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81.
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   
82.
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   
83.
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   
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Two human hematopoietic cell lines (TYS and TYH) with monocytic characteristics were derived from the peripheral blood of a patient with acute myelomonocytic leukemia and of another with a follicular large-cell type of malignant lymphoma. The TYS cells, derived from the leukemia patient, revealed a monocytic appearance with microvilli at one side and had many granules and vacuoles. They showed strongly positive reactions with α-NBE, NASDAE, and AcP, and were reactive with monoclonal antibodies such as Oklal, 12 and B1. The TYS cells, which phagocytized carbon particles and antibody-coated SRBC but not latex particles, released lysosomal enzymes and tu- moricidal factor into the supernatant. The TYH cells, derived from the malignant lymphoma patient, had abundant cytoplasm and pseudopods detectable by electron microscopy with a monocytoid appearance and virus-like particles in the cytoplasm. They showed strongly positive reactions with α-NBE, NASDAE and β-Gase, but no reactivity with monoclonal antibodies or with surface markers except Fc-γ-R. TYH cells phagocytized latex particles very well. Two different human monocyte-histiocyte lineages were thus established. During culture, the TYS and TYH cells maintained their characteristics over 28 and 16 months of Passage, respectively.  相似文献   
86.
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   
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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   
90.
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   
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