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61.
摘要 目的:探讨盐酸艾司洛尔联合右美托咪定对肺癌患者应激反应和辅助性T细胞1(Th1)/Th2型细胞因子的影响。方法:选取武汉科技大学附属天佑医院2020年6月~2022年3月期间收治的肺癌根治术患者112例。按照随机数字表法将患者分为对照组(n=56,常规麻醉联合盐酸右美托咪定注射液)和研究组(n=56,对照组基础上联合盐酸艾司洛尔注射液)。对比两组苏醒质量、肺功能指标、应激反应指标、Th1/Th2型细胞因子和术后肺部并发症发生率变化情况。结果:研究组的呼吸恢复时间、定向力恢复时间、拔管时间短于对照组(P<0.05)。研究组术后肺部并发症发生率低于对照组(P<0.05)。研究组术毕动态肺顺应性(Cdyn)高于对照组,平台压(Pplat)、气道峰压(Ppeak)低于对照组(P<0.05)。研究组术毕皮质醇(Cor)、去甲肾上腺素(NE)及肾上腺素(E)低于对照组(P<0.05)。研究组术毕肿瘤坏死因子-α(TNF-α)、白细胞介素-2(IL-2)低于对照组(P<0.05),研究组术毕白细胞介素-10(IL-10)、转化生长因子-β1(TGF-β1)高于对照组(P<0.05)。结论:盐酸艾司洛尔联合右美托咪定用于肺癌根治术中,具有较好的麻醉效果,可有效减轻术中应激反应,调节免疫功能并保护肺功能,还可降低术后肺部并发症发生率。 相似文献
62.
《Animal : an international journal of animal bioscience》2023,17(4):100727
The aim of this study is built in two phases: to quantify the ability of novel milk metabolites to measure between-animal variability in response and recovery profiles to a short-term nutritional challenge, then to derive a resilience index from the relationship between these individual variations. At two different stages of lactation, sixteen lactating dairy goats were exposed to a 2-d underfeeding challenge. The first challenge was in late lactation, and the second was carried out on the same goats early in the following lactation. During the entire experiment period, samples were taken at each milking for milk metabolite measures. For each metabolite, the response profile of each goat was characterised using a piecewise model for describing the dynamic pattern of response and recovery profiles after the challenge relative to the start of the nutritional challenge. Cluster Analysis identified three types of response/recovery profiles per metabolite. Using cluster membership, multiple correspondence analyses (MCAs) were performed to further characterise response profile types across animals and metabolites. This MCA analysis identified three groups of animals. Further, discriminant path analysis was able to separate these groups of multivariate response/recovery profile type based on threshold levels of three milk metabolites: β-hydroxybutyrate, free glucose and uric acid. Further analyses were done to explore the possibility of developing an index of resilience from milk metabolite measures. Different types of performance response to short-term nutritional challenge can be distinguished using multivariate analyses of a panel of milk metabolites. 相似文献
63.
In many organisms, the synthesis of heat shock proteins during heat shock is concomitant with the cessation of at least a portion of normal cellular protein synthesis. Heat shocked barley aleurone layers selectively stop the synthesis and secretion of secretory proteins. Exposure to 40°C causes a disruption of endoplasmic reticulum (ER) lamellae, which we have hypothesized leads to the destabilization of otherwise stable mRNA previously associated with ER‐bound polyribosomes. We report here that this was also observed in wounded carrot ( Daucus carota L.) root parenchyma tissue which synthesizes and secretes cell wall proteins when mechanically wounded. Nondenaturing cationic polyacrylamide gel electrophoresis of radiolabeled proteins indicated that heat shock caused the cessation of the synthesis and secretion of extensin, a hydroxyproline‐rich cell wall glycoprotein. Northern blot analyses indicated that the mRNA levels for both extensin and another cell wall protein (p33) were rapidly diminished during heat shock. Under nonheat shock conditions extensin mRNA had a half‐life of greater than 4 h, but this appeared to be reduced to less than 30 min during heat shock. There was also a concomitant dissociation of ER lamellae in wounded, heat shocked carrot root tissue, as observed by transmission electron microscopy. These observations indicate that this response may be universal among plant secretory tissues. 相似文献
64.
A review of Endo's experimental and theoretical procedures and data indicates that the magnitude of the principal strains in the glabella region of both humans and gorillas are low as compared to other parts of the face. Therefore, his data do not provide support for the hypothesis that the glabella region is a highly stressed region during biting. In addition, increased levels of strain in the supraorbital region are directly related to increased levels of masticatory muscle and reaction forces, and not necessarily to anterior tooth loading as opposed to posterior tooth loading. His data also indicate that the supraorbital region in extant humans cannot be accurately modeled as a beam. These conclusions either differ from those of Endo or are not clearly presented or emphasized throughout any of Endo's papers. Therefore, we suggest that a number of investigators have made unsupported or erroneous conclusions based on Endo's work. This is particularly true for those studies that have emphasized the existence of powerful bending stress in the glabella region during incisor biting in both humans and non-human primates. 相似文献
65.
Douglas L. Mann 《Cytokine & growth factor reviews》1996,7(4):341-354
The ability of myocardium to successfully compensate for, and adapt to, stress ultimately determines whether the heart will decompensate and fail, or whether it will instead maintain preserved function. Despite the importance of the myocardial response to environmental stress, very little is known with respect to the biochemical mechanisms that are responsible for mediating and integrating the stress response in the heart. In the present review we will summarize recent experimental material which suggests that cytokines that are expressed within the myocardium in response to a environment injury, namely tumor necrosis factor-alpha (TNF-α), interleukin-1 (IL-1) and interleukin-6 (IL-6), may play an important role in initiating and integrating homeostatic responses within the heart. However, these ‘stress-activated’ cytokines all have the potential to produce cardiac decompensation when expressed at sufficiently high concentrations. Accordingly, the theme that will emerge from this discussion is that the short-term expression of stress-activated cytokines within the heart may provide the heart with an adaptive response to stress, whereas long-term expression of these molecules may be frankly maladaptive by producing cardiac decompensation. 相似文献
66.
Binding-protein expression is subject to temporal,developmental and stress-induced regulation in terminally differentiated soybean organs 总被引:3,自引:0,他引:3
Andrew Kalinski Daniel L. Rowley Deborah S. Loer Carolyn Foley George Buta Eliot M. Herman 《Planta》1995,195(4):611-621
Binding protein (BiP) is a widely distributed and highly conserved endoplasmic-reticulum luminal protein that has been implicated in cotranslational folding of nascent polypeptides, and in the recognition and disposal of misfolded polypeptides. Analysis of cDNA sequences and genomic blots indicates that soybeans (Glycine max L. Merr.) possess a small gene family encoding BiP. The deduced sequence of BiP is very similar to that of other plant BiPs. We have examined the expression of BiP in several different terminally differentiated soybean organs including leaves, pods and seed cotyledons. Expression of BiP mRNA increases during leaf expansion while levels of BiP protein decrease. Leaf BiP mRNA is subject to temporal control, exhibiting a large difference in expression in a few hours between dusk and night. The expression of BiP mRNA varies in direct correlation with accumulation of seed storage proteins. The hybridization suggests that maturing-seed BiP is likely to be a different isoform from vegetative BiPs. Levels of BiP protein in maturing seeds vary with BiP mRNA. High levels of BiP mRNA are detected after 3 d of seedling growth. Little change in either BiP mRNA or protein levels was detected in maturing soybean pods, although BiP-protein levels decrease in fully mature pods. Persistent wounding of leaves by whiteflies induces massive overexpression of BiP mRNA while only slightly increasing BiP-protein levels. In contrast single-event puncture wounding only slightly induces additional BiP expression above the temporal variations. These observations indicate that BiP is not constitutively expressed in terminally differentiated plant organs. Expression of BiP is highest during the developmental stages of leaves, pods and seeds when their constituent cells are producing seed or vegetative storage proteins, and appears to be subject to complex regulation, including developmental, temporal and wounding.The mention of vendor or product does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over vendors of similar products not mentioned.Abbreviations BiP
binding protein
The sequences reported in this paper have been submitted to Gen-Bank and are identified with the accession numbers BiP-A (U08384), BiP-B (U08383), BiP-C (U08382) and -1,3 glucanase (U08405). 相似文献
67.
Expression of heat shock genes in Clostridium acetobutylicum 总被引:1,自引:0,他引:1
68.
I. Yu. Malyshev E. B. Manukhina V. D. Mikoyan L. N. Kubrina A. F. Vanin 《FEBS letters》1995,370(3):159
Heat shock potentiated the nitric oxide production (EPR assay) in the liver, kidney, heart, spleen, intestine, and brain. The heat shock-induced sharp transient increase in the rate of nitric oxide production preceded the accumulation of heat shock proteins (HSP70) (Western blot analysis) as measured in the heart and liver. In all organs the nitric oxide formation was completely blocked by the NO-synthase inhibitor
(L-NNA). L-NNA also markedly attenuated the heat shock-induced accumulation of HSP70. The results suggests that nitric oxide is involved in the heat shock-induced activation of HSP70 synthesis. 相似文献
69.
Swim Stress Increases the Potency of Glycine at the N-Methyl-d-Aspartate Receptor Complex 总被引:1,自引:0,他引:1
Gabriel Nowak †Anna Redmond †Mairead McNamara ‡ Ian A. Paul 《Journal of neurochemistry》1995,64(2):925-927
Abstract: We have previously demonstrated that chronic administration of antidepressants results in a reduction in the potency of glycine to displace 5,7-[3 H]dichlorokynurenic acid (5,7-[3 H]-DCKA) from the strychnine-insensitive glycine recognition site of the NMDA receptor complex. We now report that exposure of rats to the forced swim test results in a 56% increase in the potency of glycine to displace 5,7-[3 H]DCKA from frontal cortical homogenates. These data are consistent with the hypothesis that the forced swim test, a preclinical screen sensitive to acute administration of antidepressant drugs and NMDA receptor antagonists, also results in adaptation of the NMDA receptor complex. Moreover, these data lend further support to the hypothesis that glutamatergic pathways are involved in the neurobiological response to stress and, potentially, in the pathophysiology of depression. 相似文献
70.
Carol A. Sheppard Peter B. Simpson Alan H. Sharp Frederick C. Nucifora Christopher A. Ross †G. David Lange James T. Russell 《Journal of neurochemistry》1997,68(6):2317-2327
Abstract: We have examined the mechanisms that underlie Ca2+ wave propagation in cultured cortical astrocytes. Norepinephrine evoked Ca2+ waves in astrocytes that began at discrete initiation loci and propagated throughout the cell by regenerative amplification at a number of cellular sites, as shown by very high Ca2+ release rates at these regions. We have hypothesized previously that domains displaying elevated Ca2+ release kinetics in astrocytes may correspond to sites of high inositol 1,4,5-trisphosphate receptor (InsP3 R) density. To examine this possibility, we compared the distribution pattern of endoplasmic reticulum (ER) and InsP3 Rs with Ca2+ release kinetics in subcellular regions during propagation of norepinephrine-evoked waves. 3,3'-Dihexyloxacarbocyanine iodide staining revealed that the ER in astrocytes exists as a meshwork of membranes extending throughout the cells, including fine processes. A specific antibody directed against type 2 InsP3 Rs (InsP3 R2) detected a 260-kDa band in western blotting of astrocyte membranes. Immunocytochemistry using this antibody stained the entire ER system in a punctate, variegated manner. When Ca2+ responses and InsP3 R2 immunofluorescence were compared in the same cell, domains of elevated Ca2+ response kinetics (high amplitude and rapid rate of rise) showed significant positive correlation with high local intensity of InsP3 R2 staining. It appears, therefore, that specializations in the ER responsible for discrete local Ca2+ release sites that support regenerative wave propagation include increased levels of InsP3 R2 expression. 相似文献