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41.
42.
Marrow transplantation with or without donor buffy coat cells for 65 transfused aplastic anemia patients 总被引:4,自引:3,他引:4
Storb R; Doney KC; Thomas ED; Appelbaum F; Buckner CD; Clift RA; Deeg HJ; Goodell BW; Hackman R; Hansen JA; Sanders J; Sullivan K; Weiden PL; Witherspoon RP 《Blood》1982,59(2):236-246
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%). 相似文献
43.
AIMS: HisPurkinje block induced by incremental atrial pacingis highly predictive of an impending high degree atrioventricularblock in patients with bifascicular block. The His potentialis, however, sometimes not measurable or is lost in the ventriculardepolarization. The aim of this study was to evaluate whetherthe comparison of RR intervals before and after atrioventricularblock, induced by incremental atrial pacing, could differentiatebetween atrioventricular nodal and HisPurkinje blockin patients with bifascicular block. METHODS AND RESULTS: In 98 patients with bifascicular block, incremental atrial pacingwas performed as part of an invasive electrophysiological study.An RR index was constructed by calculating thenumerical difference between the RR interval immediately beforeand after the atrioventricular block divided by the RR intervalimmediately before the pacing-induced block. Endocavitary recordingof the His bundle potential was used for defining the levelof atrioventricular block. The median RR index was 0·98(range 0·881·02) in recordings with HisPurkinjeblock and 0·49 (range 0·110·89)in recordings with atrioventricular nodal block (P<0·001).An RR index of 0·85 had a sensitivity of 100% and a specificityof 99% for the identification of atrioventricular block localizedto the HisPurkinje system. CONCLUSION: The use of an RR index is a helpful tool in the differentiationof HisPurkinje from atrioventricular nodal block in patientswith bifascicular block undergoing incremental atrial pacingas part of an invasive electrophysical study. 相似文献
44.
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels. 相似文献
45.
Grafted neural stem cells develop into functional pyramidal neurons and integrate into host cortical circuitry 总被引:39,自引:0,他引:39
Englund U Bjorklund A Wictorin K Lindvall O Kokaia M 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(26):17089-17094
In vitro expanded neural stemprogenitor cells can undergo region-specific differentiation after transplantation to the developing or adult brain, and display morphologies and markers characteristic of mature neurons. Here we have used patch-clamp techniques to explore whether grafted stem cells also can develop physiological properties of mature neurons and become functionally integrated within host neural circuitry. The immortalized neural progenitor cell line, RN33B, prelabeled with GFP by using a lentiviral vector, was transplanted into the cortex or hippocampus of neonatal rats. We found that the grafted GFP-positive cells differentiated into cells with morphological features of cortical or hippocampal pyramidal neurons, and that many of them had established appropriate cortico-thalamic and contralateral hippocampal connections, respectively, as revealed by retrograde tracing. Whole-cell patch-clamp recordings from grafted cells with morphological characteristics of pyramidal neurons showed that they were able to generate action potentials, and received functional excitatory and inhibitory synaptic inputs from neighboring cells. These data provide evidence that grafted neural progenitors can differentiate into morphologically mature pyramidal projection neurons, establish appropriate long-distance axonal projections, exhibit normal electrophysiological properties, and become functionally integrated into host cortical circuitry. 相似文献
46.
47.
48.
J Tang DJ Humes E Gemmil NT Welch SL Parsons JA Catton 《Annals of the Royal College of Surgeons of England》2013,95(5):323-328
Introduction
The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.Methods
Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.Results
There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).Conclusions
The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality. 相似文献49.