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91.
1) Pituitary hormone secretion of 14 acromegalic patients was studied before treatment. Incidence of hyporeactive response was 0%, 43%, 29%, 71% and 9% in ACTH, LH, FSH, TSH and PRL respectively. 2) Relatively higher incidence of hyporeactive TSH response in TRH test seems to be characteristic in acromegalic patients. 3) Six of 13 acromegalic patients examined on blood PRL level revealed relatively high blood PRL level over 50ng/ml.  相似文献   
92.
A case of small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features is presented. The tumor was encountered in a 32 year old Japanese woman with an initial presentation of palpable tumor in the left lateral region of the thorax. The resected tumor was a partially well encapsulated whitish medullary one and consisted of small round and spindle tumor cells, together with so-called rhabdoid cells in the small round cell area. Although pseudorosettes were often observed, true rosette formation could not be detected anywhere. Ultrastructurally, despite a histologic variety of tumor cells, most tumor cells possessed numerous mitochondria, some of which occasionally contained abnormal filamentous or crystalloid structures. Various amounts of microfilaments were present in most tumor cells and microtubules were present in a few. A minority of small round cells possessed a small number of neurosecretory granules, especially in short cytoplasmic processes. A positive immunoreaction for neuron specific enolase was found by immunohistochemical examination in several small round tumor cells and for neurofilaments in lesser numbers. Despite the lack of S-100 protein, MB2 was detected in both small round and spindle cells. On the basis of these findings, the tumor of the present case corresponds to malignant peripheral nerve sheath tumor with neuronal differentiation and oncocytic features.  相似文献   
93.
94.
The electrochemical reduction of CO2 on a Cu electrode was investigated in aqueous NaHCO3 solution, at low temperature. A divided H-type cell was employed, the catholyte was 0.65 mol dm−3 NaHCO3 aqueous solution and the anolyte was 1.1 mol dm−3 KHCO3 aqueous solution. The temperature during the electrolysis of CO2 was decreased stepwise to 271 K. Methane and formic acid were obtained as the main products. The maximum Faradaic efficiency of methane was 46% at −2.0 V and 271 K. The efficiency of hydrogen formation, a competing reaction of CO2 reduction, was significantly depressed with decreasing temperature. Based on the results of this work, the proposed electrochemical method appears to be a viable means for removing CO2 from the atmosphere and converting it into more valuable chemicals. The synthesis of methane by the electrochemical method might be of practical interest for fuel production and the storage of solar energy.  相似文献   
95.
The transmembrane nature of the receptor-like protein tyrosine phosphatases (PTPases) suggests that they transduce as yet unidentified extracellular signals to intracellular events via a phosphotyrosyl-protein dephosphorylation step, although little is known of their regulation and cellular activities. Structure/function studies of PTP alpha demonstrate that both catalytic domains are required for full enzymatic efficiency and that interdomain interactions may modulate PTP alpha activity and specificity. Overexpression of PTP alpha results in cell transformation and tumorigenesis, likely as a consequence of the ability of PTP alpha to dephosphorylate and activate the c-src tyrosine kinase. This suggests a role for PTP alpha in normal cell proliferation. PTP alpha is so far unique among the PTPases in terms of its oncogenic potential, and overexpression or deregulation of PTP alpha may be involved in the genesis, progression or maintenance of certain tumor states.  相似文献   
96.
Twenty-three patients with epileptic type moyamoya disease are reviewed among 200 moyamoya disease patients. Ten boys and 13 girls aged 5 months to 12 years were followed over 6 months to 17.3 years. Six had generalized seizure and 17 had focal seizure. Operations were performed within 1 year in eight patients, within 1-3 years in five, and more than 3 years after onset in 10. Nineteen patients improved and suffered no seizure without receiving antiepileptic drugs, but four patients developed true epilepsy and three of these suffered cerebral infarction. Multivariate analyses showed that toddlers aged less than 1 year and mild or severe abnormal computed tomographic (CT) findings correlated with a bad outcome. This study showed that epileptic type moyamoya disease has the same clinical features as transient ischemic attack or infarction type. Age under 1 year and CT abnormalities indicate a poor prognosis and necessity for early reconstructive surgery.  相似文献   
97.
Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought.  相似文献   
98.
99.
The cubic-tetragonal martensitic transition of V3Si and its precursor have been investigated in the temperature range from 13 K to 80 K using a 1 MV electron microscope with a double-tilting cold stage. Below the transition temperature Tm = 19 K, fine twin lamellae appear parallel to {110} plane traces, being connected continuously with mottled striations having the same orientation. Fine striations along {110} traces or so-called tweeds are observed below 50 K at the precursor of the structural phase transition. The image contrast of mottled striations and tweed patterns is attributed to the presence of lattice distortion owing to the softening of the shear modulus. Reversible changes of the patterns recorded with a TV-VTR system during cooling and heating processes were discussed briefly. This paper is based on a presentation made in the symposium “Pretransformation Behavior Related to Displacive Transformations in Alloys” presented at the 1986 annual AIME meeting in New Orleans, March 2–6, 1986. under the auspices of the ASM-MSD Structures Committee.  相似文献   
100.
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