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91.
A 63-year-old man with iron loss anaemia and hypercalcaemia was found to have a renal cell carcinoma. Despite the iron-deficient blood and bone marrow picture, the serum ferritin concentration was markedly raised. This was mainly due to a “basic isoferritin”. The serum parathormone concentration was normal. The serum ferritin and calcium concentrations returned to normal after the tumour was removed. We propose that the renal cell carcinoma cells in this patient secreted the basic isoferritin as well as humoral factor(s) responsible for hypercalcaemia.  相似文献   
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The authors demonstrate that it is possible to obtain highly T1-weighted images of the abdomen using a suspended respiration partial saturation (SRPS) method in a breath-holding interval. T2*-weighted images, which reflect tissue T2 as well as variations in the static magnetic field, can also be rapidly obtained. The authors studied five healthy subjects and 19 patients with a variety of liver abnormalities, including benign and malignant hepatic neoplasms, fatty liver infiltration, ascites, and hematoma. On T1-weighted multisection acquisitions, the entire liver can be screened for mass lesions in a single 20-second breath-holding interval. Phase-contrast SRPS images are sensitive to fatty infiltration of the liver. SRPS images are more sensitive to variations in magnetic susceptibility than spin-echo images are, which has been proved to be of value in the detection of hemorrhage. With continued pulse sequence development and clinical study, this method has the potential to become the method of choice for evaluation of the upper abdomen.  相似文献   
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1. The contribution of various excitatory amino acid (EAA) receptors (NMDA, AMPA/kainate and metabotropic) in the brain to the development of morphine dependence was examined. This was performed by measuring the severity of the precipitated withdrawal syndrome following chronic subcutaneous (s.c.) morphine and intracerebroventricular (i.c.v.) EAA antagonist treatment. 2. Continuous subcutaneous (s.c.) treatment with morphine sulphate (36.65 mumol day-1) produced an intense and reliable naloxone-precipitated withdrawal syndrome. 3. Chronic i.c.v. treatment with antagonists selective for metabotropic and NMDA receptors, but not AMPA/kainate receptors, significantly attenuated abstinence symptoms. Conversely, EAA antagonists had very little effect on non-withdrawal behaviours. 4. These results suggest that, as well as changes elicited by activation of NMDA receptors, metabotropic receptors and intracellular changes in the phosphatidylinositol (PI) second-messenger system or the cyclic adenosine 3',5'-monophosphate (cAMP) second messenger system, to which EAA metabotropic receptors are linked, may be involved in the development of opioid dependence with chronic morphine treatment.  相似文献   
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Airways and lung: correlation of CT with fiberoptic bronchoscopy   总被引:7,自引:0,他引:7  
Naidich  DP; Harkin  TJ 《Radiology》1995,197(1):1
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Boron neutron capture therapy of a murine melanoma   总被引:2,自引:0,他引:2  
Boron neutron capture therapy has been carried out on BALB/c mice carrying the Harding-Passey melanoma s.c. on the thigh. p-Boronophenylalanine (BPA), a boronated analogue of natural melanin precursors, was used to target boron selectively to melanoma. BPA was administered to the mice either via i.p. injection or p.o. by intubation. 10B concentrations in tumor ranged from 15 to 40 ppm depending on the route and timing of administration. Irradiations with a predominantly thermal neutron beam were performed at the Brookhaven Medical Research Reactor. In the absence of BPA, only transient tumor growth delays were observed at low neutron fluences. At 5 x 10(16) n/m2, 4 of 22 tumors irradiated in the absence of BPA underwent long-term tumor growth control; after p.o. administration of BPA (40 ppm 10B in the tumor), the fraction of tumors controlled increased to 11 of 19. The average dose to the tumor in the latter group was 17.8 Gy, of which 14.8 Gy were due to the 10B neutron capture reaction. The biological effectiveness of the absorbed dose from the neutron capture reaction, at the 50% tumor control level, was found to be twice that of 100 kVp X-rays.  相似文献   
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