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1.
Syntheses are described of the endo-Lys8a-vespulakinin 1 and of cyclo-Thr6- and cyclo-Nε-Lys-bradykinin. The linear peptides covering the entire sequences of endo-Lys8a-VSK-1 and Thr6-BK, and the decapeptide containing all residues constituting Lys-BK, with a Arg-Lys peptide bond involving the ε-amino function of lysine, were prepared by the solid-phase procedure based on Fmoc chemistry. Cyclization was carried out by the diphenylphosphorazide method. The amino-terminal octapeptide sequence of vespulakinin 1, Fmoc-Thr(tBu)-Ala-Thr(tBu)-Thr(tBu)-Arg(Pmc)-Arg(Pmc)-Arg(Pmc)-Gly-OH, and its Nα-Boc-[(Gal β)Thr3, (Gal β)Thr4]-analogue, were used to prepare Nα-(1–8 VSK 1)-cyclo-Nε-kallidin and Nα-[(Gal β)Thr3, (Gal β)Thr4, 1–8 VSK 1]-cyclo-Nε-kallidin. Peptides and glycopeptides were characterized by amino-acid analysis, optical rotation, analytical HPLC and FAB-MS. Consistent with previous findings, preliminary pharmacological experiments on smooth muscle preparations showed that the cyclic, or partially cyclic, analogues were significatively less potent than the linear ones. © Munksgaard 1995.  相似文献   
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The association between Coffin-Lowry syndrome and psychosis: a family study   总被引:1,自引:0,他引:1  
ABSTRACT. This paper discusses a family presenting with features of Coffin-Lowry syndrome, namely abnormal facies, skeletal abnormalities and mental handicap. Two of the mildly affected females had psychotic illness with predominant depressive features, and all the severely affected males had profound sensor-ineural deafness.  相似文献   
4.
Monoclonal anti-HLA-DR antibodies inhibited the production of interleukin-2 (IL-2) when added from the initiation of autologous (AMLR) and allogeneic (MLR) mixed lymphocyte reactions, but not 60 h later. The inhibitory activity of the anti-DR sera became apparent 8 h after initiation of the cultures and was maintained throughout the culture period. Interleukin-1 (IL-1) added to cultures carried out in the absence of the anti-DR antibodies significantly enhanced the production of IL-2, whereas addition of IL-1 to anti-DR-treated AMLR and MLR cultures did not restore or increase the synthesis of IL-2. However, when the anti-DR antibodies were added to IL-1-supplemented AMLR and MLR cultures 60 h or more after initiation of the reactions, the antiserum no longer inhibited the capacity of IL-1 to promote the synthesis of IL-2 or the production of IL-2. Finally, resting T cells were unresponsive to IL-1 and did not produce IL-2. It thus seemed that the anti-DR antibodies inhibited production of IL-2 in AMLR and MLR by rendering the IL-2 producer T cells unresponsive to IL-1. Cyclosporin-A, a drug that abrogates activation of T cells by blocking their receptors for HLA-DR antigens, also rendered IL-2-producer T cells unresponsive to IL-1 and abrogated the production of IL-2 in AMLR and MLR. Since resting T cells do not respond to IL-1 or produce IL-2, it is concluded that HLA-DR antigens of the stimulator cells participate in the production of IL-2 in AMLR and MLR by enabling the IL-2 producer T lymphocytes to respond to IL-1. Interleukin-1 promotes the production of IL-2 by IL-1-sensitive T cells. Once the IL-2-producer T cells become sensitive to IL-1, there is no further requirement for HLA-DR antigens.  相似文献   
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The autologous rosette-forming T cells (Tar cells) isolated by means of their ability to form rosettes with autologous erythrocytes were characterized by the use of OKT monoclonal anti-human T-cell subset antibodies and a monoclonal anti-HLA-DR antibody. We found that the phenotype of Tar cells was OKT 3+4+8+Dr as determined by both indirect imnrunofluorescence microscopy and complement-mediated killing of 51Cr-labelled Tar cells. In addition, we found that Tar lymphocytes were able to develop cytotoxicity against allogeneic and trinitrophenol (TNP)-conjugated autologous target cells in the presence of interleukin-2 (IL-2) or serum thymic factor. However, these cells showed little or no cytotoxicity in the absence of interleukin-2 or serum thymic factor. Tar lymphocytes generated helper function for B lymphocytes in the presence of interleukin-2 in both pokeweed mitogen (PWM)- and purified protein derivative (PPD)-stimulated cultures. Nevertheless, non-IL-2-treated Tar cells did not exhibit any helper activity on B cells. Finally, pretreatment of Tar cells with 1000–1500 rad of X ray made these cells unable to develop helper function for B lymphocytes. It is concluded that: (1) OKT 3+4+8+Dr Tar cells are able to generate cytotoxicity against alloantigens and TNP-labelled self structures provided they are stimulated by IL-2 or serum thymic factor; (2) these cells need both to proliferate and to receive help from IL-2 to develop helper cells capable of assisting B-lymphocyte differentiation into plasma cells in both PWM- and PPD-stimulated cultures.  相似文献   
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ABSTRACT. Peroral endoscopic duodenal biopsy was used in the diagnosis and follow-up of forty-nine infants and children with suspected small intestine disease. Their ages ranged between one month and 12 years. Fifty-four upper gastrointestinal endoscopy procedures were performed and 139 biopsies were taken. The mean procedure time was 3.2 min with a range of 1.5–5.5 min. There were no complications. Tissue adequate for histopathologic examination was obtained in all but one of the fifty-four procedures. On the basis of this experience we think that peroral endoscopic duodenal biopsy is faster, safer and as diagnostic as conventional suction biopsy in infants and children. It is also more informative when other diseases of the upper gastrointestinal tract are suspected.  相似文献   
7.
Field electrical stimulation (ES), K+ (50 mM) or ionophore X-537A (0.01 mM) induced tritium release from cat cerebral arteries preincubated with [3H]noradrenaline (NA). Adenosine and AMP (0.5 mM) did not modify tritium release caused by ionophore X-537A, but these agents and ATP (0.5 mM) significantly reduced that elicited by ES and K+; this reduction was antagonized by 1-methyl-3-isobutylxanthine (MIX; 0.05 mM). Inosine (0.5 mM) and the agonist of purinergic A2-receptors, 5'N-ethyl-carboxamide adenosine (NECA; 0.5 mM) had no effect, but the agonist of purinergic A2-receptors L-N6-phenylisopropyl adenosine (L-PIA; 0.1 mM) diminished tritium efflux caused by ES and K+. The adenosine inhibition of ES-induced radioactivity release was not affected by indomethacin (0.05 mM). MIX (0.05 mM) increased tritium release evoked by ES and K+. Agents that increase intracellular cyclic (c)AMP levels, such as dibutyryl cAMP (0.5 mM), the phosphodiesterase inhibitor Ro 20-1724 (0.1 mM), and the activators of adenylate cyclase, forskolin (0.005 mM) and NaF (2 mM) reduced tritium secretion elicited by ES and K+. However, the intracellular increase of cyclic GMP (cGMP) caused by 8-Br-cGMP did not affect this secretion. Dipyridamole (0.05 mM) and the adenosine deaminase inhibitor erythro-9-2-hydroxy-3 nonyl adenosine (EHNA; 0.1 mM) also produced inhibition of tritium secretion elicited by ES and K+. Dipyridamole reduced both the uptake of [3H]NA and [3H]adenosine.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
A 58-year-old woman presented with a new rapidly progressive lesion distal to a stent. This lesion was treated with atherectomy through the stem in order to characterize it pathologically. The aggressive proliferative response discovered suggested that this unusually distal lesion was produced by the trauma of her previous angioplasty .  相似文献   
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The disappearance curves of plasma insulin after intravenous injection of unlabelled pork insulin was studied in nine young female hyperthyroid subjects with Graves' disease and eleven young female normal subjects, who served as controls. Comparison of the curves by analysis of variance did not reveal statistical differences between them (F obtained = 2.8, F F 0.05 = 4.41), implying that there was no significant differences in the transference of injected insulin from plasma to the extra-vascular space between hyper- and euthyroid subjects. The results may suggest that the metabolism of insulin is not appreciably affected in hyperthyroidism.  相似文献   
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