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991.
Tropical Animal Health and Production - Non-additive genetic effects are important to increase the accuracy of estimating genetic parameters for growth traits. The aim of this study was to estimate...  相似文献   
992.
Tropical Animal Health and Production - Genetic structure and genetic diversity levels of indigenous Iranian sheep breeds are not clear, despite the interest this region has in itself as an...  相似文献   
993.
为探究灌溉模式与种植方式对青贮玉米(Zea mays L.)生长、产量和经济效益的影响,本研究在河西地区设置3个种植方式(S:青贮玉米单播;SM:青贮玉米与秣食豆(Glycine max L.Merr)混播;SL:青贮玉米与拉巴豆(Lablab purpureus L.Sweet)混播)和6种灌溉模式(W1:6叶期灌溉;W2:6叶期和12叶期灌溉;W3:6叶期和散粉期灌溉;W4:6叶期、12叶期和散粉期灌溉;W5:6叶期、散粉期和灌浆期灌溉;W6:6叶期、12叶期、散粉期和灌浆期灌溉)进行田间试验。结果表明:SM、SL和S种植下玉米的株高、茎粗和相叶绿素含量差异不显著,但SM和SL较S显著提高了叶面积指数;SM和SL的鲜干草产量和净收益显著高于S;在灌浆期和收获期,W5和W6的株高、茎粗、相对叶绿素含量和叶面积指数显著高于W1;W5、W6的鲜干草产量和净收益显著高于W1,W2和W3。所有处理中,SM-W5获得了最高的干草产量和净收益,是河西地区青贮玉米适宜的栽培模式。  相似文献   
994.
995.
Adrenergic receptor (AR) expression has been demonstrated at several sites of primary and metastatic tumour growth and may influence proliferation, survival, metastasis and angiogenesis. AR antagonists like propranolol and carvedilol inhibit proliferation, induce apoptosis and synergize with chemotherapy agents in some cancers. Radiation resistance is mediated in many cells by upregulation of pro‐survival pathways, which may be influenced by ARs. Studies evaluating AR antagonists combined with radiation are limited. The purpose of this study was to determine the effect of propranolol and carvedilol on viability and radiosensitivity in sarcoma cell lines. The hypothesis was that propranolol and carvedilol would increase radiosensitivity in four primary bone sarcoma cell lines. Single agent propranolol or carvedilol inhibited cell viability in all cell lines in a concentration‐dependent manner. The mean inhibitory concentrations (IC50) for carvedilol were approximately 4‐fold lower than propranolol and may be clinically relevant in vivo. Immunoblot analysis confirmed AR expression in both human and canine sarcoma cell lines; however, there was no correlation between baseline AR protein expression and radiosensitivity. Short duration treatment with carvedilol and propranolol did not significantly affect clonogenic survival. Prolonged exposure to propranolol and carvedilol significantly decreased the surviving fraction of canine osteosarcoma cells after 3Gy radiation. Based on our results and possible in vivo activity in dogs, further studies investigating the effects of carvedilol on sarcoma are warranted.  相似文献   
996.

The study was carried out to determine phenolic compounds, antioxidant activity, total lipids, saturated fatty acids, unsaturated fatty acids, and volatile organic compounds (VOCs) of 18 different walnut (Juglans regia L.) cultivars and genotypes grown in Usak province, Turkey. The biochemical compounds were identified for each cultivar and genotype and a comparative evaluation was carried out. The results showed that most of the biochemical compounds are significantly varying among each other (p?<?0.05). The existence and abundance of the biochemical compounds in the cultivars and genotypes have not only found to be a cause of differentiation, but they have been important parameters for the similarities among the cultivars and genotypes. Total phenolic content and antioxidant activity ranged from 750.67 to 1245.64?mg GAE ml?1 and from 42.46 to 56.50% in kernels, respectively. The highest contents of the phenolic compounds were noted from gallic acid (11991?mg kg?1), ellagic acid (1057.16?mg kg?1), catechin (425.4?mg kg?1), and rutin (216.6?mg kg?1), as an average of all cultivars and genotypes. The highest lipid contents were noted from ‘Franquette’ and ‘Fernette’ as 64.28% and 63.26%, respectively, while the lowest content was noted from ‘Oguzlar 77’ (52.52%). A total of 42 VOCs were described from the 18 different walnut cultivars and genotypes. Overall, results showed that the phenolic profiles, fatty acids composition, and VOCs play an important role in similarities and diversities among the cultivars. According to the results, 7 different clusters were developed from the 18 cultivars and genotypes. Herein, ‘Fernor’, ‘Maras 18’, ‘Arslan Local Type’ and ‘Cisco’ cultivars were found to have the lowest biochemical compositions. The superior cultivars or genotypes, in terms of the abundance of the biochemical composition, were found to be ‘Gulizar Hanim Type’, ‘Lara’, ‘Pedro’, ‘Tulane’, ‘Fernette’, ‘Balkan’ and ‘Franquetta’, where they were found to develop 3 clusters by 1:3:3, respectively.

  相似文献   
997.
 采用单因素试验和响应面分析等方法优化解淀粉芽胞杆菌ZF57的发酵工艺。得到解淀粉芽胞杆菌ZF57发酵的最优条件为山梨醇10 g·L-1、棉籽饼粉17 g·L-1、NaH2PO4 0.5 g·L-1、Na2HPO4 0.4 g·L-1,初始pH 7.0、装液量80 mL/250mL三角瓶、接种量2.1%、培养温度30℃、转速180 r·min-1、发酵时间32 h,此时含菌量达到3.8×108 CFU·mL-1,较优化前提高了80%。明确了解淀粉芽胞杆菌微粉剂的最佳配方为解淀粉芽胞杆菌母粉50%,白炭黑10%,分散剂木质素磺酸钠1%,表面活性剂十二烷基硫酸钠4%,保护剂羧甲基纤维素钠1%,硅藻土补足至100%。该制剂含菌量为3.26×109 CFU·mL-1,平均粒径8.31 μm,分散指数98.16%,浮游性指数85.37,含水率1.42%,坡度角68°,各项检测结果均符合标准。解淀粉芽胞杆菌ZF57微粉剂对黄瓜棒孢叶斑病的田间防治效果高达97.12%。  相似文献   
998.
<正>果胶杆菌(Pectobacterium)可引起马铃薯、黄瓜等多种作物的软腐病,具有十分广泛的寄主范围。近年来,随着甜瓜种植规模的不断扩大,山东、河北、辽宁等多个甜瓜种植区出现茎秆严重腐烂的现象,发病初期甜瓜茎秆出现褐色病斑,然后逐渐腐烂,导致植株整株死亡,造成了严重的经济损失。本研究对山东寿光、昌乐和莱西疑似甜瓜茎软腐病的病株进行调查采样(图1-A、B),通过病原菌分离鉴定和致病性测定,为该地区细菌病害的病原分析提供实验参考。  相似文献   
999.
Fig (Ficus carica) is an exotic deciduous plant that is grown worldwide. Fungal diseases pose a major threat to fig plants, affecting their fruit quality and production. This study was conducted to characterize the fungal isolates associated with leaf blight, stem rot and fruit rot of F. carica in Malaysia through morphological analysis, DNA sequencing, multigene phylogenetic analysis and pathogenicity tests. From September 2018 to March 2019, 30 blighted leaves and 30 rotted stems and fruits of F. carica were collected from several nurseries in Malaysia. Thirty fungal isolates that belonged to Lasiodiplodia theobromae (27 isolates) and L. brasiliensis (three isolates) were identified based on morphological characteristics, comparison of DNA sequences and phylogenetic analysis of the internal transcribed spacer (ITS), elongation translation factor 1-α (tef1-α), β-tubulin (tub2) and DNA-directed RNA polymerase II subunit (rpb2). Among the 27 isolates of L. theobromae, nine isolates were obtained from leaves, eight isolates from stems and 10 isolates from fruits, whereas the three isolates of L. brasiliensis were obtained from stems (two isolates) and a leaf (one isolate). The results of pathogenicity tests revealed that L. theobromae and L. brasiliensis isolates were responsible for leaf blight and stem rot of F. carica, whereas fruit rot was caused by L. theobromae isolates. The present study highlighted two different species, L. theobromae and L. brasiliensis, as the causal agents of leaf blight and stem rot of F. carica. Additionally, L. theobromae caused fruit rot of F. carica in Malaysia.  相似文献   
1000.
 建立了土壤中芸薹根肿菌荧光定量PCR(qPCR)快速检测及风险预警体系。确定了芸薹根肿菌qPCR检测的特异性引物PbF/PbR,对根肿菌质粒DNA的检测灵敏度为1.612×10-6 ng·μL-1,比普通PCR高出1 000倍;对土壤和基质中芸薹根肿菌孢子的最低检测下限均为10 个·g-1,而土壤和基质带菌的发病阈值分别为100和1 000 个·g-1,高于该浓度时根肿病发生风险大。本研究建立的芸薹根肿菌qPCR技术体系检测下限远低于发病阈值,可以快速、准确、定量地检测出采自四川绵阳、湖北恩施、江苏无锡、山东青岛、辽宁沈阳、山西运城、内蒙古巴彦淖尔和宁夏固原等8个地区的27份田间土壤中芸薹根肿菌的数量,实现对十字花科根肿病的监测预警,为制定产前病害防控方案提供依据。  相似文献   
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