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排序方式: 共有121条查询结果,搜索用时 15 毫秒
101.
[目的]为了探明库尔勒香梨树冠内各类枝的分布及结构特征,[方法]采用树冠分格法,统计分析每个立方格内各类枝的数量及分布特征。[结果]结果表明:疏散分层形骨干枝总数为97枝,主要分布在下层与中部,开心形的骨干枝总数为94枝,主要分布在下层与中部;疏散分层形一年生枝总数为3920枝,主要分布在中层与外围,开心形一年生枝总数为3183枝,主要分布在中层与外围;疏散分层形的多年生枝总数为2184枝,主要分布在下层与外围,开心形多年生枝总数为1444枝,主要分布在中层与外围。[结论]库尔勒香梨两种树形结构,骨干枝数量与主要分布部位基本相同,一年生枝总数差异明显,但主要分布部位相同,多年生枝数量与主要分布部位均差异明显。 相似文献
102.
This paper describes a preliminary evaluation of particle-mediated bombardment via the Helios gene gun for the delivery of therapeutic genes to synovial cells in culture. A reporter gene, enhanced green fluorescent protein, was delivered to rabbit synovial fibroblasts (HIG-82) using gold particle (1.0 microm) bombardment to evaluate transfection efficiency at helium pressures of 100 and 150 psi. Transfection of cells occurred at these pressures despite some cell death. The in vitro delivery of gold particles to samples of synovial membrane and articular cartilage from a freshly euthanased dog was also studied to examine depth of penetration of gold particles (1.0 microm) at helium pressures of 250 and 500 psi. Light microscopical examination of histological sections of the synovial membrane showed that particles of gold had penetrated the lining cells of the synovium. However, no gold particles had penetrated the articular cartilage even at 500 psi. 相似文献
103.
Anwar F Bhanger MI Nasir MK Ismail S 《Journal of agricultural and food chemistry》2002,50(15):4210-4214
Seeds of Salicornia bigelovii (hybrid variety sos-10) were collected from five coastal areas of Pakistan on the Arabian Sea. Hexane-extracted oil content was 27.2-32.0%. Results of other physical and chemical parameters of the extracted oil were as follows: iodine value, 128.0-130.5; refractive index (40 degrees C), 1.4680-1.4695; unsaponifiable matter, 1.63-2.00%; saponification value, 178.6-189.0; density (30 degrees C), 0.9036-0.9074. Tocopherols (alpha, gamma, and delta) in the oil ranged up to 200 mg/kg. The S. bigelovii seed oil was found to contain high levels of linoleic acid (74.66-79.49%) and less oleic acid (12.33-16.83%). Saturated fatty acids, palmitic and stearic acids, ranged from 7 to 8.50% and from 1.24 to 1.69%, respectively. Linolenic acid (C(18:3) omega-3) was found within the range of 1.50-2.31%. The induction period (Rancimat, 20 L/h, 120 degrees C) of the crude oil was 1.40-1.70 h. Specific extinctions at 232 and 270 nm were 1.90-2.40 and 0.40-0.62, respectively. Many parameters of S. bigelovii seed oil were quite compatible with those of safflower oil. 相似文献
104.
A number of brain systems have been implicated in addictive behavior, but none have yet been shown to be necessary for maintaining the addiction to cigarette smoking. We found that smokers with brain damage involving the insula, a region implicated in conscious urges, were more likely than smokers with brain damage not involving the insula to undergo a disruption of smoking addiction, characterized by the ability to quit smoking easily, immediately, without relapse, and without persistence of the urge to smoke. This result suggests that the insula is a critical neural substrate in the addiction to smoking. 相似文献
105.
K. Tumirah S. Salamah A. Rozita U. Salmiah M. A. M. Nasir 《Wood Science and Technology》2012,46(6):1021-1031
Ultraviolet–visible Spectrophotometer method for the determination of 2-thiocyanomethylthiobenzothiazole (TCMTB) in treated wood and wood preservative was developed. The determination was done after conversion of TCMTB to 2-mercaptobenzothiazole (2-MBT). This conversion was obtained by reaction with 0.1?M cystein alkaline condition (pH 10). The extraction of 2-MBT was carried out with ethyl acetate containing 0.2% of ?-mercaptoethanol after acidification with 2?M phosphoric acid (pH 2.5). The sample absorbance was measured at 324?nm wavelength with a calibration curve range from 10 to 90?ppm of TCMTB. The Regression value, R 2, achieved was 0.9998, while the precision, RSD, was <10% (n?=?6). The recovery was in the range of 90.7–103.2% (n?=?6). The result obtained with this colorimetric procedure is comparable to the HPLC–PDA method. 相似文献
106.
107.
To evaluate the effect of corticosterone on nutrient transport, 10-week-old male chickens were grouped in 4 categories and treated as follows: sham-operated, adrenalectomised, corticosterone (4 mg/kg injected subcutaneously for 5 d) in both sham-operated and adrenalectomised. The food intake, food passage time and uptake of calcium, phosphorus and glucose were determined by standard procedures. Corticosterone administration to both sham-operated and adrenalectomised groups stimulated significantly higher food intake, delayed food passage time and increased uptake of calcium, phosphorus and glucose, as compared to sham-operated control and adrenalectomised groups. Corticosterone administration increased absorption of these nutrients significantly more in the adrenalectomised group than in the sham-operated controls. Corticosterone also significantly elevated the plasma concentrations of these nutrients. The responses to the hormone were significantly greater in adrenalectomised birds. It is concluded that corticosterone increases food intake and retention and the absorption of calcium, phosphorus and glucose in the alimentary tract. 相似文献
108.
【目的】沙01是库尔勒香梨芽变品种,果实品质良好但硬度较小不耐储运,从果实组织结构角度研究分析两个品种的硬度差异。【方法】在果实成熟期采用石蜡切片法,对2个梨品种果实角质膜、表皮细胞、单宁细胞、薄壁细胞、团围薄壁细胞及石细胞团进行观察。【结果】沙01和库尔勒香梨的角质膜厚度分别为5.44和9.44 μm;沙01的表皮细胞和单宁细胞层数较少,且纵横径比分别为0.60和0.35,细胞多表现为细长,而库尔勒香梨的细胞层数较多,且纵横径比分别为0.67和0.48,细胞多表现为短粗;沙01和库尔勒香梨果肉中的石细胞团直径分别为287.16和362.04 μm,团围薄壁细胞长度分别为343.06 和262.71 μm。果实带皮硬度与果实角质膜厚度呈极显著正相关;果实去皮硬度与单宁细胞纵横径比、石细胞团直径以及薄壁细胞长宽比呈极显著正相关,与单宁细胞横径和团围薄壁细胞长度呈极显著负相关,与薄壁细胞宽度呈显著负相关。【结论】库尔勒香梨和沙01果皮和果肉组织均存在差异,其中果皮组织中的角质膜厚度与表皮细胞层数,果肉组织中的单宁细胞层数和形状,薄壁细胞形状和大小及石细胞团直径是影响两者果实硬度差异的主要因素。 相似文献
109.
新疆杏品种(系)遗传多样性分析及DNA指纹图谱库构建 总被引:2,自引:0,他引:2
【目的】从ISSR分子标记水平分析新疆主栽杏品种(系)的遗传多样性和亲缘关系,构建新疆杏品种(系)的DNA指纹图谱数据库,为杂交育种、品种鉴定和品种分类提供理论依据。【方法】从供试样品中选取表型差异较大的6份材料对100个ISSR引物进行筛选,最终筛选出条带清晰、主带明显、多态性丰富、能够稳定重复且对品种具有较高鉴别力的ISSR特征引物,对48个新疆杏品种(系)进行扩增,采用POPGENE version 1.32软件计算多态性位点数、多态性位点百分率、观测等位基因数(Na)、有效等位基因数(Ne)、Nei’s多样性指数(H)和Shannon信息指数(I),及各材料间的Nei’s遗传相似系数(GS)和遗传距离(GD),并利用NTSYS pc version 2.10e 软件根据Nei’s遗传相似系数采用UPGMA方法进行聚类,以此分析遗传多样性和亲缘关系;利用4个引物特异位点的不同组合及Gel2.0指纹图谱自动识别系统鉴别48个新疆主栽杏品种(系),并利用Gel2.0构建主栽杏品种(系)的DNA指纹图谱库。【结果】从100个ISSR引物中筛选到重复性好、多态性丰富的4个引物作为特征引物,分别为UBC809、UBC836、UBC844和UBC850,共扩增出78个位点,其中73个为多态性位点,平均多态性位点百分率为93.13%,其中引物UBC844多态性位点百分率最高,为100.00%;48个新疆主栽杏品种(系)的观测等位基因数、有效等位基因数、Nei’s基因多样性和Shannon信息指数的平均值分别为1.9313、1.4368、0.2622和0.4028,说明各品种(系)的遗传多样性相对较丰富。‘黄肉油杏’和‘大五月杏’的遗传相似系数为0.8846,遗传距离为0.1226;‘库曼提’和‘索格佳娜丽’的遗传相似系数为0.5641,遗传距离为0.5725。将4个引物两两组合起来,可快速、准确地鉴别46个杏品种(系),只有‘辣椒杏’和‘伊犁阿克玉吕克’需要3个引物组合才能鉴别出来,利用这4个ISSR特征引物通过Gel2.0指纹图谱自动识别系统构建了48个杏品种(系)的DNA标准指纹图谱数据库。【结论】新疆主栽杏品种(系)的遗传多样性较丰富,亲缘关系相对较近,‘黄肉油杏’和‘大五月杏’的亲缘关系最近,‘库曼提’和‘索格佳娜丽’的亲缘关系最远;且ISSR标记适于新疆主栽杏品种的遗传多样性、亲缘关系分析及构建DNA指纹图谱库;指纹图谱库的建立为杏品种(系)的鉴定及品种真实性和纯度奠定了基础,为新品种登记、注册和品种知识产权保护等提供科学依据。 相似文献