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81.
In two cases with recurrent sustained ventricular tachycardia (VT) due to re-entry, the response pattern to extrastimuli during the tachycardia was studied. In each case, right ventricular extrastimuli with longer coupling intervals during VT were followed by fully compensatory pauses and with shorter coupling intervals reset the tachycardia cycle. In one case, a plateau was produced by a single extrastimulus, resembling that seen in the response curve of sinus node automaticity as well as ectopic atrial tachycardia. Two successive stimuli produced three definite zones, i.e., fully compensatory, reset producing a plateau, and progressive prolongation zones with shortening of the coupling intervals between the two stimuli, and terminated the tachycardia with further shortening of the coupling intervals. In conclusion, resetting phenomenon was confirmed on two cases with re-entrant VT. This phenomenon cannot be used as a criterion to determine the mechanism responsible for VT.  相似文献   
82.
83.
A case of malignant mesenchymoma of the liver is reported. Thediagnosis was confirmed on the surgical specimen. The patientshowed marked hypercalcemia. Parathyroid hormone assay was negative.  相似文献   
84.
85.
Comparative studies of the blood level, tissue distribution,excretion, inactivation, adsorption, metabolic accelerators,and substances having chemical affinity were made for mitomycinC, 5 fluorouracil, bleomycin, actinomycin D, daunomycinand chromomycinA3. Blood level, tissue distribution, excretion, inactivation, etc.of a drug were closely related to eachother; for example, themaximum blood level correlated with the rates of adsorptionor inactivation by tissues. Drugs with different chemical structure but with similar modeof action, such as actinomycin D, daunomycin and chromomycinA3, show acommon body distribution pattern. The mechanism of inactivation sometimes resembled that of activation.Therefore, it wasassumed that the study on inactivation wouldbe useful in clarifying the mode of action of drugs.  相似文献   
86.
Human mercaptalbumin (HMA) and nonmercaptalbumin (HNA) could be separated by high-performance liquid chromatography (HPLC) at neutral pH. Using HPLC, the present authors found the nonmercapt-mercapt conversion (HNA ← HMA) during hemodialysis and the mercapt-nonmercapt conversion (HMA ← HNA) after hemodialysis in chronic renal failure, indicating HMA as the covalent carrier protein for sulfur-containing amino acids.  相似文献   
87.
BACKGROUND: There are only a few reports discussing the characteristics of intussusception developing in school-age children. The characteristics of these cases are discussed, with reference to previous literature. METHODS: The present study included eight cases of intussusception in school-age children among 143 intussusception patients treated on an inpatient basis at Nihon University Itabashi Hospital, during the 11 year period from 1993 to 2003. The remaining 135 patients were assigned to the infant group as controls. The clinical characteristics of intussusception in school-age children were compared with those of the condition developing in infants. RESULTS: The eight children of school age with intussusception ranged in age from 8 to 15 years (mean, 11.6 years), and consisted of five boys and three girls. The major symptom was abdominal pain, occurring in 100% (8/8). Bloody stools and vomiting were reported in two patients each (25%) from this group. The triad of abdominal pain, bloody stools and vomiting was recognized in only one child (12.5%) of this group. Two children (25.0%) had a palpable abdominal mass, and one child (12.5%) complained of diarrhea. None of the school-age children with intussusception had any antecedent infection; five, two and one patients had the ileo-colic type, ileo-ileo-colic type and ileo-ileal type of intussusception, respectively. Four underwent enema reduction and four underwent surgical reduction. One of the eight children (12.5%) had underlying organic abnormality; in the remaining children the condition was labeled idiopathic. One child developed recurrences. CONCLUSIONS: In school-age children intussusception is generally believed to be commonly secondary to underlying organic abnormality, but in the present study only one of eight school-age children had underlying organic abnormality; in the remaining children, the condition was labeled idiopathic. The major symptom in school-age intussusception was abdominal pain. Therefore this may need to be differentiated from appendicitis in children of school age. It is considered that abdominal ultrasonography (USG) is a simple and useful method for making the diagnosis of intussusception, and that diagnostic USG should be conducted in all school-age children presenting with acute abdominal pain.  相似文献   
88.
BACKGROUND: The three major signs of hemolytic uremic syndrome (HUS) are hemolytic anemia, thrombopenia and acute renal failure. HUS is classified into Shiga toxin-mediated HUS (Stx-HUS) and non-Shiga toxin-mediated HUS (nStx-HUS). The prognosis of nStx-HUS is reported to be less favorable than that of Stx-HUS. Although the association between the prognosis and pathological characteristics of HUS have been reported such that the prognosis was considered to be poor for thrombotic microangiopathy (TMA) with predominant arterial involvement (arterial TMA), good for TMA with predominant glomerular involvement (glomerular TMA) and dependent on the extent of necrosis in cases of renal cortical necrosis, it is not yet clear whether pathological findings are also related to the renal prognosis of nStx-HUS cases. Therefore the purpose of the present paper was to analyze renal biopsy findings and prognosis for five children with nStx-HUS. METHODS: Clinical records of five cases of nStx-HUS among 74 cases of diagnosed HUS were reviewed, and information and data were summarized. RESULTS: Histological examination of the kidney led to the diagnosis of arterial TMA in three cases, and glomerular TMA and severe renal cortical necrosis in one case each. Analysis of the relationship between renal histological findings and the prognosis found that three patients with arterial TMA and one patient with severe renal cortical necrosis later developed end-stage renal failure while one patient with glomerular TMA has continued to show normal renal function. CONCLUSIONS: These findings indicate that pathological findings are closely related to the prognosis in cases of nStx-HUS.  相似文献   
89.
Efficacy and safety of laparoscopic surgery for pheochromocytoma   总被引:4,自引:0,他引:4  
OBJECTIVE: Laparoscopic surgery for primary aldosteronoma and Cushing's syndrome is well established. We report on our experiences with laparoscopic adrenalectomy for pheochromocytoma, and assess the efficacy and safety of the laparoscopic approach. METHODS: Between April 1998 and April 2003, a total of 23 patients underwent laparoscopic adrenalectomy for pheochromocytoma at Chiba University Hospital and Yokohama Rosai Hospital, Japan. We compared the surgical outcomes of these patients with those of 106 patients with adrenal tumors due to other pathologies who underwent laparoscopic adrenalectomy during the same period. RESULTS: The mean tumor size of pheochromocytoma was 4.96 cm. Mean operative time was 192.7 min, and mean estimated blood loss was 130 mL. Neither mean operative time nor mean estimated blood loss was greater for patients with pheochromocytoma. Intraoperative hypertension (systolic blood pressure > 180 mmHg) occurred in 39.1% (9/23) of patients with pheochromocytoma. During the follow-up period, there were no mortalities or recurrences of endocrinopathy. CONCLUSIONS: Laparoscopic adrenalectomy for pheochromocytoma is a safe and minimally invasive procedure.  相似文献   
90.
Abstract  Although respiration in trained canines is well investigated, the process of preparing dogs has not been described in any great detail. Moreover, their daytime patterns of sleep and wakefulness during 1 or 2 h of electroencephalogram (EEG) and electrocardiogram (ECG) recordings are not clear. Therefore, we describe the process of selecting and training dogs, in which we recorded EEG and ECG in the laboratory. First, 14 of 1242 dogs dealt with over a 1 year period were chosen. They were trained for 2 h to lie quietly and to sleep in the laboratory; this training procedure was repeated 152 times. Three dogs were then selected and a permanent tracheostomy was performed in one. Finally, EEG and ECG were recorded with the bipolar fine needle electrodes; respiration was recorded simultaneously through a tube inserted to a tracheostomy in one dog. Wakefulness, slow wave sleep (SWS) and rapid eye movement (REM) sleep (REMS) were identified according to the EEG pattern and on the basis of the behavioral criteria. Recordings were performed 12 or 13 times in each dog. Complete sleep cycles, including wakefulness, SWS and REMS in this sequence, were observed 3.9–4.1 times. The mean duration of SWS was 2.2–4.4 min and that of REMS was 3.5–4.6 min. The REMS latency was 33.9–41.8 min. Fluctuation of heart rate with respiration, termed respiratory sinus arrhythmia, was noted in the ECG. Heart beat increased with inspiration and decreased with expiration. The present study demonstrates how to select and train sleeping dogs and shows their undisturbed daytime sleep and wakefulness patterns.  相似文献   
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