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91.
Weaning rats were submitted during 3 months to complet and balanced diets where only glucidic constituent varied. They were sacrified when fed or after 16 h fasting. 1. The value of intestinal sucrose K(M) is higher in rats fed on glucose dietary than in rats fed on sucrose, fructose or glucose + fructose dietary. These modifications are independant of the states of digestion. 2. The V(MAX) is diversely influenced by the states of digestion: hydric diet increases the V(MAX) in animals fed on sucrose diet when intestinal repletion has the same effect in animals receiving glucose diet. Fructose diet decreases it irreversibility in both cases. 3. Growth of animals is sagging respectively in order from sucrose and glucose diets to glucose + fructose and fructose diets, then weight of organes is unaffected. It was noted that perirenal and epididymal fats are more abundant in rats nourished with glucose diet than with fructose diet. 4. The glucoregulation is correctly effectued in either starved or fed animals and shows an available adaptation of organism in energetic utilisation of various studied sugars. Plasmatic, hepatis and intestinal free fatty acids levels are constant and equal in all series of expements in spite of important variations of reverse fat.  相似文献   
92.
Alcohols in conjunction with BCl3 have been found to be efficient initiating systems for the polymerization of isobutylene in CH2Cl2 solvent. The following alcohols exhibited high initiating activity: tert.-butanol, 1,1-diphenyl ethanol, 2-phenyl-2-propanol, benzhydrol. The organic moiety of the alcohol becomes the head-group of the polyisobutylene formed. The tailgroup of the polymer is a tertiary chlorine most likely because termination is by chlorination by the BCl3OHΘ counter anion.  相似文献   
93.
选用28日龄断奶的三元杂交(杜×长×大)仔猪60头,随机分为饲喂发酵饲料的试验组和不合发酵料的对照组:每个处理3个重复,每个重复10头猪.试验结束前连续收集3天粪便,测定饲料养分的表观消化率;试验结束时前腔静脉采血,测定血清生化指标.结果:试验组比对照组显著降低了料肉比和腹泻指数(P<0.05),日增重提高,但显著不差异(P>0.05);血清碱性磷酸酶显著提高(P<0.05),而血清尿素氮、总蛋白、白蛋白、谷丙转氨酶均没有显著变化(P>0.05).饲料养分的表观消化率(CTTAD)试验组日粮磷的消化率显著提高(P<0.05),粗脂肪消化率显著下降(P<0.05),粗蛋白和钙的消化率提高,但无显著差异(P>0.05).结果表明,发酵饲料有利于提高仔猪的生长性能和饲料养分的表观消化率,对降低仔猪断奶应激性腹泻有较好效果.  相似文献   
94.
European Journal of Wood and Wood Products - The fundamental material properties of coconut wood cross-laminated timber (CLT) were experimentally evaluated with a focus on the effect of the...  相似文献   
95.
Nonalcoholic fatty liver disease (NAFLD) commonly results from excessive dietary fat intake which characterized by obesity and insulin resistance. Wild fruiting body of Antrodia camphorata (AC) was assayed for alleviative effects on NAFLD. An NAFLD animal model was successfully established in male 7-week-old C57BL/6 mice fed with high-fat diet (HFD) for 36 weeks. The HFD mice exhibited obese and impaired glucose metabolism. After an induction of NAFLD syndrome, AC was given for one week via gavage. Mice with AC treatment showed lowered (p < 0.05) serum TG and TC, lowered (p < 0.05) liver TG content, improved (p < 0.05) oxidative status (TBARS values and GSH levels), and ameliorated (p < 0.05) liver damage (AST, ALT, and LDH values). In addition, AC activated (p < 0.05) gene expressions of PPAR-α with its downstream genes in the liver and caused higher (p < 0.05) rectal temperature, which showed AC attenuates hepatic lipid accumulation by promoting lipid oxidation and further suggests the role of AC in energy expenditure. Overall, our findings revealed that AC possesses alleviative effect on NAFLD.  相似文献   
96.
97.
Kinetics and mechanisms of As(III) oxidation by free available chlorine (FAC-the sum of HOCl and OCl-), ozone (O3), and monochloramine (NH2Cl) were investigated in buffered reagent solutions. Each reaction was found to be first order in oxidant and in As(III), with 1:1 stoichiometry. FAC-As(III) and O3-As(III) reactions were extremely fast, with pH-dependent, apparent second-order rate constants, k'app, of 2.6 (+/- 0.1) x 10(5) M(-1) s(-1) and 1.5 (+/- 0.1) x 10(6) M(-1) s(-1) at pH 7, whereas the NH2Cl-As(III) reaction was relatively slow (k'app = 4.3 (+/- 1.7) x 10(-1) M(-1) s(-1) at pH 7). Experiments conducted in real water samples spiked with 50 microg/L As(III) (6.7 x 10(-7) M) showed that a 0.1 mg/L Cl2 (1.4 x 10-6 M) dose as FAC was sufficient to achieve depletion of As(III) to <1 microg/L As(III) within 10 s of oxidant addition to waters containing negligible NH3 concentrations and DOC concentrations <2 mg-C/L. Even in a water containing 1 mg-N/L (7.1 x 10(-5) M) as NH3, >75% As(III) oxidation could be achieved within 10 s of dosing 1-2 mg/L Cl2 (1.4-2.8 x 10(-5) M) as FAC. As(III) residuals remaining in NH3-containing waters 10 s after dosing FAC were slowly oxidized (t1/2 > or = 4 h) in the presence of NH2Cl formed by the FAC-NH3 reaction. Ozonation was sufficient to yield >99% depletion of 50 microg/L As(III) within 10 s of dosing 0.25 mg/L O3 (5.2 x 10(-6) M) to real waters containing <2 mg-C/L of DOC, while 0.8 mg/L O3 (1.7 x 10(-5) M) was sufficientfor a water containing 5.4 mg-C/L of DOC. NH3 had negligible effect on the efficiency of As(III) oxidation by O3, due to the slow kinetics of the O3-NH3 reaction at circumneutral pH. Time-resolved measurements of As(III) loss during chlorination and ozonation of real waters were accurately modeled using the rate constants determined in this investigation.  相似文献   
98.
功能性消化不良(FD)作为功能性胃肠道疾病的一种,其发病机制尚未明晰。研究表明,胃肠道区系微生物紊乱可能是FD发病的主要机制之一。目前治疗功能性消化不良的方法有限,并存在安全性问题。益生菌是一类一定剂量条件下可以调控胃肠道稳态、营养物质消化吸收及机体能量平衡的活性微生物。以肠道微生物为靶点,通过益生菌调节肠道菌群缓解FD有其潜在优势。本文总结益生菌通过调节肠道菌群改善功能性消化不良的研究进展,为益生菌改善消化不良提供参考依据。  相似文献   
99.
Reliable, sensitive, quantitative, and mobile rapid screening methods for pathogenic organisms are not yet readily available, but would provide a great benefit to humanitarian intervention units in disaster situations. We compared three different methods (immunofluorescent microscopy, IFM; flow cytometry, FCM; polymerase chain reaction, PCR) for the rapid and quantitative detection of Giardia lamblia and Cryptosporidium parvum (oo)cysts in a field campaign. For this we deployed our mobile instrumentation and sampled canal water and vegetables during a 2 week field study in Thailand. For purification and concentrations of (oo)cysts, we used filtration and immunomagnetic separation. We were able to detect considerably high oo(cysts) concentrations (ranges: 15-855 and 0-240 oo(cysts)/liter for Giardia and Cryptosporidium, respectively) in 85 to 300 min, with FCM being fastest, followed by PCR, and IFM being slowest due to the long analysis time per sample. FCM and IFM performed consistently well, whereas PCR reactions often failed. The recovery, established by FCM, was around 30% for Giardia and 13% for Cryptosporidium (oo)cysts. It was possible to track (oo)cysts from the wastewater further downstream to irrigation waters and confirm contamination of salads and water vegetables. We believe that rapid detection, in particular FCM-based methods, can substantially help in disaster management and outbreak prevention.  相似文献   
100.
Extracts of 40 species of Chinese medicinal herb from 32 different botanical families were screened for contact, fumigant and feeding-deterrent activities against the two stored-grain insects Sitophilus zeamais and Tribolium castaneum. Thirty Chinese medicinal herbs exhibited insecticidal or feeding-deterrent activities against the two species of insects. Extracts of Artemisia argyi, Dictamnus dasycarpus, Evodia rutaecarpa, Litsea cubeba, Narcissus tazetta var. chinensis, Polygonum aviculare, Rhododendron molle, Sophora flavescens, Stemona sessilifolia, Tripterygium wilfordii, and Torreya grandis were most active.  相似文献   
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