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排序方式: 共有612条查询结果,搜索用时 15 毫秒
41.
Serge D Van Kriekinge Hidetaka Nishina Muneo Ohba Daniel S Berman Guido Germano 《Journal of nuclear medicine》2008,49(11):1790-1797
Although many patients with heart failure benefit from cardiac resynchronization therapy (CRT), predicting which patients will respond to CRT remains challenging. Recent evidence suggests that the analysis of mechanical dyssynchrony using gated myocardial perfusion SPECT (MPS) may be an effective tool. The aim of this study was to evaluate global and regional gated MPS dyssynchrony measurements by comparing parameters obtained from patients with a low likelihood (LLk) of conduction abnormalities and coronary artery disease and patients with left bundle branch block (LBBB). METHODS: A total of 86 consecutive patients with LLk and 72 consecutive patients with LBBB, all without prior myocardial infarction or sternotomy, were studied using gated MPS. Global (histogram SD [sigma], bandwidth [beta], and entropy [epsilon]) and regional (wall- and segment-based differences of means [Deltamicro(W) and Deltamicro(S), respectively] or modes [DeltaM(W) and DeltaM(S), respectively]) dyssynchrony measures were calculated by Fourier harmonic phase-angle analysis of local myocardial count variations over the cardiac cycle for each patient, and then unpaired t tests were used to determine which parameters were sex-specific and how well they discriminated between the LLk and LBBB populations. Receiver-operating-characteristic analysis was also performed to calculate the area under the curve (AUC), sensitivity (Ss), specificity (Sp), and optimal threshold (Th). RESULTS: Global parameters were found to be sex-specific, whereas regional differences were sex-independent. All parameters studied showed statistically significant differences between the groups (all global, P < 0.05; all regional, P < 0.0001). Receiver-operating-characteristic analysis yielded higher AUC, Ss, and Sp for epsilon and regional parameters (epsilon: AUC = 0.95/0.96, Ss = 94%/88%, Sp = 89%/91%, and Th = 53.9%/60.6% for women/men; Deltamicro(W): AUC = 0.93, Ss = 88%, Sp = 86%, and Th = 10.5 degrees ; Deltamicro(S): AUC = 0.94, Ss = 90%, Sp = 94%, and Th = 9.2 degrees ; DeltaM(W): AUC = 0.95, Ss = 90%, Sp = 94%, and Th = 15 degrees ; and DeltaM(S): AUC = 0.95, Ss = 88%, Sp = 90%, and Th = 10.5 degrees ) than for global parameters (sigma: AUC = 0.75/0.67, Ss = 81%/66%, Sp = 63%/64%, and Th = 16.5 degrees /22.2 degrees for women/men; beta: AUC = 0.80/0.72, Ss = 71%/71%, Sp = 79%/64%, and Th = 69 degrees /81 degrees for women/men). CONCLUSION: The computed parameters all discriminate effectively between LLk and LBBB populations. Measurements that are less dependent on the shape of the phase-angle distribution histogram provided higher sensitivity and specificity for this purpose. Further study is needed to evaluate these parameters for the purpose of predicting response to CRT. 相似文献
42.
This study was undertaken to determine whether selected dietary fibers had an effect on plasma lipoproteins, apolipoproteins and enzymes involved in cholesterol metabolism in rats. Each experimental diet contained 8% dietary fiber by weight; all animals were killed in a nonfasted state. After 4 wk, final body weight and liver cholesterol were similar in fiber-free controls and in rats fed diets containing cellulose, pectin, oat bran or wheat bran. Pectin-fed animals has significantly lower plasma cholesterol, HDL-cholesterol and apolipoprotein A-I levels, and exhibited significantly higher hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase activity than did the fiber-free control group. In addition, plasma triglyceride concentrations were lowest in pectin-fed animals. These multiple effects on lipid metabolism were not observed when oat bran, containing one-third soluble fiber, was used. Although total plasma cholesterol levels in wheat bran-fed animals were not different from those in the fiber-free controls or the cellulose-oat bran-fed animals, the LDL cholesterol level was significantly higher than in fiber-free controls or pectin-fed animals. This study demonstrate that dietary fibers included in the diet of rats are able to alter nonfasting lipoprotein cholesterol and apolipoproteins and that pectin, a soluble fiber, was most effective in lowering plasma cholesterol levels. 相似文献
43.
This study evaluated the use of double-burst stimulation (DBS) in the diagnosis of significant post-operative residual neuromuscular blockade. Ninety patients were allocated to three equal groups. In Group A the degree of residual neuromuscular blockade was assessed by clinical criteria (CC) only; in Group B by CC and manual evaluation of the response to train-of-four (TOF) nerve stimulation; and in Group C by CC, manual evaluation of the response to TOF, and DBS stimulation. Immediately after arrival in the recovery room mechanical twitch was recorded using TOF stimulation. The mean (+/- SD) TOF ratios were 0.53 +/- 0.19 in Group A, 0.67 +/- 0.11 in Group B and 0.81 +/- 0.08 in Group C. The incidence of a TOF ratio of less than 0.7 was 83.3% in Group A, 56.7% in Group B and 6.7% in Group C. It is concluded that the use of DBS enabled the anaesthetist to recognize significant residual block and thus reduced the incidence of post-operative residual neuromuscular blockade. 相似文献
44.
OBJECTIVES: Sepsis or endotoxemia causes diaphragmatic dysfunction, which may contribute to respiratory distress. Toxic free radicals are partly responsible for the pathogenesis. Lidocaine scavenges the reactive molecules. The purpose of the current study was to examine whether lidocaine prevents the diaphragmatic dysfunction of sepsis. DESIGN: Prospective, randomized animal study. SETTING: University research laboratory. SUBJECTS: A total of 40 male Golden-Syrian hamsters. INTERVENTIONS: The animals were randomly allocated to one of five groups (n = 8 each): hamsters undergoing sham laparotomy alone and receiving saline infusion (Sham group), those undergoing cecal ligation with puncture (CLP) and receiving an infusion of saline (Sepsis group), those undergoing sham laparotomy and receiving infusion of lidocaine, 2 mg/kg/hr (Sham-LID group), those undergoing CLP and receiving infusion of lidocaine, 1 mg/kg/hr (Sepsis-LID 1 group), and those undergoing CLP and receiving infusion of lidocaine, 2 mg/kg/hr (Sepsis-LID 2 group). Subcutaneous infusion of saline or lidocaine was started 6 hrs before surgery and continued until 24 hrs after the operation when all hamsters were killed. MEASUREMENTS AND MAIN RESULTS: Diaphragmatic contractility and fatigability were assessed in vitro by using muscle strips excised from the costal diaphragms. Diaphragmatic levels of malondialdehyde (MDA), an index of free radicals-mediated lipid peroxidation, were also measured. Twitch and tetanic tensions in the Sepsis group were reduced compared with the Sham group. Tensions generated during fatigue trials were decreased, and MDA levels were elevated in diaphragms from the Sepsis group. An infusion of 2 mg/kg/hr lidocaine attenuated contractile dysfunction, aggravation of fatigability, and the increase in MDA formation. In contrast, 1 mg/kg/hr lidocaine failed to do so. Electrophysiologic diaphragmatic characteristics in the Sham-LID group were similar to those in the Sham group. CONCLUSIONS: Pretreatment with 2 mg/kg/hr but not 1 mg/kg/hr lidocaine attenuated sepsis-induced diaphragmatic dysfunction in hamsters assessed by contractile profiles and endurance capacity. This beneficial effect of lidocaine may be attributable, in part, to inhibition of lipid peroxidation in the diaphragm. 相似文献
45.
K. Mikawa MD N. Maekawa K. Nishina O. Tanaka H. Yaku H. Obara 《Intensive care medicine》1994,20(1):58-60
We administered surfactant to a 5-month-old infant with respiratory failure due to right pulmonary haemorrhage accompanied
by oedema following abdominal surgery. These pathological conditions were probably precipitated by disseminated intravascular
coagulation and intra-operative excessive administration of fluids, respecitively. Endobronchial instillation of the exogenous
surfactant (120 mg) after selective intubation of the right bronchus produced a dramatic improvement of gas exchange 30 min
after treatment and of chest X-ray findings at 6 h post-treatment. This case on an infant indicates that administration of
surfactant may be one of promising therapeutic approaches to respiratory failure due to pulmonary haemorrhage. 相似文献
46.
BACKGROUND AND STUDY AIMS: It has been reported that the fine mucosal patterns of the gastric pits can be observed with magnification and this may assist in preliminary evaluation prior to histological diagnosis. The aim of this prospective study was to clarify the relationship between the fine mucosal patterns of gastric lesions and histological findings, and also to evaluate the usefulness of magnifying endoscopy during routine endoscopy. PATIENTS AND METHODS: A recently developed magnifying video endoscope, which enables magnification up to 80 times, was used for gastrointestinal endoscopy in 318 patients between January 2000 and January 2001, at the National Shikoku Cancer Center. In total, 232 lesions were detected. However, patients diagnosed by conventional endoscopy as having advanced gastric cancer, malignant lymphoma, or submucosal tumor were excluded from the study. The endoscopic findings for 211 lesions included in this study were compared with the histological findings. RESULTS: Coarse and irregular mucosal patterns were observed in elevated-type cancers by magnifying endoscopy, and in depressed-type cancers there was a finer pit pattern than in the surrounding mucosa, destruction or disappearance of the mucosal microstructure, and abnormal capillary vessels. The magnifying endoscopy results were closely related to the mucosal microstructure observed by dissecting microscopy and to the histological features. The rate of presumptive diagnosis of small gastric cancers was significantly higher when a magnifying endoscope was used compared with conventional endoscopy. In this study, the sensitivity and specificity of magnifying endoscopy as a diagnostic method were 96.0% and 95.5%, respectively. CONCLUSIONS: The fine mucosal patterns and the features of capillary vessels, which were identified with the magnifying endoscope, correlated well with the pathological diagnosis. Magnifying endoscopy will be very useful in predicting the histological diagnosis during routine endoscopic procedures. 相似文献
47.
Deproteinizing methods evaluated for determination of uric acid in serum by reversed-phase liquid chromatography with ultraviolet detection 总被引:2,自引:0,他引:2
We evaluated six deproteinizing methods for determination of uric acid in serum by "high-performance" liquid chromatography with ultraviolet detection: those involving zinc hydroxide, sodium tungstate, trichloroacetic acid, perchloric acid, acetonitrile, and centrifugal ultrafiltration (with Amicon MPS-1 devices). We used a Toyosoda ODS-120A reversed-phase column. The mobile phase was sodium phosphate buffer (40 mmol/L, pH 2.2) containing 20 mL of methanol per liter. Absorbance of the eluate was monitored at 284 nm. The precipitation method with perchloric acid gave high recoveries of uric acid and good precision, and results agreed with those by the uricase-catalase method of Kageyama (Clin Chim Acta 1971;31:421-6). 相似文献
48.
Ando T Mikawa K Nishina K Misumi T Obara H 《The Journal of international medical research》2007,35(1):118-126
Apoptosis of alveolar epithelial type II (AEC-II) cells induced by reactive oxygen species (ROS) contributes to extensive alveolar damage during acute lung injury. Hypercapnic acidosis and hypocapnic alkalosis are known to modulate ROS-mediated lung damage. This study assessed the effects of acid-base balance disturbances on hydrogen peroxide (H2O2)-induced apoptosis of the AEC-II-like human cell line A549, which was cultured under different conditions of pH and CO2 tension (normal pH and CO2, hypercapnic acidosis, metabolic acidosis, hypocapnic alkalosis and metabolic alkalosis). H2O2-induced apoptosis was assessed by a dye-uptake bioassay and induction of caspase activity, which were quantified using analytical digital photomicroscopy. Acidosis or alkalosis of the culture medium alone did not induce A549 cell apoptosis. Hypocapnic alkalosis significantly increased H2O2-induced apoptosis and caspase activation of A549 cells. Metabolic alkalosis non-significantly increased H2O2-induced A549 cell apoptosis and caspase activation. These data suggest that hypocapnic alkalosis intensifies oxidative-induced apoptosis of alveolar epithelial cells. 相似文献
49.
Prostaglandin E1 and tracheal intubation: relationship between the cardiovascular responses and plasma catecholamine concentrations. 总被引:1,自引:0,他引:1
K Mikawa N Maekawa R Goto H Yaku Y Takao K Nishina H Obara 《The Journal of international medical research》1991,19(6):457-464
A study was carried out on 30 normotensive patients (American Society of Anesthesiologists physical status 1) to investigate whether or not a suppressive effect of 0.3 or 0.6 microgram/kg prostaglandin E1 on the hypertensive response to tracheal intubation was due to inhibition of the increase in plasma catecholamine concentrations following the stressful stimulation. A total of 30 patients in three groups underwent elective surgery. Anaesthesia was induced with 5 mg/kg sodium thiopentone given intravenously and tracheal intubation was facilitated by 0.2 mg/kg vecuronium. Either saline (group A) or 0.3 (group B) or 0.6 micrograms/kg (group C) prostaglandin E1 was administered intravenously 15 s before direct laryngoscopy (lasting 30 s) which was attempted 2 min after administering thiopentone and vecuronium. All groups exhibited significant (P less than 0.05) increases in mean arterial pressure, heart rate, rate-pressure product and plasma noradrenaline concentrations following tracheal intubation, but the increases in mean arterial blood pressure and rate - pressure product were significantly (P less than 0.05) less in groups B and C than in group A. Prostaglandin E1, however, enhanced the increase in plasma noradrenaline concentrations following intubation. Data suggest that attenuation of the pressor response to intubation by prostaglandin E1 may not be due to inhibition of the noradrenaline release stimulated by intubation but to inhibition of noradrenaline-induced vasoconstriction. 相似文献
50.
Biochemical studies on the purine metabolism of four cases with hereditary xanthinuria 总被引:1,自引:0,他引:1
T Kojima T Nishina M Kitamura T Hosoya K Nishioka 《Clinica chimica acta; international journal of clinical chemistry》1984,137(2):189-198
The purine metabolism of four cases with marked hypouricemia (serum uric acid concentration of less than 0.018 mmol/l) from three Japanese families was investigated. Erythrocyte adenosine deaminase (EC 3.5.4.4) and purine-nucleoside phosphorylase (EC 2.4.2.1) activities of the patients were within the normal ranges. Urinary hypoxanthine and xanthine concentrations were 0.096-0.397 mmol/l and 0.743-1.717 mmol/l, respectively. Xanthine oxidase (EC 1.2.3.2) activities in the jejunal mucosa of the two normal controls were 0.257 and 0.283 units/g protein, while those of three of the patients were extremely low and could not be determined. The findings of these biochemical features may indicate that the four patients have hereditary xanthinuria. In order to study the purine metabolism in the hypouricemic condition of this disorder, a single oral dose of allopurinol (4-hydroxypyrazolo[3,4-d]pyrimidine) was administered in one case. The excretion pattern of allopurinol and oxypurinol (4,6-dihydroxypyrazolo[3,4-d]pyrimidine) in the urine of the patient was similar to that of a normal control male. These data suggest that some residual enzyme activity may be functioning in vivo, although the presence of xanthine oxidase could not be detected. 相似文献