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41.
Pyrolysis-gas chromatography-mass spectrometry was used to characterize fungal melanins and model phenolic polymers. Samples were pyrolysed at 700°C for 10 s and the low boiling-point compounds were separated on a Chromosorb 102 column. Low boiling-point compounds identified with a mass spectrometer coupled to the gas Chromatograph were very similar for peptone, a model autoxidative phenolic polymer incorporating peptone, and some fungal melanins. The major low boiling-point components from fungal melanins were related to proteins and to polysaccharides. A nitrogen-free phenolic polymer yielded very small amounts of low boiling-point pyrolysis fragments. The compounds identified appeared to be derived largely from the peptide, carbohydrate, and possibly small amounts of other aliphatic materials in the polymer structures. 相似文献
42.
The validity of the new Dutch feed evaluation system for dairy cattle was tested by using the results of energy balance experiments in Wageningen and of Scandinavian feeding trials performed by Frederiksen and Dijkstra. From the digestibility in vivo by wethers or in vitro, the metabolizable energy in the ration was predicted as well as the net energy to be produced. In the latter, the net energy for maintenance was assumed to be metabolic body weight. Prediction of energy in milk and energy balance agreed well with the results of energy balance trials with dairy cows fed on winter rations. For fresh grass a discrepancy was found which is not yet explainable, but further research on this subject is in progress. In the feeding trials, the measured average weight change agreed rather well with the predicted energy balance. Finally, the reliability of these methods for testing this new feed evaluation system is discussed. 相似文献
43.
Y. Xue H. M. van Es R. R. Schindelbeck B. N. Moebius‐Clune J. J. Melkonian C. Graham P. Yang 《Soil Use and Management》2013,29(2):240-249
Changes in the profile distribution of soil C stocks for conventional versus no‐tillage can affect N2O losses. Uncertainty remains whether deep N placement into a wetter layer in humid areas would affect N2O losses. This study evaluated the effects of soil carbon profile distribution (inverted, normal), depth of nitrogen placement (5 cm, 15 cm), temperature (10, 20 and 30 °C) and soil texture (clay loam, loamy sand) on N2O emissions from soil cores in a 216‐h incubation after simulated rainfall. N2O losses were larger from the clay loam than from the loamy sand, and cumulative N2O emissions from the inverted profile, with greater C levels at depth, were more than those from the profile with more C near the upper surface. Cumulative N2O losses from the inverted clay loam profile with deep N placement (1.16 mg N per kg dry soil; 0.71% of applied N) on average were almost double those in the loamy sand (0.62 mg N per kg dry soil; 0.42%). The smallest N2O losses were measured from the profiles with more C close to the upper surface with a shallow placement of N for the clay loam (0.19 mg N per kg dry soil; 0.12%) and loamy sand (0.33 mg N per kg dry soil; 0.23%). An exponential relationship between N2O fluxes and temperature was measured. We conclude that large N2O losses may occur under the combination of greater soil C content at deeper layers (ploughed soils) and moist profiles after N application (humid regions). Deep N placement appears to aggravate rather than ameliorate these concerns. 相似文献
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46.
DANIEL J. BROCKMAN BVSc Diplomate ACVS & ECVS KATE E. BORER BVSc Cert VA Diplomate ECVA STEPHEN J. BAINES MA Vet MB PhD Diplomate ECVS DEZ HUGHES BVSc Diplomate ACVECC VIRGINIA LUIS FUENTES MA Vet MB PhD Diplomate ACVIM 《Veterinary surgery : VS》2009,38(5):631-635
Objective— To report successful surgical treatment of double chambered right ventricle (DCRV) in a cat.
Study Design— Clinical report.
Animals— Cat with DCRV.
Methods— DCRV was diagnosed in a 5-month-old male Maine Coon cat using echocardiography and angiocardiography. At 2 years, despite medical therapy, chylothorax developed. A section of the right ventricular free wall that spanned the fibromuscular obstruction was excised under total venous inflow occlusion (TVIO) using the incised pericardial patch technique.
Results— Short-term recovery was complicated by return of chylothorax but this resolved after thoracocentesis and diuretic therapy. Three years after surgery, the cat is free of clinical signs and no longer on any medical therapy.
Conclusions— Partial right ventriculectomy can be performed under TVIO through an incised pericardial patch.
Clinical Relevance— DCRV in cat can be successfully treated by partial right ventriculectomy performed under TVIO through an incised pericardial patch. 相似文献
Study Design— Clinical report.
Animals— Cat with DCRV.
Methods— DCRV was diagnosed in a 5-month-old male Maine Coon cat using echocardiography and angiocardiography. At 2 years, despite medical therapy, chylothorax developed. A section of the right ventricular free wall that spanned the fibromuscular obstruction was excised under total venous inflow occlusion (TVIO) using the incised pericardial patch technique.
Results— Short-term recovery was complicated by return of chylothorax but this resolved after thoracocentesis and diuretic therapy. Three years after surgery, the cat is free of clinical signs and no longer on any medical therapy.
Conclusions— Partial right ventriculectomy can be performed under TVIO through an incised pericardial patch.
Clinical Relevance— DCRV in cat can be successfully treated by partial right ventriculectomy performed under TVIO through an incised pericardial patch. 相似文献
47.
JEAN-MICHEL E. VANDEWEERD DVM DES Cert ES ROLAND PERRIN DVM Diplomate ECVS THOMAS LAUNOIS DVM Diplomate ECVS LAURENT BROGNIEZ DVM SIMON GEHIN DVM PETER D. CLEGG MA VetMB Cert EO Diplomate ECVS MRCVS FRANCIS G. DESBROSSE DVM Diplomate ECVS 《Veterinary surgery : VS》2009,38(3):373-379
Objectives— To compare the precision of radiography and computed tomography (CT) preoperatively in the standing position for identification of guidelines for screw insertion in the distal phalanx, and to identify whether standing CT might improve operative time compared with preoperative radiographic planning.
Study Design— Experimental ex vivo study.
Animals— Cadaveric equine thoracic limb pairs (n=10).
Methods— Insertion of a 4.5 mm cortex screw in lag fashion into an intact distal phalanx was evaluated in 2 groups (n=10) of cadaveric equine thoracic limbs. In 1 group, the site, direction, and length of the implant were determined by radiography, and in the other group, by CT. Accuracy of screw placement was verified by specimen dissection. Outcomes were (1) absence of penetration of the articular surface, the solar surface, or the semilunar canal (2) appropriate length and direction of the screw. Surgical time was also measured.
Results— No screw penetrated the articular surface, the solar surface, or the semilunar canal in either group. CT was more accurate to identify guidelines for screw insertion (U=23.50, P =.049). With CT, surgical time (mean, 7.7 minutes) was significantly shorter (U=0.000, P =.000) than with radiography (mean, 12.7 minutes).
Conclusion— Standing CT can be used to accurately determine anatomic landmarks for screw insertion in lag fashion in sagittal fractures of the distal phalanx.
Clinical Relevance— This study has a clear clinical relevance for improved internal fixation of sagittal fractures of the distal phalanx. 相似文献
Study Design— Experimental ex vivo study.
Animals— Cadaveric equine thoracic limb pairs (n=10).
Methods— Insertion of a 4.5 mm cortex screw in lag fashion into an intact distal phalanx was evaluated in 2 groups (n=10) of cadaveric equine thoracic limbs. In 1 group, the site, direction, and length of the implant were determined by radiography, and in the other group, by CT. Accuracy of screw placement was verified by specimen dissection. Outcomes were (1) absence of penetration of the articular surface, the solar surface, or the semilunar canal (2) appropriate length and direction of the screw. Surgical time was also measured.
Results— No screw penetrated the articular surface, the solar surface, or the semilunar canal in either group. CT was more accurate to identify guidelines for screw insertion (U=23.50, P =.049). With CT, surgical time (mean, 7.7 minutes) was significantly shorter (U=0.000, P =.000) than with radiography (mean, 12.7 minutes).
Conclusion— Standing CT can be used to accurately determine anatomic landmarks for screw insertion in lag fashion in sagittal fractures of the distal phalanx.
Clinical Relevance— This study has a clear clinical relevance for improved internal fixation of sagittal fractures of the distal phalanx. 相似文献
48.
A. I. Es’kov K. S. Nikol’skii V. V. Ryabkov A. F. Kuzina 《Russian Agricultural Sciences》2009,35(5):328-330
The effect of the physicochemical properties of organogenic materials and additives of bacterial preparations of the genus
Pseudomonas, on the process of composting and properties of the organobacterial fertilizers obtained is investigated. 相似文献
49.
Anoestrus in Dairy Cows: Causes, Prevalence and Clinical Forms 总被引:1,自引:0,他引:1
This article reviews some of the recent advances in veterinary research regarding the causes, prevalence and clinical forms of pathological anoestrus in dairy cows. It is one of the few components responsible for occurrence of postpartum infertility in cattle, expressed in four clinical forms: silent heat, cystic ovarian disease, ovarian afunction and corpus luteum pseudograviditatis. The prevalence of these four forms in different herds is dependent on the managerial, environmental and nutritional status of the farm. Anything, regardless of its nature, that impedes the physiological mechanism involved in oestrus expression is liable to cause anoestrus. Nutrition (energy deficiency), interacted with other factors, is the major cause of this phenomenon (anoestrus). It has direct control of the postpartum anoestrus by negatively affecting the endocrine pathways responsible for proper functioning of the reproductive system through the blockage of pulsatile release of gonadotropin‐releasing hormone in the hypothalamus. Lack of proper training by the stockman substantially contributes to silent heat occurrence. Numerous attempts have been made to prevent or treat pathological anoestrus with exogenous hormones, or nonhormonal remedies like uterine palpation and infusion of Lugol's solution, all of which have produced variable but positive results. Specific treatment for each one of the four clinical forms is briefly outlined. 相似文献
50.
García JM Yousfi K Mateos R Olmo M Cert A 《Journal of agricultural and food chemistry》2001,49(9):4231-4235
Olives (Olea europaea) of the Manzanilla and Verdial varieties, harvested at the green mature stage of ripening, were heated at 30, 40, 45, and 50 degrees C during 24 h and at 40 degrees C during 24, 48, and 72 h, respectively. Just after treatments, oils were physically extracted from the olives. Olive heating promotes a reduction of oil bitterness in direct relationship to the time and temperature used. Fruit heating at < or =40 degrees C during 24 h did not produce significant changes of acidity, UV absorption, peroxide index, panel test score, or oxidative stability of the obtained oils. Both longer treatments at 40 degrees C and heating at >40 degrees C yielded oils with less oxidative stability. Oils obtained from olives heated at > or =40 degrees C showed higher concentrations of chlorophylls and carotenes. For each olive variety, a good correlation between oil bitterness and content of hydroxytyrosol secoiridoid derivatives was found. 相似文献