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771.
Barley and canola seeds were sprouted over a 5 day period, in laboratory conditions under room temperature (22°C) and room lighting. Following initial hydration, seeds were kept moist by wetting the germination trays at 9 a.m., 1 p.m. and 6 p.m. daily. A parallel germination experiment using 200 g quantities of seeds in petri dishes was conducted. Starting from the second day of germination, and every day, dishes of germinating seeds were removed, oven-dried, weighed and milled for proximate and chemical analysis. Seeds from the main germination experiment were fed in a digestibility trial to Wistar rats. Results indicated that sprouting was associated with depletion of many nutrients in both barley and canola, the major losses being in respect of dry matter, gross energy and triglycerides. In barley (but not in canola) sprouting was associated with significant increases in crude fiber and diglyceride content. In canola, there were significant losses in lipid content and increases in phytosterol and phospholipid content. Digestibility data showed an enhancement in digestibility of nutrients in barley but not in canola, implying that sprouting improved nutritional quality of barley but not canola.  相似文献   
772.
Cellulase treatment of cellulose fibers needs to be monitored to give proper weight loss without significant strength loss. On-line monitoring of cellulase treatment is presented which can monitor the weight loss of cotton fabrics by measuring differential refractive index in real time. On-line monitoring was tried under the condition where the cellulase treatment of scoured 100% cotton knits would give weight loss of about 6.6% during one hour cellulase treatment. For comanalyses processing solutions with treatment time of 5, 10, 20, 30, 45 and 60 minutes were taken out, and subjected to sugar analyses using total organic carbon (TOC), and dinitrosalicylic acid (DNS) method as well as HPLC analyses. HPLC analyses showed that cellobiose and glucose were the major components resulting from cellulase treatment of cotton fabric. TOC and differential refractive index measurement proved to be linear to total sugar concentration while DNS method result was dependent on the type of sugar. Various sugar concentrations of the processing solutions measured by these methods were compared with HPLC measurements and correlated with the actual weight loss of the cotton fabric processed. The on-line monitoring device using differential refractometer gave a real time signal which was independent of the ratio of cellobiose and glucose but dependent on the total sugar concentration. The device was also non-destructive.  相似文献   
773.
Ever since the ideal forming theory has been developed for process design purposes, application has been limited to sheet forming and, for bulk forming, to two-dimensional steady flow. Here, application for the non-steady case was made under the plane-strain condition. In the ideal flow, material elements deform following the minimum plastic work path (or mostly proportional true strain path) so that the ideal plane-strain flow can be effectively described using the two-dimensional orthogonal convective coordinate system. Besides kinematics, schemes to optimize preform shapes for a prescribed final part shape and also to define the evolution of shapes and frictionless boundary tractions were developed. Discussions include numerical calculations made for a real automotive part under forging.  相似文献   
774.
Isoflurane (ISO) is the most commonly administered feline inhalant anesthetic in North America. A newer agent, sevoflurane (SEVO), may provide faster induction and recovery from anesthesia based on its physical characteristics. Accordingly, we compared some induction and recovery characteristics of ISO and SEVO in healthy cats. Six female DSH cats (17.9 ± 9.0 (mean ± SD) months, 3.7 ± 0.3 kg) received four randomly assigned treatments: ISO for 1 hour (IS), SEVO for 1 hour (SS), ISO for 5 hours (IL), and SEVO for 5 hours (SL). Anesthesia was induced in a chamber into which ISO or SEVO was delivered at 2.7 times the individual's MAC (determined previously) in 6 L minute?1 O2. Measured (Rascal II, Ohmeda) anesthetic concentration was reported after correction using a multiple gas, standard‐defined calibration curve. For induction, time (seconds) from introduction of inhalant to onset of incoordinated movement (IM), recumbency with movement (RM), recumbency without movement, loss of pedal reflex (PD), and intubation (ET) were recorded. Following intubation, anesthesia was maintained for the required time at 1.25 times the individual's MAC. For recovery, time (seconds) from discontinuation of the inhalant (with continuation of O2) to first movement, extubation (EXT), start of incoordinated movement, head‐lift, sternal recumbency (SR), crawl, stand/walk with incoordination, and jump without incoordination were recorded. Esophageal normothermia was maintained. Data were analyzed by paired t‐test (induction) or One‐way Repeated Measures anova followed, when appropriate, by Tukey's test (recovery). p < 0.05 was regarded as significant. For induction, IM was not significantly different between ISO and SEVO (118 ± 28 seconds vs. 104 ± 28 seconds). All other induction times were significantly shorter with SEVO vs. ISO, e.g. RM (181 ± 31 seconds vs. 213 ± 31 seconds), PD (426 ± 68 seconds vs. 504 ± 70 seconds), and ET (434 ± 66 seconds vs. 515 ± 69 seconds). For recovery, there were no differences between ISO and SEVO for any stage of recovery, e.g. EXT (IS 588 ± 163 seconds vs. SS 425 ± 109 seconds), SR (IS 735 ± 215 seconds vs. SS 655 ± 337 seconds), and IL (710 ± 658 seconds vs. SL 807 ± 465 seconds). We concluded that quantitative recovery characteristics did not depend on whether cats are anesthetized with equipotent amounts of SEVO or ISO, but some induction end‐points were reached more quickly with SEVO.  相似文献   
775.
Leukotrienes (LT) and chemokines are important chemotactic compounds in regulating the recruitment and activation of immune cells during pulmonary inflammatory reactions. Results showed that LTC4 release by porcine alveolar epithelial type II cells (AEC IIs) is significantly enhanced by either LTB4 or LPS stimulation. The basal level of IL-8 gene expression in AEC IIs was only 1/3 of that observed in alveolar macrophages (AMs) while AEC IIs expressed a higher basal level of monocyte chemotactic peptide-1 (MCP-1) and also in response to LPS stimulation than do AMs. The increasing basal and LT-induced MCP-1 gene expressions after 8h of incubation were observed in AEC IIs but decreased in AMs. These findings suggest that AEC IIs play an important role in initial inflammatory reactions of the lung by releasing LTC4, and that they also modulate later inflammatory reactions, evidenced by consistent elevation of MCP-1 gene expression after and during exogenous challenge in pigs.  相似文献   
776.
Tetrandrine (TET), a bis-benzylisoquinoline alkaloid from the root of Stephania tetrandra, is known to have anti-tumor activity in various malignant neoplasms. However, the precise mechanism by which TET inhibits tumor cell growth remains to be elucidated. The present studies were performed to characterize the potential effects of TET on phosphoinositide 3-kinase/Akt and extracellular signal-regulated kinase (ERK) pathways since these signaling pathways are known to be responsible for cell growth and survival. TET suppressed cell proliferation and induced apoptosis in A549 human lung carcinoma cells. TET treatment resulted in a down-regulation of Akt and ERK phosphorylation in both time-/concentration-dependent manners. The inhibition of ERK using PD98059 synergistically enhanced the TET-induced apoptosis of A549 cells whereas the inhibition of Akt using LY294002 had a less significant effect. Taken together, our results suggest that TET: i) selectively inhibits the proliferation of lung cancer cells by blocking Akt activation and ii) increases apoptosis by inhibiting ERK. The treatment of lung cancers with TET may enhance the efficacy of chemotherapy and radiotherapy and increase the apoptotic potential of lung cancer cells.  相似文献   
777.
778.
We determined and compared the composition and content of isoflavones in the cotyledon, hypocotyl, and root of 17 soybean sprout varieties grown under dark and light conditions. The total average isoflavone concentrations in 17 soybean sprout varieties were 2167 microg g(-1) (green sprout) and 2538 microg g(-1) (yellow sprout) in cotyledons, 1169 microg g(-1) (green sprout) and 1132 microg g(-1) (yellow sprout) in hypocotyls, and 2399 microg g(-1) (green sprout) and 2852 microg g(-1) (yellow sprout) in roots. There were no significant differences in total isoflavone concentrations between the green and yellow sprouts. However, significant differences in total isoflavone amounts were observed among the three organs, with roots exhibiting the highest total isoflavone concentrations followed by cotyledons and hypocotyls. Total daidzin concentrations of green (775 microg g(-1)) and yellow (897 microg g(-1)) sprouts increased to more than 4 times that in seeds (187 microg g(-1)). Yellow sprouts contained the highest (1122 microg g(-1)) total genistin concentrations, and green (155 microg g(-1)) and yellow (155 microg g(-1)) sprouts had more total glycitin concentrations than seeds. In cotyledons of green and yellow sprouts, genistin, daidzen, and glycitin constituted more than 67%, more than 28%, and less than 4% of the total isoflavone contents, respectively. In hypocotyls, total daidzin represented more than 45% of the total isoflavones, and total glycitin was higher than in cotyledons and roots. Malonylglycoside concentrations were highest in cotyledons, whereas glycoside concentrations were highest in hypocotyls and roots. The high accumulation of isoflavones in roots is consistent with isoflavones serving as signal molecules in the induction of microbial genes involved in soybean (Glycine max) nodulation.  相似文献   
779.
Magnaporthe grisea is a fungal pathogen of rice that forms appressoria that penetrate the outer cuticle of the rice plant. Data from recent studies indicate that M. grisea isocitrate lyase (ICL), a key enzyme in the glyoxylate cycle, is highly expressed during appressorium-mediated plant infection. Bromophenols isolated from the red alga Odonthalia corymbifera exhibited potent ICL inhibitory activity and blocked appressoria formation by M. grisea in a concentration-dependent manner. In addition, these compounds protected the rice plants from infection by M. grisea. Rice plants infected with wild-type M. grisea Guy 11 exhibited significantly lower disease severity with bromophenol treatment than without, and the treatment effect was comparable to the behavior of the Deltaicl knockout mutant I-10. The protective effect of bromophenols and their strong inhibition of appressorium formation on rice plants suggest that ICL inhibitors may be promising candidates for crop protection, particularly to protect rice plants against M. grisea.  相似文献   
780.
Acupuncture analgesia is an important issue in veterinary medicine. This study was designed to elucidate central modulation effects in response to electroacupuncture (EA) at different acupoints. Manganese-enhanced functional magnetic resonance imaging was performed in Sprague-Dawley rats after sham acupuncture, sham EA, or true EA at somatic acupoints. The acupoints were divided into 3 groups: group 1, analgesic acupoints commonly used for pain relief, such as Hegu (LI 4); group 2, nonanalgesic acupoints rarely used for analgesic effect, such as Neiguan (PC 6); and group 3, acupoints occasionally used for analgesia, such as Zusanli (ST 36). Image acquisition was performed on a 1.5-T superconductive clinical scanner with a circular polarized extremity coil. The results showed that there was no neural activation caused by EA at a true acupoint with shallow needling and no electric current (sham acupuncture). When EA at a true acupoint was applied with true needling but no electric current (sham EA), there was only a slight increase in brain activity at the hypothalamus; when EA was applied at a true acupoint with true needling and an electric current (true EA), the primary response at the hypothalamus was enhanced. Also, there was a tendency for the early activation of pain-modulation areas to be prominent after EA at analgesic acupoints as compared with nonanalgesic acupoints. In conclusion, understanding the linkage between peripheral acupoint stimulation and central neural pathways provides not only an evidence-based approach for veterinary acupuncture but also a useful guide for clinical applications of acupuncture.  相似文献   
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