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1.
玉米不同耐密植品种茎秆穿刺强度的变化特征   总被引:17,自引:1,他引:17  
以耐密抗倒性不同的品种(稀植大穗品种JK 518和JK 519、耐密抗倒品种XY335和CS 1;中等耐密品种ND 108)为材料,设5个密度处理,研究玉米茎秆的穿刺强度(RPS)的变化特点及其对群体种植密度的响应。结果表明玉米茎秆穿刺强度随生育期递进而增强,不同耐密性品种间随种植密度变化有较大差异。茎秆基部节间的穿刺强度随群体密度增加呈线性递减。茎秆节间RPS随着节位的上升而呈二次函数递减;不同耐密性品种间RPS以抽雄-吐丝期差异明显,以穗位以下节间,尤其第3~6节间表现差异较大。玉米抽雄前茎壁增厚早、  相似文献   
2.
成人胸12及腰1椎体高度,前后缘差及楔变指数X线的正常值   总被引:1,自引:0,他引:1  
对400例成人第12胸椎(T(12))及第1腰椎(L_1)X线侧位片测量的结果:(1)椎体侧位的高度正常值:T_(12)椎体前缘男性为29.5±4.9mm,女性为28.1±4.4mm;后缘男性为32.7±5.7mm,女性为30.3±5mm。L_1椎体前缘男性为30.2±5.1mm,女性为29.1±4.1mm;后缘男性为33.8±4.6mm,女性为31.6±4.2mm。(2)T_(12)和L_1椎体侧位的高度差正常值上限男性为6.5mm,女性为5.4mm;楔变指数正常值下限男性为0.79,女性为0.83。(3)T_(12)及L_1推体侧位"楔变"为正常表现。  相似文献   
3.
以南方高海拔地区栽培的甜樱桃品种"美早"和"萨米脱"为试材,利用质构仪质地多面分析法(TPA)和整果穿刺法研究其贮藏过程中质地特性的变化。结果表明,贮藏过程中两个品种樱桃果肉的硬度与弹性、咀嚼性,咀嚼性与弹性均呈极显著正相关,且随贮藏时间的延长,果肉硬度、弹性、咀嚼性和果皮强度下降,果皮韧性增强,而果肉凝聚性和回复性则先上升后下降。贮藏42d后",美早"甜樱桃果肉的硬度、咀嚼性、凝聚性和回复性显著高于"萨米脱"甜樱桃,同时保持较低的果皮韧性,说明其更耐贮藏。  相似文献   
4.
Maize rayado fino marafivirus (MRFV) was mechanically transmitted to kernels of three Costa Rican maize cultivars by the vascular puncture technique. A transmission rate of up to 43.2% was obtained for cultivar HC-57. The rate of MRFV transmission to maize was possibly affected by the morphology of the kernel, which may influence physical access to the vascular tissue after water imbibition. Transmission to maize was confirmed by western blot and immunosorbent electron microscopy. By slight modifications of the procedure, MRFV was also transmitted to barley. This is the first report of MRFV infecting a species outside the supertribe Andropogonodae. Virus infection and replication in barley were confirmed by RT-PCR detection of MRFV RNA and by detection of the virus by ELISA.  相似文献   
5.
The Chato Murciano pig is a breed catalogued as a Special Protection breed in danger of extinction. At present it is commonly reared in an intensive system. We have studied the mineral composition and other characteristics of its carcass and meat. Samples from the Musculus longissimus lumborum were taken from a total number of 43 animals, divided into two groups, Chato Murciano and Chato Murciano crossed with Iberian, reared in a conventional indoor system. The resulting meat of the Chato Murciano pig and its cross with Iberian was especially rich in iron and copper, rich in phosphorus, and marginally poor in calcium and sodium. The evolution of the pH of the carcass was that of pigs which do not produce PSE (pale, soft and exudative) meat. Some relevant positive correlation coefficients between minerals (P ≤ 0.05) have been found.  相似文献   
6.
An increasing proportion of canine patients are presented with chronic thoracolumbar back pain and without compressive spinal lesions. In humans, spinal perineural infiltrations have been reported to have a favorable effect on pain control. The purpose of this prospective cadaver study was to describe the dispersal pattern of injectate following CT‐guided spinal perineural infiltration in the canine thoracolumbar region. Seven fresh canine cadavers were first scanned using multislice CT and then CT‐guided spinal perineural infiltration was performed at 42 sites from T13/L1 to L6/L7. The injectate for each site was a mixture of new methylene blue and iodinated contrast medium. Immediately following CT‐guided injection, cadavers were frozen, cut, and dissected macro‐ and mesoscopically (using a magnifying glass) to identify anatomic structures that were infiltrated. In the majority of sites (64.3%), complete epidural and hypaxial staining of spinal nerve components (including the spinal ganglion, trunk, and ventral branch) was successfully achieved. However, no (11.9%) or unpredictable staining (9.5%) of nervous tissue occurred in some sites despite careful CT guidance and the application of relatively large volumes of injectate. Optimal results were achieved when the needle tip was positioned periforaminally ventral to the cranial contour of the cranial articular process. Findings from this ex vivo study indicated that CT‐guided spinal perineural infiltration is feasible for testing in the canine thoracolumbar region and that successful nerve tissue infiltration would likely occur in the majority of sites. Future in vivo studies are needed to determine the safety and efficacy of this technique.  相似文献   
7.
8.
【目的】研究化控剂(30%胺鲜酯·乙烯利水剂以下称玉黄金)对春玉米茎秆显微结构及抗折强度的影响。【方法】选取京农科728和金农738为材料,测定不同种植密度下喷施玉黄金后春玉米茎秆抗折强度,利用光学显微镜观察其茎节的显微结构,对维管束各项显微结构与茎秆抗折强度进行相关分析及通径分析。【结果】维管束数目对茎秆抗折强度的直接影响最大,且呈极显著负相关为-0.760;与木质部面积呈极显著正相关为0.970;与单个维管束平均面积、维管束最大直径和表皮细胞厚呈显著正相关分别为0.661、0.659和0.632。【结论】京农科728和金农738在不同种植密度下,喷施浓度为200 mg/L的玉黄金后茎秆单位面积内维管束数目减少、表皮厚度增厚、维管束最大直径最大、抗折强度提高,抗倒性增强。  相似文献   
9.
目的分析通过刺络拔罐配合静力练习治疗急性踝关节扭伤的临床疗效。方法收集2009年-2013年病例共71例,根据治疗方案随机分为观察组36例、对照组35例,观察组采用刺络拔罐配合静力练习治疗,对照组采用单纯刺络拔罐治疗。7 d为1个疗程,1个疗程后观察疗效,2个月后复查或随访患者,评价踝关节Kofoed评分。结果两组治疗后临床疗效比较,差异有统计学意义(P<0.05)。2个月后评价踝关节Kofoed评分,观察组与对照组比较,差异有统计学意义(P<0.05)。结论急性踝关节扭伤通过刺络拔罐配合静力练习治疗效果优于单纯刺络拔罐治疗。  相似文献   
10.
ABSTRACT:   The physical properties of 49 commercial kamabokos were measured by the puncture and stress relaxation tests. The principal component analysis was applied to the physical parameters of both tests, and their cumulative contribution ratios were over 90% with the first and second principal components, respectively. The comparison among the kamabokos was carried out using the synthetic physical parameters. The kamabokos produced in same area showed the peculiar distribution. The relative positional relation of kamabokos measured by the stress relaxation test was different from that by the puncture test for many of the kamabokos. Physical property evaluation using a principal component analysis is very effective for intensiveness of many measurement parameters. If much more kamabokos were measured by this method, regional characteristics of kamabokos would be clarified.  相似文献   
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