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41.
The relationships between histological findings, adaptively increased cytochrome a(+a3) levels in chronic liver disease and complications after hepatectomy were studied in order to clarify the mechanism of mitochondrial derangement. The liver specimens of 53 hepatectomized patients were randomly evaluated by three independent hepatopathologists and were compared with cytochrome a(+a3) levels in the biopsied liver, the extent of operation and postoperative complications. The cytochrome a(+a3) concentrations did not show any significant difference between cases of chronic hepatitis and liver cirrhosis nor groups classified by regeneration. Severity of piecemeal necrosis was categorized into three groups: group A--minimal (n = 20); group B--moderate (n = 19); and group C--severe (n = 14). There were significant differences (P less than 0.01) in cytochrome a(+a3) concentrations between the groups (A: 99 +/- 9; B: 135 +/- 6; C: 155 +/- 10 pmol/mg of mitochondrial protein). Extensive hepatectomy, involving segmentectomy or more, was frequently complicated (four of nine, 44.4%) in group C, whereas there were few complications (two of 16, 12.5%) in group A cases in which extensive hepatectomy was performed. Evidence will be presented which will show that deranged liver function, as indicated by cytochrome a(+a3) levels, is closely correlated with piecemeal necrosis. This may be attributed to the damage of periportal hepatocytes which are the main sites of oxidative phosphorylation.  相似文献   
42.
Risk of Lung Cancer by Histologic Type among Smokers in Miyagi Prefecture   总被引:2,自引:1,他引:1  
Smoking habits of the 827 lung cancer patients aged 40 yearsor over who were treated in the Sendai Kosei Hospital from 1977–82were compared with those in the general population of a non-metropolitandistrict in northern Japan, which we recently surveyed by mailquestionnaire. The relative risks of lung cancer by histologictype adjusted by age and area of residence were as follows:1.9 for adenocarcinoma, 4.3 for squamous cell carcinoma, 3.9for small cell carcinoma and 3.4 for large cell carcinoma inmen, and 2.9, 6.4, 4.5 and 4.0 for these histologic types, respectively,in women. These elevated risks were all statistically significant(p < 0.05). These findings suggest that smoking habits shouldbe carefully considered when studying the etiology of any celltype of lung cancer, even adenocarcinoma, which often has beenthought to be unrelated to smoking habits.  相似文献   
43.
In order to assess the effectiveness of chest irradiation inaddition to intensive chemotherapy in limited stage small celllung cancer, 50 patients were randomized to receive either chemotherapyalone or chemotherapy plus chest irradiation, between April1981 and October 1985. The chemotherapy regimen consisted ofa four-drug combination of cyclophosphamide, vincristine, methotrexate,and procarbazine, and a three-drug combination of etoposide,adriamycin, and nimustine, given alternately every 8 weeks.One group of 26 patients received the chemotherapy alone, andanother group of 24 patients received chest irradiation with40 Gy between cycles 1 and 2 of the chemotherapy. Complete responserates were quite similar in the two groups; 50% for those receivingchemotherapy alone, and 59% for those receiving chemotherapyplus chest irradiation. There were no significant differencesin median survival (15 months versus 12 months) and in long-termsurvival rates between the two groups with a median follow-upperiod of 26 months. The combined modality treat ment was moretoxic than chemotherapy aIone two patients receiving such treatmentdied of radiation pneumonitis. It is concluded that chest irradiationcombined with chemotherapy does not affect the response rate,survival, or pattern of recurrence in patients with limitedstage small cell lung cancer.  相似文献   
44.
Abstract: A 59-year-old male with an established diagnosis of malignant melanoma of the nasal cavity plus multiple pulmonary metastases was referred to our hospital because of abdominal pain and vomiting. Double-contrast study of the small intestine revealed a filling defect in the middle of the ileum. lntraoperative enteroscopy revealed that the ileal tumor was ulcerated, and that it was covered by ileal mucosa of normal appearance. Because no other lesions were identified within the intestine, the ileal segment with the tumor was surgically removed. The tumor was diagnosed as malignant melanoma with a histology similar to that of nasal mass. The patient has survived for the subsequent 13 months, during which no gastrointestinal symptoms recurred. Our case suggests that metastasis should be included in the differential diagnosis of a single small intestinal tumor. (Dig Endose 1999; 11: 47–51)  相似文献   
45.
Background: Type-1 long-QT syndrome (LQT1) is caused by mutations in the KCNQ1 gene. The purpose of this study was to investigate whether KCNQ1 mutations in highly conserved amino acid residues within the voltage-gated potassium channel family are associated with an increased risk of cardiac events.
Methods and Results: The study population involved 492 LQT1 patients with 54 missense mutations in the transmembrane region of the KCNQ1 channel. The amino acid sequences of the transmembrane region of 38 human voltage-gated potassium channels were aligned. An adjusted Shannon entropy score for each amino acid residue was calculated ranging from 0 (no conservation) to 1.0 (full conservation). Cox analysis was used to identify independent factors associated with the first cardiac event (syncope, aborted cardiac arrest, or death). Patients were subcategorized into tertiles by their adjusted Shannon entropy scores. The lowest tertile (score 0–0.469; n = 146) was used as a reference group; patients with intermediate tertile scores (0.470–0.665; n = 150) had no increased risk of cardiac events (HR = 1.19, P = 0.42) or aborted cardiac arrest/sudden cardiac death (HR = 1.58, P = 0.26), and those with the highest tertile scores (>0.665; n = 196) showed significantly increased risk of cardiac events (HR = 3.32, P <0.001) and aborted cardiac arrest/sudden cardiac death (HR = 2.62, P = 0.04). The increased risk in patients with the highest conservation scores was independent of QTc, gender, age, and beta-blocker therapy.
Conclusions: Mutations in highly conserved amino acid residues in the KCNQ1 gene are associated with a significant risk of cardiac events independent of QTc, gender, and beta-blocker therapy.  相似文献   
46.
Antigenicity of eggs (oncospheres), cysticercoids and adults (with immature segments only) of the bile duct tapeworm Hymenolepsis microstoma was analysed using immunoblotting techniques and indirect immunofluorescent antibody (IFA) techniques with immune sera of BALB/c mice (i) infected with different doses of cysticercoids, (ii) during patent or prepatent infection with the lumen phase of the parasite or (iii) sensitized with live or dead eggs. Antibody responses detected by IFA test and immunoblotting showed that antigenicity of eggs (oncospheres) differed from that of cysticercoids and adults. Single worm infections were sufficient to stimulate antibody responses. Mice which had patent infection showed strong antibody responses to all three (egg (oncosphere), cysticercoid, adult) antigens, while mice given two prepatent infections showed some antibody responses to cysticercoid and adult antigens only. Although the normal intermediate hosts of this parasite are arthropods, antibodies to some major egg (oncosphere) antigens were produced in mice given eggs of this parasite orally, either through inoculation of eggs or ingestion of faeces contaminated with eggs. Antibodies were not produced in mice dosed with non-viable eggs. The results are consistent with the hypothesis that cestode parasites express phase- (or stage-) specific antigens.  相似文献   
47.
Two patients with recurrent supraventricular tachycardia are presented. The tachycardia was initiated and terminated by atrial extrastimulation beyond the atrial relative refractory period and the atrial activation sequence during the tachycardia was low to high. The induction of tachycardia was dependent on a critical AH interval. In patient 1 who had ventriculoatrial conduction, the tachycardia was initiated by the premature ventricular stimulation followed by double atrial response. In patient 2 the ventriculoatrial conduction was not observed. In both patients, the unchanged atrial cycle length during the tachycardia with antegrade Wenckebach AH block was observed. When AH block occurred during tachycardia the first AH interval was shorter than the subsequent HA interval. In patient 2 verapamil (5 mg) prolonged the atrial cycle length during tachycardia and rapid intravenous injection of adenosine triphosphate (10 mg) terminated the tachycardia. Oral diltiazem (280 mg/day) suppressed the tachycardia in patient 1. These findings suggest that the mechanism of tachycardia may be fast-slow type of AV nodal reentry in the upper portion of the AV node and this type of arrhythmia has tendency to show incessant form.  相似文献   
48.
To determine whether time- and frequency-domain analyses differ in their ability to predict sustained ventricular tachycardia (VT) induced by programmed ventricular stimulation, 60 consecutive patients with myocardial infarction and 30 healthy control subjects were evaluated. Programmed ventricular stimulation using three extrastimuli and signal-averaged ECG recordings were performed in patients with myocardial infarction. Of the 60 patients, sustained monomorphic VT (SMVT) with cycle length (CL) ± 250 ms (slow SMVT) was inducible in 9, and SMVT with CL < 250 ms (fast SMVT) was inducible in 9. The durations of the filtered QRS (f-QRS) at each high-pass filter (25, 40, and 80 Hz) and the low amplitude signal (LAS) at 25-Hz high-pass filtering were significantly longer in the slow SMVT group than in the fast SMVT, no VT, or normal control group. The root-mean- square voltages at 25-Hz and 8Q-Hz high-pass filters in the slow SMVT group were significantly lower than in the fast SMVT, no VT, or normal control group. There was no significant difference in time- domain variables among fast SMVT, no VT, and normal control groups. The CL of the induced sustained VT was significantly correlated with the durations of f-QRS and LAS, Concerning frequency-domain variables (area ratio and factor of normality), there was no significant difference between slow and fast SMVT groups. Both the slow and fast SMVT groups had a significantly higher area ratio and a significantly lower factor of normality than the group with no VT or the normal control subjects. In conclusion, there were significant correlations between time-domain variables and CL of SMVT, while there was no correlation when using frequency-domain parameters.  相似文献   
49.
Electrophysiological studies can be useful in the presence of idiopathic ventricular fibrillation (VF) and may be used when selecting antiarrhythmic drugs. However, the yield, the mode, and the long-term reproducibility of the induction of VF have not yet been fully elucidated. Eight patients with idiopathic VF underwent electrophysiological study. The mean age (± SD) was 45 ± 17 years. Six were males and two were females. Diagnosis was done by exclusion. VF was induced in 6 (75%) of 8 patients using double extra stimuli at coupling intervals of 233 ± 39 and 191 ± 20 ms for the first and second extra stimuli, respectively. Of note, VF was induced by stimulation exclusively at the origin of the premature ventricular beat, which was the first complex of VF in two patients. In another patient, VF was initiated by two premature stimuli and also by a pause produced by rapid pacing. The inducibility of VF was reproduced 9–18 months after the first induction in all of the four patients studied. When the ability of antiarrhythmic drugs to suppress VF inducibility was confirmed, no recurrence was observed during the follow-up period of 40–160 months, but a recurrence of VF was observed in one of two nonresponders. In one patient, amiodarone administration failed in preventing VF induction 9 months after initiation of therapy, and reassessment of long-term drug-efficacy might be indicated in some patients. In conclusion, idiopathic VF was highly inducible (75%) with double extra stimuli. In this study, it was induced from a specific site (2/8) or by a pause (1/8). Induction of VF seemed to be reproduced 9–18 months after the first study. The outcome was considered favorable when the inducibility of VF was suppressed by antiarrhythmic drugs.  相似文献   
50.
The retrograde atrial potential at a successful ablation site is usually obscured by the wide and large ventricular potential during atrioventricular reentrant tachycardia or ventricular pacing, which makes it difficult to determine the appropriate ablation site for concealed accessory pathway. A pacing maneuver named the “simultaneous pacing method” is proposed herein to differentiate the retrograde atrial potential from the ventricular potential for a successful ablation of the concealed accessory pathway. Catheter ablation was performed in 12 patients with a single left free-wall concealed accessory pathway. The atrial insertion site was determined by the simultaneous pacing method in six patients (group I) and by ventricular pacing in six patients (group II), In the simultaneous pacing method, electrograms recorded during ventricular pacing in the earliest retrograde atrial activation site are a fusion of the ventricular potential and the following retrograde atrial potential. When atrial and ventricular pacings are performed simultaneously (simultaneous pacing), the end portion of the electrograms recorded at the same site is solely the ventricular component, because atrial is activated earlier. The atrial potential can be confirmed during ventricular pacing in comparison with the electrograms during the “simultaneous pacing.” Radiofrequency catheter ablation was successful in eliminating conduction through the accessory pathway in all 12 patients. The radiofrequency applications in group I were significantly fewer than those in group II (1.7 ± 1.0 in group I, 5.3 ± 3.2 in group II, P < 0.05). The total procedure time in group I was significantly shorter than in group II (57.8± 15.7 vs 106.7 ± 41.6 mins in group II. respectively, P < 0.05). The fluoroscopy time in group I was significantly shorter than in group II (54.0 ± 7.9 vs 81.3± 26.3 mins, respectively, P < O.05). We were able to determine the atrial insertion site of accessory pathways by the simultaneous pacing method. The simultaneous pacing method was useful in eliminating concealed left free-wall accessory pathways.  相似文献   
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