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41.
The reliability and durability of lithium‐ion capacitors (LICs) are severely hindered by the kinetic imbalance between capacitive and Faradaic electrodes. Efficient charge storage in LICs is still a huge challenge, particularly for thick electrodes with high mass loading, fast charge delivery, and harsh working conditions. Here, a unique thermally durable, stable LIC with high energy density from all‐inorganic hydroxyapatite nanowire (HAP NW)‐enabled electrodes and separators is reported. Namely, the LIC device is designed and constructed with the electron/ion dual highly conductive and fire‐resistant composite Li4Ti5O12‐based anode and activated carbon‐based cathode, together with a thermal‐tolerant HAP NW separator. Despite the thick‐electrode configuration, the as‐fabricated all HAP NW‐enabled LIC exhibits much enhanced electrochemical kinetics and performance, especially at high current rates and temperatures. Long cycling lifetime and state‐of‐the‐art areal energy density (1.58 mWh cm?2) at a high mass loading of 30 mg cm?2 are achieved. Benefiting from the excellent fire resistance of HAP NWs, such an unusual LIC exhibits high thermal durability and can work over a wide range of temperatures from room temperature to 150 °C. Taking full advantage of synergistic configuration design, this work sets the stage for designing advanced LICs beyond the research of active materials. 相似文献
42.
Alaa A.M. Al-Nahari Saad B. Almasaudi El Sayed M. Abd El-Ghany Elie Barbour Soad K. Al Jaouni Steve Harakeh 《Saudi Journal of Biological Sciences》2015,22(5):521-525
Five types of imported and local honey were screened for both their bacteriocidal/bacteriostatic activities against both Imipenem resistant and sensitive Pseudomonas aeruginosa in both Brain Heart infusion broth and Mueller–Hinton agar. The results indicated that the effect was concentration and type of honey dependant. All types of honey tested exerted a full inhibition of bacterial growth at the highest concentration tested of 50% at 24 h of contact. The inhibitory effect of honey on bacterial growth was clear with concentrations of 20% and 10% and this effect was most evident in the case of Manuka honey as compared to Nigella sativa honey and Seder honey. Manuka honey UMF +20 showed a bacteriocidal activity on both Imipenem resistant and sensitive P. aeruginosa, while Seder honey and N. sativa honey exerted only a bacteriostatic effect. Manuka honey UMF +10 showed most effect on antimicrobial resistance. Manuka honey UMF +10 had an effect on modulation of Imipenem resistant P. aeruginosa. Conclusion: The results indicated that various types of honey affected the test organisms differently. Modulation of antimicrobial resistance was seen in the case Manuka honey UMF +10. 相似文献
43.
玉蜀黍赤霉(Gibberella zeae)对多菌灵的室内抗药突变体的诱导及其抗药性遗传分析 总被引:5,自引:0,他引:5
通过紫外线照射和药剂驯化的方法均获得了玉蜀黍赤霉野生敏感菌株对多菌灵(carbendazim,MBC)的室内抗药突变体。这些抗药突变体一部分表现低抗(low resistance.LR),即能在临界致死剂量1.4μg/mL多菌灵浓度下生长,但不能在10μg/mL浓度以上生长,且对二氯苯胺甲酸甲酯(N-3,5-dichlorophenyl carbamate,MDPC)不表现负交互抗药性;另一部分表现高抗(high resistance.HR).即能在100μg/mL多菌灵浓度下生长,并与田间高抗菌株一样,对MDPC表现负交互抗药性;没有获得类似田间的中抗(moderate resistance,MR)菌株,即能在10μg/mL多菌灵浓度下快速生长,在100μg/mL浓度以上被完全抑制的突变体。通过药剂驯化的方法还获得了田间中抗(MR)菌株的高抗(HR)突变体,但这些突变体与MR一样对MDPC仍然不表现负交互抗药性。抗药性遗传研究表明。在所研究的抗药突变体中,抗药性在自交和无性繁殖后代中能稳定遗传;室内抗药突变体和田间抗药菌株对多菌灵的抗药性由同一个主效基因控制,但它们发生突变的位点不同或者同一碱基位点发生了不同的突变;对MDPC的敏感性也是由单个基因控制的,该基因与控制多菌灵抗性的基因是等位基因,当该基因发生对MDPC的敏感性增加的突变时会使病菌对多菌灵产生高水平抗性。 相似文献
44.
摘要 目的:探讨与分析呼吸道感染患者多重耐药菌肺炎克雷伯菌的耐药及危险因素。方法:选择2015年1月到2020年2月本院诊治的呼吸道感染患者65例作为研究对象,收集患者的临床样本进行细菌分离与耐药分析,调查患者的临床资料并进行危险因素分析。结果:在呼吸道感染患者65例中,分离出多重耐药菌肺炎克雷伯菌32株,占比49.2 %,其中下呼吸道、上呼吸道、灌洗液、血液标本分别占50.0 %、9.4 %、25.0 %、6.3 %。32株多重耐药菌肺炎克雷伯菌对头孢曲松、头孢呋辛、氨苄西林、头孢吡肟、头孢噻肟的耐药率分别为71.9 %、87.5 %、96.9 %、84.4 %、81.3 %,对阿米卡星、头孢替坦、左氧氟沙星、亚胺培南、环丙沙星的敏感率分别为59.4 %、68.8 %、81.3 %、75.0 %、81.3 %。非条件 Logistic回归分析显示血型A型、碳青霉烯类抗菌药物使用、引流、机械通气、糖尿病等为导致多重耐药菌肺炎克雷伯菌感染的独立危险因素(P<0.05)。结论:多重耐药菌肺炎克雷伯菌感染在呼吸道感染患者中比较常见,对头孢呋辛、氨苄西林的耐药率比较高,对左氧氟沙星、环丙沙星的敏感率比较高,血型A型、碳青霉烯类抗菌药物使用、引流、机械通气、糖尿病等为导致多重耐药菌肺炎克雷伯菌感染的独立危险因素。 相似文献
45.
46.
Circumvention of multidrug resistance and reduction of cardiotoxicity of doxorubicin in vivo by coupling it with low density lipoprotein 总被引:1,自引:0,他引:1
Doxorubicin (Dox) was coupled into human low density lipoprotein (LDL) to form a complex LDL-Dox. In in vitro studies, the accumulation of LDL-Dox in human resistant hepatoma (R-HepG2) cells was found to be higher than that of free Dox in the cells, resulting in an increase of the cytotoxic effect on the cells. Moreover, in in vivo studies, under the same dosage of drugs (1 mg/kg), the anti-proliferative effect on the tumor cells of LDL-Dox in nude mice bearing R-HepG2 cells was higher than that of free Dox as evidenced by the larger reduction in tumor volumes and tumor weights in LDL-Dox treated group. Histological studies showed that LDL-Dox treatment did not cause any heart damage when compared with the control group. In contrast, Dox treatment caused disruption and vacuolization of myocardial filament. Plasma lactate dehydrogenase activity and plasma creatine kinase activity in nude mice bearing R-HepG2 cells were found to be elevated in the Dox-treated group but remained unchanged in LDL-Dox-treated group. The present studies indicate that when Dox is coupled with LDL, the multidrug resistance can be circumvented and the cardiotoxicity can be reduced. 相似文献
47.
AIMS: In vitro studies have suggested that fructo-oligosaccharides (FOS) and resistant starch (two fermentable non-digestible carbohydrates) display different fermentation kinetics. This study investigated whether these substrates affect the metabolic activity and bacterial composition of the intestinal microflora differently depending on the caecocolonic segment involved. METHODS AND RESULTS: Eighteen rats were fed a low-fibre diet (Basal) or the same diet containing raw potato starch (RPS) (9%) or short-chain FOS (9%) for 14 days. Changes in wet-content weights, bacterial populations and metabolites were investigated in the caecum, proximal and distal colon and faeces. Both substrates exerted a prebiotic effect compared with the Basal diet. However, FOS increased lactic acid-producing bacteria (LAPB) throughout the caecocolon and in faeces, whereas the effect of RPS was limited to the caecum and proximal colon. As compared with RPS, FOS doubled the pool of caecal fermentation products, while the situation was just the opposite distally. This difference was mainly because of the anatomical distribution of lactate, which accumulated in the caecum with FOS and in the distal colon with RPS. Faeces reflected these impacts only partly, showing the prebiotic effect of FOS and the metabolite increase induced by RPS. CONCLUSIONS: This study demonstrates that FOS and RPS exert complementary caecocolonic effects. SIGNIFICANCE AND IMPACT OF THE STUDY: The RPS and FOS combined ingestion could be beneficial by providing health-promoting effects throughout the caecocolon. 相似文献
48.
KCN和NaN3预处理对烟草愈伤组织抗氰呼吸的影响 总被引:3,自引:0,他引:3
用0.5 m m ol/L KCN 或0.01 m m ol/L NaN3 预处理继代培养25 d 的“甘肃黄花烟草”(Nicotiana rustica L. cv. Gansu yellow flow er)愈伤组织对其呼吸作用有明显的影响。KCN 和NaN3 预处理12 h 可分别使愈伤组织的总呼吸速率下降12% 和17% ,细胞色素途径的实际运行量分别下降22% 和28% ;抗氰交替途径在最大容量(Valt)基本不变的情况下,实际运行量(ρ·Valt)不但未随总呼吸速率和细胞色素途径运行量的下降而降低,反而还略有上升。结果导致细胞色素途径对总呼吸的贡献下降而抗氰交替途径对总呼吸的贡献上升。KCN 预处理24 h,细胞色素途径的实际运行量虽略有回升,但仍低于对照;NaN3 预处理24 h 则使细胞色素途径运行继续下降而交替途径运行持续上升。上述结果表明,在继代培养的烟草愈伤组织中,当细胞色素主路途径被部分抑制后交替途径的电子流量明显加强,从而起着一种补偿作用 相似文献
49.
50.
Yoichi Honda Toshikazu Irie Mina Atsuji Takashi Watanabe Masaaki Kuwahara 《Mycoscience》1996,37(4):459-461
To develop a dominant genetic marker inPleurotus ostreatus, mutant strains resistant to a carboxin-derived fungicide, flutolanil, were isolated. These mutants included strains which
showed resistance to 50-fold higher concentration of fluotolanil than the wild-type strain, even after successive cultivations
in the absence of the drug. Dominance of the phenotype was confirmed by back-crossing between the resistant and wild-type
monokaryons. The flutolanilresistance was also shown to be stably inherited by the basidiospore-derived progenies of the mutant
strains. 相似文献