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151.
152.
Objectives To determine the vitreous volume, and retinal and lens wet weights in male and female Göttingen minipigs of different age groups. Procedures Vitreous, lens and retina were isolated from fresh minipig eyes. Vitreous volume, lens and retina weight were measured and allometric scaling was utilized to predict these parameters. Results There were no gender differences in body weights or retina and lens weights in the three age groups examined in this study. For vitreous volumes, females had a significantly larger volume (approximately 10%–12%) than males in the 4–6 and 6–8 month, but not in the 8–11‐month group. The mean body weight increased from 12.2 ± 2.6 kg (4–6 months) to 19.4 ± 4.0 kg (8–11 months). In the same period, the mean vitreous volume increased from 2.00 ± 0.28 to 2.67 ± 0.31 mL, while the mean retinal and lens weights increased from 114 ± 22 to 126 ± 17 mg, and from 298 ± 26 to 392 ± 15 mg, respectively. Allometric analysis between six species for vitreous volume and four species for lens weight covering a weight range of 260‐fold was not able to estimate the vitreous volume, but it did predict the lens weight in 8–11 months minipigs. Conclusions Overall these measurements add important context to intraocular pharmacology studies, and will help in the improved design and interpretation of such experiments. 相似文献
153.
Aspergillus spp. panophthalmitis with intralenticular invasion in dogs: report of two cases
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This case series describes the ocular, clinical and histologic manifestations of disseminated Aspergillosis in two dogs. Two dogs presented for severe unilateral panophthalmitis and secondary glaucoma with positive Aspergillus spp. titers. Case 1 showed no clinicopathologic systemic symptoms of fungal dissemination, however, case 2 was affected with acute renal failure. The affected eye of case 1 did not respond to medical therapy and was enucleated for comfort. The affected eye of case 2 responded to aggressive topical and systemic medical therapies, however, the patient was euthanized for acute renal failure. Globes were collected for histologic evaluation at the time of death. Histology of both revealed panophthalmitis with presence of significant intraocular hemorrhage, multifocal fungal granulomas, retinal and optic nerve changes consistent with secondary glaucoma, rupture of the anterior lens capsule, and fungal invasion and colonization of the intralenticular space. These cases represent a unique and devastating ocular manifestation of disseminated Aspergillosis. Cases presenting with uveitis and secondary glaucoma of unknown origin, especially with confirmed or suspected lens capsular rupture, should have serologic testing for this infectious agent. 相似文献
154.
AIM: To investigate the role of JAK-STAT pathway, IL-1β and IL-6 in the PC12 cells with X-ray irradiation.METHODS: The PC12 cells were irradiated with X-ray at doses of 2, 4 and 8 Gy. After 24 h, the levels of IL-1β and IL-6 were detected by ELISA. The protein levels of p-JAK1, p-JAK2, p-STAT1, p-STAT3 and p-STAT5 were measured by Western blot.RESULTS: Compared with control group, the levels of IL-1β and IL-6 increased. The protein levels of p-JAK1, p-JAK2, p-STAT1, p-STAT3 and p-STAT5 increased with the doses of X-ray exposed.CONCLUSION: JAK-STAT signaling pathway, IL-1β and IL-6 play a role in the injury of PC12 cells with X-ray irradiation. 相似文献
155.
对X射线的吸收能力,原木木质部分与内部缺陷部分存在不同,因此在X射线底片上形成的影像也不一样,根据一定的处理识别分析,可以对原木内部缺陷的参数进行测定。利用X射线的扫描图像,提出一种原木缺陷的识别方法。 相似文献
156.
Akiko Kubo Yoshiaki Yuguchi Makoto Takemasa Shiho Suzuki Hikaru Satoh Shinichi Kitamura 《Journal of Cereal Science》2008,48(1):92-97
Micro-beam X-ray diffraction analyses were carried out on slices from wild-type rice and mutants. The method permitted the crystalline structure to be analyzed with less destruction of cells and fewer artificial effects that occur during the purification of starch from tissue and provided information concerning the localization and crystalline structure of starches distributed in the endosperm. The starch on kernel slices from the wild-type and waxy mutant, carrying a defect for the Granule-bound starch synthase I (GBSSI) gene, displayed an A-type of diffraction pattern; no difference in the crystalline patterns between starches located in the inner and outer region in a kernel were observed. A double mutant of the waxy and amylose extender (ae) mutant carrying a defect for the Starch branching enzyme IIb gene accumulated amylose-free B-type starches. The kernel slice from the double mutant of waxy and sugary1, mutated on the Isoamylase I locus, displayed an A-type diffraction pattern in the outer region and was amorphous in the inner region. A chain-length distribution analysis of polyglucans in kernels from wild-type and mutants showed that ae amylopectin had more long chains and less short chains than the wild-type and waxy amylopectin. On the other hand, the water-soluble polysaccharide in the inner region of the sugary1 endosperm had more short chains than the amylopectin in the outer region counterparts. These results indicate that branch chain length in amylopectin is crucial in determining the formation of A- and B-type starches. 相似文献
157.
《国际水土保持研究(英文)》2020,8(4):410-417
Soil erosion and associated sediment redistribution are key environmental problems in Central Argentina. Specific land uses and management practices, such as intensive grazing and crop cultivation, are considered to be significantly driving and accelerating these processes. This research focuses on the identification of suitable soil tracers from hot spots of land degradation and sediment fate in an agricultural catchment of central Argentina with erodible loess soils. Using Energy Dispersive X-Ray Fluorescence (EDXRF), elemental concentrations were determined and later used as soil tracers for geochemical characterization. The best set of tracers were identified using two artificial mixtures composed of known proportions of soil sources collected from different lands having contrasting soil uses. Barium, calcium, iron, phosphorus, and titanium were identified for obtaining the best suitable reconstruction of source proportions in the laboratory-prepared artificial mixtures. Then, these elements, as well as the total organic carbon, were applied for pinpointing critical hot spots of erosion within the studied catchment. Feedlots were identified to be the main source of sediments, river banks and dirt roads together are the second most important source. This investigation provides key information for optimizing soil conservation strategies and selecting land management practices and land uses which do not generate great contribution of sediment, preventing pollution of the waterways of the region. 相似文献
158.
受土壤有机质和微生物的影响,大部分农业土壤都有团聚体结构。团聚体内部的孔隙一般很小,与团聚体之间的水流相比,团聚体内部的水可以视为不动的。但受质量浓度梯度和分子扩散的影响,2个水体内的溶质可以相互交换。模拟溶质在具有团聚体结构土壤中运移时,溶质在以上2个水体间的交换过程常用可动-不可动水体模型来描述。土壤溶质运移涉及的参数较多,很多参数不能直接测定,要靠观测值拟合才能获得。由于不同的参数组合可以得出相同溶质质量浓度分布,因此,即使模拟结果和实验结果吻合也不能确保该模型正确描述了2个水体之间的溶质交换过程。为了深入研究这一问题,利用三维图像技术和数学模型,计算了团聚体内外溶质交换速率。结果表明,Coats-Smith模型误差很大,2个水体之间的溶质交换速率并非与其质量浓度差成正比。作为改进,提出并证明广义γ分布函数可以准确地描述团聚体内外溶质交换过程。 相似文献
159.
Among the various operations of the breadmaking chain, the impact of shaping on dough cellular structure has scarcely been studied. In this work, wheat flour dough has been laminated under different roll gap conditions δ(mm)= (2,5, 10, 20, ∞). Rheological properties were measured under large and small strains, by lubricated squeezing flow test and dynamic thermomechanical analysis, respectively. Laminating has a limited effect on the elongational viscosity of the dough. However, the minimum value of the ratio of storage modulus reached for gap δ = 5 mm suggests that gluten network structuration is improved in this case. The kinetics of porosity and shape ratio of fermenting laminated doughs were calculated from image analysis of dough follow-up during proofing. They showed that stability is improved for δ = 5 mm. Finally, Xray tomography experiments, performed on laminated rolled dough during proofing, confirmed that the main changes can be attributed to an increase of cellular homogeneity at δ = 5 mm, reflected by lower median gas cell size and less spread size distributions. 相似文献
160.
《Scandinavian Journal of Forest Research》2012,27(1):89-95
As sawmills become increasingly efficient, the importance of focusing on value recovery becomes obvious. To maximize value recovery, sawmills require the ability to sort logs according to quality. This study compares four different combinations of three-dimensional (3D) and X-ray scanning that can be used to grade logs automatically. The study was based on 135 Scots pine (Pinus sylvestris L.) logs that had been scanned with both a 3D scanner and an X-ray scanner with two X-ray sources. The percentage of boards with correct grade sawn from automatically graded logs varied from 57% when using only 3D scanning to 66% when using a combination of 3D scanning and X-ray scanning in two directions. The highest possible result, with ideal log grading, was 81%. The result also shows that the combination of a 3D scanner and one X-ray direction results in higher accuracy than a scanner based on two X-ray directions. 相似文献