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The duration of voluntary holding of external breathing (VHEB) on inspiration or expiration was measured in 300 18- to 22-year-old subjects of both sexes at rest and during bicycle ergometer exercise, in a sitting position or in the float posture, on land or immersed in water. The length of expiratory VHEB was found to depend on the residual lung volume, whereas inspiratory VHEB correlated with the functional residual lung capacity. Physical exercise increased the oxygen uptake and accelerated the consumption of lung oxygen reserves available on inspiration or expiration and decreased the duration of VHEB. Special formulas were proposed for calculating the theoretical length of VHEB and for its comparing the result with corresponding experimental values, as well as for determination of the lung volumes and oxygen consumption.  相似文献   

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Ventilatory function declines during the early stages of irradiation for bronchial carcinoma. This decline is potentially dangerous if the tumour narrows the trachea or both main bronchi. The protective effect of preliminary treatment with prednisolone or mustine before irradiation was studied in 88 patients by serial estimations of forced expiratory volume and forced vital capacity. Twenty-three patients received prednisolone by mouth, 24 had mustine intravenously, and 41 had no preliminary treatment. Both prednisolone and mustine prevented a significant decline in ventilatory function due to tumour swelling, prednisolone being marginally superior. It is concluded that all patients at risk should be treated with oral prednisolone, 20 mg daily, for one day before and two days after the first fraction of irradiation.  相似文献   

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超低能离子束注入后番茄的生物学效应   总被引:8,自引:0,他引:8  
利用超低能氮离子束注入河南四号番茄干种子,观察发芽率及田间农艺性状的表现,采用聚丙稀酰胺凝胶电泳的方法分析M0代、M1代幼苗期过氧化物酶和酯酶同工酶的变化。结果表明,不同剂量间芽率的变化幅度较小,其总趋势是先升高后略微下降,呈现“马鞍型”曲线。但在幼苗期群体内某些单株的子叶呈镰刀型,其刺激效应十分明显,并且在7×1017N /cm2剂量下M1材料中发现5株突出的变异单株,呈细叶型、长花瓣,株型、果形已发生明显得变异,并且已经稳定遗传到第四代。同工酶分析显示:超低能离子束注入河南四号番茄后不同剂量间POD酶活性有差异,比对照酶活性增强,M1代突变体的POD酶活增强更显著;EST同工酶的活性表现不同,M1-1酶谱的带数比对照少四条,M1-2比对照多出四条,且主酶带比对照颜色深。由此认为,超低能离子注入技术对番茄的遗传改良有一定效果。  相似文献   

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不同波长激光辐照花生种子的生物学效应   总被引:9,自引:0,他引:9  
本实验考察了K+r、Ar+、Nd:YAG、HeNe和LD等不同波长的激光辐照对花生种子产生的生物学效应。结果显示,适当剂量不同波长的激光辐照都能促进花生种子生长。在辐照剂量为0.128w/cm2×180s的条件下,较短波长激光对花生幼苗的促进作用比长波长激光显著;在辐照剂量为1.28w/cm2×18s的条件下,短波长激光对花生种子的萌发及胚的生长有抑制作用,而长波长激光有促进效应。在相同辐照剂量条件下,不同功率密度与时间的组合其辐照效果不同。1.28w/cm2功率密度的Nd:YAG(532nm)激光脉冲输出辐照对花生种子的生长产生显著的抑制作用。实验结果提示,要得到相同的辐照效果,长波长激光与短波长激光相比,必须提高辐照功率密度或加大辐照输出剂量。  相似文献   

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A kill of 99.99% was obtained in cell suspensions of Escherichia coli and Streptococcus faecalis by incubation with hydrogen peroxide 1.0% (w/v) for 75 and 180 min respectively. The same kill was produced by 30 s irradiation with ultraviolet (u.v.) light in the presence of hydrogen peroxide 1.0% (w/v). This simultaneous treatment with u.v. and hydrogen peroxide produced a synergistic kill at least 30-fold greater than that produced by irradiation of cell suspensions of Esch. coli with or without subsequent incubation with hydrogen peroxide.  相似文献   

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Ultra-violet (u.v.) light irradiation of spores of Bacillus subtilis in the presence of hydrogen peroxide produced a rapid kill which was up to 2000-fold greater than that produced by irradiation alone. A kill of 99–99% was produced by 30s u.v. irradiation of spores of 6 strains of Bacillus and Clostridium in the presence of hydrogen peroxide 1.0 g/100 ml but with the more resistant spores of 9 further strains, irradiation in the presence of hydrogen peroxide 2–5 g/100 ml followed by mild heating was required.  相似文献   

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Background

Pulmonary edema plays a pivotal role in the pathophysiology of respiratory syncytial virus (RSV)-induced respiratory failure. In this study we determined whether treatment with TIP (AP301), a synthetic cyclic peptide that mimics the lectin-like domain of human TNF, decreases pulmonary edema in a mouse model of severe human RSV infection. TIP is currently undergoing clinical trials as a therapy for pulmonary permeability edema and has been shown to decrease pulmonary edema in different lung injury models.

Methods

C57BL/6 mice were infected with pneumonia virus of mice (PVM) and received TIP or saline (control group) by intratracheal instillation on day five (early administration) or day seven (late administration) after infection. In a separate set of experiments the effect of multiple dose administration of TIP versus saline was tested. Pulmonary edema was determined by the lung wet-to-dry (W/D) weight ratio and was assessed at different time-points after the administration of TIP. Secondary outcomes included clinical scores and lung cellular response.

Results

TIP did not have an effect on pulmonary edema in different dose regimens at different time points during PVM infection. In addition, TIP administration did not affect clinical severity scores or lung cellular response.

Conclusion

In this murine model of severe RSV infection TIP did not affect pulmonary edema nor course of disease.  相似文献   

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多聚腺苷酸结合蛋白(poly (A) binding protein,PABP)家族通常被认为是mRNA poly (A)尾的一种保护屏障.其中细胞质多聚腺苷酸结合蛋白1 (cytoplasmic poly (A) binding protein-1,PABPC1)在高亲和力作用下能够与mRNA中富含腺苷酸的序列结合,在基因转录后调控中发挥着重要作用.同时PABPC1还参与mRNA的许多代谢通路,包括腺苷酸多聚化/脱腺苷酸化、m RNA转运、m RNA翻译、降解及mircoRNA相关调控.近年来关于PABPC1与生殖细胞的发育、心肌肥大和肿瘤的发生发展的报道屡见不鲜,可见PABPC1与细胞的生长发育有密切联系.本文将主要介绍PABPC1的结构、表达调控、功能及其生物学作用.  相似文献   

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胡明玉  李倩  章宏伟 《生物磁学》2011,(7):1346-1348
目的:探讨红光照射对难治性创面的创缘组织中血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)的表达及治疗难治性创面的临床效果。方法:收集2008年6月-2010年12月因难治性创面入住笔者单位治疗的40例患者,按治疗方法分为红光照射治疗组20例和常规治疗组20例。常规治疗组患者创面以0.5%碘伏与水胶体敷料换药。治疗组在常规治疗的基础上加用红光照射。于治疗后第7天、14天、21天切取创缘组织,研究红光照射对创缘组织中VEGF的影响,并比较两组患者的创面愈合率和愈合时间。结果:临床实验中,治疗组创缘组织中的VEGF含量明显高于对照组(P〈0.01);治疗组创面愈合率明显高于对照组(P〈0.01);治疗组的愈合时间低于对照组(P〈0.05)。结论:红光照射能显著提高创缘组织中VEGF含量,减少创面愈合时间,促进愈合。  相似文献   

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红光促进难治性创面愈合的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:探讨红光照射对难治性创面的创缘组织中血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)的表达及治疗难治性创面的临床效果。方法:收集2008年6月-2010年12月因难治性创面入住笔者单位治疗的40例患者,按治疗方法分为红光照射治疗组20例和常规治疗组20例。常规治疗组患者创面以0.5%碘伏与水胶体敷料换药。治疗组在常规治疗的基础上加用红光照射。于治疗后第7天、14天、21天切取创缘组织,研究红光照射对创缘组织中VEGF的影响,并比较两组患者的创面愈合率和愈合时间。结果:临床实验中,治疗组创缘组织中的VEGF含量明显高于对照组(P<0.01);治疗组创面愈合率明显高于对照组(P<0.01);治疗组的愈合时间低于对照组(P<0.05)。结论:红光照射能显著提高创缘组织中VEGF含量,减少创面愈合时间,促进愈合。  相似文献   

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半导体激光辐照对花生种子活力的影响   总被引:1,自引:0,他引:1  
欧琳  庄伟建 《激光生物学报》1997,6(4):1220-1224
采用350nw,810nm近红外光导体激光辐照花生干种子,经激光辐照后,种子胚根生长速度加快,胚根长度增加,侧根数目增加,种子出苗率提高。幼苗苗鲜重与根鲜重指标均高于对照组。实验证明,适当剂量的近红外半导体激光辐照可提高花生种子活力,促进幼苗生长。  相似文献   

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本文通过对肿瘤患者E玫瑰花环及淋巴细胞转化率的检测,探讨自血光化学放射敏疗法对机体免疫功能的影响。结果表明:单纯放疗组E玫瑰花环形成及淋巴细胞转化率较放职前明显下降,而自血光化学放疗增敏组治疗前后上述免疫功能无明显改变,表明自血光化学疗法对肿瘤放疗患者的细胞免疫功能具有保护作用。  相似文献   

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Background

Pulmonary hypertension (PH) is a progressive disorder characterized by an increase in pulmonary artery pressure and structural changes in the pulmonary vasculature. Several observations indicate that growth factors play a key role in PH by modulating pulmonary artery smooth muscle cell (PA-SMC) function. In rats, established monocrotaline-induced PH (MCT-PH) can be reversed by blocking platelet-derived growth factor receptors (PDGF-R), epidermal growth factor receptors (EGF-R), or fibroblast growth factor receptors (FGF-R). All these receptors belong to the receptor tyrosine kinase (RTK) family.

Methods and Results

We evaluated whether RTK blockade by the nonspecific growth factor inhibitor, suramin, reversed advanced MCT-PH in rats via its effects on growth-factor signaling pathways. We found that suramin inhibited RTK and ERK1/2 phosphorylation in cultured human PA-SMCs. Suramin inhibited PA-SMC proliferation induced by serum, PDGF, FGF2, or EGF in vitro and ex vivo. Treatment with suramin from day 1 to day 21 after monocrotaline injection attenuated PH development, as shown by lower values for pulmonary artery pressure, right ventricular hypertrophy, and distal vessel muscularization on day 21 compared to control rats. Treatment with suramin from day 21 to day 42 after monocrotaline injection reversed established PH, thereby normalizing the pulmonary artery pressure values and vessel structure. Suramin treatment suppressed PA-SMC proliferation and attenuated both the inflammatory response and the deposition of collagen.

Conclusions

RTK blockade by suramin can prevent MCT-PH and reverse established MCT-PH in rats. This study suggests that an anti-RTK strategy that targets multiple RTKs could be useful in the treatment of pulmonary hypertension.  相似文献   

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Dark-grown pea seedlings (Pisum sativum L.) were irradiated for a short period each day with low intensity red light (662 nm), red light immediately followed by far red light (730 nm), or far red light alone. Other plants were transferred to a white light regime (14 hours light/10 hours dark). There was no change in the amount of RNA in the tissue on a fresh weight basis after the various treatments. However, compared with dark-grown seedlings, those plants irradiated with red light showed an increase in the net RNA content per stem apex. In addition there was a two- to three-fold increase in ribosomal RNA of the etioplasts relative to the total ribosomal RNA. These increases were comparable to those found in plants grown in the white light regime. The changes were much smaller if the dark-grown plants were irradiated either with red light followed by far red light, or with far red light alone. Thus continuous light is not essential for the production of ribosomal RNA in plastids, and the levels of ribosomal RNA found in chloroplasts can also be attained in etioplasts of pea leaves in the dark provided the leaf phytochrome is maintained in its active form.  相似文献   

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