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1.
本文论述了植物雄性不育的类型、原因、诱导和应用,总结了国内外在这方面的研究成果。重点对植物雄性不育的类型给以分析,从而丰富了遗传多样性的内容,展示了雄性不育理论和应用研究的光明前景。  相似文献   
2.
With unique characteristics such as high surface area, capacity of various functionalization, low weight, high conductivity, thermal and chemical stability, and free radical scavenging, carbon nanomaterials (CNMs) such as carbon nanotubes (CNTs), fullerene, graphene (oxide), carbon nanohorns (CNHs), and their derivatives have increasingly been utilized in nanomedicine and biomedicine. On the one hand, owing to ever-increasing applications of CNMs in technological and industrial fields as well as presence of combustion-derived CNMs in the ambient air, the skepticism has risen over the adverse effects of CNMs on human being. The influences of CNMs on cardiovascular system and cardiovascular diseases (CVDs) such as atherosclerosis, of which consequences are ischemic heart disease and ischemic stroke, as the main causes of death, is of paramount importance. In this regard, several studies have been devoted to specify the biomedical applications and cardiovascular toxicity of CNMs. Therefore, the aim of this review is to specify the roles and applications of various CNMs in atherosclerosis, and also identify the key role playing parameters in cardiovascular toxicity of CNMs so as to be a clue for prospective deployment of CNMs.  相似文献   
3.
Vegetable crops in the southeastern United States are commonly grown on plastic mulch with two crop cycles produced on a single mulch application. Field trials were conducted in 2013 and 2014 in two locations to evaluate the efficacy of fluensulfone for controlling Meloidogyne spp. when applied through drip irrigation to cucumber in a tomato–cucumber double-cropping system. In the spring tomato crop, 1,3-dichloropropene (1,3-D), fluensulfone, and a resistant cultivar significantly decreased root galling by 91%, 73%, and 97%, respectively, compared to the untreated control. Tomato plots from the spring were divided into split plots for the fall where the main plots were the spring treatment and the subplots were cucumber either treated with fluensulfone (3.0 kg a.i./ha. via drip irrigation) or left untreated. The fall application of fluensulfone improved cucumber vigor and reduced gall ratings compared to untreated subplots. Fluensulfone reduced damage from root-knot nematodes when applied to the first crop as well as provided additional protection to the second crop when it was applied through a drip system.  相似文献   
4.
蜜蜂化学生态学化学通讯与信息素研究进展   总被引:4,自引:0,他引:4  
孟宪佐 《生态学报》1997,17(1):83-90
概括了蜜蜂化学生态学的主要研究内容和领域,重点评述了蜂群内的化学通讯和蜜蜂信息素研究的进展。迄今,已经鉴定的蜂王信息素有9-氧化-(反)-2-癸烯酸(9-ODA),R(一)-9-羟基癸烯酸R(一)-9HDA),S(+)-9-羟基癸烯酸(S(+)-9HDA),对-羟基苯甲酸甲酯(HOB)和4-羟基-3-甲本基乙醇(HVA)等5种;工蜂那氏信息互膛牛醇,橙花醇,(反,反)-法尼醇,(反)柠檬醛,(顺)  相似文献   
5.
近年来定量蛋白组学技术迅速发展,目前常用的有双向荧光差异凝胶电泳、同位素亲和标记、15N同位素标记、同位素标记相对和绝对定量和细胞培养条件下稳定同位素标记技术等。同位素标记相对和绝对定量技术以其高通量、高灵敏度、高重复性、高动态检测限和能对各种复杂样品进行相对和绝对定量研究等优势而备受研究者青睐,目前已发展到在同一实验中分析8组样品,增加了实验设计的灵活性。我们就同位素标记相对和绝对定量技术在定量蛋白组史中的地位作用、研究策略,以及在病毒致病机制研究和医药临床相关问题中的应用做简要综述。  相似文献   
6.
以木质纤维素为原料的生物炼制不仅需要考虑到纤维素和半纤维素,同时也需要考虑到木质素的利用,以提高木质纤维素炼制的整体经济效益。利用汽爆处理的玉米秸秆为原料,通过优化碱提取的温度以及碱浓度,获得木质素得率较高,糖含量较少的提取液,同时该提取液经过浓缩后直接部分替代苯酚与甲醛反应制备酚醛泡沫。结果表明:当提取温度120℃,碱浓度1%,固液比1∶10,提取时间2 h,木质素的提取率达到79.67%。由该提取液替代苯酚制备的酚醛泡沫随着替代率的增加,其泡沫的密度逐渐增加,其压缩强度相对于纯酚醛泡沫也得到了提高。而木质素的加入并没有显著影响其热导率以及阻燃性能,同时由于其利用较为低廉的可再生资源木质素替代不可再生的苯酚原料,成本低,环保性好,具有更好的市场应用前景。采用木质素提液直接制备酚醛泡沫材料,工艺流程简单;增加了副产物木质素的经济价值,提高了整个木质纤维素炼制的经济性。  相似文献   
7.
8.
目的:探讨阴道镜直视宫颈多点活检与传统宫颈活检对宫颈疾病诊断的临床应用及影响因素研究。方法:选择2015年5月至2016年3月我院妇科收治的宫颈疾病患者86例,按照随机数表法,将患者分为对照组和研究组,每组43例。对照组患者进行常规的宫颈活检,研究组患者采用阴道镜直视宫颈多点活检。对比两种检查方法与病理检查结果的检出率,并比较两种检查方法的漏诊率,另外考察影响阴道镜直视宫颈多点活检漏诊率的相关因素。结果:与病理检查结果相比,除宫颈炎和宫颈癌外,研究组对其他类型宫颈疾病的检出率及总检出率明显高于对照组(P0.05);除宫颈癌外,研究组对各种宫颈疾病的漏诊率与对照组相比明显下降(P0.05);年龄超过50岁,高级别的CIN类型、标本个数的减少及宫颈微小病变都可能升高阴道镜直视宫颈多点活检漏诊率。结论:与传统宫颈活检相比,阴道镜直视宫颈多点活检对宫颈疾病的诊断具有较高的诊断率,并且漏诊率较低,可以适当增加活检的样本个数来降低漏诊率,从而尽早发现并进行有效治疗,值得在临床上推广应用。  相似文献   
9.
Biochar amendments to soils had aroused much interest for having potential for greenhouse gas mitigation, soil improvement and increased crop productivity. However, little attention had been focused on the influence of biochar amendments on herbivorous insect pests. This study investigated whether a biochar amendment affected developmental and reproductive performances of the rice brown planthopper (Nilaparvata lugens) feeding on rice plants. The biochar from the pyrolysis of wheat straw was used for treatments of soils (from a fallow rice field), and the treated soils were applied to grow rice seedlings in small vials, in which Nlugens life history was observed. The nymphal development time was delayed and nymph‐to‐adult survival decreased with a high level of 200 g/kg biochar application. Herbivore lifetime fecundity decreased with increasing amounts of biochar, from 256 eggs under the control down to 69 eggs under the high level (200 g/kg) of biochar application. Egg‐hatching rate significantly decreased at the highest biochar level (200 g/kg), compared to the other lower biochar levels. Our results suggest that biochar amendment to rice fields may have negative impacts on the rice brown planthoppers when applied at level of 200 g/kg of soil.  相似文献   
10.
The ability of the classic tumour‐suppressive let‐7 family to inhibit carcinogenesis, tumour progression, recurrence and pluripotency of cancer stem cells has generated significant interest in the field of cancer research. Through suppressing and degrading downstream‐targeted mRNAs, let‐7 affected most aspects of cell biology. It is perplexing how let‐7 affects oncogenesis, as the large influx of new miRNAs and other kinds of non‐coding RNAs are continuously defined. In this review, we delineate the complex functions of let‐7 and discuss the future direction of let‐7 research.  相似文献   
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