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91.
A retrospective histopathologic study of primary glaucoma in the Norwegian Elkhound was undertaken with the study of 9 clinically normal eyes and 22 glaucomatous eyes. All glaucomatous eyes showed goniodysgenesis as manifested by pectinate ligament dysplasia and/or trabecular meshwork dysplasia. Cystic degeneration of the iridociliary epithelial and/or peripheral retina was present in a high percentage of both normotensive and glaucomatous eyes. Utilizing the scheme proposed by Smith et al. (Veterinary and Comparative Ophthalmology 1993; 3: 16-28) the morphology of this disease in the Norwegian Elkhound would be classified as an open-angle, closed-cleft glaucoma, with histopathologic alterations of the outflow pathway similar to that described in other breeds with primary glaucoma. 相似文献
92.
采用氮气和氧气2种冷离子体改性木材表面,利用水和二碘甲烷测试不同放置时间下木材表面接触角,根据YGGF方程计算表面自由能及其色散力和极性力。结果表明;经氧气和氮气冷等离子体改性后的木材表面自由能显著提高,1h后测得其表面自由能分别提高54.23%和54.41%;2种等离子体改性后表面自由能都随放置时间的延长逐渐降低,6~10d内活性降低迅速,14~21d后接近于改性前水平;氧气处理后木材表面接触角更小,处理效果更好。 相似文献
93.
目的研究不同菱壳水和乙醇提取物的抗癌活性。方法采用Folin比色法测定不同品种菱壳提取物中多酚的含量,通过MTT法测定二角菱壳、四角菱壳的水提取物、醇提取物对肺癌A549细胞生长抑制作用。结果四角菱壳多酚含量高于二角菱壳,醇提物多酚含量高于水提物;二角菱壳醇提取物对肺癌A549细胞的抑制率高于水提物,差异具有统计学意义(P<0.01);四角菱壳水提物对抑制率高于二角菱壳水提物肺癌A549细胞的生长,差异具有统计学意义(P<0.01)。结论菱角壳提取物对肺癌A549细胞生长具有较强的抑制作用,且菱角壳的醇提取物优于水提取物,四菱角壳优于二角菱壳。 相似文献
94.
95.
The objective of this study was to establish a technique for radiographic examination of the coxofemoral joint and adjacent bony structures in standing cattle. Left (or right) 30° dorsal-right (or left) ventral radiographic views of the coxofemoral joint region of standing cattle (n = 10) with hind limb lameness were evaluated retrospectively. In addition, an experimental study of oblique laterolateral views of the coxofemoral joint region of a bovine skeleton at angles of 15-45° was carried out to determine the optimal position for visualization of the hip region. In the 10 clinical patients, the bodies of the ilium and ischium, the acetabulum and proximal third of the femur could be assessed. Six of these cattle had fractures of the body of the ilium and body of the ischium, five with and one without involvement of the acetabulum, two had craniodorsal and one caudoventral luxation of the femur and one had a femoral neck fracture. The described laterodorsal-lateroventral radiographs of the hip region in standing cattle were suitable for assessing the coxofemoral joint, the proximal aspect of the femur and parts of the ischium, ilium and pubis. After testing the optimal angle on the skeleton, it was seen that distortion and superimposition were minimized by positioning the X-ray beam at an angle of 25° to the horizontal plane. It can be concluded that the described technique improves the evaluation of injuries of the coxofemoral region in cattle. With the appropriate angle, the technique can also be applied in recumbent cattle. 相似文献
96.
This paper calibrates the advanced injector angle and EGR of a four-in-line pressure engine on the specialized test stand, which makes the NOx achieved the standard of Euro IV. Then an experiment study of the diesel oxidation catalyst (DOC) and the particulate oxidation catalyst (POC) are made. Both make the diesel engine emission achieving the Standard of Euro IV. This experiment study shows a kind of method that realizing diesel engine emission standard of Euro IV, and concludes the character and law of the method. 相似文献
97.
基于交角的林木竞争指数 总被引:15,自引:0,他引:15
建立基于交角的林木竞争指数(u_a_CIi),该指数能够同时表达出竞争木对对象木的上方遮盖和侧翼挤压。该指数取值范围为[0,1),无量纲,指数值越大,表明树体越小,所承受的竞争压力越大,清晰直观地表达林木在林分中所处的相对竞争态势。从理论上阐明大的竞争邻体比小的竞争邻体对对象木有更大影响,不仅反映在上方的遮盖也体现在侧方的挤压中。该指数与林木大小的相关性明显高于常用的HEGYI竞争指数。在测量技术飞速发展的今天,该竞争指数将具有很大的应用前景。 相似文献
98.
99.
《Southern Forests》2013,75(4):317-327
Regression analyses identified ‘Growth Days’ (an index expressing site moisture availability) as the only site variable contributing significantly to the prediction to wood density (R2 = 0.57), whereas the model predicting grain angle included only ‘Altitude’ (R2 = 0.60). These results surfaced during an investigative study to quantify various sources of variation in wood properties and to quantify the effect of a number of site factors on wood properties of Pinus patula grown in the Mpumalanga escarpment area of South Africa. For this purpose, 10 trees were sampled from each of 17 diverse sites for wood property analyses. The effects of site, distance from the pith and differences between trees within site on wood density, transverse shrinkage, grain angle and dynamic modulus of elasticity were investigated. The site factors considered included a wide variety of soil and climatic factors. The effect of radial distance from the pith and differences between individual trees within sites were highly significant, accounting for most of the variation in wood properties. Although the effects of a number of site factors were statistically significant, they generally explained relatively small but important variation in wood properties among sites. The study not only quantified the effects of important sources of variation on a few key wood properties, but it also revealed that the extent of differences between sites can be explained in terms of some specific site factors. It is envisaged that the results will contribute significantly towards the refinement of current forest site classification systems for improved decision-making with respect to wood quality in intensively managed plantation systems. 相似文献
100.
《Plant Production Science》2013,16(1):24-30
AbstractTo evaluate the effect of inclination angle of the leaf on the leaf injury of rice by O3, we examined the effect of a 5-hr exposure to 0, 0.1, 0.3 cm3 m-3 O3, abbreviated as O0, O0.1 and O0.3, respectively, of the flag leaf using natural-light gas-exposure chambers. The middle portion of the flag leaf was set horizontally using lead weights (H plant) and it was compared with a non-treated, erect leaf (E plant). Gas exchange and chlorophyll fluorescence were measured immediately before, immediately after, and 1 and 3 d after the start of the exposure. The net photosynthetic rate, stomatal conductance and operating quantum efficiency of photosystem II (Fq’/Fm’) were decreased by the exposure to O3. Furthermore, the inhibitory effects of O0.1 and O0.3 on the H plants were severer than those on the E plants. The maximum quantum efficiency of photosystem II (Fv/Fm) in the leaf of H plants decreased immediately after exposure to O3. These results indicate that the weaker inhibitory effect of O3 on the erect leaf depends on the lower light intensity at the leaf surface, rather than the horizontal leaf position.Key words: Ascorbic acid, Chlorophyll fluorescence, Gas exchange, Leaf inclination angle, Oryza sativa, O3, Quantum efficiency. 相似文献