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71.
Hsp70 instability and induction by a pesticide in Folsomia candida   总被引:4,自引:0,他引:4  
The heat shock protein Hsp70 has been shown to be a promising biomarker in aquatic and terrestrial organisms. However, its analysis in the soil insect Folsomia candida (Collembola) poses many problems as the protein is particularly unstable in this species. Western blotting has shown that the principal degradation fragment has a size of 48 kDa. We have developed a Western blot method that avoids the degradation of Hsp70 and was successful in detecting the protein in the springtail F. candida after a heat shock (12, 18 and 24 h at 32°C). In the second part of the study the organisms were exposed to artificial compressed soil contaminated with the dinitrophenol dinoseb (10, 15 and 20 µg g-1 dry weight [DW]). Hsp70 was analysed in pooled samples (40 to 150 collembola according to age) after 1, 2, 3, 4, 5, 6, 7, 11 and 14 days. The only significant induction was observed after 5 days at 20 µg g-1 DW of dinoseb. The induction patterns over time were dissimilar for the different concentrations and a relatively high variability between the replicates was observed. Our results show that we must be cautious when interpreting biomarker results, especially those for Hsp70.  相似文献   
72.
摘要 目的:探讨益心舒胶囊联合替格瑞洛片对不稳定型心绞痛(UAP)患者心功能、血脂和血液流变学的影响。方法:选择2021年4月~2022年5月期间来我院接受治疗的UAP患者108例。根据随机数字表法分为对照组(n=54)和研究组(n=54),在常规治疗的基础上,对照组患者接受替格瑞洛片治疗,研究组患者接受益心舒胶囊联合替格瑞洛片治疗。对比两组疗效、血脂指标、心功能指标、血液流变学指标、临床指标和不良反应。结果:研究组的临床总有效率高于对照组(P<0.05)。治疗后,研究组的左心室收缩末期内径(LVESD)、左心室舒张末期内径(LVEDD)小于对照组,左心室射血分数(LVEF)高于对照组(P<0.05)。治疗后,研究组三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、总胆固醇(TC)低于对照组,高密度脂蛋白胆固醇(HDL-C)高于对照组(P<0.05)。治疗后,研究组的血浆黏度、全血高切黏度、全血低切黏度、纤维蛋白原低于对照组(P<0.05)。治疗后,研究组的心绞痛发作频率、硝酸甘油日消耗量少于对照组,发作持续时间短于对照组(P<0.05)。两组不良反应发生率对比无差异(P>0.05)。结论:UAP患者采用益心舒胶囊联合替格瑞洛片治疗,临床症状明显改善,同时还可改善心功能、血脂和血液流变学。  相似文献   
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74.
Seven (7) males with effort angina and listed for coronary by-pass surgery had muscle biopsies taken from their vastus lateralis muscle for determination of muscle fiber types (%ST), ubiquinone (vitamin Q, UQ), oxidative and fermentative enzyme activities. Graded cycle ergometer exercise to determine intensities corresponding to onset of blood lactate accumulation set to 2.0 nimol × 1–1 (WOSLA) and symptom limited exercise (maximal, WSL) were also undertaken. WOBLA was positively related to %ST (r = 0.92, p < 0.001). %ST was on the other hand inversely related to UQ (r =–0.82, p < 0.05), the heart specific LD subunit LD-H (r =–0.96, p < 0.001), the isozyme LD3 as the fraction of LD (%LD3) (r=–0.93, p < 0.01), and the CK isozyme CKMB as the fraction of CK (%CKMB) (r = –0.88, p < 0.05). It was suggested that muscle UQ depletion in the patients was related to molecular oxygen and free oxygen radical formation. The lack of antioxidants then caused a radical trauma specifically to the ST fiber and their mitochondria. This could be a cause and-effect explanation for the selective ST fiber downregulation in effort angina and heart failure in general.  相似文献   
75.
Seventeen male patients with ischaemic heart disease (IHD) and effort angina performed OBLA exercise stress tests (set to 2.0 mmol × 1–1). They had muscle biopsies from the vastus lateralis muscle the day before coronary by-pass grafting, and from the internal and external intercostal, diaphragm and gastrocnemius muscles during surgery. They had a low WOBLA (83 ± 6 W, mean ± 1 S.E.M), WOBLA corresponded to 79 ± 4% (% WOBLA) of WSL (symptom limited or maximal capacity = 111 ± 11 W). Peak blood lactate concentration averaged 2.9 mmol × 1–1. Muscle fibre composition disclosed a depressed percent slow twitch (ST or red) muscle fibres in the vastus lateralis and intercostal muscles (%ST). The diaphragm and gastrocnemius muscles had normal %ST. Intercostal muscles had elevated values for the fast twitch muscle fibre (FT) subgroup FTa indicative of endurance adaptation. The vastus lateralis, gastrocnemius and diaphragm muscles had normal muscle ubiquinone (UQ) contents, whereas the intercostals were depleted. Plasma contents of the antioxidants UQ and -tocopherol were low as compared to healthy man.The study was carried out by the Department of Thoracic Surgery, Karolinska Hospital, Stockholm, Sweden.  相似文献   
76.
Summary InPetunia hybrida frequent mutations of unstable alleles give rise to different types of periclinal chimeras. If genes expressed in the epidermis, such as the geneAn1 for flower colour, are concerned, mutations in the dermal layer of the shoot apex will result in changes in the phenotype but not in the offspring. Mutations in the subdermal layer will not lead to an altered phenotype, but to changes in the sporogenous tissues and, thus, to deviating segregations in progenies. Therefore, in crossing experiments with such an unstable mutant, it is always necessary to take the possibility into account that the plant may be a chimera, so as to prevent an incorrect interpretation of the recorded segregational ratios. Mutations of unstable alleles expressed in the mesophyll, such as geneYg3 for leaf colour, also give rise to chimeras. In such instances, however, a change in phenotype always involves a change in segregational ratios as well, since both the mesophyll and the sporogenous tissues are derived from the subdermal layer of the shoot apex.  相似文献   
77.
目的:探讨股骨近端解剖锁定钢板(PFLP)与股骨近端防旋髓内钉(PFNA)治疗不稳定型股骨转子间骨折的疗效。方法:选取我院2013年6月至2016年3月期间收治的160例不稳定型股骨转子间骨折患者为研究对象,采用乱数表法分为观察组、对照组,各80例。对照组采用PFLP治疗,观察组患者采用PFNA治疗。统计分析两组的手术及术后相关指标以及术后3个月、6个月、12个月的髋关节功能Harris评分,比较两组的术后并发症。结果:观察组患者的手术时间、切口长度短于对照组,术中出血量、术中输血量、术后引流量均少于对照组(P0.05);观察组患者术后患侧负重时间、住院时间均短于对照组(P0.05);观察组患者骨折愈合时间短于对照组,但无统计学差异(P0.05);术后3个月、6个月,观察组患者髋关节功能Harris评分均高于对照组(P0.05);术后12个月,观察组患者髋关节功能Harris评分高于对照组,但无统计学差异(P0.05);两组患者并发症发生率比较无统计学差异(P0.05)。结论:PFNA与PFLP均能够有效治疗不稳定型股骨转子间骨折,但PFNA治疗方式在近期疗效中的作用优于PFLP,且患者髋关节功能恢复更快。  相似文献   
78.
目的:探讨前列地尔联合硝酸异山梨酯对不稳定性心绞痛(UAP)患者血清细胞因子及血液流变学的影响。方法:选取2015年3月-2016年12月期间我院收治的UAP患者86例为研究对象,按照治疗方式的不同分为对照组和实验组,每组各43例。对照组给予硝酸异山梨酯治疗,实验组在硝酸异山梨酯的基础上加用前列地尔治疗,两组均连续治疗14d。对比两组治疗前后血清细胞因子水平变化、血液流变学参数变化、临床疗效以及不良反应发生情况。结果:治疗后两组白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、超敏C反应蛋白(hs-CRP)水平均明显降低,白细胞介素-10(IL-10)水平明显升高(P0.05),且实验组IL-6、TNF-α、hs-CRP水平较对照组降低,IL-10水平较对照组升高(P0.05)。治疗后两组舒张功能指数(O/C)、总电机械收缩期(QA2)、总外周阻力(TPR)均降低,每搏做功(SW)、搏功指数(SWI)、心脏指数(CI)、主动脉血管顺应性(AC)均升高(P0.05),治疗后实验组O/C、QA2、TPR较对照组降低,SW、SWI、CI、AC较对照组升高(P0.05)。实验组总有效率为95.35%,高于对照组的81.40%(P0.05)。两组治疗期间不良反应发生率比较差异无统计学意义(P0.05)。结论:前列地尔联合硝酸异山梨酯治疗UAP患者具有较好的疗效,可以控制患者的炎症反应,改善患者的血液流变学,无严重不良反应发生,值得临床推广。  相似文献   
79.
Unstable shoes (US) continually perturb gait which can train the lower limb musculature, but muscle co-contraction and potential joint stiffness strategies are not well understood. A shoe with a randomly perturbing midsole (IM) may enhance these adaptations. This study compares ankle and knee joint stiffness, and ankle muscle co-contraction during walking and running in US, IM and a control shoe in 18 healthy females. Ground reaction forces, three-dimensional kinematics and electromyography of the gastrocnemius medialis and tibialis anterior were recorded. Stiffness was calculated during loading and propulsion, derived from the sagittal joint angle-moment curves. Ankle co-contraction was analysed during pre-activation and stiffness phases. Ankle stiffness reduced and knee stiffness increased during loading in IM and US whilst walking (ankle, knee: p = 0.008, 0.005) and running (p < 0.001; p = 0.002). During propulsion, the opposite joint stiffness re-organisation was found in IM whilst walking (both joints p < 0.001). Ankle co-contraction increased in IM during pre-activation (walking: p = 0.001; running: p < 0.001), and loading whilst walking (p = 0.003), not relating to ankle stiffness. Results identified relative levels of joint stiffness change in unstable shoes, providing new evidence of how stability is maintained at the joint level.  相似文献   
80.
目的:探讨超敏CRP(hs-CRP)、半胱氨酸蛋白酶抑制剂C(CysC)联合检测对冠心病患者的意义。方法:收集120例冠心病(Coronary heart disease,CHD)患者(其中不稳定型心绞痛unstablangina,UA 62例,急性冠状动脉综合征AcuteCoronarySyndrome,ACS 48例,)选择60例性别、年龄、居住地等与冠心病组相匹配的正常者为对照组,测定hs-CRP、CysC水平。结果:hs-CRP、CysC水平在正常对照组、稳定型心绞痛组、急性冠状动脉综合征组中依次增高,恢复后hs-CRP比CysC下降的速度更快,CysC在恢复期更能提醒病人的预后情况,冠心病组与正常对照相比有统计学意义(P<0.01),治疗后与治疗前hs-CRP、CysC的浓度相比(P<0.01)差异有显著性。治疗后hs-CRP敏感度分别为20.96%、24.19%;CysC敏感度分别为47.91%、52.08%。结论:hs-CRP、CysC与CHD发生、发展密切相关,联合检测有利于冠心病的早期诊断。对于临床的分型和病情的发展及预后的观察有极其重要的意义。  相似文献   
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