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1.
Leib MS Dinnel H Ward DL Reimer ME Towell TL Monroe WE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(6):547-552
Endoscopic balloon dilation of benign esophageal strictures was performed in 18 dogs and 10 cats with a median age of 4 years. Stricture formation was associated with a recent anesthetic episode in 18 patients. Regurgitation was the most common clinical sign and was present a median of 4 weeks before dilation. Most animals had a single stricture; median diameter was 5 mm, and median length was 1 cm. Esophagitis and mucosal fibrosis were detected in 9 patients each. Dilation was performed with progressively increasing diameter balloons, from 6 to 20 mm. After dilation, mucosal hemorrhage was mild to moderate in most patients. Esophageal perforation was the only serious complication and occurred in 1 patient. Postdilation therapy consisted of administration of cimetidine, metoclopramide, sucralfate, and prednisone in most animals. The median number of dilation procedures performed in each animal was 2, with a range of 1-5. The median interval between dilations was 13 days. Stricture diameter markedly increased with subsequent dilations. Median duration of follow-up was 131 weeks. A successful outcome occurred in 88% of patients, with most animals able to eat canned, mashed, or dry food without regurgitation. Mucosal fibrosis was associated with a better clinical response score, while increasing age was weakly associated with fewer dilations. The dilation protocol used in this group of animals was safe and efficacious. 相似文献
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WEI Shuhua LIANG Jun YE Jianren ZHANG Xingyao** . School of Resources Environment of Nanjing Forestry University Nanjing P.R. China . Institute of Forest Ecology Environmental Protection Chinese Academy of Forestry Beijing P.R. China 《中国林业科技(英文版)》2007,6(1):62-68
Toxin, one of the most important factors of plant fungal disease, has attracted much attention of many academicians who have been studying pathogen mycotoxin in deep research. The paper summarized chemical structures of some host-selective plant pathogen mycotoxins discovered in recent years and the correlation between biological activity and chemical structure of toxin. 相似文献
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Laboratory experiments wer conducted to determine the effects of Kepone on the larval development of the mud-crab,Rhithropanopeus harrisii, and the commercial blue crab,Callinectes sapidus, from the time of hatching until the 1st crab stage was reached. Differential survival ofR. harrisii from hatching to 1st crab stage occurred in a range of 35 to 125 ppb Kepone, whereas differential survival ofC. sapidus over the same period of development occurred in a range of 0.1 to 1.0 ppb. Statistical analysis indicated that, for every 10 ppb Kepone added, duration from hatching to 1st crab stage ofR. harrisii was increased by 0.391±0.043 days; whereas for each increase of 0.1 ppb, the duration from hatching to 1st crab stage ofC. sapidus is prolonged by 0.38±0.10 days. The 1st and 2nd zoeal stages ofR. harrisii were the most sensitive developmental stages to Kepone, but the 1st zoeal stage ofC. sapidus was not sensitive, statistically, to any concentration of Kepone tested. In zoeal stages II, III and IV, there were significant increases in mortality ofC. sapidus over the previous stage in all media tested. 相似文献
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C. G. Bookhout R. J. Monroe R. B. Forward Jr. J. D. Costlow Jr. 《Water, air, and soil pollution》1984,21(1-4):199-216
Survival of Rhithropanopeus harrisii larvae from hatching to first crab stage occurred in Na2CrO4 concentrations from 1.1 to 29.1 ppm. Estimated LC50 for complete zoeal development was 17.8 ppm Na2CrO4 and it was 13.7 ppm for development to first crab stage. A concentration of 1.1 ppm Na2CrO4 was nontoxic, while Na2CrO4 concentrations of 7.2 and 14.5 ppm were sublethal and concentrations of 29.1 to 58.1 ppm were acutely toxic. Low concentrations of Na2Cr04 caused an increase in swimming speed and high concentrations caused a decline. Survival of Callinectes sapidus larvae occurred in Na2CrO4 concentrations from 1.1 to 4.7 ppm. The LC50 for complete zoeal development was estimated to be 2.9 ppm Na2CrO4 and the LC50 for development to first crab stage was estimated to be 1.0 ppm Na2CrO4 The total Cr in sodium chromate is 32% by weight (Tacey,1981), hence, the total Cr concentrations tested were 32% of the Cr salts given above. Statistical analyses of the data on survival, duration and mortality of larvae are presented. 相似文献
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Lead-salt tunable diode lasers (TDLs) are the only devices currently available that can generate tunable monochromatic radiation at arbitrary wavelengths between 3 and 30 micrometers and are particularly useful for high-resolution spectroscopy over a wide range of spectral regimes. Detailed observations of TDLs show that the observed instrumental linewidth is actually a temporal average of many narrow (less than 0.5 megahertz) emission "modes." The time scale characteristic of these "modes," which appear to be of relatively constant intensity, is of the order of a microsecond. The laser's behavior is highly suggestive of a chaotic process, that is, seemingly random excursions of a dynamic variable (frequency) within a bounded range. This report shows experimentally that TDL emissions are indeed chaotic. Furthermore, in a simple and robust fashion, this chaotic behavior has been successfully controlled with the use of recent techniques that take advantage of chaos to produce a narrow band laser output. 相似文献
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用离子交换平衡法研究了不同pH下胡敏酸与锌、镉单独及复合存在下形成络合物的稳定性及配位数.结果表明:在Zn2+,Cd2+单独存在时,络合反应的稳定常数及配位数随着pH值的增大而增大;相同pH条件下,Zn2+和胡敏酸络合物的稳定常数及配位数大于Cd2+.在Zn2+,Cd2+复合存在时,pH的变化与胡敏酸络合金属离子的稳定常数及配位数没有明显依存关系;与单独存在时相比,在pH 3.5和pH7.0时,Zn2+,Cd2+和胡敏酸络合物的稳定常数和配位数都减小;而在pH 5.0时,Cd2+和胡敏酸络合物的稳定常数和配位数都增大,Zn2+和胡敏酸络合物的稳定常数和配位数都减小. 相似文献
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A 24-yr-old, male western lowland gorilla (Gorilla gorilla gorilla) was diagnosed with congestive heart failure using transesophageal and transthoracic echocardiology. New York Heart Association (NYHA) Class III was assigned to the severity of the condition. Over 16 mo, this progressed to NYHA Class IV despite increasing medical therapy. Repeated evaluations suggested that implantation of a cardiac resynchronization therapy device with a defibrillator (CRT-D) could benefit this animal based on clinical signs and underlying evidence of dyssynchrony and suspected fibrotic myocardial disease. Surgical implantation of leads into the right atrium, right ventricle, and left ventricle was accomplished. The CRT-D device was placed under the thoracic pectoral muscles during an initial surgical procedure. Improvement in the gorilla's clinical condition after implantation of the CRT-D device was immediate and dramatic. Subsequent scanning of the device was accomplished through operant conditioning. The data from these device interrogations included stored and real-time cardiac data, which were used to minimize recognized environmental stressors and change device settings. Over 4 yr, case management was critical to successful device use in treatment of the clinical disease. This involved medications, training for device interrogation, exercise to increase activity and improve body condition, and phlebotomy attempts. Dietary management was necessary to manipulate caloric and sodium intake and encourage medication compliance. Cardiac resynchronization therapy device implantation, although requiring specialized equipment and surgical skill, appears to be a viable option for treatment of fibrosing cardiomyopathy with systolic dysfunction in gorillas refractory to medical management. In addition to treatment, this device provides cardiovascular data at rest that could allow for early diagnosis and treatment of gorillas with this and other cardiac conditions in the future. This describes the comprehensive medical, husbandry, and training techniques necessary to successfully manage this intense clinical case in conjunction with intracardiac device therapy. 相似文献
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