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61.
Ferulic acid (FA) is reported as a good antioxidant absorbed by human or rat but only few data deal with the influence of the food matrix on its bioavailability and with its potential protection against cardiovascular diseases and cancer. Wheat bran is used as a source of ferulic acid, the compound being mainly bound to arabinoxylans of the plant cell walls. Pharmacokinetic profiles of FA and its metabolites are established in rats. Free and conjugated FA quickly appear in plasma, reach a plateau 1 h after intake and remain approximately constant at 1 microM up to 24 h. 2.3% of FA are eliminated in urine. Compared with results obtained after intake of free FA, the presence of FA-arabinoxylans bonds in the food matrix increases the occurrence time of FA in the organism and decreases the level of urinary excretion in 24 h. Nevertheless, sulfated FA is still the main plasmatic form. The antioxidant activity of plasmas of rats fed with a standard diet (containing no FA), pure ferulic acid (5.15 mg FA/kg bw) or bran (4.04 mg FA/kg bw) are measured in an ex vivo test using AAPH as free radical inducer. Plasmas of rats fed with bran show a better antioxidant activity than the control group and the pure FA supplemented group, increasing the resistance of erythrocytes to hemolysis by factors of 2 and 1.5, respectively. These results show the good bioavailability of FA from bran and its potential efficiency to protect organism against pathology involving radical steps of development.  相似文献   
62.
Cell wall composition, pectin, and hemicellulose fine structure variation were assessed in peach and related genotypes with contrasted texture and fruit shape. Cell walls were prepared from four commercial peaches, eight genotypes from the Jalousia × Fantasia peach cross, and six genotypes from the Earlygold peach × Texas almond cross. Sugar composition was determined chemically while fine structure of homogalacturonan pectin and xyloglucan hemicellulose were assessed by coupling pectin lyase and glucanase degradation, respectively, with MALDI-TOF MS analysis of the degradation products. The results indicate clear compositional and structural differences between the parents and their related genotypes on the basis of pectin versus cellulose/hemicellulose content and on the fine structure of homogalacturonan and xyloglucan. A relation between methyl- and acetyl-esterification of pectin with fruit shape is revealed in the Fantasia × Jalousia peach genotypes.  相似文献   
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64.
OBJECTIVE: To use magnetic resonance (MR) imaging to describe and compare the anatomic distribution of a lipid contrast medium injected via the retrobulbar and Peterson nerve block techniques in heads of bovine cadavers. DESIGN: Original study. SAMPLE: 5 grossly normal heads obtained from cattle at necropsy. PROCEDURE: Standardized techniques for the modified retrobulbar and Peterson nerve blocks were established. Each cadaver had 1 treatment performed on a randomly selected side of the head; the second treatment was performed on the alternate side of the head. Injections were performed with canola oil, which is an MR-positive contrast medium. Images of heads in the transverse and dorsal planes were obtained with a 3.0 Tesla short-bore MR system. RESULTS: The retrobulbar technique was characterized by widespread distribution of the contrast medium around the periorbital structures; further distribution of the medium was detected along the optic nerve and in the ethmoid turbinates and nasopharynx. After the Peterson nerve block technique, contrast medium was repeatedly located in the pterygopalatine fossa, but distribution to surrounding structures was minimal. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that the retrobulbar injection technique results in a greater distribution of contrast medium to the target nerves and surrounding structures, compared with that achieved via the Peterson nerve block technique. This may explain the previously reported clinical impression that the retrobulbar block is more reliable than the Peterson nerve block but is associated with a greater risk of complications.  相似文献   
65.

Objectives

Goal-directed fluid therapy (GDFT) based on pulse pressure variation (PPV) was used in anaesthetized dogs undergoing abdominal surgeries. The aims were 1) to evaluate the success rate of the PPV ≥13% in detecting fluid responsiveness [delta stroke volume (ΔSV) ≥10%]; 2) to assess the correlation between PPV, systolic pressure variation (SPV), Plethysmograph Variability Index (PVI) and central venous pressure (CVP) and 3) to establish the threshold value for the PVI that would predict a PPV value of ≥13% and indirectly discriminate responders from nonresponders to fluid therapy.

Study design

Clinical, prospective, interventional study.

Animals

A total of 63 client-owned dogs scheduled for abdominal procedures.

Methods

PPV and SPV were calculated manually from the invasive blood pressure trace on the Datex monitor. PVI was recorded from the Masimo pulse oximeter. Fluid challenge (10 mL kg?1 Compound Sodium Lactate) was performed when PPV was ≥13% and/or mean arterial pressure (MAP) < 60 mmHg. Fluid responsiveness was assessed by the transoesophageal Doppler probe. Cardiovascular parameters (heart rate, MAP, PPV, SPV, PVI, SV and if available, CVP) were measured before and after each fluid intervention.

Results

PPV ≥ 13% reliably predicted fluid responsiveness in 82.9% of cases. There was positive correlation between PPV and SPV (r = 0.84%), PPV and logPVI (r = 0.46) as well as SPV and logPVI (r = 0.45). Noninvasive PVI value ≥13% should predict PPV threshold value (13%) with 97% sensitivity and 68% specificity. There was no statistically significant correlation between PPV and CVP.

Conclusions

PPV is a useful clinical tool to detect occult hypovolaemia and predict cardiovascular response to fluid challenge. Use of PPV is recommended as a part of GDFT in dogs undergoing abdominal procedures.  相似文献   
66.
L. Lahaye  Y. Riou  B. Sve 《Livestock Science》2007,109(1-3):138-140
Two experiments were performed in order to test the effects of grinding and pelleting wheat (experiment 1) or maize (experiment 2) on amino acids (AA) standardized (SID) and true (TID) ileal digestibility. Basal ileal endogenous losses (IEL), used to calculate SID from apparent digestibility, were determined by feeding a protein-free diet. Total IEL required to calculate TID were estimated as the difference between total and dietary losses determined according to the isotope dilution technique using 15N-labeled crops. Wheat and maize were ground to compare two different mean particle sizes (d50 500 μm and 1000 μm). Then, a fraction of the 500-μm mash was further pelleted through two dies of different thicknesses (16 vs. 20 mm for wheat and 16 vs. 24 mm for maize), holes diameter 4 mm in both cases. Cereals were incorporated in 4 isoproteic diets either in mash form (fine vs. coarse mash) or in pelleted form (thin vs. thick die). In experiment 1, wheat was associated with rapeseed meal diets, while in experiment 2, maize was associated with soybean meal. The reduction of wheat particle size affected neither AA SID nor TID. In contrast, the pelleting treatment significantly improved protein and most AA SID and TID. In addition, total IEL of protein and several AA were significantly reduced when the thicker die was used. Numeric improvements of protein and AA SID were observed with reduction of maize particle size and this was associated with a significant decrease in total IEL so that TID was not modified. Further improvements of AA SID and TID occurred with pelleting of maize, without significant effect on IEL regardless of die thickness.  相似文献   
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68.
The definition of a remote system in the monitoring of fin fish shape variability relies on the appropriate shape analysis tools. In this paper, different methods are proposed and compared. Growth trajectories, computed using geometric morphometrics, allow the pattern of size-related shape change and visualize growth allometry to be analyse. Geometric morphometrics is used to describe shape change in three samples (507 5100 days after hatching) of 119 individuals of the Sparid Diplodus puntazzo. The results are potentially interesting but the method still relies on the manual detection of homologous landmarks (coordinates of points located unambiguously on each specimen’s profile or structure) which are basic for such analysis. In an attempt to proceed towards the remote estimation and the automation of data collection, two alternative approaches are tested. In particular, Elliptic Fourier analysis and Bezier function were applied to the same samples, and results compared with geometric morphometrics. Fourier analysis’ growth curves are very similar to geometric morphometrics’ ones and allows for an appropriate visualisation of global shape changes. At the same time, Fourier methods can be applied to remotely and automatically detected profiles. This method is thus considered as the best candidate in the context of automated fish shape monitoring. The Bezier method performed poorly, both in terms of statistical output and shape visualization.  相似文献   
69.
This is a study of the influence of repeated laundering and the use of fabric softener in the context of mechanical properties of fabrics with respect to textile parameters. In the large competitive market of fabric softener, the fabric softener producers claim benefits for fabric hand as well as the mechanical properties of textiles. The main aim of this study is to investigate the influence of ageing and the use of fabric softener on the mechanical properties of textiles during their cradle to grave life with respect to fibre type, fibre fineness, knitting construction and number of wash cycles. The low stress mechanical properties were evaluated by means of the Kawabata Evaluation system for fabric (KES-F) and Universal Surface Tester (UST). The tensile, shear, bending, compression and surface properties and changes in these parameters due to wash-ageing and the use of fabric softener during laundry were evaluated. These mechanical properties or combinations of them are the deciding factors for comfort aspects of apparel during wear. Hence, these mechanical properties need to be correlated with the sensory attributes. In Part I, we examine the change in mechanical parameters due to wash-ageing and the use of softener, while Part II deals with Fuzzy-Logic modelling to correlate these mechanical parameters with sensory attributes.  相似文献   
70.
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