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排序方式: 共有98条查询结果,搜索用时 15 毫秒
1.
2.
Hepatic lipid characteristics and histopathology of laying hens fed CLA or n−3 fatty acids 总被引:2,自引:0,他引:2
The effect of dietary CLA and n−3 PUFA on hepatic TAG accumulation, histopathology, and FA incorporation in lipid classes
by laying chickens was investigated. One hundred twenty 30-wk-old single-comb white leghorn laying hens were distributed randomly
to four treatments (3 replications of 10 birds) and were fed diets containing CLA and animal fat (Diet I), 18∶3n−3 (Diet II),
or long-chain n−3 FA (Diet III). A sunflower oil (n−6 FA)-based diet was the control. Feeding Diet I resulted in an increase
in hepatic total lipids (P<0.05). The liver TAG content was 32.2, 18.9, 29.4, and 18.7 mg/g for hens fed Diet I, Diet II, Diet III, and the control
diet, respectively (P<0.05). The serum TAG was lowest in bilds fed Diet II (P<0.05). Diet I resulted in an increase in the total number of fat vacuoles and lipid infiltration in hepatocytes (P<0.05). The number of cells with 75% or higher lipid vacuolation was observed only in birds fed Diet I. Feeding diets containing
CLA resulted in an increase in the content of the c9,t11 CLA isomer in liver TAG and PC (P<0.05). No difference was observed in the CLA concentration of hepatic PE fractions. The content of DHA (22∶6n−3) was higher
in the TAG, PC, and PE of hens fed Diet II and Diet III than Diet I and the control (P<0.05). Feeding CLA resulted in an increase in total saturated FA in the TAG and PC fractions (P<0.05). Long-term feeding of CLA in laying birds leads to an increase in liver TAG and may predispose birds to fatty liver
hemorrhagic syndrome. 相似文献
3.
4.
S Verghese A Mullasari P Padmaja P Sudha MC Sapna KM Cherian 《Canadian Metallurgical Quarterly》1998,50(4):418-422
This study examines the long-term prognosis of patients with an abnormal exercise radionuclide angiogram in the absence of significant angiographic coronary artery disease (CAD). In general, patients without significant CAD have an excellent prognosis, but the long-term outcome for the subset of patients with an "ischemic" exercise test is not known. In this study, 161 patients with normal coronary arteries or insignificant CAD (< 50% left main and < 70% left anterior descending, left circumflex, or right), resting left ventricular (LV) ejection fraction > or = 0.50, and an abnormal exercise radionuclide angiogram (LV ejection fraction that decreased with exercise or peak exercise LV ejection fraction < 0.60) were followed for a median duration of 11.3 years. The mean delta LV ejection fraction was -0.07, 98 patients (61%) had a decrease in LV ejection fraction of > or = 5 units, and 40 patients (25%) had peak exercise LV ejection fraction < 0.50. During follow-up there were 19 deaths (only 1 of which was cardiac), 7 nonfatal myocardial infarctions, and 9 revascularization procedures. At 12 years, overall survival was 88%, better than the expected survival for the age- and sex-matched general population. Survival free of cardiac death or myocardial infarction was 94% and survival free of any cardiac event including revascularization was 88%. Thus, patients with an abnormal exercise radionuclide angiogram but without significant CAD have an excellent long-term prognosis. 相似文献
5.
The effect that egg yolk or maternal n−3 FA have on the cardiac tissue long-chain n−3 FA status of chicks during growth was
investigated. Fggs with low, medium, and high levels of n−3 PUFA were obtained by feeding breeder hens a wheat/soybean meal-based
diet containing 5% sunflower oil (Low n−3), 2.5% sunflower oil plus 2.5% fish oil (Medium n−3), or 5% fish oil (High n−3).
The chicks hatched from Low, Medium, and High n−3 eggs were fed a diet containing 18∶3n−3, but devoid of long-chain n−3 FA.
The FA composition of cardiac tissue was determined on days 0, 14, 28, and 42. At day 0, the cardiac FA reflected maternal
diet. With time, the level of all the long-chain n−3 FA decreased compared with day 0, and this was true especially by day
14. These data show that dietary 18∶3n−3 fed to the chicks did not sustain high levels of EPA and DHA in cardiac tissue, despite
the high content of long-chain n−3 FA in the maternal diet. At days 0 and 14, the chicks hatched from High and Medium n−3
eggs had higher 20∶5n−3, 22∶5n−3, and 22∶6n−3 contents with a concomitant reduction in 20∶4n−6 in the cardiac tissue compared
with the Low n−3 egg group. Cardiac tissue of birds hatched from Medium n−3 eggs retained higher levels of 20∶5n−3 up to day
42 of growth when compared with other treatments (P<0.05). None of the treatments was effective in maintaining DHA levels after day 14 of growth. 相似文献
6.
Plant sources of omega-3 fatty acids (FA) are needed that can materially raise tissue levels of long-chain omega-3 FA [i.e.,
eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 20:6n-3)]. Stearidonic acid (SDA; 18:4n-3) is the delta-6
desaturase product of alpha-linolenic acid (ALA; 18:3n-3), and when fed to humans, increases red blood cell (RBC) content
of EPA to a greater extent than does ALA. This study was undertaken to determine the dose-dependence and time course of the
increase in the EPA and DHA content of the heart and RBC in dogs. Adult male Beagles were fed 21, 64, or 193 mg/kg of SDA
in in their food daily for up to 12 weeks. Positive and negative controls were given EPA (43 mg/kg) or high oleic acid sunflower
oil, respectively. The baseline EPA content of RBC was 0.38 ± 0.03% which increased (P < 0.01) in a dose-dependent manner, with the high dose of SDA and EPA achieving levels of 1.33 ± 0.26 and 1.55. ± 0.28%,
respectively. In the heart, the content of EPA rose from 0.06 ± 0.01 to 1.24 ± 0.22% in the EPA group and to 0.81 ± 0.32%
in the high SDA group (both P < 0.01). In both tissues, DHA did not change. Compared to dietary EPA, SDA was 20–23% as efficient in raising tissue EPA
levels. In conclusion, SDA supplementation increased the EPA content of RBC and heart and may have utility as a plant-based
source of omega-3 FA. 相似文献
7.
Hybridization of Banana fibers with glass fibers has been found to reduce the water absorption behavior of the composites in an earlier work by us. Banana fibers were hybridized with glass and different layering patterns were followed in the preparation of the composites. The effect of the various layering patterns on the water absorption of the composites was studied. It was found that water diffusion occurs in the composite depending on the layering pattern as well as the temperature. In all the experiments, it has been found that composites with an intimate mixture of glass and banana show the maximum water uptake except for temperature of 90°C. At 90°C the maximum water uptake is found to be for composites where there is one layer of banana and another layer of glass. The water uptake follows the same trend as that in all other temperatures till a time span of 4900 min is reached. The kinetics of diffusion was found to be Fickian in nature. The various thermodynamic parameters like sorption coefficient, diffusion coefficient. Enthalpy change, entropy change, and activation energy of the various composites were calculated. From all the calculations it has been concluded that layering pattern is an important parameter which controls the water absorption of the composites. The layering pattern Cg‐b‐g was found to have the lowest water uptake. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
8.
BACKGROUND: Pleural biopsy is invaluable for the etiological diagnosis of pleural diseases in the presence of an exudative pleural effusion. Conventionally, pleural biopsy is either performed with the Cope's or the Abrams pleural biopsy needles. A few investigators have used the Tru-cut biopsy needle with or without ultrasound guidance. We report our experience in performing closed pleural biopsy using a Tru-cut needle without ultrasound guidance in moderate to large exudative pleural effusion. We used a perpendicular approach to biopsy the pleura instead of the tangential approach described earlier. METHODS: Closed Tru-cut biopsy was performed in 27 consecutive patients with exudative pleural effusion who volunteered to undergo the procedure. The biopsy specimen was sent for histopathology. Pleural fluid analysis and other relevant investigations required to obtain a specific diagnosis were carried out. RESULTS: A specific diagnosis of tuberculosis was obtained on histopathology of pleural tissue in 12 out of 16 patients (diagnostic yield 75%) and in 5 out of 7 patients with malignancy (diagnostic yield 71%). Among the other 4 patients, other causes of exudative pleural effusion were detected in 3 and in 1 patient, no specific diagnosis could be made, despite extensive investigation. CONCLUSION: Closed pleural biopsy using a Tru-cut needle is effective for the specific diagnosis of exudative pleural effusion. The use of a perpendicular approach to biopsy the pleura does not seem to increase the complication in moderate to large pleural effusion. 相似文献
9.
10.
Jesse T. Cherian David G. Castner Robert M. Fisher 《Journal of Materials Engineering and Performance》2002,11(6):603-609
Disbonded lap-shear specimens were analyzed to determine the locus of failure within bonded titanium (Ti) sol-gel polyimide
joints. Bonded Ti alloys are being evaluated for use at an operating temperature of 175 °C. Determining the locus of failure
for bonded Ti lap-shear specimens is part of a larger effort to develop durable, environmentally safe surface treatments for
Ti alloys. Surface-treated Ti alloy (Ti-6Al-4V) plates are bonded in a standard lap-shear specimen configuration and exposed
to temperature for specified intervals. The lap-shear bond joint consists of two etched Ti panels coated with a silicon and
zirconium containing sol-gel, primed with a polyimide, and then bonded together with adhesive and supporting scrim material.
The lap-shear specimens are tested for overall strength and failure modes. Specimens with adhesive failure modes were examined
with x-ray photoelectron spectroscopy (XPS) to determine the composition of the bond joint failure layer. Analysis shows that
the failure was located closer to the sol-gel/polyimide interface than to the Ti/sol-gel interface. Transmission electron
micrographs (TEM) of the cross-sectioned joint confirmed the chemical distribution determined from the XPS data. 相似文献