产胆盐水解酶植物乳杆菌降胆固醇作用的研究

采用茚三酮显色法测定了5株具有潜在益生特性的植物乳杆菌的胆盐水解酶(BSH)活性,采用邻苯二甲醛法测定了发酵上清液、菌体洗涤液和菌体破碎液中胆固醇含量,并对二者进行了相关性分析。结果表明,5株菌的BSH比活力为0.0149~0.0299U/mg总蛋白,去除胆固醇能力为37.64~47.88μg/mL。5株乳杆菌BSH活性与菌体洗涤液中胆固醇含量呈显著正相关,推断是菌株BSH水解结合胆盐生成游离胆酸,后者与胆固醇共沉淀,从而达到降胆固醇的效果。上述研究结果为利用益生菌生产具有降胆固醇功效的产品提供了理论依据。     

Hepatic drug metabolism in rats: impairment in a dirty environment

Reduction of aniline hydroxylase activity, ethylmorphine N-dementhylase activity, and cytochrome P-450 content occurred in hepatic microsomes of rats kept under dirty conditions, defined as accumulation for 1 week of urine and feces in pans under the wire mesh cages. In comparison with rats that had urine and feces removed twice daily from such pans, rats kept over Kimpak bedding or over Litter Green, changed twice daily, also showed reduced drug-metabolizing activity in hepatic microsomes, but to a lesser degree than the dirty rats. Placement of a filter top on cages for 1 week also decreased drug-metabolizing activity. These experiments suggest that the relative cleanliness of an animal's environment can influence hepatic microsomal drug metabolism.     

Microwaves: effect on thermoregulatory behavior in rats

Rats, with their fur clipped, pressed a lever to turn on an infrared lamp while in a cold chamber. When they were exposed to continuous-wave microwaves at 2450 megahertz for 15-minute periods, the rate at which they turned on the infrared lamp decreased as a function of the microwave power density, which ranged between 5 and 20 milliwatts per square centimeter. This result indicates that behaviorally significant levels of heating may occur at an exposure duration and intensities that do not produce measurable changes in many other behavioral measures or in colonic temperature. Further study of how microwaves affect thermoregulatory behavior may help us understand such phenomena as the reported "nonthermal" behavioral effects of microwaves.     

Ribonucleic acid: effect on conditioned behavior in rats

Acquisition of a behavioral response motivated by shock was enhanced in rats chronically treated with yeast ribonucleic acid, and resistance to extinction was greater in rats so treated than in controls. This extends the role of ribonucleic acid to include a behavioral effect in laboratory mammals treated with a purified preparation from yeast.     

Magnesium pemoline: effect on avoidance conditioning in rats

Rats administered 20 milligrams of magnesium pemoline per kilo gram of body weight learned to avoid shock in a jump-out apparatus in fewer trials than did controls. However, the results suggested that the principal effect of the drug was to facilitate the avoidance behavior of those animals that tended to "freeze" in response to electric grid shock. No differences in retention were observed between experimental and control animals that had achieved equal levels of learnine.     

高效降胆固醇植物乳杆菌的筛选及其益生潜能初探

为筛选出高效降胆固醇乳杆菌,挖掘其潜在益生功能,从民间自制泡菜样品中分离乳杆菌,采用邻苯二甲醛法筛选高效降胆固醇菌株,利用16S rDNA进行分子生物学鉴定,并通过耐酸、耐胆盐及抑菌性实验,测定菌株的益生潜能。结果表明:1)从分离出的11株乳杆菌中筛选出PL2、PL5、PL16和PL194等4株高效降解胆固醇菌株,其体外胆固醇降解率分别为48.22%、51.67%、48.43%和48.56%;2)结合菌落特征、部分生理生化试验及16S rDNA基因序列比对鉴定4株乳酸菌均为植物乳杆菌(Lactobacillus plantarum);3)该4株乳酸菌均可在pH2.0的环境下生存3h,菌株PL2和PL5可以在0.3%的胆盐浓度下存活3h;4)菌株PL5对致病性大肠杆菌、沙门氏菌、金黄色葡萄球菌和福氏志贺氏菌均有显著的抑制作用。总之,植物乳杆菌PL5是具有开发前景的高效降胆固醇益生菌。     

Cyclophosphamide: effect on experimental allergic encephalomyelitis in Lewis rats

Lewis rats sensitized to spinal cord in adjuvant and exhibiting advanced clinical paralytic signs of experimental allergic encephalomyelitis were treated with cyclophosphamide (5 milligrams per kilogram) daily. Of 30 treated animals, 21 recovered rapidly and appeared clinically well within 7 to 12 days. This immunosuppressive agent may prove therapeutically useful in the treatment of autoimmune diseases.     

脱氢表雄酮对幼年大鼠脂类代谢的影响

选用健康雄性SD大鼠40只,随机分为4组,每组10只。对照组腹腔注射50％乙醇＋50％丙二醇混合液,3个试验组分别经腹腔注射1、5和10mg·kg。的脱氢表雄酮（DHEA）溶液。每隔1d注射1次,连续7次。试验结果表明,DHEA能够降低幼年期大鼠腹脂率、血清甘油三酯（TG）、非酯化脂肪酸（NEFA）的水平,对血清中胆固醇（TC）水平没有显著影响;高剂量的DHEA可显著降低肝脏组织中脂蛋白脂酶（LPL）和肝脂酶（HL）的活性。不同浓度的DHEA均可显著降低血清中胰岛素和TNF-α的水平,具有增加胰高血糖素的趋势。DHEA能显著降低肝脏中糖原、TC水平,对TG没有影响,但DHEA可显著增加肝脏中Na＋-K＋-ATP酶活性。提示,DHEA具有降低幼年期大鼠脂肪蓄积的作用。     

p,p'-DDT: effect on calcium metabolism and concentration of estradiol in the blood

Ringdoves given 10 parts per million p,p'-DDT showed a decrease of estradiol in the blood early in the breeding cycle and egg-laying was delayed. There was also a decrease in deposition of medullary calcium and in eggshell weight. Injection of p,p'-DDE (150 milligrams per kilogram of body weight) caused reduction of eggshell weight and inhibition of carbonic anhydrase in the oviduct.     

Protective effect of high-oleic acid peanut oil and extra-virgin olive oil in rats with diet-induced metabolic syndrome by regulating branched-chain amino acids metabolism

High-oleic acid peanut oil(HOPO) and extra-virgin olive oil(EVOO) have been reported previously to have an attenuating effect on metabolic syndrome(MS). This study aimed to evaluate the metabolic effect of HOPO and EVOO supplementation in attenuating MS and the role of gut microbiota in regulating the metabolic profile. Sprague-Dawley rats were continuously fed with a normal diet, high-fructose and high-fat(HFHF) diet, HFHF diet containing HOPO, or a HFHF diet containing EVOO for 12 weeks. The m...     

Changes in intensity of punishment: effect on running behavior of rats

Changing the strength of punishment produced only minor changes in rats' speed of running to food and shock at the goal of an alley. The persistence of running behavior after increased or decreased shock intensity is attributed to a stereotyped withdrawal response conditioned at the goal during initial punishment training.     

饥饿和恢复投喂对牙鲆代谢的影响

2003年3月26日～4月30日,对体重(5 93±1 20)g、全长(8 58±0 39)cm的牙鲆Par alichthysolivaceus(TemmincketSchlegel),在(20±1)℃条件下进行饥饿和恢复喂食试验,研究饥饿和恢复喂食对牙鲆代谢的影响。结果表明,随着饥饿时间的延长,牙鲆的代谢率明显地呈直线下降,由试验开始的291 31mg/(kg·h)(以O2计,下同)饥饿15d后下降至135 42mg/(kg·h)(O2),下降了53 5%;恢复喂食后,牙鲆的代谢率明显升高,饥饿5d组(S5)在恢复喂食的第5d,代谢率恢复到对照组水平,饥饿10d组(S10)在试验结束时接近对照组水平,而饥饿15d组(S15)在试验结束时代谢率仍大大高于对照组。在恢复喂食期,牙鲆耗氧率与饥饿处理时间总体上呈正比,即饥饿处理时间越长,牙鲆的耗氧率越高。     

饥饿和恢复投喂对牙鲆代谢的影响

2003年3月26日～4月30日,对体重(5 93±1 20)g、全长(8 58±0 39)cm的牙鲆Par alichthysolivaceus(TemmincketSchlegel),在(20±1)℃条件下进行饥饿和恢复喂食试验,研究饥饿和恢复喂食对牙鲆代谢的影响。结果表明,随着饥饿时间的延长,牙鲆的代谢率明显地呈直线下降,由试验开始的291 31mg/(kg·h)(以O2计,下同)饥饿15d后下降至135 42mg/(kg·h)(O2),下降了53 5%;恢复喂食后,牙鲆的代谢率明显升高,饥饿5d组(S5)在恢复喂食的第5d,代谢率恢复到对照组水平,饥饿10d组(S10)在试验结束时接近对照组水平,而饥饿15d组(S15)在试验结束时代谢率仍大大高于对照组。在恢复喂食期,牙鲆耗氧率与饥饿处理时间总体上呈正比,即饥饿处理时间越长,牙鲆的耗氧率越高。     

Weaning of young rats: effect of time on behavior

Male rats were weaned on the 15th, 16th, 17th, 25th, and 30th day of postnatal life. The rate of elaboration of the conditioned reflex at 8 months of age and the stability of the memory trace at 12 months were studied. Compared with rats weaned at 30 days of age, those weaned on day 15 elaborated the conditioned reflex much more slowly and the memory trace was less firm. Rats weaned on days 16 and 17 elaborated the conditioned reflex more quickly than rats weaned on day 15 but more slowly than those weaned on day 30. In all groups the memory trace showed the same stability and was significantly firmer than in rats weaned on day 15. The higher nervous activity of rats weaned at the age of 25 days more nearly resembles that of rats weaned at 15 days than the 30th day.     

Cigarette smoking: stimulatory effect on metabolism of 3,4-benzpyrene by enzymes in human placenta

The enzymatic hydroxylation of 3,4-benzpyrene was not detected in human placentas obtained after childbirth from nonsmokers, whereas this enzyme activity was present in placentas obtained from individuals who smoked cigarettes. The degree of induction of benzpyrene hydroxylase caused by cigarette smoking varied in different individuals. Treatment of pregnant rats with benzpyrene increased the activity of this hydroxylase in the placenta.     

硒对山羊瘤胃消化代谢影响的体外研究

用３只装有永久性瘤胃瘘管的本地空怀母山羊,于晨饲后３ｈ采瘤胃液,置人工瘤胃中培养。结果表明,培养液添加硒不影响瘤有液ＰＨ值,但可提高瘤胃发酵水平,使总挥发性脂肪酸含量趋于增加,乙酸和丁酸比例明显降低,丙酸比例显著升高,Ｃ２／Ｃ３明显降低。