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51.
Embolic pulmonary aneurysms in yearling feedlot cattle   总被引:2,自引:0,他引:2  
Throughout all of 1974, we surveyed, for illnesses and deaths, about 407,000 yearling feedlot cattle. Of 1,988 cattle necropsied, 25 (1.3%) had ruptured pulmonary aneurysms and an additional 4 had gross pulmonary emboli without rupture. The emboli originated from thrombi in the caudal vena cava where that vessel closely applies to the left border of the liver and where parenchymal abscesses had developed. The emboli had lodged in the pulmonary artery, weakened its wall, and led to saccular aneurysms. Infection weakened and blood pressure ruptured the saccule and opened the adjacent bronchi. Extravasated blood dissected the tunica adventitia, formed hematomas, poured into the bronchus, and was expelled from the larynx. A portion was swallowed into the rumen, and some was coughed and blown from the nose and mouth. Deaths were attributed to exsanguination and pulmonary incapacitation.  相似文献   
52.
Investigated the importance of supportive behavior by an authority figure when setting goals, using a brainstorming task. 90 college students were randomly assigned in a 2?×?3 design to a supportive or nonsupportive condition and to 1 of 3 goal-setting conditions (assigned, participative, and "do your best"). Goal difficulty was held constant between the assigned and the participative conditions. Supportive behavior resulted in higher goals being set than nonsupportive behavior. Participation appears to be important in that it increases understanding of task requirements. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
Tofu was made by substituting kenaf seed (K) with soybean (S) at 100 (positive control), 50%, 40%, 30%, 20%, 10% and 0% (negative control). The results indicated that kenaf seed substitution at all ratios significantly increased the soluble solids and protein content of the milky extracts. The yield, moisture and protein content of the tofu were significantly increased with the increase in kenaf seed substitution, while the lipid content was significantly decreased. The tofu made with kenaf seed substitution of 50%, 40% and 30% had the same protein content (43.76–45.36 g/100 g) with the positive control (45.36 g/100 g), but a significantly higher lipid content (32.00–35.75 g/100 g) than that of the positive control (27.50 g/100 g). The microstructure of the tofu revealed that only the positive control had a honey-comb structure, whilst the tofu made from kenaf seed-soybean blends had a pseudo-honey like structure. Up to 30% of soybean can be added into the kenaf-based tofu, without any negative effect on the textural and colour properties and, protein content, but significantly improved the essential amino acids content of the kenaf-based tofu. Therefore, the blend of 70K:30S ratio using 0.5 g% glucono delta-lactone as a coagulant is recommended to produce kenaf seed-soybean tofu.  相似文献   
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The ability of Leuconostoc mesenteroides DU15 to produce antifungal peptides that inhibit growth of Aspergillus niger was evaluated under optimum growth conditions of 30 °C for 48 h. The cell‐free supernatant showed inhibitory activity against A. niger. Five novel peptides were isolated with the sequences GPFPL, YVPLF, LLHGVPLP, GPFPLEMTLGPT, and TVYPFPGPL as identified by de novo sequencing using PEAKS 6 software. Peptide LLHGVPLP was the only positively charged (cationic peptides) and peptide GPFPLEMTLGPT negatively charged (anionic), whereas the rest are neutral. The identified peptides had high hydrophobicity ratio and low molecular weights with amino acids sequences ranging from 5 to 12 residues. The mode of action of these peptides is observed under the scanning electron microscope and is due to cell lysis of fungi. This work reveals the potential of peptides from L. mesenteroides DU15 as natural antifungal preservatives in inhibiting the growth of A. niger that is implicated to the spoilage during storage.  相似文献   
57.
Nitrofuran antibiotics were previously used in animal healthcare but are now prohibited. Semicarbazide is a breakdown product of 5-nitrofurazone and protein-bound semicarbazide is used as a marker residue for the illegal use of 5-nitrofurazone. However, the presence of the prohibited semicarbazide has been reported in some food items of animal origin. A novel observation is reported that semicarbazide can be detected in Finnish crayfish samples, i.e. crustacea, never medicated with nitrofurazone. The origin of the semicarbazide is presently unknown. Positive identification was undertaken by liquid chromatography coupled with tandem mass spectrometry detection. The level of semicarbazide was determined as the protein-bound form as well as the total amount of semicarbazide in the sample. The average levels of total semicarbazide and the protein-bound form were 4.2 and 0.5 ng g(-1) fresh crayfish meat, respectively. All the tested samples (n = 18) contained traces of semicarbazide, the highest amount being 12 ng g(-1) fresh crayfish meat.  相似文献   
58.
Polyphenols in cocoa products determine the astringent sensation due to their interaction with salivary proline‐rich protein. Changes in the ability of polyphenols to produce astringency during cocoa roasting have been studied through an evaluation of the polyphenol–protein interaction in cocoa cake/liquor roasted at 120 °C for 45 min, with and without enrichment with polyphenol extract. Roasting decreased the capacity of polyphenols to interact with protein, causing a decrease in astringency. However, the polyphenol–protein interaction products after roasting could still be oxidized enzymatically and most probably would still give cocoa products beneficial effects as functional food. Copyright © 2005 Society of Chemical Industry  相似文献   
59.
Crude extracts of root, leaf and fruit of Morinda citrifolia were fractionated on a Sephadex LH-20 column with ethanol as eluate. Based on UV absorption intensity of phenolic compound (725 mm) the Sephadex LH-20 column was able to separate fruit, leaf and root extracts into six, five and five fractions, respectively. The results showed that all the fractions tested exhibited considerably high antioxidative activity in the ferric thiocyanate assay and thiobarbituric acid test and the activities of some of the fractions were as good as those of either tocopherol or BHT. The fractions from different parts of the plants were found to contain different amounts of total phenolic compounds, which, interestingly, do not correspond to the antioxidative activity measured. This is probably due to the presence of different phenolics in the samples, with different antioxidative activities which involves various mechanisms inhibiting the oxidation process. The study suggested that root, leaf and fruit of M. citrifolia might contribute significantly to exogenous antioxidant which is crucial in combating oxidative stress.  相似文献   
60.
Milk antitrypsin reflects leakage of protein of blood plasma into milk. Mastitis detection can be based on measurement of the trypsin-inhibitor capacity in milk; the "Eflab Mastitis Test" procedure is based on this principle. The procedure was developed to screen for subclinical mastitis; high capacity and sensitivity permits whole herds to be analyzed on a quarter basis to identify inflamed quarters during a single sampling. Milk antitrypsin was measured on 2174 quarter milk samples by a colorimetric procedure. The Multiskan MC reader was hooked to desk computer to interpolate antitrypsin from the standard curve and to analyze results. The analysis of inflammation was based on antitrypsin as well as computerized interquarter evaluation. These measures were compared with bacteriologic study of milk to set criteria for automatic identification of mastitis in individual quarters. The comparison against the lowest teat antitrypsin gave better indication of infection than antitrypsin as such. By strict criteria that identified inflammations caused by major pathogens, 18.8% of uninfected quarters were identified as false positive. The explanation is that a single bacteriological culture is not reliable for detecting mastitis, because there are temporary causes of tissue irritation other than bacteria that may be identified during standard bacteriologic examination.  相似文献   
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