levels of both proteins. Consistent with this observation, immunocytochemistry localized Bcl-x within cells scattered throughout the germinal center. Stimulation of tonsil B cells with either CD40 or Staphylococcus aureus Cowan increase bcl-x mRNA and protein levels. Treatment of a cell line with a germinal center phenotype (RAMOS) or the tonsillar B-cell centroblast fraction with CD40 rapidly increased Bcl-x levels and partially rescued B cells from PCD. These data suggest that Bcl-x rather than Bcl-2 may rescue centrocytes during selection in the germinal center. 相似文献
83.
NICHOLAS J TALLEY SK LAM KL GOH KM FOCK 《Journal of gastroenterology and hepatology》1998,13(4):335-353
Dyspepsia is most optimally defined as pain or discomfort centred in the upper abdomen. The symptom complex may be caused by peptic ulcer disease, gastro-oesophageal reflux, or gastric cancer but is most often due to functional (or non-ulcer) dyspepsia. While upper endoscopy is the method of choice to determine the underlying cause of dyspepsia, it is expensive. A more pragmatic approach is needed in the Asia-Pacific region where health services are limited. A detailed treatment algorithm is given for managing patients presenting with new-onset dyspepsia and documented functional dyspepsia after endoscopy, and evidence to support this approach is reviewed. Prompt endoscopy is recommended for patients with alarm features. In patients without alarm features, treatment for 2–4 weeks with an empirical anti-secretory or prokinetic agent, followed by investigation using non-invasive Helicobacter pylori testing and treatment for patients who do not respond or relapse, is recommended. Trials of management strategies are now needed to establish the efficacy and cost-effectiveness of the approaches recommended. 相似文献
84.
85.
86.
Human breast lesions: characterization with proton MR spectroscopy 总被引:31,自引:0,他引:31
87.
88.
Clustering of mutations in the biotin-binding region of holocarboxylase synthetase in biotin-responsive multiple carboxylase deficiency 总被引:4,自引:2,他引:2
Dupuis L; Leon-Del-Rio A; Leclerc D; Campeau E; Sweetman L; Saudubray JM; Herman G; Gibson KM; Gravel RA 《Human molecular genetics》1996,5(7):1011-1016
Holocarboxylase synthetase (HCS) catalyses the biotinylation of the four
biotin-dependent carboxylases found in humans. A deficiency in HCS results
in biotin-responsive multiple carboxylase deficiency (MCD). We have
identified six different point mutations in the HCS gene in nine patients
with MCD. Two of the mutations are frequent among the MCD patients
analyzed. Four of the mutations cluster in the putative biotin- binding
domain as deduced from the corresponding Escherichia coli enzyme and
consistent with an explanation for biotin-responsiveness based on altered
affinity for biotin. The two others may define an additional domain
involved in biotin-binding or biotin-mediated stabilization of the protein.
相似文献
89.