Epostane抑制恒河猴黄体期孕酮水平

Epostane〔(4α,5α,17β)-4,5-桥氧-3,17-二羟-4,17-二甲基雄甾-2-烯-2-腈,win32729〕有抑制黄体作用,在体外,它可竞争性抑制3B-羟甾体脱氢酶活性,后者能促使娠烯醇酮转化为孕酮。本文报告了Epostane对正常和注射hCG的恒河猴黄体期孕酮(P)的影响。研究采用雌性成年恒河猴。Epostane对正常黄体期P水平的影响,使用22只行经的恒河猴,用药前周期为26～30天,用药前3个周期中至少一个周期第16、17、18天血P≥2.0ng/ml。从周期第18天起6只猴每天用赋形剂,6只猴每天给Epostane25mg,5只猴每天给Epostane 50mg,另5只猴     

细胞工厂制备冻干甲型肝炎减毒活疫苗猴体安全性和免疫原性研究

[目的]了解细胞工厂和转瓶工艺生产的冻干甲型肝炎减毒活疫苗免疫恒河猴后的安全性和免疫原性。[方法]用静脉注射的方式为恒河猴接种疫苗,观察恒河猴的临床症状、体征、生化、免疫学反应以及肝组织的病理变化。[结果]细胞工厂和转瓶工艺生产的冻干甲型肝炎减毒活疫苗均未见临床症状和体征的异常改变,ALT正常,抗-HAV在观察期内持续阳性,肝组织无病毒性肝炎的病理性改变。[结论]细胞工厂和转瓶工艺生产的冻干甲型肝炎减毒活疫苗对恒河猴的免疫效果相同,具有良好的保护作用。     

混合稀土对恒河猴的急性毒性研究

本文研究了混合稀土经消化道和静脉注射对恒河猴的急性毒性作用。结果表明,混合稀土硝酸盐灌胃可引起动物呕吐,半数有效量为68.1mg/kg。500mg/kg/d掺入饲料喂饲可使动物拒食和大便硬结。静脉注射混合稀土可产生溶血(急性阈浓度为2mg/kg)、抗凝作用(阈浓度为1mg/kg)剂量达20mg/kg时,具有肝、肾损害及影响钙、磷代谢。     

关于液化石油气最高容许浓度的建议

通过对605名液化石油气作业工人的调查表明，工人接触浓度为1500－2000mg/m^3时，出现某些神衰症状的发生率明显增高，其他各项指标均与接触浓度及接触工龄没有关系。急性吸入毒性研究，大小鼠的最大耐受浓度大于277362.27 mg/m^3，急性阈浓度大于170389.95mg/m^3。恒河猴和小鼠的慢性阈浓度均为31000mg/m^3。Ames试验阴性。建议液化气的最主容许浓度为1000mg/m^3，经全国劳动卫生标准分委员会审议通过。     

恒河猴脱离铅接触后的毒性反应及生殖机能影响的远期观察

本文报道了醋酸铅对雌性恒河猴亚急性毒性和生殖机能的远期影响。结果表明,10～50mg/kg剂量的铅可引起雌猴消化和神经系统机能的障碍,红细胞游离原卟啉(FEP)和点彩红细胞增高,血红蛋白下降。铅可引起多个器官的损害,尤其以肾、肝两脏器为明显。铅对雌猴生殖机能的影响主要为:月经持续时间减少,月经周期延长和受孕率低等等。     

空巢孩子何时不孤单

<正>心理学实验:被隔离的恒河猴心理学家亨利·哈罗曾用幼年恒河猴做过类似"早期母爱被剥夺"的实验,除了保证其生理需要以外,不让刚出生的恒河猴跟任何其他恒河猴接触。结果发现,无论是部分隔离还是完全隔离的幼猴,在社交能力、情绪方面均有显著改变。禁闭6个月以上的小恒河猴表现出严重的情绪不安、害怕、退缩。这是一个悲观的结果。     

铅对恒河猴的月经和妊娠结局影响的观察

本文报道了恒河猴在接触较低剂量醋酸铅的亚慢性作用下,对月经和妊娠结局的影响。结果表明,铅可引起恒河猴的月经机能障碍、受孕率降低和流产。月经异常以周期延长和周期不规则为主,周期不规则发生率呈剂量-反应关系。     

哪些病易导致白内障

糖尿病 糖尿病是一个非常复杂的代谢性疾病,血糖高,引起晶状体内糖及其代谢产物糖醇、山梨醇的积聚,晶状体渗透压增高,导致晶状体吸水、肿胀、混浊。 肾功能衰竭 肾功能衰竭可导致血液中尿素含量增加,由此产生全身性渗透压改变,晶状     

低剂量铅间断性染毒对恒河猴慢性毒性和自然恢复的影响

本文以较低剂量(5和20mg/kg)的醋酸铅对恒河猴进行重复二次染毒,实验结果表明,动物中毒表现不明显,但铅特异指标如PbB、FEP、ZnPP和δ-ALAD等含量已发生明显的改变。血清钙含量在染毒前、后无显著差异。两次染毒猴子对铅的吸收速率基本一致,第二阶段染毒停止后PbB水平恢复要慢于第一阶段,提示铅蓄积随染毒时间、频率而增加。在本实验剂量下,主要引起机体铅蓄积和铅接触指标的变化。此外,由于长期接触尚可能造成部分脏器的功能异常。     

95%氟蚁腙原药急性迟发性神经毒性试验

目的了解95%氟蚁腙原药迟发性神经毒性。方法成年母鸡60只,随机分成5组(174 mg/kg BW、435 mg/kg BW、1 740mg/kg BW、阴性对照组及阳性对照组)。染毒后持续观察21d,21d后重复染毒,试验期间观察对动物一般表现、体重、共济失调、血液生化、病理组织学检查等指标进行观察及检测。结果试验组未见明显共济失调等迟发性神经毒性反应;阳性对照组出现明显迟发性神经毒性改变;阴性对照组各指标均未见明显异常。结论 95%氟蚁腙原药未引起迟发性神经毒性反应。     

茶多酚对D-半乳糖诱致大鼠眼晶状体损伤的干预作用及其机制

目的探讨茶多酚对D-半乳糖诱致大鼠眼晶体损伤的干预作用及其机制。方法D-半乳糖(400mg/kg bw)腹腔注射给药,2w后模型大鼠同时给予氨基胍(75mg/kg bw)和茶多酚高、中、低(150、75、37.5mg/kg bw)剂量处理至第14w。处理动物并取血测定红细胞醛糖还原酶(AR)活性、糖化血红蛋白、血清果糖胺(FRA)和晚期血浆糖基化终末产物(AGEs)含量;取眼晶状体测定AR、GR、SOD和SDH活性,测定AGEs、GSH、MDA含量和乳酸脱氢酶(LDH)漏出量,流式细胞术检测晶状体上皮细胞凋亡情况,透射电镜观察晶状体上皮细胞超微结构的变化。结果D-半乳糖处理动物14w后,体内糖化血红蛋白、血清果糖胺、AGEs水平和AR活性明显升高,并伴有眼晶状体AGEs含量和AR活性的增加,抗氧化酶活性降低,氧化产物增加,晶状体上皮细胞出现凋亡及细胞核和线粒体结构的损伤。茶多酚处理12w后,明显降低动物体内红细胞和晶体AR活性,降低糖化血红蛋白、血清果糖胺和AGEs含量,降低晶状体AGEs、MDA含量和LDH释放量,提高GR、SDH和SOD活性,并降低晶状体上皮细胞凋亡率,减少细胞核和线粒体结构损伤的程度。结论D-半乳糖可诱致大鼠全身和眼晶状体糖基化和氧化应激性损伤,导致眼晶体细胞核和线粒体结构改变,诱导细胞凋亡,茶多酚可能通过抑制糖基化和氧化应激反应,对其损伤提供保护作用。     

Protective Effect of Polysaccharides Isolated from <i>Tremella fuciformis</i> against Radiation-induced Damage in Mice

WTF-B, a type of water-soluble homogeneous polysaccharide, was isolated and purified from Tremella Fuciformis. To investigate the radioprotective effect of WTF-B, we employed a 30-day survival assay. Mice were treated with WTF-B once per day for three consecutive days before 8-Gy gamma irradiation. The treatment groups receiving 54 and 72 mg/kg body weight (b.w.) of WTF-B showed 50% survival post-irradiation. The hematological parameters of the peripheral blood indicated that WTF-B, when administered at doses of 72 mg/kg b.w., significantly restored hemoglobin, white blood cell counts and red blood cell counts by the 14th day and 18th day. In addition, spleen colony forming units (CFU-S), the number of nucleated cells in bone marrow (BMNC) and spleen index were used to investigate the radioprotective effect of WTF-B on the hematopoietic system. The treatment groups receiving WTF-B at 18, 54 and 72 mg/kg b.w. doses presented significantly higher BMNC compared to radiation-only group. The group administered 72 mg/kg b.w. WTF-B presented a significant change in CFU-S compared to the radiation-only group. We also completed micronucleus and chromosome aberration assays to explore genotoxicity. The results of those assays indicated that the number of micronuclei induced by 2-Gy irradiation in a group treated with 72 mg/kg b.w. WTF-B decreased from 30.30‰ to 11.32‰. The chromosomal aberration produced by 3-Gy irradiation in the group receiving 72 mg/kg b.w. WTF-B decreased from 56.01% to 28.13%. The results of the present study indicate a potential use for WTF-B as a radioprotector.     

Toxicologic evaluation of diisopropyl methylphosphonate and dicyclopentadiene in cattle

Diisopropyl methylphosphonate (DIMP), and dicyclopentadiene [3a,4,7,7a-tetrahydro-4,7-methyanoindene] (DCPD), were found as contaminants of groundwater in Colorado. Since there was a potential for cattle to be exposed to these chemicals by drinking well water, a study of their effects was initiated. Eight-to-ten week old calves were given a single dose of either DIMP at 62.5, 125, 250, 500 and 1000 mg/kg of body weight (b.w.) or DCPD at 250, 500, 1000 or 2000 mg/kg of b.w. The calves given DIMP developed tympanitis and ataxia, followed by depression, prostration, and death within two hr after dosing. A slight but significant increase in activated partial thromboplastin time was the only change observed in any of the clinical pathologic parameters. The only gross pathologic changes were acute gastroenteritis with hemorrhages in calves given 1000 mg/kg of b.w. Mild signs of intoxication, ataxia and excess salivation, were observed in calves given 250 mg of DCPD/kg of b.w. At higher doses, these signs were intensified; in addition, calves fell and, while prostrate, exhibited running movements and tonic, clonic spasms. The severity of the signs observed increased as the dose of DCPD increased. All calves given 2000 mg/kg of b.w. and one calf given 1000 mg/kg of b.w. died before seven days after dosing. The only clinical pathologic changes found were increased serum levels of creatine phosphokinase, glutamic-oxalacetic transaminase, and glutamic pyruvic transaminase. The only consistent gross pathologic change was congestion in a variety of tissues in calves given 2000 mg/kg of b.w. A variety of histologic changes were observed in tissues from calves treated with both chemicals. However, these changes were not consistent for any one dose level and were not dose dependent. DIMP was slightly toxic for calves, since no signs of intoxication were observed at doses less than 1000 mg/kg of b.w. DCPD exerted detrimental effects on calves at 250 mg/kg of b.w. and was classified as moderately toxic.This study was supported by the U.S. Army Medical Research and Development Command, Fort Detrick, MD.Deceased.     

外源性谷胱甘肽对饮水砷暴露雌性小鼠脑砷形态及一氧化氮代谢的影响

目的 探讨外源性谷胱甘肽(glutathione,GSH)对饮水砷暴露小鼠脑中砷形态分布及一氧化氮(nitric oxide,NO)代谢的影响.方法 将40只雌性昆明小鼠随机分为对照组、单独染砷(NaAsO_2)组及低剂量(200mg/kg)、中剂量(400mg/kg)或高剂量(800mg/kg)GSH干预组,每组8只.染毒组小鼠饮水染砷4周,在最后一周,在染砷同时腹腔注射不同剂量GSH.末次注射后24h处死小鼠,取血和脑组织,分别检测无机砷(iAs)、一甲基胂酸(MMA)和二甲基胂酸(DMA)含量及脑中一氧化氮合酶(NOS)活力和NO含量.结果 GSH干预组小鼠血中iAs、MMA和总砷(TAs)含量及脑中DMA和TAs含量与单独染砷组比较显著下降.与对照组相比,单独染砷组小鼠脑中NOS活力及NO含量显著降低.与单独染砷组比较,中、高剂量GSH干预组小鼠脑中NOS活力显著升高.结论 给予外源性GSH可减少血液和脑组织中的砷负荷,进而改善砷对脑内NO代谢的影响.     

Total antioxidant status in the blood serum of rats exposed to N-nitroso compounds and nitric oxide synthase inhibitors

In this study, the total antioxidant status (TAS) was assayed in the blood serum of rats pretreated per os with either N-nitrosodiethylamine (NDEA) (0.1 mg/kg b.w./day) or N-methyl-N-nitrosourea (NMU) (0.1 mg/kg b.w./day) for 30 days. The animals were also dosed per os with spermidine (SPR) (10 mg/kg b.w./day) for a first 21 day period, and Nomega)-nitro-L-arginine methyl ester (L-NAME) (10 mg/kg b.w./day) given to animals for 3 days (days 22-24), respectively. Nitric oxide synthase (NOS) inhibitor, L-NAME was found to mitigate TAS levels in the blood serum of rats pretreated with NDEA and NMU. No such changes were found in animals dosed with L-NAME only nor even with L-NAME and spermidine, respectively. Since spermidine, also known as an inhibitor of iNOS synthesis, elevated TAS levels in rats dosed with L-NAME and NDEA/NMU, the polyamine was suggested to modify the NOS/NO origin to serve the physiological level of the total anti-oxidant status in rat blood serum.     

Effects of cyproterone acetate with combination of testosterone enanthate on seminal characteristics, androgenicity and clinical chemistry in langur monkey

Daily oral administration of 1 mg/kg b.w. of cyproterone acetate and simultaneously administered testosterone enanthate (2 mg/kg b.w./15 days; i.m.) to adult male langur monkeys over a period of 90 days caused a gradual decrease in the count (to azoospermia) and motility of spermatozoa, concurrently with an increase in the percentage of non-motile as well as abnormal and immature sperm. Semen weight, volume, seminal fluid volume and circulating testosterone levels decreased nonsignificantly. Semen pH, libido and body weight remained unimpaired. The levels of SGOT, SGPT, serum alkaline phosphatase, LDH, bilirubin, Na⁺, K⁺ and hematological values did not alter significantly. All the changes were reversible. The results indicate that the combination regimen seems to affect the fertility in two ways, i.e. by inhibiting spermatogenesis in the testis and maturation process in the epididymis without altering the androgenicity.     

Biochemical Responses and Accumulation Properties of Long-Chain Perfluorinated Compounds (PFOS/PFDA/PFOA) in Juvenile Chickens (<Emphasis Type="Italic">Gallus gallus</Emphasis>)

One-day-old male chickens were exposed via oral gavage to mixtures of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorodecanoate (PFDA) at either a low dose (0.1 mg/kg body weight [b.w.]) or a high dose (1.0 mg/kg b.w.), or a saline/ethanol vehicle control, three times a week for 3 weeks. After 3 weeks of exposure, half of the chicks were sacrificed and the other half were allowed to depurate for a further 3 weeks. No dose-dependent statistically significant differences in body/organ weights were observed among treatment and control groups after 3 weeks of exposure or after three 3 of depuration. Neither 15 histological nor 14 measured plasma biochemical parameters were significantly different in chicks from the exposed groups and vehicle controls. PFOS, PFDA, and PFOA concentrations in blood/liver/kidney samples were measured throughout the exposure and depuration periods at different time intervals. PFOS and PFDA accumulated at much higher concentrations than PFOA during the experimental periods. Interestingly, PFOS and PFDA accumulation patterns in the blood were similar during the exposure and depuration periods. The half-lives for each PFC at the 0.1 and 1.0 mg/kg doses were, respectively, approximately 15 and 17 days for PFOS, 11 and 16 days for PFDA, and 3.9 and 3.9 days for PFOA. PFDA accumulation in organs was greater than or similar to that of PFOS: the liver was the main target during exposure and the blood was the main reservoir during depuration. These results indicate that exposure to a 1.0-mg mixture of PFOS/PFDA/PFOA/kg b.w. has no adverse effect on juvenile chickens.     

Metabolism of the schistosomicidal agent hycanthone by rats and rhesus monkeys

The absorption, distribution, and excretion of hycanthone were studied with rats and rhesus monkeys using tritiated materials at the therapeutic dose recommended for man (3.0±0.5 mg/kg). Nine pairs of each species received single intramuscular doses of randomly tritiated (specific activity 193.7 mCi/mmol) hycanthone methanesulfonate and were then sacrificed at intervals between 15 min and 72 h after medication. Peak blood and tissue concentrations occurred 30-60 min after administration (plasma half-life—45 min). The highest concentrations were observed in the liver, spleen, kidneys and adrenals, but decreased rapidly (more than 80% of the dose was excreted in 48-72 hours). In monkeys a high concentration of the compound was found in the bile (hours 1-8), probably conjugated to glucuronic acid.     

银耳多糖辐射防护作用的研究

目的 研究银耳多糖对辐射损伤小鼠的保护作用。方法 采用小鼠30天存活率和外周血液学参数考察银耳多糖对辐射损伤小鼠的保护作用。结果 小鼠在接受8Gy伽玛射线照射前连续三天以18,54,72 mg/kg剂量腹腔注射银耳多糖,可以明显减轻照射对小鼠造成的损伤,使存活率增强,存活天数延长。外周血中血红蛋白含量、白细胞数、红细胞数在照射后第14,18天保持较高水平,与单纯照射组相比有统计学意义(P < 0.05)。结论 银耳多糖对辐射损伤小鼠有较好的保护作用。     

白内障与血液及眼球组织中锌关系的实验研究

目的 :探讨白内障与血液及眼球组织中锌含量的关系。方法 :用亚硒酸复制 SD大鼠白内障模型 ,给预防组大鼠眼内补锌 4周后 ,观察各组大鼠晶体的变化并测定其血液和眼球组织中的锌含量。结果 :模型组及预防组大鼠血液中的锌含量均明显低于正常对照组 ,其差异具有显著性 ( P<0 .0 1和 P<0 .0 5 ) ;预防组大鼠眼球组织中的锌含量明显高于正常对照组 ,其差异具有非常显著性 ( P<0 .0 1 )。眼内补锌的预防组大鼠晶体混浊程度较模型组的轻。结论 :白内障大鼠血液中的锌含量降低 ,而眼球组织中的锌含量升高 ;锌对硒性白内障的发生和发展具有抑制和延缓作用