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31.
A 13-year-old Lusitano stallion was referred to our institution with a history of severe hematuria for 8.5 months. The origin of the hematuria was determined to be the left kidney. The diagnostic workup failed to identify obstructive, infectious, or neoplastic conditions. The history and ultrasonographic examination suggested a chronic condition. The stallion was subjected to left nephrectomy because of the persistent hematuria and anemia. A histopathological examination detected lesions, which were compatible with chronic nephritis and vascular renal hypertension. It is hypothesized that changes in the normal parenchymal architecture produced a vascular aberration that led to renal hypertension, with subsequent blood extravasation and hematuria. The horse recovered completely after nephrectomy.  相似文献   
32.
The aim of this study was to establish the sources of variation in maritime pine wood properties related to appearance and strength, because of the importance of this wood in the sawing industry in Galicia (NW Spain). Ten trees from each of ten plots of the species (i.e., 100 trees) growing in Galicia were felled and sawn to produce the structural planks required for studying the presence of external strength-reducing characteristics. The planks were sampled from the basal logs to 16 m height in the stems, yielding cross sections of target dimensions 100 × 40 mm to 200 × 200 mm. We propose a model in which individual tree height and dominant height are used to predict the knottiness of planks from trees in mature stands. The abundance of externally visible knots on faces and edges of sawn planks is therefore more dependent on the stand location than on the prior silvicultural treatment of the stand.  相似文献   
33.
Primary pulmonary neoplasia is well recognized in dogs and prognosis depends upon the tumor type. The purpose of this retrospective study was to characterize the radiographic appearance of different primary lung tumors with the goal of establishing imaging criteria to separate the different types. Three‐view thoracic radiographs of 74 dogs with histologically confirmed pulmonary anaplastic carcinoma (n = 2), adenocarcinoma (n = 31), bronchioalveolar carcinoma (n = 19), histiocytic sarcoma (n = 21), and squamous cell carcinoma (n = 1) were evaluated. Radiographs were assessed for tumor volume, affected lobe, location within lobe, overall pulmonary pattern, presence of cavitation, mineralization, air bronchograms, lymphadenomegaly, and pleural fluid. Histiocytic sarcomas were significantly larger than other tumor types (271 cm3; P = 0.009) and most likely to be found in the left cranial (38%; 8/21) and right middle (43%; 9/21) lung lobes, whereas adenocarcinomas were most likely to be found in the left caudal (29%; 9/31) lung lobe. Fifty‐seven percent (12/21) of histiocytic sarcomas had an internal air bronchogram. Findings indicate that a large mass in the periphery or affecting the whole lobe of the right middle or left cranial lung lobe with an internal air bronchogram is likely to be an histiocytic sarcoma.  相似文献   
34.
Marine bivalves offer a potentially important source of long-chained polyunsaturated fatty acids (PUFA) for human health supplements. Lipid extracts from individual New Zealand green-lipped mussels (NZGLM) were analyzed as fatty acid methyl esters (FAME) by gas chromatography to assess geographical and seasonal differences between large (86 ± 1 mm) male and female and small (44 ± 1 mm) mussels. PUFAs dominated in spring and summer, comprising ∼ 50% of total fatty acids. Moreover, the commercially important n-3 fatty acids, 20:5n-3 (eicosapentaenoic acid, EPA) and 22:6n-3 (docosahexaenoic acid, DHA) together accounted for 70-79% of total PUFAs in spring and summer. During winter there was a marked decrease in condition and total n-3 PUFAs and a concomitant increase in saturated fatty acids in mussels, suggesting they had already spawned, had increased metabolic demands and limited PUFA-rich phytoplankton as food. While total n-3 content was not significantly different, there were geographical differences in individual n-3 fatty acids. Mussels collected from the cooler waters of Stewart Island had greater levels of 20:5n-3 (EPA), while those collected in Marlborough had greater concentrations of 22:6n-3 (DHA), which was attributed mainly to differences in phytoplankton composition. Total n-3 content and the condition index varied seasonally with greater concentrations of n-3 PUFAs, especially EPA, recorded in large mussels in spring, coincident with spring diatom blooms. Total PUFA levels and condition indices remained high in summer. There was no significant difference in condition indices, total n-3 content, DHA or EPA levels between large male and female mussels. Conversely, large mussels had significantly greater amounts of n-3 PUFAs than small mussels at Marlborough Sounds, while small mussels had marginally greater total n-3 concentrations than large mussels at Stewart Island. Taken together, these results suggest that the NZGLM offers a potentially important source of n-3 PUFAs for human health supplements. Our findings suggest that optimal harvesting conditions occur in spring when mussel condition and n-3 content peak for large mussels. Although DHA and EPA levels varied geographically, total n-3 content was not significantly different between sites, which implies that harvesting mussels for n-3 extracts would be driven more by logistical considerations.  相似文献   
35.
The replacement of gluten in dough products poses a major challenge. Preparing zein doughs in dilute acetic acid and lactic acid, such as produced during sourdough fermentation, was investigated. Increasing acid concentrations (0.7, 1.3 and 5.4% [v/v]) increased zein extensibility and reduced the stress and related parameters. Preparation of zein-maize starch/-rice doughs in dilute organic acids improved dough properties to the extent that the doughs could hold air and be inflated into a bubble by Alveography. Further, they exhibited similar Stability (P), Distensibility and deformation energy (W) to wheat flour dough. Confocal laser scanning microscopy revealed an ordered linear fibril network in zein and zein-rice flour doughs prepared in the dilute acids, which became uniform with increasing acid concentration. SDS-PAGE showed that the acids did not hydrolyse or polymerise the zein. FTIR indicated that the acidic conditions slightly increased the proportion of α-helical conformation in the zein doughs, possibly as a result of deamination. This conformational change may be responsible for the considerably improved zein dough properties. Zein doughs prepared in dilute organic acids show potential as a gluten replacement in gluten-free formulations.  相似文献   
36.
Plant Foods for Human Nutrition - Corn kernels were soaked with different selenium (Se) solutions (0, 12 or 24 mg Na2SeO3/L), sprouted for different times and then lime-cooked for the...  相似文献   
37.
Anterior pituitary gland contents of LH and LHß- and α-subunit mRNAs, and circulating concentrations of LH and testosterone, were determined in bulls treated with the LH-releasing hormone (LHRH) agonist deslorelin. Brahman (Bos indicus) bulls (14-month-old) were allocated to two groups and received the following: Control (n = 5), no treatment; Deslorelin (n = 4), four deslorelin implants (approximately 200 μg total deslorelin/day) for 36 d. Plasma concentrations of LH were higher in bulls treated with deslorelin on Day 1, had returned to typical levels by Day 8, and did not differ for control bulls and bulls treated with deslorelin from Day 8 to Day 29. Pituitary content of LH on Day 36 was reduced (P < 0.001) in bulls treated with deslorelin (33 ± 4 ng/mg) compared with control bulls (553 ± 142 ng/mg). Relative pituitary content of LHß-subunit mRNA was also reduced on Day 36 in bulls treated with deslorelin (Control, 0.65 ± 0.10; Deslorelin, 0.22 ± 0.04; P = 0.003). However, α-subunit mRNA relative content did not differ (Control, 0.73 ± 0.15; Deslorelin, 1.06 ± 0.12; P > 0.05). Plasma concentrations of testosterone were increased over the period of the experiment in the bulls treated with deslorelin compared with control bulls. This is the first demonstration of reduced pituitary content of LHß-subunit mRNA and LH, and unaltered content of α-subunit mRNA, in bulls treated with LHRH agonist. This was associated with apparently typical plasma concentrations of LH and elevated plasma testosterone. The anterior pituitary in bulls treated with LHRH agonist, therefore, undergoes classical desensitization and downregulation, but plasma LH and testosterone are not suppressed.  相似文献   
38.
While the possible negative effect of employer‐sponsored health insurance on labor mobility (job lock) has spawned substantial research, little research has considered differences in job lock between rural and urban areas. Job lock might differ in rural areas because of specific features of rural economies, in particular, the thinness of rural labor markets. This paper estimates measures of job lock for rural and urban areas. Parameter estimates suggest that it is larger in rural areas. The results also indicate that nonwage benefits such as retirement plans, paid vacation, and sick pay are more important factors in married rural workers decisions to change jobs while wages are a more important factor in the transition decisions of single urban workers.  相似文献   
39.
To further understand the impact of urban development on wildlife populations, we examined habitat use and selection by female bighorn sheep Ovis canadensis in two endangered subpopulations near a metropolitan area in southern California. One subpopulation, which had previously been found to have low reproductive success, selected urban environments while the other did not use urban areas. In the subpopulation that used urban areas, females had smaller core activity areas and selected lower elevations and gentler slopes. These females used urban sources of water but a clear relationship between levels of urban use and periods of increased water need was not evident. Diet quality was higher among females that selected urban areas, and this increase was correlated with the level of urban use. Thus, optimal foraging behavior may have contributed to the selection of urban areas. Urban use was lowest during peak months of parturition, suggesting that reproductive strategies may also have influenced temporal patterns of urban use. Although urban areas provided bighorn sheep with forage and water resources, the use of these areas may have substantial costs. For example, females using urban areas had internal parasites that were not found elsewhere in the Peninsular Ranges.  相似文献   
40.
This paper describes a novel device to simulate in vivo aroma release from liquids. This artificial throat simulates the act of swallowing followed by exhalation and shows aroma release curves that are similar in shape to in vivo release profiles. Liquids are poured down a tube, and a thin liquid film remains at the inner wall of the tube. Subsequently, aroma compounds release from this film into a stream of air flowing through this tube, which is analyzed by MS-Nose analysis. The effects of air flow rate, contact time with glass surface, presence of saliva, and addition of whey protein, as well as volume, concentration, temperature, and viscosity of the liquid have been studied and compared with aroma release measurements in vivo. A high level of agreement was found. These results confirm the importance of swallowing for aroma release of liquids, as mentioned in the literature, and the usefulness of the new mimicking device.  相似文献   
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