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471.
IMAGING DIAGNOSIS—MUSCULAR HYPERTROPHY OF THE SMALL INTESTINE AND PSEUDODIVERTICULA IN A HORSE
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Cristobal Navas De Solís Elisabeth W. Biscoe Caleb M. Lund Karyn Labbe Juan Muñoz Kelly Farnsworth 《Veterinary radiology & ultrasound》2015,56(2):E13-E16
A 14‐year‐old Thoroughbred gelding was presented for chronic colic and weight loss. Transcutaneous and transrectal abdominal ultrasonography revealed distended, thickened small intestine with primary thickening of the muscularis and a focally more thickened loop with an echoic structure crossing the wall from the mucosa to the serosa. Visualization of diffuse thickening of the muscularis (muscular hypertrophy of the small intestine) and a focal lesion (pseudodiverticulum) helped clinicians make informed decisions. This case illustrates the importance of transabdominal and transrectal ultrasonography in horses with chronic colic and the relevance of considering the abnormalities in layering pattern of the intestinal wall. 相似文献
472.
Mukhtar Musa Festo Massawe Sean Mayes Ibraheem Alshareef 《Communications in Soil Science and Plant Analysis》2016,47(4):533-542
Bambara groundnut has great potential as an alternative crop for improving food security in its production regions and beyond. A field experiment was conducted at the Field Research Centre of the Crops for the Future to obtain information on the nitrogen (N) fixation and N balance of Bambara groundnut landraces on tropical acidic soils of Malaysia. Treatments consisted of three Bambara groundnut landraces (Ex-Sokoto, Kaaro, and NN-1) laid out in a randomized complete block design replicated three times. Results obtained revealed that Ex-Sokoto landrace was greater in yield and N fixation, whereas N balance (-haulm) was greater in NN-1 landrace. The results revealed grain yield of 703–2256 kg ha?1 and N fixation from 32–81 kg ha?1 and suggest that Bambara groundnut could be integrated into a cereal-based cropping system. Ex-Sokoto landrace appeared to be the most promising for yield and N fixation under Malaysian acidic soil conditions. 相似文献
473.
474.
Chan Sol Kang Il Jae Lee Moo Song Seo Sun Hong Kim Doo Hyun Baik 《Fibers and Polymers》2017,18(8):1580-1585
We purified as-received CNT fibers (CNTFs) with four different methods and systematically examined effects of various purifications on the morphology, structure, and electrical conductivity of the resultant CNTFs, respectively. The purified CNTFs were characterized by an optical microscope, transmission electron microscope (TEM) coupled with an energy dispersive X-ray spectrometer (EDS), Raman spectroscopy, and multiple source meters. Optical images showed that morphology of CNTFs did not largely change after purification. TEM images and EDS results showed that the Fe impurities, 21.9 wt%, in CNTFs were decreased to 0.17-1.20 wt% and were nearly eliminated by acid and alkali purifications, respectively. Raman results identified the ID/IG ratio of CNTFs was 0.71, while those of HCl treatment after steam with heat (HSCNTFs-HCl), NaOCl treatment after steam with heat (HSCNTFs-NaOCl), and NaOH treatment with heat without steam (NaOH-HCNTFs) were 0.45, 0.49, and 0.57, respectively, which means that purification methods of CNTFs performed in this study are thought to be satisfactory for manufacturing high-purity CNTFs. Electrical conductivity (1.4×104 S/m) of NaOH-HCNTFs (one-step procedure) was twice as high as that (7.3×103 S/m) of CNTFs, but lower than those (2.1-2.3×104 S/m) of HSCNTFs-HCl and HSCNTFs-NaOCl (two-step processes), which demonstrates that two-step processes rather than one-step procedure would have a positive effect on the electrical conductivity of the resultant CNTFs. 相似文献
475.
Sean D W Comber 《Pest management science》1999,55(7):696-702
Hydrolysis and photolysis experiments have been undertaken to investigate the abiotic persistence of atrazine and simazine in a variety of waters. Hydrolysis only occurs to a significant extent at pH values at the lower limit of those found in the natural aquatic environment (pH 4.0 or less). Photolysis was initiated by a wide range of wavelengths in waters at pH 4.0, but only by more energetic wavelengths of less than 300 nm at higher pH values (pH 6 to 8). Based on these data, the aquatic half-life of atrazine and simazine in well-lit acidic upland waters will be typically six days. In lowland rivers with higher pH (7 to 8.5), these triazines are likely to exhibit half-lives of months rather than days. In groundwaters, atrazine and simazine will have half-lives in the order of years, due to the exceedingly slow rate of hydrolysis. © 1999 Society of Chemical Industry 相似文献
476.
Two experiments over 21 days were conducted to assess the effect of different ionic profiles (mainly K+) of inland saline water (ISW) on the survival, growth, osmoregulation and moisture content of juvenile greenlip abalone Haliotis laevigata. In experiment I, the juveniles were cultured in five different water types: ocean water (OW) as a control, inland saline water (ISW or ISW K+0), ISW fortified with 33%, 66% and 100% K+ as in OW (ISW K+33, ISW K+66 and ISW K+100 respectively). In experiment II, five different culture media, 100% OW(control), 75% OW mixed with 25% ISW (ISW25), 50% OW mixed with 50% ISW (ISW50), 25% OW mixed with 75% ISW (ISW75) and 100% ISW (ISW or ISW100), were tested. Within 21 days, all of the abalone in ISW (ISW K+0 and ISW100; Na+/K+ ratio of 111 L?1) died compared with 100% survival in OW. One‐hundred per cent K+ fortification of ISW increased the specific growth rate (SGR) and serum osmolality of the surviving juveniles. The 96 h acute LC50 value was between ISW50 and ISW75. The increased proportion of ISW in OW resulted in significantly (P<0.05) lower survival, SGR and serum osmolality of juveniles. The moisture content of the juveniles was not influenced by any water type. The results suggested that abalone cannot survive in raw ISW, but survival can increase when it is fortified with K+ and ionic ratios of ISW are brought closer to OW by mixing it with OW. Furthermore, abalone survival is influenced by other ions in ISW besides K+. 相似文献
477.
478.
Chemical and biological characteristics of alkaline saline soils from the former Lake Texcoco as affected by artificial drainage 总被引:3,自引:0,他引:3
M. L. Luna-Guido R. I. Beltrán-Hernández N.A. Solís-Ceballos N. Hernández-Chávez F. Mercado-García J. A. Catt V. Olalde-Portugal L. Dendooven 《Biology and Fertility of Soils》2000,32(2):102-108
Soils from the former Lake Texcoco are alkaline saline and were artificially drained and irrigated with sewage effluents
since the late 1980s. Undrained soil and soil drained for 1, 5 and 8 years were sampled, characterized and incubated aerobically
for 90 days at 22±1 °C while production of CO2, available P and concentrations of NH4
+, NO2
– and NO3
– were monitored. Artificial drainage decreased pHH2O, water holding capacity, organic C, total N, and Na+, K+, Mg2+, B, Cl– and SO4
2– concentrations, increased inorganic C and Ca2+ concentrations more than 5-fold while total P was not affected. Microbial biomass C decreased with increased length of drainage
but bacteria, actinomycetes, denitrifiers and cellulose-utilizing bacteria tended to show opposite trends. CO2 production was less in soils drained ≥5 years compared to undrained soil but more than in soils drained for 1 year. Emission
of NH3 was negligible and concentrations of NH4
+ remained constant over time in each soil. Nitrification, as witnessed by increases in NO3
– concentrations, occurred in soil drained for 8 years. NO2
– concentrations decreased in soils drained ≤1 year in the first 7 days of the incubation and remained constant thereafter.
It was found that artificial drainage of soils from the former Lake Texcoco profoundly affected soil characteristics. Decreases
in pH and Na+, K+, Cl– and SO4
2– concentrations made conditions more favourable for plant growth, although low concentrations of inorganic N and available
P might be limiting factors.
Received: 1 December 1999 相似文献
479.
Evaluation of a Whole Blood Glutaraldehyde Coagulation Test for the Detection of Failure of Passive Transfer in Calves 总被引:1,自引:1,他引:0
Jeff W. Tyler Thomas E. Besser Leilani Wilson Dale D. Hancock Sean Sanders Douglas E. Rea 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(2):82-84
The accuracy of a commercially available whole blood glutaraldehyde clot test in the detection of failure of passive transfer (serum immunoglobulin [Ig]G1 < 1,000 mg/dL) in neonatal calves was evaluated. Serum samples were obtained from 242 calves ranging in age from 1 to 8 days, and comparisons were made with serum lgG1 concentrations determined by radial immunodiffusion. Both the sensitivity and specificity of the currently marketed whole blood glutaraldehyde clot test are inadequate for routine diagnostic use. Concerns regarding test sensitivity are the most problematic. Sensitivity varied from 0.41 to 0.00, depending on the choice of test endpoint. Specificity varied from 0.85 to 1.00, depending on the choice of test endpoint. Regression analysis demonstrated that the relationship between serum lgG1 concentration and the glutaraldehyde clot results, although significant (P< .10), was of negligible biological relevance ( r 2 = .034). J Vet Intern Med 1996; 10:82–84. Copyright © 1996 by the American College of Veterinary Internal Medicine . 相似文献
480.
The ultimate objective of a herd health and management program must be optimal farm net profit. Maximal profit can be expected by carrying out a program based on a whole farm approach. A simple and well-ordered registration system is one of the most important aspects for the success of a program. Experiences with the different registration systems of the program are discussed. In the future it is desirable to process the registered data by computer. The farmer should know the possibilities of the program in advance and must be motivated to carry out advice. When giving advice veterinarians have to take into account the specific circumstances on each farm and the objectives of the farmer. The veterinarian also has to be well-informed about the factors which influence the farm net profit and to this end cooperation with other experts is necessary. In this trial close cooperation between the veterinarian and agricultural adviser were seen as a very positive feature of the program. The program must be carried out at regular times in a fixed sequence, which covers complete herd health and farm management. The frequency of farm visits depends on the problems, farm size and the season. On average one visit per month will be sufficient for farms up to 100 dairy cows. Cooperation between farmer and veterinarian is one of the essential aspects. Frequent evaluation is very stimulating. The benefits of a herd health and management program were found to be substantial in this trial. Therefore the costs of the program can be considered by the farmer to be a sound investment. 相似文献