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991.
Because yoga practitioners think they are benefiting from their breath training we hypothesized that yoga respiration training (YRT) could modify the respiratory sensation. Yoga respiration (YR) ("ujjai") consisted of very slow, deep breaths (2-3 min(-1)) with sustained breath-hold after each inspiration and expiration. At inclusion in the study and after a 2-month YRT program, we determined in healthy subjects their eupneic ventilatory pattern and their capacity to discriminate external inspiratory resistive loads (respiratory sensation), digital tactile mechanical pressures (somesthetic sensation) and sound-pressure stimulations (auditory sensation). Data were compared to a gender-, age-, and weight-matched control group of healthy subjects who did not undergo the YRT program but were explored at the same epochs. After the 2-month YRT program, the respiratory sensation increased. Thus, both the exponent of the Steven's power law (Psi=kPhin) and the slope of the linear-linear plot between Psi and mouth pressure (Pm) were significantly higher, and the intercept with ordinate axis of the Psi versus Pm relationship was lower. After YRT, the peak Pm developed against inspiratory loads was significantly lower, reducing the load-induced activation of respiratory afferents. YRT induced long-lasting modifications of the ventilatory pattern with a significant lengthening of expiratory duration and a modest tidal volume increase. No significant changes in somesthetic and auditory sensations were noted. In the control group, the respiratory sensation was not modified during a 15-min period of yoga respiration, despite the peak Pm changes in response to added loads were then significantly reduced. These data suggest that training to yoga respiration selectively increases the respiratory sensation, perhaps through its persistent conditioning of the breathing pattern. 相似文献
992.
Transcriptome analysis in blastocyst hatching by cDNA microarray 总被引:1,自引:0,他引:1
Chen HW Chen JJ Yu SL Li HN Yang PC Su CM Au HK Chang CW Chien LW Chen CS Tzeng CR 《Human reproduction (Oxford, England)》2005,20(9):2492-2501
BACKGROUND: Hatching is an important process for early embryo development, differentiation and implantation. However, little is known about its regulatory mechanisms. By integrating the technologies of RNA amplification and cDNA microarrays, it has become possible to study the gene expression profile at this critical stage. METHODS: Pre-hatched and hatched ICR mouse embryos (25 blastocysts in each group were used in the triplicate experiments) were collected for RNA extraction, amplification, and microarray analysis (the mouse cDNA microarray, 6144 genes, including expressed sequence tags). RESULTS: According to cDNA microarray data, we have identified 85 genes that were expressed at a higher level in hatched blastocyst than in pre-hatched blastocysts. In this study, 47 hatching-related candidate genes were verified via re-sequencing. Some of these genes have been selected and confirmed by real-time quantitative RT-PCR. These hatching-specific genes were also expressed at a lower level in the delayed growth embryos (morula or blastocyst without hatching at day 6 post hCG). These genes included: cell adhesion and migration molecules [E-cadherin, neuronal cell adhesion molecule (NCAM), lectin, galactose binding, soluble 7 (Lgals7), vanin 3 and biglycan], epigenetic regulators (Dnmt1, and SIN3 yeast homolog A), stress response regulators (heme oxygenase 1) and immunoresponse regulators [interleukin (IL)-2-inducible T-cell kinase, IL-4R, interferon-gamma receptor 2, and neurotrophin]. The immunostaining of E-cadherin and NCAM showed strong and specific localization in hatched blastocyst. CONCLUSIONS: This work provides important information for studying the mechanisms of blastocyst hatching and implantation. These hatching-specific genes may have potential as new drug targets for controlling fertility. 相似文献
993.
Talayev VY Zaichenko IY Babaykina ON Lomunova MA Talayeva EB Nikonova MF 《Clinical and experimental immunology》2005,141(3):440-448
The effects of dexamethasone phosphate and interleukin‐7 upon the proliferation of T‐cells and the production of interferon‐γ in the newborn's cord blood mononuclear cell cultures were studied. The capability of dexamethasone to enhance T‐cell proliferation induced by anti‐CD3 with interleukin‐7 in some newborn cord blood mononuclear cell cultures was identified. Dexamethasone suppressed production of interferon‐γ in 68‐h cell cultures stimulated with anti‐CD3 both in the presence of interleukin‐7 and without it. However, a 68‐h cultivation of newborn blood cells with dexamethasone, anti‐CD3 and interleukin‐7 resulted in the accumulation of T‐lymphocytes capable of producing interferon‐γ after restimulation. As a result of it the amount of interferon‐γ producing CD7+ T‐cells and the concentration of interferon‐γ in cultural supernatants were maximal in the cell cultures incubated with anti‐CD3, interleukin‐7 and dexamethasone during the first 68 h and subsequently restimulated with phorbol 12‐myristate 13‐acetate and ionomycin. The stimulation of neonatal or adult blood cells by dexamethasone, anti‐CD3 and interleukine‐7 also causes a decrease in the number of naïve T‐cells and central memory cells and an increase in the number of effector memory CD7+CD45RA+CD62L– cells in cultures. It is possible that these effects are caused by the influence of dexamethasone on IL‐7 receptor expression: it is known that IL‐7 receptor alpha‐chain gene is a glucocorticoid‐inducible gene. 相似文献
994.
DNA错配修复基因甲基化在肝细胞癌发生发展中的作用 总被引:5,自引:1,他引:5
目的探讨DNA错配修复基因(MMR)hMLH1,hMSH2和hMSH3甲基化在肝细胞癌(HCC)发生发展中的作用。方法采用甲基化特异性聚合酶链反应(MSP)法对38例新鲜HCC组织,相应非肿瘤肝组织,2例正常的捐肝组织及6种肝癌细胞系的hMLH1,hMSH2和hMSH3基因启动子CpG岛甲基化进行检测;培养6种肝癌细胞系,MSP法检测加入5-aza-2‘-deoxycytidine前后hMSH2基因在HCC中的甲基化状态改变;逆转录.聚合酶链反应(RT-PCR)方法检测加入5-aza-2’-deoxycytidine前后hMSH2在肝癌细胞株中的mRNA表达改变。结果HCC标本中13.2%(5/38)发生了hMLH1启动子甲基化,68.4%(26/38)发生了hMSH2启动子甲基化;相应的非肿瘤肝组织中hMLH1,hMSH2启动子甲基化阳性率分别为2.6%(1/38),55.3%(21/38);2例正常肝组织中未发现甲基化;6株肝癌细胞系中有5株发生了hMSH2启动子甲基化,而未发现有MLH1启动子甲基化。所有标本中均未发现有hMSH3启动子甲基化。5-aza-2‘-deoxycytidine处理细胞株后,可部分或完全逆转hMSH2启动子甲基化,各细胞株的mRNA均有不同程度的表达增加。结论hMSH3基因启动子CpG岛甲基化与HCC的发生发展关系不大。hMSH2基因甲基化与mRNA表达密切相关,是基因表达调节的一种重要方式。hMLH1和hMSH2基因启动子CpG岛的高甲基化在HCC中是一个常见的基因改变,DNA错配修复基因尤其是hMSH2基因启动子甲基化在HCC的发生中起了重要作用,是早期事件,其可能为临床诊断HCC提供新的检测指标。 相似文献
995.
This study analyzed the expression of anti-islet autoantibodies and HLA-DR and -DQ genotypes in Korean children with type 1 diabetes mellitus (T1DM). The positivity of the anti-ICA512, anti-GAD65, and anti-insulin autoantibodies in the newly onset T1DM patients (n = 15) was 66.7%, 86.7%, and 46.7%, respectively, and all of them had one or more of the autoantibodies. HLA analysis showed higher frequencies of HLA-DRB1*0301, *0405, *09012 and -DQB1*0201, *0401, *03032 alleles in T1DM patients compared to controls (P(c) < 0.05). Because HLA-DQB1*0401, *03032 alleles carry aspartic acid at position 57 of DQB, susceptibility to T1DM in Korean children was not related to the presence of aspartic acid at position 57 of DQB1 locus. We suggest this unique HLA-DR, -DQ allele distribution might be an important factor for the low incidence of T1DM in Korea, and the combined anti-islet autoantibody assays could be valuable screening markers for the early detection of T1DM in Korea. 相似文献
996.
Yu. V. Natochin L. V. Reznik V. K. Brovtsyn V. B. Ivanov E. M. Myazina P. A. Chel'tsov E. I. Shakhmatova 《Bulletin of experimental biology and medicine》1989,108(1):965-966
Laboratory of Evolution of the Kidney and Water and Salt Metabolism, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR, I. P. Ashmarin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 7, pp. 52–54, July, 1989. 相似文献
997.
998.
999.
穿戴式呼吸感应体积描记用于睡眠呼吸事件检测 总被引:2,自引:0,他引:2
可穿戴式呼吸感应体积描记(背心式RIP)系统是我们根据呼吸感应体积描记技术的基本原理研发的一种可穿戴、低负荷的呼吸监测系统.在实现通气量无创测量的基础上,我们将该系统用于睡眠期呼吸事件检测,将该系统与多导睡眠图仪(PSG)对9例疑似睡眠呼吸暂停低通气综合症(SAHS)病人和7名健康男性志愿者进行同步对照检测与分析.通过对比实验,根据背心式RIP系统发生呼吸事件的特征性变化,提出了背心式RIP系统判别呼吸事件的规则.依据该规则,所有经背心式RIP系统诊断为SAHS患者的结果与PSG的诊断结果完全一致,背心式RIP系统检测呼吸事件的敏感性为97.8%,特异性为95.8%,实验结果表明背心式RIP系统能够可靠地检测出睡眠呼吸事件.由于其低生理、心理负荷特性,不需要佩带口鼻气流传感器,可用于家庭环境下、自然睡眠过程的睡眠呼吸紊乱性疾病的诊断. 相似文献
1000.