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911.
G. S. Yakobson A. R. Antonov G. V. Petrova L. N. Maslova A. L. Markel' 《Bulletin of experimental biology and medicine》1996,121(5):449-451
Endocrine functions were investigated in normotensive (Wistar) and hypertensive (NISAG) rats before and on days 3, 7, and
21 after subcutaneous epinephrine administration. Rats of the NISAG strain are characterized by elevated plasma levels of
aldosterone and thyroxine and lowered plasma levels of immunoreactive insulin, and their endocrine system develops a much
stronger response to a single epinephrine injection than does that of Wistar rats. This is manifested in a still higher aldosterone
level, elevated corticosterone and insulin concentrations, and reduced thyroxine content in the plasma.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 495–498, May, 1996 相似文献
912.
Stolina M Guo J Faggioni R Brown H Senaldi G 《Clinical immunology (Orlando, Fla.)》2003,109(3):347-354
The interaction between receptor activator of nuclear factor-kappaB ligand (RANKL) and RANK has been reported to regulate immunity in addition to bone metabolism. The aim of this study was to determine if osteoprotegerin (OPG), an inhibitor of the RANKL-RANK interaction and possibly a new drug against osteoporosis, would adversely affect immunity. OPG was used to treat mice developing different models of cellular and humoral immune responses and also in vitro in T and B cell assays. In mice, OPG does not affect cell-mediated reactions such as contact hypersensitivity to the hapten oxazolone and liver damage, granuloma formation, and infectious load induced by mycobacterial infection. However, OPG increases humoral reactions such as the production of IgM, IgG, and IgE against the T cell dependent antigen keyhole limpet hemocyanin and the production of IgM against the T cell independent antigen Pneumovax. In vitro, OPG modestly co-stimulates T cells but does not affect the proliferation of B cells. OPG has modest immunoregulatory effects that seem to be confined to the humoral response to specific antigens. 相似文献
913.
S. S. Timoshin N. B. Simon A. P. Baranov 《Bulletin of experimental biology and medicine》1979,88(3):1056-1058
It was shown previously that exposure to stressors led to a decrease in the number of mitoses in the cornea as a result of G2–M delay. The index of labeled nuclei and level of pathological mitoses were unchanged. It is now shown that injection of pyrogenal or contact hypothermia for 1 h to 28–30°C did not cause reactive inhibition to develop in adrenalectomized rats, but led to a significant increase in the level of pathological mitoses in the cornea from 4.3–6.3% in intact and adrenalectomized rats to 10.6–12.5% in adrenalectomized rats exposed to stress. Karyotypic analysis of the bone marrow cells under these conditions revealed a significant increase in the number of aneuploid cells (both hypo- and hyperdiploid).Central Research Laboratory, Khabarovsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 9, pp. 338–341, September, 1979. 相似文献
914.
The distribution of clinical findings in Bechterew's syndrome (ankylosing spondylitis) suggests distinct genetic subgroups 总被引:4,自引:0,他引:4
One hundred and twenty-two consecutive patients hospitalized for ankylosing spondylitis (AS) were reexamined. The frequency of clinical signs and results of tests for associations are presented. Psoriasis was associated with a distal pattern of peripheral arthropathy. Spinal rigidity was predominantly seen in males. Males with phalangeal arthropathy exhibited preserved spinal mobility. This was the case also when HLA B27 positives and patients who did not have psoriasis were considered separately. HLA B27 positive patients in this group had frequently experienced acute anterior uveitis. It seems possible that the disease in such males is the result of combined predisposition to ankylosing spondylitis and psoriatic arthropathy. Hip arthropathy was frequently present in males with spinal rigidity. The associations observed confirm that AS is a heterogenous group of diseases. The term "syndrome" may be suitable for such a heterogenous group, and we prefer the term "Bechterew's syndrome" as the name of this group. When these new findings are added to the previous observations that acute anterior uveitis probably is a clinical, sex-influenced characteristic of HLA B27 positive Bechterew's syndrome, that HLA B27 negative patients with Bechterew's syndrome frequently had psoriasis and were HLA B13 and B17 negative, and that psoriasis was frequent in HLA B27 positive patients as well, we tentatively conclude that different and interacting genetic mechanisms may be involved in the etiology of Bechterew's syndrome. 相似文献
915.
916.
本文测定了31例急性心肌梗塞(AMI)患者血浆甘丙素(GAL)的放免活性,结果显示AMI患者急性期各次血浆GAL水平明显高于对照组,伴高血压、糖尿病和心功能不全者升高更显著,GAL与内皮素(ET)、血糖水平均呈正相关。实验性心肌梗塞大鼠血浆GAL、血清肌酸激酶(CK)、CK同功酶(CK-MB)、丙二醛(MDA)含量亦明显高于对照大鼠。用GAL抗血清治疗心肌梗塞大鼠,减少坏死面积45.4%和缩小了梗塞范围47.1%,亦明显降低了血浆GAL水平,抑制血清CK、CK-MB、MDA活性,提示早期阻断GAL的生物学效应,对防治AMI有重要意义。 相似文献
917.
SARS病毒S1蛋白重组C端片段免疫效果的实验研究 总被引:1,自引:0,他引:1
为获得纯化的重组SARS病毒S1蛋白C端 ,研究其刺激机体产生针对SARS病毒免疫应答的规律和机制 ,将编码SARS病毒S1蛋白C端 311个氨基酸残基的基因克隆 ,并在原核表达系统中表达 ,纯化获得了的重组蛋白。利用SARS患者恢复期的血清 ,对纯化的重组S1蛋白进行血清学分析。结果表明 ,本研究中克隆表达的重组蛋白序列与公布的SARS病毒S1蛋白C端的序列相同 ,其编码的重组蛋白相对分子质量约为 5 90 0 0Mr。SARS患者恢复期的血清均与重组蛋白反应 ,在5 9 0 0 0Mr处形成特异性的反应条带 ,而来自SARS流行前的正常人对照血清则不能与重组蛋白反应。在本研究中获得的重组蛋白可以为研究SARS病毒识别宿主细胞受体的过程及其机制提供条件。 相似文献
918.
Dr. Thomas Menke Petra Niklowitz Bernhard Schlüter Dirk Buschatz Eckardt Trowitzsch Werner Andler 《Somnologie - Schlafforschung und Schlafmedizin》2003,7(2):37-42
Summary Question of the study Respiratory instability as well as tissue damage by free radicals (oxidative stress) have been hypothesized to play a role in cases of sudden and unexpected infant death in the first year of life. The ratio of the oxidized/reduced form of redox compounds in the circulation could be used as a marker of oxidative stress. Therefore, the sleep apnoea rate and redox status of coenzyme Q10 (CoQ10) (percentage of the oxidized form in total CoQ10) were measured in a population of clinically healthy infants in their first year of life in order to study whether a physiological parameter of respiratory instability is related to a biochemical parameter of oxidative stress. Patients and methods Between May and December 1999, 323 infants in the first year of life were referred to a paediatric sleep laboratory. Sleep apnoea rate, periodic breathing and parameters of oxygenation (SaO2 and TcPO2 ) were calculated based on polysomnographic recordings. The CoQ10 redox status was calculated based on high-pressure liquid chromatographic (HPLC) analysis. Results Statistical analysis showed an age-dependent decrease in apnoea rate ( r = – 0.38) and CoQ10 redox status ( r = – 0.40). An increased CoQ10 redox status (median: 16.6 %; range: 7.3 – 29.7 %) was found in infants with high apnoea rates above the 90th percentile of a reference group in comparison with infants with apnoea rates below the 90th percentile of a reference group (median: 10.4 %; range: 5.1 – 20.4 %; P = 0.031). Conclusions These findings may indicate that high apnoea rates are accompanied by increased formation of free radicals in clinically healthy infants in the first year of life. 相似文献
919.
Giordani L Giacomini E Quaranta MG Viora M 《Clinical and experimental immunology》2000,122(3):358-363
We have previously demonstrated that exogenous Nef protein induced activation of normal human T cells up-regulating IL-15 production by monocytes. Since HIV-1 infection results in the early impairment of immune functions we decided to evaluate if Nef is able to modulate the induction of a specific antibody response. Human peripheral blood mononuclear cells from healthy donors were induced in vitro to mount a specific antibody response to the Candida albicans antigen. We show that Nef inhibited, in a dose-dependent manner, the induction of the anti-C. albicans antibody response. The ability of an anti-Nef antibody to prevent such inhibition indicates that the effect was indeed Nef-specific. In the Nef-treated cultures an early increase of IL-15 production was observed and the addition of anti-IL-15 antibody abrogated the Nef-induced inhibitory effect. Moreover the addition of IL-15 to the cultures inhibited, as well as Nef, the induction of the specific antibody response. Thus, our results suggest that Nef may inhibit the induction of a specific antibody response by an early up-regulation of IL-15 production. A better comprehension of this phenomenon may be important for unravelling some aspects of the B cell defects in HIV infection. 相似文献
920.