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21.
Foreign bodies in the soft tissues are frequent problems in both veterinary and human medical practice. Radiography has been the principle tool for diagnosis, but is unable to define many foreign bodies. This study was undertaken to compare the sonographic and radiographic visualization for a variety of foreign bodies. Fresh turkey muscle (pectoral and thigh) with skin was used as the soft tissue model. Assorted foreign bodies were introduced 1 cm into the muscle. Materials examined were small wood fragments, steel wire, glass, nails, graphite, rock, BB pellets, and polystyrene plastic. Following introduction of the foreign bodies radiographs were obtained and the specimens were studied sonographically at 5.0 mHz and 7.5 mHz. All foreign bodies were visible with sonography. A bright echo with either acoustic shadowing or reverberations was present for all specimens. Radiographically metallic foreign bodies were visible but wood, some graphite, and plastic were not seen. We conclude that radiography should remain the primary imaging modality for foreign body detection because of its general availability and low cost. If radiography is negative ultrasound can detect and guide the removal of radiolucent foreign bodies.  相似文献   
22.
The ratio between maximal small intestinal (SI) diameter and the height of the body of the fifth lumbar vertebra (L5) in radiographs has been reported as a diagnostic test in dogs with suspected intestinal obstruction. In order to assess the effect of the SI/L5 ratio on the accuracy of radiographic diagnosis of intestinal obstruction, lateral abdominal radiographs of 37 dogs with small intestinal obstruction and 48 nonobstructed dogs were mixed and examined independently by six observers who were unaware of the final diagnosis and who represented a range of experience. Observers first examined radiographs subjectively and stated the likelihood of obstruction (definitely not, probably not, equivocal, probably, definitely). Observers subsequently reexamined the radiographs, determined the SI/L5 ratio, and again stated the likelihood of obstruction. The most frequent cause of obstruction was foreign body (29/37, 78%). Dogs with SI obstruction had a significantly larger median SI/L5 ratio than nonobstructed dogs (P = 0.0002). Using an SI/L5 ratio of 1.7 for diagnosis of intestinal obstruction, sensitivity and specificity were 66%. Use of the SI/L5 ratio was not associated with increased accuracy of diagnosis for any observer, regardless of experience, hence this test may have no diagnostic impact.  相似文献   
23.
To determine the distribution of stem decay in the beech stands of Azerbaijan, we sought to identify the species, number, and height of attachment of fruiting bodies;the extent of decay in tree trunks growing under different conditions;and its influence on the trees’ commercial wood. The research was conducted on three farms representing the most common forest types of the Greater Caucasus within Azerbaijan. Examination of the presence of fruiting bodies in the tree trunk revealed that stem decay is the most common infection in beech (Fagus orientalis) stands, especially in fresh, moist areas, with less infection under dry growing conditions. In this work, the length, diameter, and volume of decay were studied by infecting the trunks of 93 model trees affected with mushrooms in 1–4 m cuttings. Our results showed that as the age of the stand increased, extent, diameter, and volume of decay increased significantly: the extent of decay from 1.47 to 6.43 m;the diameter of the decay from 8.15 to 32.7 cm;and the volume of decay from 2.5 to 13.2%. The relationship between age and the specified indicators is presented graphically. Using data obtained from the same sample of trees, we determined the expected and actual yield of commercial wood by age class. We determined that stem decay in beech stands leads to a decrease in the yield of commercial wood on average from 25.1% in the middle-aged to 14.8% in overmature plantations, respectively, with an estimated yield of 40.8–62.7%. Here we present mathematical models of the output of commercial wood from the infected part of the stands by age classes with the use of average data on the extent of decay in model trees.  相似文献   
24.
Abstract: Two young adult dogs with gastrointestinal signs were each found to have an intra‐abdominal mass based on physical examination and diagnostic imaging. On exploratory laparotomy, small intestinal masses and mesenteric lymphadenopathy were found in both dogs; a liver mass was also found in dog 1. Cytologic and histologic examination of intestinal and liver masses and mesenteric lymph nodes revealed 2 distinct lymphoid cell populations: lymphoblasts and atypical Mott cells. With Romanowsky stains, the atypical Mott cells contained many discrete, clear to pale blue cytoplasmic inclusions consistent with Russell bodies that were positive by immunohistochemistry for IgM and CD79a in both dogs and for IgG in dog 2. The Mott cells and occasional lymphoblasts stained strongly positive with periodic acid‐Schiff. Using flow cytometric immunophenotyping in dog 1, 60% of peripheral blood mononuclear cells and 85% of cells in an affected lymph node were positive for CD21, CD79a, IgM, and MCH II, indicative of B‐cells. With electron microscopy, disorganized and dilated endoplasmic reticulum was seen in Mott cells in tumors from both dogs. Antigen receptor gene rearrangement analysis of lymph node and intestinal masses indicated a clonal B‐cell population. Based on cell morphology, tissue involvement, and evidence for clonal B‐cell proliferation, we diagnosed neoplasms involving Mott cells. To the authors' knowledge, this is the second report of Mott cell tumors or, more appropriately, B‐cell lymphoma with Mott cell differentiation, in dogs. More complete characterization of this neoplasm requires further investigation of additional cases. This lymphoproliferative disease should be considered as a differential diagnosis for canine gastrointestinal tumors.  相似文献   
25.
不同光谱能量分布对文心兰组织培养的影响   总被引:1,自引:0,他引:1  
采用发光二极管(light emitting diode,LED)调制获取不同光谱能量分布的光源,以荧光灯为对照,研究其对文心兰原球茎诱导、增殖及生根组培苗生长的影响。结果表明:红光有利于原球茎的诱导,并促使原球茎产生最高的增殖系数和碳水化合物含量以及最低的分化出芽率;蓝光使原球茎产生最高的蛋白质含量、酶系活力和分化出芽率;单一红光促进文心兰生根苗茎的伸长,但不利于叶片色素的形成;单一蓝光抑制生根苗茎的伸长,促进叶片蛋白质和色素的合成;红蓝光谱分布处理的生根苗的生长量、干重、能效和酶系活力指标均高于荧光灯对照,色素含量与荧光灯对照无显著差异;红光LED促进文心兰原球茎的诱导,蓝光LED促进分化,红蓝光谱构成的LED光源更有利于生根组培苗的正常生长,是替代荧光灯的理想光源。   相似文献   
26.
The processing properties of wheat flour are largely determined by the structures and interactions of the grain storage protein, the so called “gluten proteins”. The synthesis, folding and deposition of the gluten proteins take place within the endomembrane system of the plant cell. Several studies have suggested that two trafficking pathways occur in wheat, with the proteins either being transported via the Golgi apparatus into the vacuole or assembling within the ER to form protein bodies that are subsequently internalized into vacuoles by a process analogous to autophagy. The precise routes of trafficking and deposition of individual gluten proteins remain unclear and so are the molecular and cellular mechanisms regulating their sorting in the two pathways.  相似文献   
27.
乔金杰  赵秋莲  赵海燕 《安徽农业科学》2011,39(21):13218-13220
针对多目标农业技术创新主体投资收益低于预期收益问题,提出了多目标二级灰色优化方法。在满足较低水平最优目标和灰色区间预测值内,以主体投资与较高水平目标的灰色关联度为权重,从而把多目标灰色优化转化为单目标线性规划。并给出了主体投资的非劣策略。最后对1990~2006年时间序列进行实证分析和改进区间预测,得到更加有价值的区间,并发现农户投资行为对创新效益的贡献率最大,同时得到了满足农户最优目标条件下的非劣行为策略,验证了该方法的有效性。  相似文献   
28.
To improve sorghum grain protein nutritional quality, improved sorghum lines were transformed to suppress the synthesis of different kafirin sub-classes, or backcrossed into transgenic lines with improved protein quality. Co-suppression of the alpha-, gamma- and delta-kafirin sub-classes and removal of the tannin trait resulted in transgenic sorghum lines with high cooked protein digestibility (±80%), improved Amino Acid Score (0.8) and Protein Digestibility Corrected Amino Acid Score (0.7) compared to the non-transgenic null controls (±50%, 0.4 and 0.2, respectively). These high protein quality lines had a floury endosperm. They also had modified protein body structure, where the protein bodies were irregular shaped with few to numerous invaginations and were less densely packed, with a dense protein matrix visible around the protein bodies. When fewer sub-classes were suppressed, i.e. gamma 1 and delta 2, the endosperm was corneous with normal protein body structure but the improvement in cooked protein digestibility appeared to be less. Apparently, co-suppression of several kafirin sub-classes is required to obtain high protein nutritional quality sorghum lines, but this seems to result in floury-type grain endosperm texture.  相似文献   
29.
水稻黑条矮缩病毒(Rice black streaked dwarf virus,RBSDV)是斐济病毒属的成员,由昆虫介体灰飞虱传播,能够在植物宿主和昆虫介体中复制。同其他斐济病毒成员一样,RBSDV的复制与装配是在细胞质病毒包涵体结构即毒质结构里进行的。RBSDV有10条基因组dsRNAs(S1—S10),其第9条片段(S9)的第一个阅读框(ORF)编码的蛋白P9 1是形成毒质结构的框架蛋白。将P9 1与绿色荧光蛋白(GFP)融合后,在本氏烟草的表皮细胞中单独表达,通过激光共聚焦扫描显微镜观察发现P9 1可以形成包涵体结构;利用双分子荧光互补(BiFC)实验证明了P9 1具有自我互作的能力,并形成包涵体结构。  相似文献   
30.
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