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101.
目的探讨知柏地黄汤治疗解脲脲原体感染所致男性不育症的可能机制。方法采用经大鼠膀胱注射解脲脲原体标准株菌液2 ml/只建立解脲脲原体感染大鼠模型,将造模成功的64只大鼠随机分为中药组、西药组、中西组、模型组,每组16只,另设假手术组15只。造模成功后第2天假手术组、模型组用0.9%氯化钠注射液2 ml/d灌胃,中药组给予知柏地黄汤1.88 g生药/d,西药组给予强力霉素4 mg/d,中西组给予等量的知柏地黄汤与强力霉素,各组均连续灌胃21天。检测大鼠精子线粒体膜通道孔(m PTP)开放程度及精子线粒体二磷酸腺苷(ADP)、三磷酸腺苷(ATP)、一磷酸腺苷(AMP)含量,计算能荷(EC)值。结果与假手术组比较,模型组大鼠精子m PTP开放吸光度值下降,精子ATP、ADP及EC降低,AMP值上升(P<0.01)。与模型组比较,各治疗组大鼠精子m PTP开放吸光度值均有上升,西药组、中西组大鼠精子ATP、ADP及EC值上升,AMP值下降(P<0.05或P<0.01)。与中药组比较,中西组大鼠精子m PTP开放吸光度值上升(P<0.05);中西组大鼠精子ATP高于中药组和西药组,中西组ADP及EC值高于中药组(P<0.05或P<0.01)。结论知柏地黄汤能够降低解脲脲原体感染大鼠精子m PTP开放程度,维护线粒体能量代谢,进而提高精子质量,这可能是其治疗解脲脲原体感染所致不育症的机制之一。 相似文献
102.
Energy harvesting devices made of piezoelectric material are highly anticipated energy sources for power wireless sensors. Tremendous efforts have been made to improve the performance of piezoelectric energy harvesters (PEHs). Noticeably, topology optimization has shown an attractive potential to design PEHs with enhanced energy conversion efficiency. In this work, an alternative yet more practical design objective was considered, where the open-circuit voltage of PEHs is enhanced by topologically optimizing the through-thickness piezoelectric material distribution of plate-type PEHs subjected to harmonic excitations. Compared to the conventional efficiency-enhanced designs, the open-circuit voltage of PEHs can be evidently enhanced by the proposed method while with negligible sacrifice on the energy conversion efficiency. Numerical investigations show that the voltage cancellation effect due to inconsistent voltage phases can be effectively ameliorated by optimally distributed piezoelectric materials. 相似文献
103.
Energy sustainability represents an important research topic for aiding decreasing energy dependence and slowing down climate changes. In this context, solutions using thermal energy storage through rock start to emerge, due to its natural benefits, when compared to more polluting alternatives. To understand whether a rock material can be considered a good thermal energy storage material for such solutions, it is necessary to evaluate the physical, chemical and thermal properties of such materials. Therefore, it becomes essential to understand how heat propagates in the rock and how voids influence the thermal properties. To achieve these goals, hematite ore from Moncorvo, Northeastern Portugal was used, in particular, to study the effect of grain size on thermal properties for three different sized lots. Chemical and physical changes between heated and unheated lots were detected using X-ray diffraction and particle size, as well as X-ray fluorescence analysis. Regarding thermal properties, a hot wire method approach was used with seven thermocouples. Additionally, a thermal inversion model to simulate the heat exchanges was also proposed, allowing changing the properties of the constituents, to fit the theoretical and experimental temperature curve. Furthermore, the model reveals how heat propagates inside the reservoir filled with hematite ore. 相似文献
104.
目的 探讨双能量CT(DECT)半定量评分系统在痛风患者尿酸盐结晶评估中的可行性及应用价值。方法 回顾性分析2013年8月至2017年8月江苏大学附属澳洋医院39例痛风患者的足部DECT扫描结果,并对其尿酸盐结晶进行半定量评分。应用DECT定量软件测量尿酸盐结晶体积;采用组内相关系数(ICC)评估半定量评分重复性;使用Spearman相关性分析半定量评分与尿酸盐体积的相关性;同时比较半定量评分方法与定量软件测量尿酸盐体积方法所用时间。结果 39例患者共完成了73只足部扫描,其中69只足部检测到尿酸盐结晶。DECT尿酸盐结晶评分在肌腱中最高,其次为第一跖趾关节、踝/中足关节,脚趾的其他关节评分最低。2名影像医师对尿酸盐结晶的半定量分析结果一致性高,ICC为0.944。69只足部的尿酸盐结晶体积平均值为(2.69±8.84)cm3。DECT尿酸盐评分与其体积密切相关(r=0.479,P<0.001)。两名评分者使用DECT评分系统分析尿酸盐结晶所需时间分别为(68.18±15.16)秒、(74.67±16.15)秒,定量软件分析所需时间为(166.10±13.23)秒,三者之间差异有统计学意义(F=527.029,P<0.001)。结论 DECT尿酸盐结晶半定量评分系统是可行的,相比定量分析软件更省时、方便,值得推广应用。 相似文献
105.
目的 探索组胺对脂肪细胞能量代谢的影响及其作用机制。方法 培养3T3L1细胞,诱导分化为白色脂肪细胞,运用RT-PCR以及Western-blot技术检测组胺和苯海拉明对白色脂肪细胞中UCP2 mRNA水平和蛋白质表达水平的影响。结果 白色脂肪细胞在不同剂量组组胺的刺激下,UCP2的表达值在不同剂量组之间存在显著差异(P〈0.05),UCP2的表达水平随着组胺剂量的增加而增加,在组胺剂量为30μmol·L^-1时达到最高值;在相同剂量组胺下,观察不同时间对细胞内UCP2表达的影响,结果发现,不同时间组之间也存在显著性差异(P〈0.05),当时间为6h时,UCP2表达量达到最高;苯海拉明剂量依赖性地抑制脂肪细胞UCP2 mRNA水平和蛋白质的表达。结论 组胺可以刺激分化成熟的3T3L1细胞中UCP2的表达,其机制与激活H1受体有关。 相似文献
106.
Arul Prakash Francis Thiyagarajan Devasena Selvam Ganapathy Venkata Rajsekhar Palla Prakhya Balakrishna Murthy Sundara Ramaprabhu 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(6):1809-1822
Human beings and ecosystems are being possibly exposed to CNTs, as there is a rise in global production rate of carbon nanotubes (CNTs). This may affect the health of humans and increases the environmental risk. We have already reported the pulmonary toxicity due to the inhalation of MWCNTs. We claim that a compound with anti-inflammatory and antioxidant activity may ameliorate the CNT-induced toxic effect. With this view, we have investigated the ameliorative effect of intravenously-administered nano bis-demethoxy curcumin analog (NBDMCA) against MWCNTs-induced inhalation toxicity by examining the lung histopathology for inflammatory cell dynamics, pulmonary remodeling and estimating the inflammatory biomarkers in the broncho-alveolar lavage fluid. We observed that NBDMCA could ameliorate the injury as evidenced by the decline in the levels of markers of inflammation, cell damage, and the histopathological changes induced by MWCNTs. We conclude that NBDMCA may be used to reduce the risk of MWCNTs-induced inhalation toxicity. 相似文献
107.
目的 观察高能冲击波对肾脏钙离子腺苷三磷酸酶(Ca2+-ATPase)活性的影响及川芎嗪的保护作用,探讨高能冲击波肾损伤机制.方法 30只健康家兔制成单肾动物模型,按完全随机设计法分为对照组10只、高能冲击波组10只和川芎嗪组10只,对照组、高能冲击波组分别静脉注射等量生理盐水,高能冲击波冲击肾脏前3天,川芎嗪组静脉注射川芎嗪;冲击肾脏24h后,光学法检测肾细胞膜和线粒体膜Ca2+-ATPase活性;采用原位缺口末端标记法和流式细胞术检测凋亡细胞;采用生化分析测定内生肌酐清除率.结果 与对照组比较,高能冲击波组肾细胞膜和线粒体膜Ca2+-ATPase活性均降低(P<0.05,P<0.01)、细胞凋亡率增加(P<0.01)、内生肌酐清除率降低(P<0.01);川芎嗪组肾细胞膜Ca2+-ATPase活性和内生肌酐清除率变化不明显(P>0.05),线粒体膜Ca2+-ATPase活性降低(P<0.05)、细胞凋亡率增加(P<0.05),但幅度明显小于高能冲击波组.结论 高能冲击波冲击肾脏后肾脏Ca2+-ATPase活性降低是发生肾细胞凋亡导致肾功能损伤的重要机制,川芎嗪有改善肾功能的作用,与其阻制肾脏Ca2+-ATPase活性降低、抗细胞凋亡有关. 相似文献
108.
Nirmal Ponnambalam Sarathkumar Thangavel Gunasekaran Murali Nikolai Ivanovich Vatin 《Materials》2022,15(15)
Concrete is the most widely used and most affordable construction material. The structural damage that concrete cracks and fractures may cause can be severe. These concerns have lately been alleviated by new developments in fibre concretes. Recent advancements in fibrous concrete and its evolution have been rapidly drawing researchers’ attentions worldwide, which motivates the development of a new type of composite with superior impact resistance. Preplaced aggregate fibrous concrete (PAFC) is a revolutionary composite comprising a higher dosage of fibres. It has outstanding impact resistance that surpasses those of traditional fibrous concrete. The impact behaviour of PAFC in addition to glass fibre mesh (GFM) has not been investigated thoroughly. To fill this research gap, this study investigates the impact performance of three-layered PAFC comprising steel fibres and GFM insertion. Eight different mixtures were prepared and can be divided into two groups. In the first group, specimens were made with 4% fibres and two single, double and triple layers of GFM insertion between the three-layered concrete. The second group of specimens was reinforced with 5, 2 and 5% steel fibres at the top, middle and bottom layers, respectively. However, the GFM insertion scheme for the second group was the same as the first. Rectangular specimens of size 500 × 100 × 100 mm were cast and tested against drop weight impact. The parameters studied were cracking impact numbers, failure impact number, ductility index and failure patterns. In addition, an analytical model was used to evaluate the impact failure energies. Results indicate that the combined action of steel fibre and GFM exhibited an excellent impact resistance. Increasing the number of GFM insertions between the specimen layer led to increased impact strength. The dose of the fibres utilized in the outer layer of the PAFC was increased, resulting in the material having a higher impact resistance. The cracking impact numbers improved from 28 to 40%, and failure impact numbers ranged from 58.8 to 92.2% when the GFM insertion numbers increased from one to three. 相似文献
109.
Two mesomechanics models were analyzed in an attempt to reveal the relationship between stored energy and back stress. It has been indicated that the portion of elastic stored energy due to residual microstresses (ESR) is closely related to intergranular back stress (Xinter), and the stored energy of dislocations inside grains (ESD) can be estimated with the plastic work of intragranular back stress (Xintra). Then, the evolution of back stress during cyclic loading was studied, and the plastic work of back stress (WpB) was calculated with the low cycle fatigue experimental data of Ti-6Al-4V. The result shows that WpB is partially released at every reverse loading, sufficient to reproduce the evolution of stored energy correctly under cyclic loading. The study also reveals that partially released energy is related to the decrease of Xinter at the initial state of reversal loading resulting from the reduction of the plastic strain incompatibility between grains. 相似文献
110.
Bouchra Asbani Yaovi Gagou Said Ben Moumen Jean-Luc Dellis Abdelilah Lahmar MBarek Amjoud Daoud Mezzane Mimoun El Marssi Brigita Rozic Zdravko Kutnjak 《Materials》2022,15(15)
Ferroelectric property that induces electrocaloric effect was investigated in Ba(GexTi1−x)O3 ceramics, known as BTGx. X-ray diffraction analysis shows pure perovskite phases in tetragonal symmetry compatible with the P4mm (No. 99) space group. Dielectric permittivity exhibits first-order ferroelectric-paraelectric phase transition, confirmed by specific heat measurements, similar to that observed in BaTiO3 (BTO) crystal. Curie temperature varies weakly as a function of Ge-content. Using the direct and indirect method, we confirmed that the adiabatic temperature change ΔT reached its higher value of 0.9 K under 8 kV/cm for the composition BTG6, corresponding to an electrocaloric responsivity ΔT/ΔE of 1.13 × 10−6 K.m/V. Such electrocaloric responsivity significantly exceeds those obtained so far in other barium titanate-based lead-free electrocaloric ceramic materials. Energy storage investigations show promising results: stored energy density of ~17 mJ/cm3 and an energy efficiency of ~88% in the composition BTG5. These results classify the studied materials as candidates for cooling devices and energy storage applications. 相似文献