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61.
Hydrolytic rancidity makes rice bran unsuitable for human consumption, restricting its use to animal feed. To better understand this lipolytic process, bran from rice cultivars ‘Cypress’ and ‘Earl’ differing in oil concentration (23.5 and 18.3 mg of triacylglycerol/100 mg of bran, respectively) was stored at room temperature for five months, and the changes in triacylglycerol content and fatty acid composition, as well as the accumulation of free fatty acids (FFA) were followed. The decomposition of triacylglycerols displayed a decay pattern, with Cypress showing a more elevated degradation rate when compared with Earl. At day 36, both lines reached the same oil concentration, but the triacylglycerol decomposition in Cypress was still higher, indicating that oil concentration may not be a significant factor affecting the intensity of the rancidity process. The higher degradation rate observed in Cypress was apparently caused by higher lipase activity, which was 26% higher (P < 0.001). Fatty acid composition of triacylglycerols changed during storage, the palmitic acid percentage was similarly reduced in both lines to ≈80% of its initial concentration. Oleic and linoleic acids remained almost unmodified or slightly increased. The final content of FFA was ≈58% higher in Cypress than in Earl (P < 0.001). In conclusion, lipase activity appears to be an important factor determining the intensity of the hydrolytic process, but further research is required to confirm this conjecture. If this hypothesis is verified, a selection for lower lipase activity could be useful for increasing rice bran stability.  相似文献   
62.
During the growth season young bulbs may become infected byBotrytis tulipae via the infections present on scales of the planted bulb and from plant stems or by conidia washed down from leaf spots. During storage, infection can only occur after wound inoculation or when bulbs are stored at 100% relative humidity for some days immediately after lifting. There are no perceptible variations in susceptibility or sensitivity of the bulb tunic during growth, whereas the sensitivity of the outer scale is more pronounced during the first weeks after flowering. During storage, the sensitivity of the scale tissue tends to increase in October and November.  相似文献   
63.
Lesions ofBotrytis tulipae on tulip bulbs do not give rise to new infections during storage but may do so after planting. Compared with storage at 20°C and a relative humidity (r.h.) of 40%, storage at 20°C and 95% r.h. reduces, and at 5°C and 95% r.h. tends to increase the rate of successful isolations from lesions during the storage period and the number of new infections after planting. The bulbs show more new infections during growth in soil at 9°C than at 18°C.Samenvatting Lesies, veroorzaakt doorB. tulipae op de buitenste rok van tulpebollen, veranderen niet van uiterlijk tijdens de bewaarperiode. Na het planten kan de schimmel tot aan het bloeitijdstip (waarna geen waarneming aan de moederbol meer mogelijk is) op elk moment, zelfs vlak voor het bloeitijdstip, vanuit de lesies uitgroeien en nieuwe infecties veroorzaken vlak naast de oude lesies of op enige afstand daarvan (Tabel 1). Het is niet bekend of bij deze late uitgroei een remmende factor in of rond de lesies een rol speelt. Bij een aantal lesies groeit de schimmel niet uit, hoewel hij uit enkele daarvan wel kon worden geïsoleerd, zelfs nog omstreeks de bloeitijd.Hoewel in vitro een temperatuur van 20°C en een hoge relatieve vochtigheid (rv) voor de schimmel optimale groeiomstandigheden vormen (Válaková, 1963), bleek dat na bewaring van de bollen bij 20°C en een hoge rv (95%), het uitgroeien vanB. tulipae vanuit de lesies na het planten geringer was dan na bewaring bij 20°C en 40% rv, terwijl bewaring bij 5°C de uitbreiding bevorderde (Tabel 3). Na het planten vond bij lage bodemtemperatuur (9°C) meer uitbreiding van de lesies plaats dan bij hogere. De oorzaak van de verschillen tussen het uitgroeien van de schimmel in vitro en in vivo is niet bekend; misschien blijft de schimmel levenskrachtiger in het bolweefsel bij lage temperatuur of is bij hoge temperatuur een remmende factor meer actief.  相似文献   
64.
Renal blood and plasma flow, glomerular filtration rate (GFR) and maximal tubular transport of PAH (TmPAH) were measured in nonpregnant and twin-pregnant sheep. Twin-pregnant animals were studied during normal pregnancy as well as during ovine pregnancy toxemia artificially produced by starvation. All animals were surgically prepared with aortic, post caval and renal vein cannulas at least one week prior to experimentation. Total renal blood and plasma flow was found to be elevated during pregnancy, but if expressed on the basis of body weight no changes were noted. Starvation and the resultant development of hypoglycemia and hyperketonemia caused a 25-30% decline in renal blood and plasma flow. GFR in pregnant fed sheep (193 ml/min or 2.7 ml/kg.min) was significantly higher (P less than .001) than that of nonpregnant ewes (118 or 2.3 ml/kg min). During ovine pregnancy toxemia the GFR was significantly (P less than .001) diminished (142 ml/min or 2.0 ml/kg min). TmPAH also was significantly higher (179 mg/min or 2.5 mg/kg min) in pregnant animals when compared to nonpregnant ewes (98 mg/min or 1.9 mg/kg min.), but starvation had no effect on Tm PAH in pregnant sheep. It thus appears that a functional renal hypertrophy occurs during pregnancy which is similar to that which follows unilateral nephrectomy or renal disease. During ovine pregnancy toxemia the diminution of renal function probably results from the metabolic derangements and is thus not comparable to human preeclampsia.  相似文献   
65.
Medical records of 144 small-breed dogs (< or =15 kg) and 46 medium- to large-breed dogs (>15 kg) with surgically confirmed, Hansen type I, cervical intervertebral disk extrusions were reviewed. The most common clinical presentation was cervical hyperesthesia. The most common sites affected were the second (C(2)) to third (C(3)) cervical intervertebral disk space in small-breed dogs and the sixth (C(6)) to seventh (C(7)) cervical intervertebral disk space in the larger dogs. Following surgery, 99% of the dogs had resolution of cervical hyperesthesia and were able to ambulate unassisted. Seven (4%) dogs required a second surgery; four of these were large-breed dogs.  相似文献   
66.
A review is given of treatment for 'problem' mares that do not become pregnant. To determine the best therapy, it is necessary to understand the defence mechanisms of the uterus and the pathogenesis of not getting in foal. A thorough clinical examination is absolutely necessary to come to a correct diagnosis. This examination will be explained in a practical way. In the second article the different therapies for treating problem mares are discussed. The therapeutic possibilities vary widely. They can be classified in: anatomical corrections, anti-infectious therapy, and treatment to enhance the uterine defence mechanism.  相似文献   
67.
Robert  Bergman  DVM  Jeryl  Jones  DVM  PhD  Otto  Lanz  DVM  Karen  Inzana  DVM  PhD  Linda  Shell  DVM  Martha  Moon  DVM  R. Eric  Wright  DVM 《Veterinary radiology & ultrasound》2000,41(5):425-432
Post-operative computed tomography (CT) has been described as a technique for diagnosing incomplete resection or recurrence of cerebral neoplasms in humans. The characteristics of immediate postoperative CT images in dogs with intracranial pathology are unknown. This report describes findings from preoperative, immediate post-operative, and 4 week to 9 month follow-up CT examinations in two dogs with histologically-confirmed cerebral meningiomas. In images of one dog after surgery there was mild contrast enhancement of the tissue surrounding the surgical site. This enhancement had resolved in later images and was probably the result of surgically induced trauma. In post operative images of the other dog there was significant hyperattenuation of the tissues around the surgical site. In post contrast images there was increased enhancement that was evident in later images. These findings, although not supported by necropsy, probably indicate incomplete excision of the tumor.  相似文献   
68.
用液体稻食作为猪口粮,可降低10%~17%的成本有数据表明:液体路食可提高猪生产性能,改善其健康状况并降低死亡率70%液体潲食富合碳水化合物如:液体小麦淀粉,乳酪及熟马铃薯度等液体潲食有一些利于贮藏发酵的特点和优势,发酵可能是由于液体潲食所含合成食品和水份所引起.研究人员采用试验研究5种不同液体饲料贮藏6d后的理化特征变化并统计所有可测变化值,如PN值下降到35-3B;乳酸水平上升为15~30g/kg.本文数据综合自几个试验  相似文献   
69.
Rice bran is a rich source of phytochemicals including tocopherols (T), tocotrienols (T3), and γ‐oryzanol that have purported positive effects on human health. The screening of germplasm to determine the genetic diversity influencing contents of these compounds requires knowledge of how sample preparation influences concentrations of the phytochemicals in rice bran. Obtaining this knowledge was the objective of this study. Cultivars with different milling qualities were all milled to different degrees. The differences in bran removal among cultivars decreased as the milling time increased. Samples that were milled for 30 and 40 sec (milled to the degree of 0.23–0.44% surface lipid content [SLC]) showed no significant differences in T and T3 concentrations in the bran within cultivars. Bran starch concentration affected the rankings of cultivars based on phytochemical contents. Expression of the γ‐oryanol concentration in bran after subtracting starch reduced the concentration differences resulting from differences in degree of milling (DOM). Bran from the mature thin kernels had phytochemical contents similar to that of the mature thick kernels milled for 30 sec. The immature thin kernels had significantly lower contents of most of the bran phytochemicals than did the mature kernel fractions.  相似文献   
70.
This study describes a detailed computed tomographic reference of the normal equine foot. Ten forefeet of five adult cadavers, without evidence of orthopaedic disease, were used. Computed tomography (CT) was performed on all feet. Two‐millimetre thick transverse slices were obtained, and sagittal and dorsal planes were reformatted. The CT images were matched with the corresponding anatomic slices. The phalanges and the distal sesamoid bone showed excellent detail. The extensor and flexor tendons (including their attachments) could be clearly evaluated. The collateral (sesamoidean) ligaments could be readily located, but were difficult to delineate at their proximal attachment. The distal digital annular ligament could only be distinguished from the deep digital flexor tendon proximal to the distal sesamoid bone, and its proximal attachment could be identified, but not its distal insertion. Small ligaments (impar ligament, chondrosesamoidean, chondrocoronal and chondrocompedal ligaments, axial and abaxial palmar ligaments of the proximal inter‐phalangeal joint) were seen with difficulty and not at all slices. The joint capsules could not be delineated from the surrounding soft tissue structures. The lateral and medial proprius palmar digital artery and vein could be visualized occasionally on some slices. The ungular cartilages, corium and hoof wall layering were seen. The nerves, the articular and fibrocartilage of the distal sesamoid bone and the chondroungular ligament could not be assessed. Computed tomography of the equine foot can be of great value when results of radiography and ultrasonography are inconclusive. Images obtained in this study may serve as reference for CT of the equine foot.  相似文献   
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