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971.
High-resolution P-31 MR spectra were obtained in four patients with bone tumors of their distal extremities. In one case the tumor, a Ewing sarcoma of the tibia, was investigated during clinical remission after radiation therapy and chemotherapy. The other three cases - one low-grade chondrosarcoma of the tibial head, one malignant fibrous histiocytoma of the tibia, and one chondroblastoma of the medial femoral condyle - showed clinically active tumor growth, with corresponding increased metabolism as demonstrated by bone scintigraphy. The spectra of the three active tumors indicated a comparably high adenosine triphosphate content, similar to previously published spectra from animal tumors or human tumors implanted into animals. There were also high resonances of inorganic phosphate and low resonances of phosphocreatine; there were definite peaks in the phosphodiester and phosphomonoester regions, indicating the existence of these metabolites in the tumors. Slight but definite changes in the metabolite content were observed in one tumor after chemotherapy. The spectra of the unaffected leg did not show any well-resolved P-31 signals, which is typical for healthy bone. These are the first P-31 MR spectra of human bone tumors measured in patients to our knowledge.  相似文献   
972.
Three analogues of the model peptide of sequence IRGERA corresponding to the COOH-terminal residues 130-135 of histone H3 were synthesized, and their antigenicity, immunogenicity, and resistance to trypsin were compared to those of the natural L-peptide. The three analogues correspond to the D-enantiomer, containing only D-residues, and two retro-peptides containing NH-CO bonds instead of natural peptide bonds. The chirality of each residue was maintained in the retro-peptide and inverted in the retro-inverso-peptide. Antibodies to the four peptide analogues were produced by injecting BALB/c mice with peptides covalently coupled to small unilamellar liposomes containing monophosphoryl lipid A. Each of the four peptide analogues induced IgG antibodies of various subclasses. The IgG3 antibodies reacted similarly with the four analogues, whereas antibodies of the IgG1, IgG2a, and IgG2b isotypes showed strong conformational preferences for certain peptides. The retro-inverso-peptide IRGERA mimicked the structure and antigenic activity of the natural L-peptide but not of the D- and retro-peptides, whereas the retro-peptide IRGERA mimicked the D-peptide but not the L- and retro-inverso-peptides. The equilibrium affinity constants (Ka) of three monoclonal antibodies generated against the L- and D-peptides with respect to the four peptide analogues were measured in a biosensor system. Large differences in Ka values were observed when each monoclonal antibody was tested with respect to the four peptides. The use of retro-inverso-peptides to replace natural L-peptides is likely to find many applications in immunodiagnosis and as potential synthetic vaccines.  相似文献   
973.
K H Shin  P J Muller  P H Geggie 《Cancer》1983,52(11):2040-2043
Superfractionation (SF) radiation therapy is the administration of three fractions per day. We have assessed the effect of SF in a prospective randomized clinical study of malignant astrocytomas from July 1978 to December 1980. Thirty-five patients were randomized to SF (4000 rad in 45 fractions in 3 weeks whole brain and 1000 rad in five fractions in one week local boost). Thirty-four patients were randomized to conventional fractions (3400 rad in 17 fractions whole brain in 3.5 weeks and 1600 rad in eight fractions in 1.5 weeks local boost). Both treatment arms received chemotherapy with CCNU. The 1- and 2-year actuarial survival rate is 54% and 21% for SF group and 32% and 10% for CF group. The other advantages of SF include shorter mean duration of steroid administration and improved performance status following radiation therapy.  相似文献   
974.
The isolated rat heart with ligation of the left coronary artery was used to assess the role of the beta 1- adrenergic receptor-cyclic AMP mechanism in the genesis of vulnerability to ventricular fibrillation in early myocardial ischaemia. Coronary artery ligation was followed after 3 min by a reduction in ventricular fibrillation threshold which reached a minimum at 15 min. This was accompanied by reduction of ATP and phosphocreatine while cyclic AMP was significantly increased in ischaemic myocardium. The dl-, l- and d-isomers of propranolol attenuated the decrease in ventricular fibrillation threshold and the increase in ischaemic myocardial cyclic AMP, without altering the tissue depletion of ATP. Specific beta 1-adrenergic receptor antagonism with atenolol did not prevent either the increase of tissue cyclic AMP or the reduction in ventricular fibrillation threshold and high energy phosphates. These findings suggest that the mechanism whereby vulnerability to fibrillation is increased in very early myocardial ischaemia is linked to changes in cyclic AMP content of ischaemic myocardium and appears independent of depletion of myocardial high energy phosphates.  相似文献   
975.
976.
Approximately 6000,000 routine immunohematological tests have been conducted with Groupamatic GC systems at the National Blood Transfusion Center in Paris. The system is used for determination of the ABO group including A1 and A2 subgrouping; the Rh factors including Du, C, c, E, e, CW;K;Lea; P1; M and N. The detection and identification of irregular alloantibodies is carried out systematically together with detection of the anti-A and anti-B antibodies. Simultaneously, testing for syphilis is done with a cardiolipid antigen. Groupamatic equipment allows 340 samples to be tested per hour and 12 reactions can be carried out simultaneously on each sample. The system is fully automated.  相似文献   
977.
D. P. R. Muller  J. T. Harries    J. K. Lloyd 《Gut》1974,15(12):966-971
The vitamin E status and ease of repletion in groups of children with coeliac disease, intestinal lymphangiectasia, and abetalipoproteinaemia was studied and compared with earlier studies in cystic fibrosis and obstructive jaundice. Each group represents an experimental model in which one of the transport steps involved in the absorption of vitamin E is defective or absent and thus the relative importance of these factors could be determined. Chylomicron formation and an adequate intraluminal concentration of bile salts were found to be the most important factors for the efficient absorption of the vitamin. The results in the five groups of patients have therapeutic implications if it is considered desirable to correct vitamin E deficiency states.  相似文献   
978.
979.
Normal human peripheral blood lymphocytes (PBL) are incapable of eliciting a significant murine cytotoxic T cell (CTL) response either in vivo or in vitro. However, using a primary in vivo and secondary in vitro stimulation with lectin-activated PBL, Thy-l-positive cytotoxic cells were produced. The antigens that these T-cells identified were independent of the serum source employed in the culture medium used for lectin activation. The cells always preferentially lysed cells from the immunizing individual but were also able to lyse target cells from unrelated individuals, regardless of HLA identity or disparity with the immunizing individual, suggesting the presence of both a private (possibly class II antigens) and public specificity. Using the lymphoblasts of different family members as immunogen and targets there was slight preference of the CTL for HLA-identical targets with no apparent difference between the lysis exhibited against semiidentical and nonidentical subjects. Monoclonal antibodies directed against HLA DR or beta 2-microglobulin failed to inhibit the cytotoxicity observed in these experiments. It is suggested that under these circumstances of xenogeneic education, non-MHC-restricted T cells may become cytotoxic, and this model may serve as a useful probe to investigate some of the less-well-defined aspects of the T cell repertoire.  相似文献   
980.
Recently, enucleation of choroidal melanomas tends to be replaced by less radical treatments such as photocoagulation. Use of Ruthenium 106 plaques has proved to be efficient in Germany. Because the Beta rays of Ruthenium 106 have only limited tissue penetration they are used only for tumors of less than 6-7 mm thickness and less than 18 mm2 surface. This report describes 62 cases of choroidal melanomas treated with Ruthenium 106. With a follow-up period of 12 to 48 months, 32 cases had total regression, including 2 cases with metastases. 15 patients required a second procedue and 15 had additional photocoagulation. In 23 of 51 patients the visual acuity remained unchanged. In 26 patients the visual acuity decreased and 2 patients had an improvement. 13 patients with melanomas inside or close to the macular area decreased their visual acuity.  相似文献   
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