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61.
据各大城市提供的数据分析,大树移植的成活率仅在50%左右,这个问题日益受到有关专家及园林建设者们的重视。如何提高大树移植的成活率?笔者经过多年的实践,认为,大树移植是一项系统的工程,需要严格的技术要求和具体的养护措施,只有遵循自然生长规律,才能收到较好的成活效果。 相似文献
62.
Nuh Kl Nihat Toplu Ahmet Aydoan Rahime Yaygngül ule Yurdagül
zsoy 《Veterinary ophthalmology》2010,13(Z1):100-102
A 15‐year‐old male dromedary camel with a history of chronic severe keratoconjunctivitis and corneal mass in the left eye of 6 months’ duration was referred to the Veterinary Medical Teaching Hospital at Adnan Menderes University. A superficial keratectomy was performed and biopsy material submitted for histopathology. The diagnosis was corneal papilloma. There has been no recurrence of the neoplasm to date (6 months, 1 year). Corneal papilloma has not been reported previously in camels and seems to be associated with papillomavirus. 相似文献
63.
分析重庆市涪陵区种植球根花卉的优势所在和效益,并提出发展球根花卉产业的方向和困难。 相似文献
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Ochiai N Fujimura M Motoyama T Ichiishi A Usami R Horikoshi K Yamaguchi I 《Pest management science》2001,57(5):437-442
Osmotic-sensitive (os-1) mutant alleles in Neurospora crassa exhibit resistance to dicarboximides, aromatic hydrocarbons and phenylpyrroles. We have previously reported that the os-1 mutants can be classified into two groups based on their resistance to fungicides and osmotic stress: type I, which are highly resistant to iprodione and fludioxonil but moderately sensitive to osmotic stress, and type II, which are highly sensitive to osmotic stress but moderately resistant to fungicides. To explain the mechanism of resistance to these fungicides, we cloned and sequenced the mutant os-1 genes that encode putative osmo-sensing histidine kinase. Within the os-1 gene product (Os1p), the type I strains, NM233t and Y256M209, carried a stop codon at amino acid position 308 and a frameshift at amino acid position 294, respectively. These mutation sites were located on the upstream of histidine kinase and the response regulator domains of Os1p, strongly suggesting that type I strains are null mutants. The null mutants, NM233t and Y256M209, were highly resistant to iprodione and fludioxonil; thus Os1p is essential for these fungicides to express their antifungal activity. The amino acid changes in Os1p, 625Pro from Leu, 578Val from Ala, and 580Arg from Gly were found in the type II strains, M16, M155-1 and P5990, respectively. Os1p is novel in having six tandem repeats of 90 amino acids in the N terminal. Each amino acid change of the type II strains was located on the fifth unit of six tandem repeats. Type II strains with single amino acid changes were more sensitive to osmotic stress than the null mutants (type I), indicating that the amino acid repeats of Os1p were responsible for an important function in osmo-regulation. 相似文献
67.
O型口蹄疫病毒VP1 T细胞与B细胞表位基因双拷贝串联表达产物的免疫应答 总被引:1,自引:0,他引:1
以一株O型口蹄疫病毒(FMDV)外壳蛋白VP1基因为模板,合成与细胞免疫及体液免疫相关抗原表位肽基因:21-40肽(20AA)和141-160肽(20AA)基因序列,运用基因工程技术构建了含有串联结构21-40(20AA)~141-160(20AA)~21-40(20AA)~141-160(20AA)的2020-2020VP1融合基因表达载体r2020-2020,转化宿主菌BL21(DE3)RIL后诱导表达,表达产物经SDS-PAGE及Western Blot分析显示重组融合蛋白的分子量约为18Ku.动物实验表明,较小剂量的融合蛋白就能诱导豚鼠产生特异性T淋巴细胞增殖反应及抗FMDV中和抗体,证明该融合蛋白可同时激活细胞免疫及体液免疫反应,具有开发成为抗FMDV疫苗的应用价值. 相似文献
68.
Total labor time on paddy rice has been decreasing year by year with the development and introduction of appropriate herbicides, especially ‘one‐shot' herbicides. However, in the case of application of granules, it is still difficult for a farmer to apply herbicides while carrying heavy power backpack sprayers. New formulation recipes and different application technology such as a throw‐in type formulation on jumbo granules or flowable has improved heavy workloads in comparison with granule application by using heavy power backpack sprayers. In addition, other advantageous points such as application volume and elimination of the drift problems of this new application technology were introduced and confirmed. As a result of this introduction, these formulations were used in 830 000 ha and reached 30% of the total treatment area in paddy rice in 2000. 相似文献
69.
新疆哈纳斯自然保护区地衣群落的聚类分析 总被引:3,自引:0,他引:3
我们根据多年的实地调查结果并采用聚类分析方法对分布在哈纳斯国家级自然保护区的地衣群落进行了研究。结果表明分布在该地区的地衣种类有 10 3种 ,他们分别属于 2 0科 ,4 0属。地衣物种形成了 6种群落。同时发现该地区地衣对基物形成专一性 ,它们的基物包括 :树皮、藓丛、藓土、草地、石面、地面、土层、石浮土等。 相似文献
70.
This paper reports the results of a 2 × 2 factorial experiment on bush snap beans ‘Oregon 1604’. The treatments were 2 contrasted irrigation regimes and 2 contrasted plant densities, and were applied in 1978 and repeated in 1979. Data were collected on the number of flowers and pods, and pod size, at each node of the terminal inflorescence (6-T) of the main stem, and at each node of the oldest inflorescence (2-A) at Node 2. High and low plant densities were 45 and 18 plants m?2 in 1978 and 54 and 33 plants m?2 in 1979. High temperatures, frequently above 32°C, prevailed during bloom and pod development in 1978, but for the most part occurred only during the week prior to bloom in 1979. Inflorescences 6-T and 2-A usually formed 4 and 3 RN's, respectively, in 1978 and 3 and 2 RN's in 1979. The flowers at the proximal nodes of each inflorescence all opened within a few days of one another (duration of flowering at proximal nodes between 3 and 5 days); the flowering-periods of adjacent nodes overlapped, and the flowering period increased acropetally within the inflorescence (duration of flowering at distal nodes between 7 and 13 days). In general, number of flowers, pods formed, pods harvested and percent set decreased acropetally within each inflorescence. The rate of acropetal decline was lessened by high irrigation or low plant density. In both years, high irrigation increased the percent set of all RN's of the 2-A inflorescences, but few other consistent effects between years were observed. The 2 most proximal RN's together produced 93% or more of the yield of each inflorescence. High irrigation significantly increased the total number of pods harvested from these RN's of inflorescences 6-T and 2-A, and low density had a similar effect on 2-A. 相似文献