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71.
Long-Term Evaluation of the Ventricular Defibrillation Energy Requirement   总被引:1,自引:0,他引:1  
Defibrillation Energy Requirements. Introduction : Defibrillation energy requirements in patients with nonthoracotomy defibrillators may increase within several months after implantation. However, the stability of the defibrillation energy requirement beyond 1 year has not been reported. The purpose of this study was to characterize the defibrillation energy requirement during 2 years of clinical follow-up.
Methods and Results : Thirty-one consecutive patients with a biphasic nonthoracotomy defibrillation system underwent defibrillation energy requirement testing using a step-down technique (20, 15, 12, 10, 8, 6, 5, 4, 3, 2, and 1 J) during defibrillator implantation, and then 24 hours, 2 months, 1 year, and 2 years after implantation. The mean defibrillation energy requirement during these evaluations was 10.9 ± 5.5 J, 12.3 ± 7.3 J, 11.7 ± 5.6 J, 10.2 ± 4.0 J, and 11.7 ± 7.4 J, respectively ( P = 0.4). The defibrillation energy requirement was noted to have increased by 10 J or more after 2 years of follow-up in five patients. In one of these patients, the defibrillation energy requirement was no longer associated with an adequate safety margin, necessitating revision of the defibrillation system. There were no identifiable clinical characteristics that distinguished patients who did and did not develop a 10-J or more increase in the defibrillation energy requirement.
Conclusion : The mean defibrillation energy requirement does not change significantly after 2 years of biphasic nonthoracotomy defibrillator system implantation. However, approximately 15% of patients develop a 10-J or greater elevation in the defibrillation energy requirement, and 3% may require a defibrillation system revision. Therefore, a yearly evaluation of the defibrillation energy requirement may he appropriate.  相似文献   
72.
Many oligopeptide crystals show the β-pleated sheet structures. Both parallel and antiparallel chain pleated sheets are found, and also both ideal (flat) and heavily twisted sheets are found. The structural parameters, such as the T (NCα-C') angles, the torsion angles (φ and ø), the fiber axis periods, the hydrogen bond lengths, and the interchain spacings, are studied. Some of them deviate signifi cantly from those proposed by Pauling & Corey (Proc. Natl. Acad. Sci. US (1953), 39, 253–256). In the heavily twisted sheets, the twists are larger than those in the globular proteins, and each two neighboring chains are almost per pendicular with each other, preserving the β-sheet type hydrogen bond system. The torsion angles in the twisted sheets are rather close to those of the poly (L-proline) II helix. It also is discussed that the (NCαC) angles sometimes deviate by almost 5° from the standard value depending on the structures of the main and side chains.  相似文献   
73.
Four patients with advanced non-Hodgkin's lymphoma of unfavorablehistology were treated with marrow-lethal doses of cyclophosphamide(CY) and total body irradiation (TB1) followed by the infusionof cryopreserved autologous marrow. All four patients showedengraftment after autologous bone marrow transplantation andachieved complete remission (CR). Three of them, however, developedrelapse in 1.7, 12.9 and 14.5 mo respectively after the transplantation.The other patient has survived in drug-free CR for more than16.6 mo. There was no treatment-related death although therewere some tolerable complications. These data suggest that theCY-TBI regimen may be effective in inducing CR in patients withadvanced non-Hodgkin's disease but it does not contribute topreventing relapse.  相似文献   
74.
We report a case of a young child affected by triple cancerswho developed a pleomorphic rhabdomyosarcoma of the retroperitoneumfollowing prophylactic chemotherapy after surgery for doubleprimary adrenocortical carcinoma and ganglioneuroblastoma. It is suggested that genetic susceptibility and chemotherapymight be responsible for the development of rhabdomyosarcomaas the second malignant neoplasm.  相似文献   
75.
76.
Plasma renin activity (PRA) and aldosterone concentration (PAC) were determined in normal infants aged 20 days to 1 year as well as in normal neonates and older children. The responses of PRA and PAC to five intramuscular injections of synthetic ACTH-Z at 6-hour intervals while on replacement cortisol therapy were also studied in nine infants with salt-losing type of congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH) of varying severity, using the data obtained in normal infants as control. The mean PRA and PAC decreased with age from the neonatal period, but in infants aged 20 days to 3 months these variables remained as high as those in newborns. They were also remarkably higher in infants aged 4 to 12 months than in older children. In two cases of CAH (cases 1 and 2) where salt wasting symptoms had been only transiently observed during the neonatal period, PAC was markedly elevated in response to ACTH administration, while in the remaining seven infants with CAH (cases 3–9) with persistent salt wasting symptoms, PAC was not elevated at all or only slightly so. PRA, on the other hand, increased with time during the ACTH stimulation in cases 3–9, while it increased and then decreased in cases 1 and 2. These findings suggest that the salt-wasting symptoms in CAH may arise where there is a tendency toward renal salt loss due to the overproduction of ACTH-dependent steroids characteristic of this disease, and cannot be compensated for by sufficient secretion of aldosterone. In cases 3–9, the maximal PAC under the ACTH stimulation was 17–44 ng/dl. These levels are comparable to or even higher than the normal range for control older children aged 2–8 years, but the levels were inappropriately low for the marked elevation of PRA in all of them when compared with the mean level in normal infants. Therefore, these data also seem to explain at least in part the well known clinical fact that the salt wasting symptoms in CAH are severe during infancy, requiring the administration of mineralocorticoids in addition to cortisol. However, beyond infancy only the replacement cortisol therapy is necessary to remit the symptoms.  相似文献   
77.
In order to determine the histological changes after a singleinfusion of bleomycin (BLM) into the aortic esophageal artery(BLM A.I.), resected specimens from 58 patients with esophagealcarcinoma (27 cases with BLM A.I., 14 untreated cases, 13 caseswith radiation therapy and four cases with combined therapyof radiation and BLM) were examined and evaluated by Feulgenmicrospectrometry for nuclear deoxyribonucleic acid (DNA) content.The histological changes following the BLM A.I. were characterizedby degeneration and necrosis at the front of the invading carcinomatissue accompanied by inflammatory cell infiltration with foreignbody giant cells and fibrosis. In comparison with untreatedcases, BLM-treated cases showed an increase in nuclear DNA contentand a wide dispersion of the DNA values especially at the perinecroticarea and at the front of advancing carcinoma nests. Therefore,a histological effect of the BLM A.I. was shown by the measurementof the nuclear DNA content of carcinoma cells.  相似文献   
78.
Dynamic ECG Changes in Brugada Syndrome. We present a patient with Brugada syndrome in whom 12-lead ECXis were recorded just before and after an episode of ventricular fibrillation (VF). A progressive elevation of both the RS-T segment and J waves just preceding and following the VF, and a close relationship between the amplitude of the RS-T segment and the preceding R-R intervals during atrial fibrillation, were documented. These findings support the hypothesis that RS-T elevation and a subsequent VF are related to a transient outward current-mediated spike-and-dome morphology of the epicardial action potential.  相似文献   
79.
A case of primary splenic lymphoma in a patient with chronic hepatitis C is reported. A 69-year-old man with chronic hepatitis C was admitted to Fukuoka City Hospital for evaluation of an enlarging splenic tumour. In the spleen, ultrasonographic examination revealed a hypoechoic tumour and computed tomography demonstrated a non-enhancing low density area measuring 7 cm in diameter; coeliac angiography revealed a hypovascular tumour. Gallium scintigraphy showed uptake of the radioisotope in the splenic tumour. A splenectomy was performed and the morphological and immunohistochemical findings of this tumour were compatible with those of non-Hodgin's B cell lymphoma. Recently, cases of malignant B cell lymphoma associated with hepatitis C virus infection have been reported. Lymphotropism of hepatitis C virus may play a pathological role in the development of non-Hodgkin's lymphoma. We emphasize the importance of considering lymphoma in the differential diagnosis of extrahepatic disorders during the course of chronic hepatitis C virus infections.  相似文献   
80.
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