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101.
102.
ENDOSCOPIC ULTRASOUND INSTRUMENTATION, APPLICATIONS IN HUMANS, AND POTENTIAL VETERINARY APPLICATIONS
Lorrie Gaschen DVM PhD Patrick Kircher DVM Johann Lang DVM PD 《Veterinary radiology & ultrasound》2003,44(6):665-680
Endoluminal scanning under endoscopic guidance, or endoscopic ultrasonography (EUS), has become the most significant advance for imaging the gastrointestinal (GI) tract wall and contiguous organs in the past 20 years. It was originally designed to overcome the limitations in humans to imaging the abdominal organs transabdominally, such as large penetration depths and GI air. This imaging modality provides detailed images of pathological processes both within and outside of the GI wall since a high-frequency transducer can be brought into close proximity with the target regions. It has found most success in humans for the staging of lung, gastric, and esophageal cancer, the detection of both lymphatic and hepatic metastases, and diagnosis of pancreatitis and pancreatic cancer, as well as achieving an important role in interventional and therapeutic procedures. The EUS examination can be performed to examine both the thorax and abdomen in animals when both conventional transthoracic or transabdominal ultrasound are inadequate due to intervening air, bone, large penetration depths, or obesity. The echoendoscope is similar to a conventional endoscope but has an ultrasound transducer at its tip. Both radial and linear multifrequency scanners are available. Linear scanners allow fine-needle aspiration (FNA) of the bowel wall or extraluminal structures. Transducer coupling is either by direct mucosal contact or by inflation of a water-filled balloon surrounding the transducer. Current thoracic applications for EUS in veterinary medicine include examination of the mediastinum, bronchial lymph nodes, esophagus, and pulmonary lesions as well as FNA of pulmonary masses. Abdominal applications include examination of both pancreatic limbs and the liver, including portosystemic shunts, detection of lymphadenomegaly, and examination of the gastric wall, duodenum, and jejunum. Other potential applications in dogs and cats include tumor staging and intrapelvic ultrasound. 相似文献
103.
6-BA和GA3促进三色堇再生的研究 总被引:4,自引:0,他引:4
为了解决三色堇生产周期长,观赏期短等问题,对三色堇进行了再生利用的研究。结果表明,对过期三色堇进行刈割,留茬再生,喷施6-BA和GA3,并加强肥水管理,能生产出具有良好商业价值的再生三色堇。其中喷施6-BA的花朵数多、花大、叶宽、株型适中,具有良好的观赏价值,观赏期延长1倍。 相似文献
104.
Sabine Riesen DR MED VET Valerie Schmid DR MED VET Lorrie Gaschen DVM DR MED VET Andre Busato DR MED VET MSC Johann Lang PD DR MED VET 《Veterinary radiology & ultrasound》2002,43(6):554-560
The purpose of this study was to measure splanchnic blood flow during digestion in unsedated dogs by using duplex Doppler sonography. The study population consisted of 12 healthy dogs. Blood flow in the cranial mesenteric artery, the celiac artery, and the aorta was measured before a test meal and at 20, 60, and 90 minutes after eating. The following measurements were made or calculated: vessel diameter, peak systolic velocity, end diastolic velocity, mean velocity, resistive index, pulsatility index, and flow volume. There was a significant postprandial decrease in the resistive and pulsatility indices in both the cranial mesenteric (preprandial RI = 0.867, postprandial RI = 0.796, preprandial PI = 3.033, postprandial PI = 2.173) and the celiac (preprandial RI = 0.854, postprandial RI = 0.769, preprandial PI = 2.639, postprandial PI = 1.930) arteries. In both vessels the end diastolic velocity, the mean velocity, and the flow volume increased significantly postprandially. These changes occurred significantly earlier in the celiac artery than in the cranial mesenteric artery. The findings most likely correspond to postprandial splanchnic vasodilation. Doppler ultrasound provide a good methode of detecting changes in postprandial splanchnic blood flow in the dog. 相似文献
105.
对冬枣采后主要病害种类、症状及防治方法进行阐述,并介绍了生物防治技术在果蔬贮运病害防治中的应用,展望了该技术在冬枣采后病害防治中的应用前景. 相似文献
106.
107.
论述了"科技兴库"的意义和作用,并从五方面较详细地阐述了保证"科技兴库"的条件和措施,为培养和成为新时期合格的仓储工作者提供了借鉴条件。 相似文献
108.
Trace element release from forest floor can be monitored by ion exchange resin tubes 总被引:1,自引:0,他引:1
Risk assessment of heavy metal input into forest ecosystems requires information about metal fluxes from the forest floor (organic layer) into the mineral soil. Common methods for the monitoring of element fluxes are generally time‐consuming and expensive. Additionally, the reliability of the results is in part contested especially for trace elements, showing very low concentrations which are sometimes even below analytical detection limit. We used ion exchange resin tubes installed below the forest floor to determine heavy metal and As fluxes at 25 forest monitoring sites in Germany. Chloride tracer experiments and the comparison of our data with throughfall and lysimeter data, determined within the Level II monitoring network, proved the accuracy of our method. Mean trace element fluxes based on the resin method were 50 g As ha–1 yr–1, 2 g Cd ha–1 yr–1, 168 g Cu ha–1 yr–1, 176 g Ni ha–1 yr–1, and 186 g Pb ha–1 yr–1.The results show that the organic layer may change into a source of heavy metals after emission has decreased. 相似文献
109.
110.
近些年来,水稻免耕抛秧栽培在中国广西等部分地区发展迅速。为了探讨免耕抛栽水稻产量形成特点,以金优253(OryzasativaL.)为试验材料,以常耕抛栽水稻为对照,从叶面积大小、剑叶光合速率与衰老、库的大小及源库比率等方面研究了免耕抛栽水稻的源库特性。结果表明,免耕抛栽水稻早、晚季产量分别为5.97t/hm2和7.53t/hm2,常耕抛栽水稻分别为6.19t/hm2和7.63t/hm2,其产量差异在早季和晚季均不显著。与常耕抛栽水稻相比,免耕抛栽水稻的每穗总粒数和单位面积上的总粒数较多,各生育期的叶面积指数较大,灌浆期剑叶光合速率、蒸腾速率、气孔导度、叶绿素含量较高,而过氧化物酶和过氧化氢酶活性及丙二醛的含量较低,在生理上存在一定的优势。但是,免耕抛栽水稻的源库协调能力较差,粒叶比和结实率下降,致使免耕抛栽水稻在产量上表现出一定的劣势。免耕抛栽水稻粒叶比和结实率的下降是由于其生产的干物质更多地分配在叶片中、贮藏在茎鞘中的干物质在抽穗后向穗部运转的能力较差造成的。 相似文献