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1.
介绍了国内发明专利中拖拉机及车辆维护用先进材料的新进展,其中包括制动材料、密封材料、润滑材料、快速堵漏剂、防冻液、防垢除垢材料、清洗剂、轮胎自补剂、涂料及修理工护肤产品等。  相似文献   
2.
针对高等农林院校学生高级语言程序设计水平不同,实施分级分层次教学可以较好地实现以人为本,以学生为主体的现代教学理念,提高高级语言程序设计课程教学质量,更好地满足农林专业人才的培养和社会需求。农林院校高级语言程序设计课程分级教学需要解决师资素质、教学成本、教学管理和学生心理等主要问题,需要强化以人为本的教学理念,提升师资队伍教学水平;科学选择或编写教材,认真规划设计教学内容;增加教学软硬件等设施投入,提高现代化教学管理水平;增强教师人文关怀意识,强化学生身心健康水平。  相似文献   
3.
Despite the recognised importance of oxidative stress in the health and immune function of dairy cows, protein oxidation markers have been poorly studied in this species. The current study aimed to characterise markers of protein oxidation generated by activated bovine neutrophils and investigate the biological effects of advanced oxidation protein products (AOPP) on bovine neutrophils. Markers of protein oxidation (AOPP, dityrosines and carbonyls) were measured in culture medium containing bovine serum albumin (BSA) exposed to neutrophils. The effect of AOPP-BSA on generation of reactive oxygen species (ROS) was assessed by chemiluminescence. Activation of caspases-3, -8 and -9 and the presence of DNA laddering were used as apoptosis markers.Greater amounts of AOPP were generated by phorbol myristate acetate (PMA)-activated than non-activated neutrophils (1.46 ± 0.13 vs. 0.75 ± 0.13 nmol/mg protein, respectively; P < 0.05). Activated neutrophils and hypochlorous acid generated slightly different patterns of oxidized protein markers. Exposure to AOPP-BSA did not stimulate ROS production. Activated neutrophils generated a lesser amount of ROS when incubated with AOPP-BSA (P < 0.001). Activation with PMA induced a loss of viable neutrophils after 3 h, which was greater with AOPP-BSA incubation (P < 0.05). Detectable amounts of active caspases-3, -8 and -9 were found in nearly all samples but differences in caspase activation or DNA laddering were not observed comparing treatment groups. Apoptosis was unlikely to be responsible for the greater loss of PMA-activated neutrophils cultured in AOPP-BSA and it is possible that primary necrosis occurred. The results suggest that accumulation of oxidized proteins at an inflammatory site might result in a progressive reduction of neutrophil viability.  相似文献   
4.
微囊藻毒素是富营养化淡水水体中最常见的藻类毒素,它是一类具有多种异构体的环状多肽物质。较详细地介绍了水体中微囊藻毒素的结构、特性及其危害,并综述了有关其检测方法及降解技术的国内外最新研究进展;最后,对微囊藻毒素降解技术的发展方向进行了探讨和展望。  相似文献   
5.
介绍了腈纶厂废水的主要来源和危害,并综述了几种高级氧化法在处理腈纶废水、丙烯腈废水中的研究进展,同时分析了高级氧化法处理腈纶厂废水的作用机理、优势和存在的问题,并对其应用前景提出了展望。  相似文献   
6.
AIM:To investigate the effect of advanced glycation end products (AGEs) on the activity of rynodine receptor (RyR) and calcium regulation in cardiomyocytes, in order to clarify the underlying mechanisms of cardiac dysfunction in diabetic cardiomyopathy. METHODS:The frequency and morphology of spontaneous calcium sparks were observed in cultured neonatal rat ventricular myocytes by the imaging technique of laser scanning confocal microscope. RESULTS:Compared with control group, AGEs increased the frequency of calcium sparks, where 10 mg/L of AGEs increased by 48% (P<0.01), 50 mg/L of AGEs increased by 200% (P<0.01) and 150 mg/L of AGEs increased by 110% (P<0.01). AGEs alter the morphology of spontaneous calcium sparks. AGEs decreased the amplitude and width of calcium sparks, and calcium spark duration. AGEs increased the level of cardiomyocyte resting Ca2+. CONCLUSION: AGEs increases the frequency of spontaneous calcium sparks, thereby enhancing calcium spark-mediated leaking of sarcoplasmic reticulum Ca2+, which may be the cause of diabetic cardiomyopathy systolic dysfunction.  相似文献   
7.
Ginger is considered by many people to be the outstanding member among 1400 other species in the family Zingiberaceae. Not only it is a valuable spice used by cooks throughout the world to impart unique flavour to their dishes but it also has a long track record in some Chinese and Indian cultures for treating common human ailments such as colds and headaches. Ginger has recently attracted considerable attention for its anti-inflammatory, antibacterial and antifungal properties. However, ginger as a crop is also susceptible to at least 24 different plant pathogens, including viruses, bacteria, fungi and nematodes. Of these, Pythium spp. (within the kingdom Stramenopila, phyllum Oomycota) are of most concern because various species can cause rotting and yield loss on ginger at any of the growth stages including during postharvest storage. Pythium gracile was the first species in the genus to be reported as a ginger pathogen, causing Pythium soft rot disease in India in 1907. Thereafter, numerous other Pythium spp. have been recorded from ginger growing regions throughout the world. Today, 15 Pythium species have been implicated as pathogens of the soft rot disease. Because accurate identification of a pathogen is the cornerstone of effective disease management programs, this review will focus on how to detect, identify and control Pythium spp. in general, with special emphasis on Pythium spp. associated with soft rot on ginger.  相似文献   
8.
利用简并PCR技术和RACE技术克隆得到了一条洋葱的苯丙氨酸解氨酶(PAL)基因全长cDNA序列。该cDNA序列全长2349 bp,编码长685个氨基酸残基的多肽序列,命名为AcPAL2。Blast分析表明该序列与虎眼万年青Galtonia saundersiae、野蕉Musa balbisiana的相似性均较高。Real-time PCR表达及花青素含量分析表明,红皮洋葱该基因表达量最大,而黄皮和白皮洋葱表达量极低;在红皮洋葱中该基因在膨大初期大量表达,并迅速降低至一定程度后趋于相对平稳表达,且与花青素的积累过程相一致。  相似文献   
9.
Although the Advanced Backcross strategy has proven very useful for QTL detection in tomato, it has been used mainly in identifying QTL for agronomic traits such as yield, color, etc. Tomato flavor is an important quality characteristic, yet it has been difficult to assess flavor or traits that affect it. In this study the AB-QTL strategy was applied to four advanced backcross populations to identify QTL for biochemical properties that may contribute to the flavor of processed tomatoes, such as sugars and organic acids. A total of 222 QTL were identified for 15 traits, including flavor as assessed by a taste panel. Correlations of certain biochemicals with flavor and possible methods of assessing and improving flavor are discussed. In particular, QTL with very significant effects associated with the ratio of sugars/glutamic acid, a trait highly correlated with improved flavor, have been identified as good targets for future work in improving the flavor of tomatoes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
10.
提出的加密方案是AES算法在数字图书馆中的应用和改进。改进的新算法采用Logistic映射初值作为种子密钥生成混沌序列,对该序列进行域值量化得到二进制密钥流,对其分组作为AES算法的初始密钥,实现了一次一密;通过用动态密码对明文修补,实现密文与明文的长度相同;通过减少加密轮次,降低其时间复杂度,从而使其在数字图书馆数据加密系统中的应用可行。计算机仿真结果验证了该算法的正确性以及密文对密钥的高度敏感性。  相似文献   
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