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61.
Adverse reactions to xenon-enhanced CT cerebral blood flow determination   总被引:7,自引:0,他引:7  
Latchaw  RE; Yonas  H; Pentheny  SL; Gur  D 《Radiology》1987,163(1):251-254
Fourteen institutions performed 1,830 computed tomographic (CT) cerebral blood flow (CBF) examinations with 32% inhaled stable xenon. Respiratory rate delay greater than 10 seconds occurred in 3.6% of patients, with 83% of the delays lasting 10-15 seconds. There was no incident of prolonged respiratory difficulty. Headache (0.4%), seizures (0.2%), nausea and vomiting (0.2%), and change in neurologic status (0.1%) were uncommon, and there were no transient ischemic attacks. The CT CBF method with 32% inhaled stable xenon is thus associated with an acceptably low incidence of adverse reactions.  相似文献   
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A multiparametric heart rate variability analysis was performed to prove if combined heart rate variability (HRV) measures of different domains improve the result of risk stratification in patients after myocardial infarction. In this study, standard time domain, frequency domain and non-linear dynamics measures of HRV assessment were applied to 572 survivors of acute myocardial infarction. Three parameter sets each consisting of 4 parameters were applied and compared with the standard measurement of global heart rate variability HRVi. Discriminant analysis technique and t-test were performed to separate the high risk groups from the survivors. The predictive value of this approach was evaluated with receiver operator (ROC) and positive predictive accuracy (PPA) curves. Results - The discriminant analysis shows a separation of patients suffered by all cause mortality in 80% (best single parameter 74%) and sudden arrhythmic death in 86% (73%). All parameters of set I show a high significant difference (p<0.001) between survivors and non-survivors based on two-tailed t-test. The specificity level of the multivariate parameter sets is at the 70% sensitivity level (ROC) about 85–90%, whereas HRVi shows maximum levels of 70%. The PPA in the all cause mortality group is at the 70% sensitivity level twice as high as the univarihate HRV measure and increases to more than fourfold as high within the VT/VF group. In conclusion, in this population, the multiparametric approach with the combination of four parameters from all domains especially from NLD seems to be a better predictor of high arrhythmia risk than the standard measurement of global heart rate variability.  相似文献   
64.
Abstract. Primary tracheal epithelial cells obtained from two fetuses with cystic fibrosis (CF) were successfully transfected with a plasmid vector recombined with the large T oncogene of SV40. The resulting tracheal cells were propagated in culture for up to 25 passages and retained the mutations of the CF genes carried by the two fetuses, one heterozygous for the S549N and N1303K substitutions (CFT-I cells), and the other homozygous for the most common deletion ΔF508 (CFT-2 cells). The transfected cells: (a) expressed the SV40 large T oncogene, as determined by immunofluorescence and Northern blot analysis; (b) retained typical epithelial morphology, as assessed by the presence of microvilli, desmosomes, gap junctions, and cytokeratin expression; (c) were fully responsive to the cAMP-stimulating agents isproterenol, forskolin and vasoactive intestinal peptide for cAMP production and PKA activation; (d) do not produce any tumour in the athymic nude mice; (e) were diploid and tetraploid with a normal chromosomal complement at early passages, and (f) exhibited the abnormal regulation of chloride conductance characteristic of CF.
These results indicate that CFT-1 and CFT-2 cells constitute a suitable model for: (a) comparison of the maturation and function of the CFTR protein mutated in the two nucleotide-binding domains; (2) analysis of the biochemical defect in CF epithelial airway cells, (c) development of new therapeutic agents, and correction of the CF defect by gene replacement therapy in vitro .  相似文献   
65.
Severe Jarisch Herxheimer reaction (J-HR) precipitated by antibiotic treatment of louse-borne relapsing fever (LBRF) is associated with a transient, marked rise in circulating tumour necrosis factor alpha (TNF alpha), interleukin 6 (IL-6) and interleukin 8 (IL-8). Ovine polyclonal anti-TNF alpha antibody fragments (Fab) were used in a randomized double blind placebo controlled trial in an attempt to prevent this reaction. Within 4 h after penicillin, in controls (n = 29), a several- fold rise in cytokines occurred, concomitant with a fall in spirochaetes and maximal clinical manifestations of the J-HR. An intravenous infusion of anti-TNF alpha Fab, 30 min before penicillin in 20 patients reduced peak plasma levels of IL-6 and IL-8 (but not IL-1 beta) compared with controls (p = 0.01 and < 0.001, respectively) and the incidence of the J-HR, indicating some neutralization of TNF alpha. An apparent fall in TNF alpha reflected interference of anti-TNF alpha in the immunoassay.   相似文献   
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67.
Background: A continuous popliteal sciatic nerve block (CPSNB) has been performed with increasing frequency for post‐operative analgesia after foot surgery. Major complications associated with the placement of a perineural catheter remain rarely studied. The aim of this study was to prospectively determine the incidence of major complications (neurological and infectious) in post‐operative adult patients with a continuous popliteal catheter inserted by the anatomical posterior approach for analgesia after foot surgery. Methods: All popliteal catheters were placed pre‐operatively under sterile conditions with the aid of a nerve stimulator technique. The primary outcome measure was the incidence of major complications including infection and neuropathy. As a secondary outcome, adverse effects as well as other complications were also evaluated. Data were expressed as median [25th–75th percentiles]. Results: A total of 400 patients were included in the study during a 2‐year period. The median time the catheter remained indwelling was 47 h [23, 54]. Major complications included three events (0.75%) with one infection (0.25%) and two neuropathies (0.50%). Three blocks were unsuccessful and the catheter insertion was difficult in 12 patients (3%). During the CPSNB procedure, one patient reported slight paraesthesia during stimulation. Patient satisfaction was scored at 4 for 89%, 3 for 6% and 2 for 5% on the analogue scale. Conclusions: Major complications after the use of CPSN are not in fact rare. The incidence of severe neuropathy or infection complications is, respectively, 0.50% and 0.25%. However, the insertion of CPSN could be considered effective and is associated with only a few minor complications.  相似文献   
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69.
Davidson  HD; Abraham  R; Steiner  RE 《Radiology》1985,155(2):371-373
Three patients who had complete agenesis and two patients who had partial agenesis of the corpus callosum (ACC) underwent magnetic resonance (MR) imaging. In addition to excellent visualization of the indirect signs of ACC, direct vivid display (short T1) of the corpus callosum on sagittal images allowed better evaluation of subtle abnormalities than has been possible with other modalities. Associated abnormalities were also well-displayed. MR is the initial procedure of choice in evaluation of the corpus callosum.  相似文献   
70.
1临床资料患儿,女性,4岁。因间断性腹痛1月加重伴黑便15d,呕吐2d入院。患儿病前无明确外伤史,其母于入院前15d发现左膝部有损伤痕,已愈合,行腹部B超检查,提示肝胆肾正常,胰大小正常,边界清,实质回声均匀,主胰管不扩张,肝前区肝肾夹角及脾肾夹角可见53mm的液性暗区,内见肠管蠕动  相似文献   
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