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OBJECTIVE: The induction of transplantation tolerance across xenogeneic barriers by bone marrow transplantation holds great promise, but engraftment of xenogeneic stem cells has been difficult to achieve. Part of this difficulty is due to species-specific differences in regulatory cytokines and elements of the stromal microenvironment, which we studied here. MATERIALS AND METHODS: We developed a system where fresh bone marrow cells from swine and human are cultured on human bone marrow stroma in order to study these limiting factors in a clinically relevant species combination. RESULTS: We report here the ability of recombinant swine interleukin (IL)-3 and c-kit ligand (KL) to specifically enhance swine hematopoietic chimerism in this system. In the absence of exogenous swine cytokines, there were about half as many swine progenitors as human progenitors at 1, 2, and 4 weeks of culture. When used alone, swine IL-3 led to a notable but transient increase in the relative ratio of swine progenitors, while addition of swine KL increased the ratio of swine progenitors only modestly and only at later time points. In contrast, when swine IL-3 and KL were added together, there was a two- to fourfold increase in the ratio of swine to human progenitors at all times tested. CONCLUSION: These data demonstrate that both swine IL-3 and KL are needed for prolonged enhancement of swine progenitor chimerism under these conditions, and suggest that the species specificity of either one or both of these cytokines may represent an important barrier to prolonged engraftment of swine bone marrow in humans. 相似文献
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IRA Goldsmith FRCS GYH Lip MD MRCP PP Kumar FRCS RL Patel MD FRCS CTh 《International journal of clinical practice》1999,53(1):9-14
To survey the in-hospital morbidity, mortality, length of stay in the intensive therapy unit (ITU) and hospital and quality of life in patients of Indo-Asian origin following coronary artery bypass (CABG) surgery, 345 consecutive patients (mean age 58 years; SD 8.9; range 32-88 years) undergoing primary, isolated CABG were studied. Non-elective CABG was undertaken in 41% of patients. The left anterior descending artery (LAD) was grafted in 89%, although in 30% of these the internal mammary artery (IMA) was not used. Following CABG, the hospital morbidity and mortality was within the expected range, although there was a trend towards higher in-hospital mortality in the Parsonnet low risk group of patients. The length of ITU and hospital stay was not prolonged. Using the SF-36 questionnaire in postoperative patients, low quality of life scores were obtained for six of the eight modalities tested including physical functioning, bodily pain and general health perception. The low quality of life scores and IMA usage in Indo-Asians needs to be addressed. 相似文献
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Spencer Liu H. Steele Holley S. David Stulberg Bruce Cohen 《Journal canadien d'anesthésie》1991,38(3):335-337
A patient is presented who failed to regain consciousness after an apparently uneventful nine-hour revision of a total hip replacement. There were no clinically important haemodynamic changes during the operation, and oxygen saturation, capnography and acid base balance were normal throughout. Postop CT of the head showed a large left MCA infarct with midline shift. At autopsy, the patient was found to have a previously unsuspected patent foramen ovale, and a venous embolus in the left internal carotid artery, which probably had originated from the periprostatic venous plexus with a large infarct in the distribution of the left anterior and middle cerebral arteries. The authors conclude that massive paradoxical venous emboli can occur during surgery with minimal haemodynamic changes. 相似文献
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Dunnick NR; Svetkey LP; Cohan RH; Newman GE; Braun SD; Himmelstein SI; Bollinger RR; McCann RL; Wilkinson RH Jr; Klotman PE 《Radiology》1989,171(1):219-222
Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension. 相似文献