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51.
Malyak Mark Smith Michael F. Abel Ashley A. Arend William P. 《Journal of clinical immunology》1994,14(1):20-30
Journal of Clinical Immunology - The objective of this study was to characterize interleukin-1 receptor antagonist (IL-1ra) and interleukin-1β (IL-1β) production by human peripheral blood... 相似文献
52.
53.
Purnomo Suryantoro Yasuhiro Takeshima Alimsardjono Haryanto Masafumi Matsuo 《Journal of human genetics》1995,40(2):195-201
Summary Hemoglobin (Hb) M-Saskatoon, a variant of methemoglobin, is characterized by mild hemolysis. It is caused by the substitution of a histidine by a tyrosine at the 63rd amino acid residue of the -globin chain. Amplification and sequence analysis of genomic -globin DNA from an Indonesian boy diagnosed as having the more severe disease thalasemia demonstrated the presence of a C to T transition at nucleotide 473 in one of the two -blogin genes resulting in a histidine to tyrosine substitution at 63rd residue. This amino acid change matched with that reported in Hb M-Saskatoon. This nucleotide change abolished a recognition site for the restriction endonucleaseNlaIII.NalIII digestion of the corresponding -globin DNA amplified from the patient's parents indicated that the mutation was inherited through from his mother. This result shows that the world-wide distribution of Hb M-Saskatoon extends to Indonesia, where it was not previously identified. Possible causes of the unusually severe symptoms observed in the case are discussed. 相似文献
54.
Nakamura Tetsuya; Sekar M. Chandra; Kubagawa Hiromi; Cooper Max D. 《International immunology》1993,5(10):1309-1315
Ig and Igß heterodimers are non-covalently associatedwith Ig to compose the antigen receptor complexes on B cells.The demonstration that different sets of tyrosine kinases bindto the cytoplasmic tails of Ig and Igß suggests thatIg and Igß may activate distinct second messengerpathways. In this study, we examined the effects of mAbs againstan exposed epitope of human Igß on pre-B and B celltriggering. Cross-linkage of Igß on B cells leadsto activation of tyrosine kinases, hydrolysis of phosphatidylinositides,and elevation of intracellular Ca2+, effects qualitatively identicalto those of anti-µ mAbs. Our observations thus indicatethat cross-linking of Igß does not segregate signaltransduction pathways connected with the cytoplasmic talls ofIg and Igß. Ig ligation has been reported to be moreeffective in triggering pre-B than B cells, whereas our resultsindicated that Igß ligation is more efficient in triggeringB than pre-B cells. In addition to their activation properties,the anti-Igß mAbs effectively modulated B cell receptorcomplexes and blocked terminal differentiation of all plasmacell isotypes. The findings support the idea that anti-Igßcould serve as a universal B cell immunosuppressant. 相似文献
55.
L. Gariod T. Binzoni G. Ferretti J. F. Le Bas H. Reutenauer P. Cerretelli 《European journal of applied physiology》1994,68(2):107-110
A procedure is described for standardising the determination of adenosine 5-triphosphate and phosphocreatine concentration ([ATP] and [PC], respectively, in absolute arbitrary units) in human muscle by nuclear magnetic resonance (NMR) spectroscopy. The individual 31phosphorus (21P)-NMR spectra obtained on equal hemispherical tissue volumes (muscle plus skin and fat) were corrected for the thickness of the skin and of the subcutaneous fat. The volumes investigated were standardised using an external reference. The procedure described made possible the comparison of high energy phosphate concentrations among different subjects. It was applied to the assessment of [ATP] and [PC] in four groups of sedentary subjects (children, and adults aged 20–35, 35–50 and over 50 years), and in a group of athletes (volleyball players). The [ATP] and [PC] were not statistically different in the groups investigated. 相似文献
56.
Dennis McGinty Michael Littner Elisabeth Beahm Elizabeth Ruiz-Primo Earl Young James Sowers 《Neurobiology of aging》1983,3(4)
—The incidence of sleep-related breathing disorders (SRBDs) associated with hemoglobin desaturation was determined by nocturnal polygraphic evaluations in 26 healthy men, aged 55–70 years. Sixteen subjects (62%) had abnormal rates of at least 12 episodes per hour of sleep: 8 had occlusive, and 8 had central apnea or hypopnea. During waking ten of 16 SRBD subjects and only one subject without SRBDs exhibited either an elevated nasopharyngeal airway resistance (n=4) or a reduced ventilatory response to hypercapnia (n=4) and/or hypoxia (n=3). However, these abnormalities were not related to the type or severity of SRBDs, and 6 subjects with SRBDs demonstrated no respiratory defect. We conclude that SRBDs have a very high incidence in older males and are not usually secondary to pulmonary cardiac, neurological, or behavioral disorders. Additionally, we hypothesize that abnormalities in ventilatory control or upper airway resistance contribute to SRBDs, but depression of brain stem reticular formation activity during sleep plays a primary role in these disorders. Factors related to both aging and SRBDs are reviewed. These include reduced chemoreceptor responses, altered steroid hormone metabolism, and use and metabolism of hypnotic drugs and alcohol. 相似文献
57.
We report three possibly disease-causing point mutations in one of the inner-ear-specific genes, KIAA1199. We identified an R187C mutation in one family, an R187H mutation in two unrelated families, and an H783Y mutation in one sporadic case of nonsyndromic hearing loss. In situ hybridization indicated that the murine homolog of KIAA1199 mRNA is expressed specifically in Deiters cells in the organ of Corti at postnatal day zero (Pn) P0 before the onset of hearing, but expression in those cells disappears by day P7. The signal of KIAA1199 was also observed in fibrocytes of the spiral ligament and the spiral limbus through to P21, when the murine cochlea matures. Thus, the gene product may be involved in uptake of potassium ions or trophic factors with a particular role in auditory development. Although the R187C and R187H mutations did not appear to affect subcellular localization of the gene product in vitro, the H783Y mutation did present an unusual cytoplasmic distribution pattern that could underlie the molecular mechanism of hearing impairment. Our data bring attention to a novel candidate for hearing loss and indicate that screening of mutations in inner-ear-specific genes is likely to be an efficient approach to finding genetic elements responsible for deafness.Nucleotide sequence data reported herein are available in the DDBJ/EMBL/GenBank databases; for details, see the electronic eatabase section of this article. 相似文献
58.
Sh. K. Kurbanov Ch. R. Alimhodzhaeva 《Bulletin of experimental biology and medicine》1979,87(5):421-423
The enzyme spectrum of pancreatic homogenate was studied in acute experiments on male albino rats during adaptation for 30 days to muscular exertion (forced swimming in water at a temperature of 32±1°C), heat (hyperthermia to 40–41°C), and cold (cooling to 3–4°C) for 3 h. The initial periods of adaptation to these factors (second-twelfth day) were shown to be characterized by a considerable decrease in activity of all the enzymes studied, but later, with adaptation of the animals to these factors, enzyme activity was restored to its original level (18th–24th day), and remained more or less constant until the end of the experiment (30th day). It is suggested that changes in the enzyme spectrum of the pancreas are brought about through the participation of the hypothalamo-hypophyseo-adrenal system in accordance with the principle of the general adaptation syndrome.Laboratory of the Physiology of Digestion and Laboratory of General Physiology, Institute of Physiology, Academy of Sciences of the Uzbek SSR, Tashkent. (Presented by Academician of the Academy of Sciences of the USSR O. G. Gazenko.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 5, pp. 412–414, May, 1979. 相似文献
59.
Summary The a mating pheromones synthesized in three Saccharomyces yeasts (S. cerevisiae, S. kluyveri, and S. exiguus) displayed interspecific actions on the a cells of all three species despite the fact that the amino acid sequences of all three pheromones are different. Mating between species, however, did not occur. The interspecifie pheromone — a cell reaction was not necessarily more effective than the interspecific one. Deceased on March 28, 1987 相似文献
60.
Transient aphasia with lithium toxicity 总被引:1,自引:0,他引:1
J M Krakower 《Psychosomatics》1978,19(1):25-26
A case of transient aphasia in a 48-year-old woman is described. The aphasia occurred when progressive renal insufficiency led to accumulation of lithium to toxic levels, and was associated with well-known clinical findings of lithium toxicity. 相似文献