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971.
Electroconvulsive therapy (ECT) is an appropriate clinical model to investigate blood flow during seizures. In this study cerebral blood flow velocity (CBFV) was measured during 40 ECTs in 10 patients by means of transcranial Doppler sonography. EEG was recorded continuously. Under general anesthesia, the pre-convulsive blood flow velocity (Vmean) decreased significantly. After ECT, we measured a dramatic increase in Vmean which was significantly greater in the left MCA than in the right MCA. After termination of seizures, flow velocities returned to baseline levels. The striking increase in cerebral blood flow velocity reflects excessive cerebral metabolism during convulsive neuronal activation. The left hemisphere seems to be more sensitive to electrical stimuli as was indicated by its predominant augmentation of CBFVs.  相似文献   
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'Blown pack' spoilage of vacuum-packed chilled beef, lamb and venison, and of a cooked meat product, chilled dog rolls packed in an oxygen-impermeable plastic casing, was characterised by sensory, chemical and microbiological analysis. Investigation of the probable causative agents led to the isolation of eight strains of psychrotrophic clostridia. Three strains have been provisionally identified as C. difficile, C. beijerinckii and C. lituseburense; the other five remain unidentified. In inoculation studies only one isolate produced significant amount of gas on meat, causing pack 'blowing'. It is, therefore, possible that 'blown pack' spoilage involves a synergism with one or more other organisms.  相似文献   
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Transplantation of peripheral blood progenitor cells (PBPCs) has largely replaced autologous bone marrow transplantation. The same might occur in the allogeneic setting if the favourable initial experience with allogeneic PBPCT is confirmed. We analysed all primary transplants utilizing unmodified PBPC from HLA-identical sibling donors reported to the European Group for Blood and Marrow Transplantation (EBMT) for 1994. 59 patients with a median age of 39 years received myeloablative therapy for acute myelogenous leukaemia (23 patients, acute lymphoblastic leukaemia (13), chronic myelogenous leukaemia (nine), lymphoma (seven), or other diagnoses (seven) mostly of advanced stages followed by transplantation of allogeneic PBPC. Three patients died soon after grafting, the others showed prompt haemopoietic recovery with median times to recover an absolute neutrophil count (ANC) above 0.5 and 1.0 x 10(9)/I of 15 (range 9-27) and 17d (range 10-28) respectively. Time to platelet recovery above 20 or 50 x 10(9)/I was 16 (range 9-76) and 18d (range 12-100) respectively. 27 patients (46%) developed no or mild acute graft-versus-host disease (GVIID). The incidence of moderate (grade II) disease was 27%; 24% of the patients developed severe acute GVHD (grades III or IV), 55% of patients who were alive 90d after transplantation developed chronic GVHD, the probability to develop extensive chronic GVHD was 32% (95% confidence interval 22-42) with a median follow-up of 14 months. Overall and event-free survival (EFS) at 1 year were 54% (CI 48-60) and 50% (CI 43-57), respectively, the relapse incidence was 23% (CI 17-29). EFS was 67% (CI 55-79) in patients transplanted for acute leukaemias in first complete remission, chronic myelogenous leukaemia in first chronic phase, or severe aplastic anaemia. Transplantation of allogeneic PBPC resulted in prompt and durable engraftment. The incidence and severity of acute and chronic GVHD seemed comparable to that observed after allogeneic BMT. Overall and event-free survival in this cohort of patients, most of whom suffered from advanced leukaemia or lymphoma, is encouraging, suggesting that the high numbers of T lymphocytes and/or natural killer cells contained in a typical PBPC collection product exert a vigorous graft-versus-leukaemia effect. Further evaluation of allogeneic PBPCT is highly desirable.  相似文献   
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We identified the cell cycle status of CD34(+) cells of steady-state bone marrow (BM) and peripheral blood (PB) obtained from healthy volunteers, and those of apherasis PB samples collected from healthy donors who had been administered granulocyte colony-stimulating factor (G-CSF). More than 10% of CD34(+) cells in BM were in S+G2/M phase. In contrast, regardless of whether G-CSF treatment was performed, less than 2% of CD34(+) cells in PB were cycling. BM CD34(+) cells showed greater VLA-4 expression and adherence to stromal cells than PB CD34(+) cells. In addition, when cycling and dormant BM CD34(+) cells were analyzed separately, the cells in S+G2/M phase expressed more VLA-4 and adhered to the stromal cell monolayer more efficiently than the cells in G0/G1 phase. Furthermore, this adhesion of CD34(+) cells to the stromal cell layer was almost completely inhibited by anti-VLA-4 antibody. Taken together, these results suggest that CD34(+) progenitors in G0/G1 phase of the cell cycle differ from those in S+G2/M phase in adhesiveness mediated by VLA-4 in the hematopoietic microenvironment.  相似文献   
980.
AIM: To determine reproducibility and accuracy of the Nikon Retinomax autorefractor when used with children who were made cycloplegic. METHODS: Autorefraction and retinoscopy or subjectively refined retinoscopy (where, under the patient's direction, the refraction was varied until the best visual acuity was achieved) were performed on the right eye of 47 children, age 11-93 months. Autorefraction was performed using the Nikon Retinomax, which provides up to eight measured values of refractive error and one representative measurement of refractive error. RESULTS: Autorefractor measurements were successfully obtained from 7/9 children age 3 years or younger, and from all older children. Vector methods were used to calculate differences. Retinomax reproducibility averaged 0.43 D. Unbiased Retinomax and retinoscopy measurements differed by an average of 0.82 D. Unbiased Retinomax and subjectively refined retinoscopy differed by an average of 1.03 D. CONCLUSIONS: Reproducibility of Retinomax measured values in children is comparable with reproducibility of retinoscopy, subjective refraction, and autorefraction measurements in adults. Agreement between Retinomax and retinoscopy and agreement between Retinomax and subjective refinement in children is comparable with agreement between autorefraction and subjective refraction in adults. The study indicates that the Retinomax is a useful instrument for measuring refractive errors in young children.  相似文献   
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