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排序方式: 共有502条查询结果,搜索用时 15 毫秒
191.
LEONIE W. L. VAN BRUGGEN HERMAN A. W. HAZEWINKEL CLAUDIA F. WOLSCHRIJN GEORGE VOORHOUT YVONNE W. E. A. POLLAK PAUL Y. BARTHEZ 《Veterinary radiology & ultrasound》2010,51(3):344-348
Few reports have been published regarding the use of scintigraphy in the diagnosis of elbow joint lameness in dogs. Some authors have speculated about the potential use of bone scintigraphy and its suspected high sensitivity for the early diagnosis of abnormalities of the medial coronoid process (MCP) in dogs. Scintigraphy is used routinely in our institution in dogs presented for thoracic limb lameness and/or suspected of abnormalities of the MCP when radiographic findings were equivocal. Radiographic, scintigraphic, and surgical findings of the elbow joints of 17 dogs with elbow joint lameness were compared with radiographic, scintigraphic, and necropsy findings of the elbow joints of 12 clinically healthy Labrador Retrievers. Quantitative evaluation of scintigraphic images was performed to determine relative radiopharmaceutical uptake in the region of the MCP. Maximum relative uptake of the coronoid process in the normal dogs was taken as a threshold value to classify elbows as positive or negative for an abnormal MCP after all 24 elbows of the 12 healthy dogs were confirmed as being normal at necropsy. All 17 elbows from lame dogs were positive on scintigraphy and confirmed as having chondromalacia, a fissure, or fragmentation of the MCP. Based on our results, bone scintigraphy may be a valuable diagnostic tool for the diagnosis of abnormalities of the MCP in dogs, and particularly in older dogs where clinical and radiographic changes may be ambiguous. 相似文献
192.
MIGUEL CAMPOS JIMMY H. SAUNDERS LUC DUCHATEAU GEERT PAES ELKE VAN DER VEKENS SYLVIE DAMINET 《Veterinary radiology & ultrasound》2010,51(3):331-334
In humans, administration of recombinant human thyroid stimulating hormone (rhTSH) allows radioactive iodine dose reduction and higher efficacy in the treatment of multinodular goiter and thyroid cancer. A similar effect might be expected in dogs with thyroid carcinoma. However, if rhTSH leads to an increase in thyroid volume, it must be used carefully in dogs with large thyroid tumors to avoid compression of key anatomical structures. The aim of this study was to determine the short‐term effect of rhTSH on thyroid volume and echogenicity, measured by ultrasonography, in healthy Beagles. Seven beagles were divided randomly in two groups in a prospective placebo‐controlled blinded cross‐over study. On day 1, one group received 100 μg of rhTSH intravenously and the other group received placebo. After a wash‐out period of 3 weeks, the groups were crossed over. Evaluation of thyroid echogenicity, homogeneity, shape, capsule delineation, and measurement of thyroid length, width, and height were performed by the same observer at baseline, and at 6, 24, and 48 h after injection of rhTSH and placebo. There was no significant difference between the effect of rhTSH and placebo on thyroid volume (P=0.397), echogenicity, homogeneity, or capsule delineation. Time had a significant effect on thyroid volume (P=0.027). No adverse effects after rhTSH administration were noticed. The effect of rhTSH on thyroid volume in dogs with thyroid carcinoma needs to be assessed. 相似文献
193.
INGE DURIE GUNTHER VAN LOON SIMON VERMEIRE DOMINIQUE DE CLERCQ KATLEEN VANSCHANDEVIJL PIET DEPREZ 《Veterinary radiology & ultrasound》2010,51(5):540-544
Little information is available on medical imaging of the adrenal glands in horses. We investigated the feasibility of transrectal ultrasonography to characterize the normal equine adrenal gland. Transrectal ultrasonography was performed in 25 healthy horses using a 7.5 MHz linear array probe at a displayed depth of 8 cm. Transrectal ultrasonography of the right adrenal gland was not feasible. For the left adrenal gland, the left kidney, the abdominal aorta, the left renal artery, the left renal vein, and the cranial mesenteric artery were used as landmarks. The size of the left adrenal gland was variable, but it generally appeared as a long, flat structure with a hyperechoic medulla surrounded by a hypoechoic cortex. The most cranial part of the gland could not be delineated appropriately in 11 horses (44%). The mean (±SD) thickness of the gland and medulla was 0.66±0.15 cm (n=25) and 0.28±0.09 cm (n=25) near the caudal pole, 0.87±0.25 cm (n=14) and 0.40±0.18 cm (n=12) near the cranial pole, and 0.89±0.18 cm (n=25) and 0.36±0.13 cm (n=25) in the middle of the gland, respectively. The mean (±SD) length of the entire adrenal gland and of the medulla was 6.22±0.77 cm (n=14) and 5.45±0.71 cm (n=6), respectively. Transrectal ultrasonography allowed adequate visualization of the left adrenal gland in horses. 相似文献
194.
Analytical pyrolysis of a soil profile under Scots pine 总被引:1,自引:0,他引:1
The chemical properties of pine needle litter cause slow decomposition, which results in an accumulation of highly lignocellulosic material on the forest floor. Decomposition of organic matter is important for the nutrient turnover in pine forests on nutrient-poor soils. We studied the biodegradation of needles in an organic layer focusing on the various stages of lignin degradation by fungi. Samples were obtained from pine needle litter and a stratified organic layer over nutrient-poor sand under a 60-year-old Scots pine (Pinus sylvestris forest stand. Pyrolysis mass spectrometry (PyMS) and pyrolysis gas chromatography mass spectrometry (PyGCMS) were used to characterize the chemical composition of the needles and the soil. The pyrolysis data show that diterpenoid acids are a main component in fresh needles, but rapidly decrease in the organic layer of the soil, as a result of decomposition. The chemical composition of the soil profile is dominated by guaiacyl lignin and polysaccharides from needle litter. The hexose/pentose ratio increases with depth in the soil profile. The partial preservation of hexose polymers is the result of the preferential decomposition of pentose polymers by white-rot fungi, and points to the input of microbially synthesized polysaccharides. Indications for the degradation of guaiacyl lignin are also found in the soil profile. Oxidative reactions by soil fungi result in a shortening of the side chain of the guaiacyl lignin derivatives and an increase of carbonyl and carboxyl groups. These degradational patterns of lignin in the soil profile under Scots pine are similar to those observed in lignin model compounds and wood lignin degraded by fungi under controlled laboratory conditions. 相似文献
195.
应用酶联免疫吸附试验(Enzyme linked immunosorbent assay,ELISA)对在2011年间采自西藏(988份)、青海(475份)和四川(377份)共1840份牦牛血清样品进行牛传染性鼻气管炎病毒抗体检测。结果检出阳性血清样品西藏381份,阳性率38.6%;青海212份,阳性率为44.6%;四川105份,阳性率为27.9%。结果表明,中国西部高原西藏、青海以及四川牦牛群中均存在牛传染性鼻气管炎病毒的感染。本研究调查了牛传染性鼻气管炎在中国西部高原牦牛群中的流行情况,为制定该病的防治措施提供理论依据。 相似文献
196.
Stratification of a region based on soil map delineations followed by within-stratum interpolation is sometimes used to combine soil maps and spatial interpolation. However, not all delineations are equally suitable to subdivide an area into precisely located mutually exclusive strata. This paper proposes a flow-path to characterize the nature of soil map delineations and a methodology to integrate the properties of map delineations into ordinary kriging.Four types of delineations were distinguished based on three criteria: the nature of transition (discontinuous or gradual), the mapping accuracy, and the structure of the within-unit spatial variation. For each type of delineation the ordinary kriging algorithm was modified to integrate its properties in the interpolation.As a test case, the sand content of the topsoil in the province of West-Flanders (Belgium) was mapped, using independent test data for validation. Inside the mapping units and at delineations identified as gradual transitions, our procedure, termed ordinary kriging integrating properties of map delineations (OKPD) , performed similarly to stratified ordinary kriging (SOK). However, close to the delineations identified as inaccurately mapped discontinuities the mean square prediction error of OKPD was 0.64 times that of SOK. Moreover, near these delineations, the prediction variance was largely underestimated by SOK (relative variance = 5.1), whereas OKPD produced a more realistic value (relative variance = 1.5). 相似文献
197.
Charge characteristics in relation to free iron and organic matter of soils from Bambouto Mountains, Western Cameroon 总被引:1,自引:0,他引:1
We have examined the charge characteristics, with special emphasis on the role of free Fe and organic matter, of humid tropical soils from Bambouto Mountains, Western Cameroon. The soils, which are formed from tuff, basalt and trachyte, are dominated by kaolinite and sesquioxides. The amounts of Fe oxides in them increase somewhat with depth. Open 2:1 phyllosilicates are present in trace amounts. The point of zero charge of the variable charge components, pH0 , is around 4 in the topsoil (0–20 cm) and around 6 at 100–150 cm depth. In the subsoils, pH0 exceeds soil pH presumably because of large quantities of Fe oxides. Deferration increases both soil pH and pH0 , but diminishes the anion exchange capacity. Oxides and oxyhydrates of Fe have positive surface charge, so their removal from the soils would result in overall loss of positive charge. Increases in soil pH would bring about an increase in the cation exchange capacity of the soils. Hence, management practices that reduce soil acidity should reduce loss of essential basic cations via leaching. 相似文献
198.
氮肥对新疆棉花产量形成期叶片光合特性的调节效应 总被引:25,自引:3,他引:25
在新疆生态条件下,采用裂区设计研究了氮肥用量对棉花产量形成期叶片光合特性的调节效应。结果表明,适量追施氮肥在一定程度上可以改善叶片光合性能,提高植株生育后期叶片叶绿素含量和硝酸还原酶(NR)活性;维持叶片较高的PSⅡ潜在活性(Fv/Fo)和PSⅡ光化学最大效率(Fv/Fm);提高中下部叶片的光合速率,延缓了叶片衰老,保证了棉花生育后期光合产物的形成,从而使棉花达到高产。这种调节效应因品种和生育时期的不同而异。新陆早6号在盛铃前期叶片叶绿素含量、NR活性、光合速率及Fv/Fo和Fv/Fm随氮肥用量增加而增加,盛铃后期至吐絮期叶绿素含量、Fv/Fo和Fv/Fm、叶片光合速率等指标均以中氮处理(300.kg/hm2)最高,高氮处理易造成植株盛花期生长过旺,群体荫蔽,影响了叶片光合作用;新陆早7号中氮处理与高氮处理之间差异不明显。因此,生产上应根据不同品种和生育时期进行合理施肥,避免因施肥不当造成产量下降和浪费肥料。 相似文献
199.
今年是个暖冬,而且春节来得也晚,加之今年又是北京奥运及各项配套工程、城市建设项目都到了决战决胜的最后一个年头。工程紧、任务重,为确保按计划完成多种施工目标,同时又要保证质量及奥运绿色环保的要求,整个春节长假期间,京城地区几乎每个重点基建工程工地都有大批的工人留守工地,坚持施工生产。今年春节这一情景与往年春节各个施工工地上冷冷清清的景况形成了最大的反差。因而由此带动了重要生产资料之一的建筑木材的极大需求。反映在以针叶原木、各类建筑板材为主的木制建材市场上,可以说就如同春节的喜庆气氛相和相谐。 相似文献
200.
Antonius G. T. SCHUT Emily C. COOLEDGE Marc MORAINE Gerrie W. J. VAN DE VEN Davey L. JONES David R. CHADWICK 《农业科学与工程前沿(英文版)》2021,8(1):111-129