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目的 探讨酚妥拉明、多巴胺联合黄芪注射液治疗慢性肺心病的临床疗效.方法 对64例肺心病心衰的住院患者在常规综合治疗的基础上加用多巴胺、酚妥拉明、黄芪注射液治疗,并观察临床效果.结果 显效46例,好转13例,无效5例,总有效率92.19%.结论 在常规治疗的基础上加用酚妥拉明、多巴胺联合黄芪注射液治疗慢性肺心病心衰的疗效显著,且经济实用,值得推广. 相似文献
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【背景】联苯菊酯是人工合成的类似天然除虫菊素的一种仿生杀虫剂,近年来被广泛应用于农业病虫害的防治。联苯菊酯化学性质较稳定,在环境中的残留期长,是我国出口果蔬、茶叶中残留较严重的农药之一。微生物降解具有降解速度快、无二次污染等优点,被认为是有效去除农药残留的绿色生产技术。【方法】通过富集驯化,从农药厂排污口的污泥中筛选分离能够降解联苯菊酯的菌株,经形态学观察、生理生化特性测定及16SrRNA序列分析对其进行鉴定,通过单因素试验对菌株的降解特性进行研究。【结果】分离到1株联苯菊酯的降解菌株BF-3。菌株BF-3为革兰氏阳性菌,被鉴定为蜡状芽孢杆菌;该菌株在联苯菊酯质量浓度为100mg·L^-1的无机盐液体培养基(MSM)中呈现s型生长,7d后对联苯菊酯的降解率达到87.9%。单因素试验表明,菌株最适降解条件为pH7.0、30oC,初始菌株D600am=1.0。【结论与意义】蜡状芽孢杆菌BF.3能够有效降解联苯菊酯,在环境中联苯菊酯残留的生物修复方面具有应用潜力。 相似文献
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Moises Joao Zotti Anderson Dionel Grutzmacher Isac Heres Lopes Guy Smagghe 《Entomologia Sinica》2013,(6):743-752
The comprehensive knowledge that the delayed systemic and reproduction side effects can be even more deleterious than acute toxicity, has caused a shift in focus toward sublethal effects assessment on physiology and behavior of beneficial insects. In this study, we assessed the risks posed by some insecticides with different mode of action through lethal and delayed systemic sublethal effects on the pupation, adult emergence, and repro- duction of the chrysopid Chrysoperla externa (Hagen, 1861; Neuroptera: Chrysopidae), an important predator in pest biological control. The maximum field recommended dose (MFRD) and twice (2xMFRD) for chlorantraniliprole, tebufenozide, and pyriproxyfen were harmless to C. externa. In contrast, all the tested chitin synthesis inhibitors (CSIs) were highly detrimental to the predator, despite of their lack of acute lethal toxicity. There- fore, the safety assumed by using IGRs toward beneficial insects is not valid for chrysopids. Dose-response data showed that although all CSIs have a similar mechanism of action, the relative extent of toxicity may differ (novaluron 〉 lufenuron 〉 teflubenzuron). For CSIs, the delayed systemic effects became obvious at adult emergence, where the predicted no observable effect dose (NOED) was 1/2 048 of the MFRD for novaluron (0.085 ng/insect), and 1/256 of the MFRD for both lufenuron (0.25 ng/insect) and teflubenzuron (0.6 ng/insect). Finally, this work emphasized the significance of performing toxicity risk assessments with an adequate posttreatment period to avoid underestimating the toxicities of insecticides, as the acute lethal toxicity assays may not provide accurate information regarding the long-range effects of hazardous compounds. 相似文献
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Articular cartilage lubricates the contact surfaces in human joints and provides a shock-absorbing effect which protects the joint under dynamic loading. However, this shock-absorbing effect is gradually reduced as the result of normal wear, tear and aging-related cartilage loss. Thus, with the increasing average human life expectancy, the issue of joint health has attracted significant interest in recent decades. In developing new materials for the repair or regeneration of damaged articular cartilage, it is essential that the difference in the mechanical properties of healthy and damaged cartilages is well-understood. In the present study, the hardness and Young's modulus of damaged and healthy porcine articular cartilage samples are evaluated via a quasi-static nanoindentation technique. A dynamic mechanical analysis method is then applied to determine the viscoelastic properties of the two samples. The results presented in this study provide a useful insight into the mechanical properties of articular cartilage at the mesoscale, and therefore fill an important gap in the literature. 相似文献
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Yali She Yi Li Yongqi Liu Guli Asai Shaobo Sun Jianxin He Zheng Pan Yan Cui 《Acta biochimica et biophysica Sinica》2013,(12):1011-1020
In this study, we assessed the toxic effects of formaldehyde (FA) on mouse bone marrow mesenchymai stem cells (BM- MSCs). Cytotoxicity was measured by using MTT assay. DNA strand breakage was detected by standard alkaline comet assay and comet assay modified with proteinase K (PK). DNA-protein crosslinks (DPCs) were detected by KCI-SDS precipitation assay. We found that FA at a con- centration from 75 to 200 μM inhibited cell survival and induced DPCs over 125 μM. The PK-modified comet assay showed that FA-induced DNA strand breakage was increased in a dose-dependent manner from 75 to 200 μM. On the other hand, standard alkaline comet assay showed that DNA strand breakage was decreased with FA concen- tration over 125 μM. We confirmed by using Pearson cor- relation that there was a negative linear correlation between DPCs and survival rate (r = -0.987, P 〈 0.01) and positive linear relationships between DPCs and (i) sister chromatid exchange and (ii) micronucleus (r = 0.995, P〈 0.01; r = 0.968, P〈 0.01). DNA damage RTz profiler polymerase chain reaction array was used to investigate the changes in the expression of damage response genes. Xpa and Xpc of the nucleotide excision repair pathway and Brca2, Rad51, and Xrcc2 of the homologous recombination pathway were all up-regulated in both 75 and 125 μM FA. However, the same genes were down-regulated with 175 μM FA. The expressions of Chekl and Husl, which are involved in cell cycle regulation, were altered in the same manner with 75, 125, and 175 μM FA. These results indicated that Xpa, Xpc, Brca2, Rad51, Xrcc2, Chekl, and Husl were essential for the BM-MSCs to counteract the effects of FA. 相似文献
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目的:2011年,我国糖尿病患者人数高达9240万。糖尿病视网膜病变(diabeticretinopathy,DR)作为糖尿病患者的常见并发症,在糖尿病人群中的患病率为37%,是导致成人获得性盲的最主要原因之一。严重增生性糖尿病视网膜病变以牵拉性视网膜脱离、玻璃体出血为特征,具有致盲率大,手术难度高等特点。针对与此,本文主要探讨术前注射贝伐单抗对23G玻璃体切割手术治疗严重增生性糖尿病视网膜病变患者效果的影响。方法:回顾性病例对照研究。共收集严重增生性糖尿病视网膜病变患者70例,药物辅助手术组(A组)21例,术前3—7天行玻璃体腔注射贝伐单抗(1.25mg/O.05mL);单纯手术组(B组)49例,行23G玻璃体切割术。分析两组术前及术后视力、手术时间、医源性裂孔、电凝、术后出血的不同。结果:在术后3月,两组视力提高有统计学意义(P〈O.05)。A组平均手术时间为74分钟,而B组平均手术时间为85分钟(P〉0.05)。医源性裂孔在A组中有1例,而B组中有16例(P〈0.05),在A组中有3例使用电凝,B组中有25例使用电凝(P〈0.05)。A组有1例出现术中及术后出血,B组为20例(P〈O.05)。结论:在这个回顾性研究中,我们发现对于严重增生性糖尿病视网膜病变的病人,术前玻璃体腔注射1.25mg/O.05ml贝伐单抗可以显著减少医源性裂孔的发生,减少术中电凝使用及术中术后出血的发生。 相似文献