慢性病毒性肝炎2′-5′寡腺苷酸合成酶活性研究

ＰＰＰＡ２Ｐ５Ａ２Ｐ５Ａ寡腺苷酸（简称２′－５′Ｐ３Ａ３）是干扰素作用细胞后诱生的２′－５′Ｐ３Ａ３合成酶利用ＡＴＰ为原料合成的物质〔１〕。它具有广泛的生物学活性如抗病毒〔２〕、抗肿瘤、免疫调节及大分子生物合成抑制作用〔３〕。本文选择慢性乙肝病人７４...     

固相时间分辨荧光免疫分析螯合剂(Ⅰ)中间体—4,4′-二溴-6,6′-二甲基2,2′-联吡啶的合成

目的:合成固相时间分辨荧光免疫分析螯合剂的中间体-4,4′-二溴-6,6′二甲基2,2′-二吡啶。方法:根据自行设计的合成路线,以2-氨基6-甲基吡啶为原料,经重氮化、乌尔曼偶联合成6,6′-二甲基-2,2′-二吡啶,再经氧化、硝化、溴化、脱氧等合成4,4′-二溴-6,6′二甲基2,2′-二吡啶。结果:经元素分析、红外光谱,核磁共振波谱等方法证明:成功的合成了4,4′-二溴-6,6′二甲基2,2′-二吡啶。结论:通过自行设计路线完成了4,4′-二溴-6,6′二甲基2,2′-二吡啶的合成,为固相时间分辨荧光免疫分析的应用提供了有价值的中间体和制备方法。     

p,p′-DDT andp,p′-DDE effects on egg production,eggshell thickness,and reproduction of japanese quail

Summary p,p-DDT and p,p-DDE were investigated for effects on egg production and eggshell thickness in Japanese quail. p,p-DDT was examined for effects on hatchability and fertility. DDE was tested at 0, 2, 10, 40, and 200 ppm in the diet. No evidence suggested that DDE affected number of eggs laid, egg weight, or eggshell thickness at any level of DDE tested. DDT was tested at 1, 2.5, 10, and 40 ppm in the diet. In one experiment, quail fed DDT at 40 ppm and caged in male-female pairs broke more eggs than quail caged similarly but fed lower amounts of DDT or than quail fed an equal amount of DDT but caged alone. DDT did not detectably reduce eggshell thickness, number of eggs laid, fertility, or hatchability. However, paired quail laid fewer eggs than did single quail in two experiments and laid eggs with thinner shells in one experiment.     

Vergiftungserscheinungen bei dicyclohexyl-methan-4-4′-diisocyanat-exposition

Zusammenfassung Vergiftungen durch organische Isocyanate (OI) sind schon seit dem Zweiten Weltkrieg bekannt.Die bekanntesten OI sind Toluylen-Diisocyanat (TDI), Diphenyl-Methan-Diisocyanat (MDI), Naphtylen-Diisocyanat (NDI) and Hexamethylen-Diisocyanat (HDI). Alle oben erwdhnten organischen Isocyanate werden für verschiedenartige Zwecke zu Polyurethane polymerisiert.Das Dicyclohexyl-Methane-4-4-Diisocyanate (DMDI) wird zur Zeit für Flaschenüberzüge in Japan and Israel benötigt, um so evtl. Verletzungen durch Glasscherben zu verhindern.Elf von 15 Arbeitnehmern, die zuerst DMDI exponiert waren, zeigten vier bis sieben Tage nach Beginn der Exposition verschiedenartige Hautaffektionen im Bereich der unbedeckten Körperteile. Sechs litten an Vertigo mit oder ohne Kopfschmerzen und vier zeigten obstruktive Ventilationsstörungen, Tachykardie und Hypotension (EKG-Normal-Befund). Alle werden oral mit Antihistaminica und lokal mit Steroiden mit gutem Erfolg behandelt. Es konnten keine Unterschiede zwischen den Arbeitern der atopischen und der nicht-atopischen Gruppe festgestellt werden. Alle Zeichen der Vergiftung verschwanden nach 10 bis 14tägiger Behandlung. DMDI scheint nicht die Atemwege so stark anzugreifen wie TDI. Mögliche chronische Schädigungen werden diskutiert. Die Schwierigkeiten, DMDI in der Luft zu messen, werden festgestellt (MAK = 0,003 ppm).     

肌肤的20′30′40′

肌肤保养之道千变万化。但是总离不开“阻止衰老”这个经久不衰的课题。以往只有稍大的女士才注重抗衰老的保养。但时到今日，护肤概念已经演化成为延长肌肤青春状态。而且愈早开始行动愈好。     

Levels of β-HCH,HCB, p,p′-DDE,p,p′-DDT and PCBs in human milk from a continental town in Croatia,Yugoslavia

Summary Concentrations of -HCH, HCB, p,p-DDE, p,p-DDT and PCBs were determined by gas chromatography in 50 human milk samples collected from the general population during 1981/1982 in a continental town in Croatia (Yugoslavia). The samples were collected between one and 22 weeks after delivery from mothers breast-feeding one child only. The mothers' age was 18 to 31 years, and they were nursing their first or second child. All 50 samples contained -HCH, HCB, p,p-DDE and PCBs, whereas p,p-DDT was present in 37 samples. The concentrations of -HCH, HCB, p,p-DDE, p,p-DDT and PCBs expressed on a whole milk basis were (median in g/kg): 11, 7.1, 67, 7.3 and 22 respectively, and expressed on a fat basis (median in mg/kg): 0.28, 0.21, 1.9, 0.18 and 0.62 respectively. The fat content was 3.7% (median). PCBs were present in a mixture containing penta-, hexa- and heptachlorobiphenyls.     

Polychlorobiphenyl congeners,p,p′-DDE,and sperm function in humans

170 seminal samples from fertile men, men with idiopathic oligospermia or azoospermia and men status post vasectomy were analyzed for 74 polychlorobiphenyl (PCB) congeners,p,p-DDE, mirex, and hexachlorobenzene using the technique of glass capillary gas chromatography with electron capture detection. Low concentrations of 32 PCB congeners were measured (mean total PCB residue of 5.8 ng/g wet weight). The application of multiple linear regression analysis to the data is described and the result is critically evaluated. There is a correlation between sperm motility and count. There are indications that the concentrations of three PCB congeners (2,4,5,245- and 2,4,5,234-hexachlorobiphenyl and 2,4,5,34-pentachlorobiphenyl) are inversely correlated with sperm motility index in samples with a sperm count less than 20 million cells/ml. The implications of the discerned associations are discussed.     

大米粉中α-666和O,P′-DDT农药残留测定能力验证

目的验证中心实验室对大米粉中α-666和O,P′-DDT农药残留检测结果的准确性,促进实验室检测能力提高。方法依据能力验证作业指导书和GB/T 5009.146—2008方法,对大米粉样品的前处理、标准曲线的制备等进行了优化,提取液经HP-5色谱柱分离,气相色谱-ECD检测器测定,外标法定量。结果优化对大米粉样品的前处理、标准曲线的制备,实验室检测结果与能力验证组织单位的结果一致,通过能力验证考核。结论通过参加能力验证可提高实验室对该项目日常检测结果可靠性,强化实验室质量管理工作。     

Short-Term Distribution, Metabolism, and Excretion of 2,2′,5-Tri-, 2,2′,4,4′-Tetra-, and 3,3′,4,4′-Tetrachlorobiphenyls in Prepubertal Rats

The excretion and tissue retention of three ¹⁴C-labeled lower chlorinated biphenyls were examined in prepubertal male and female Sprague-Dawley rats following IV administration. Urine and feces were collected individually at different time intervals up to 72 h for pharmacokinetic analyses. After 72 h, different organs were removed and extracted in acetone:hexane (1:1, v/v) to determine radioactivity. Within the first 10 h after dosing, 2,2′,5-trichlorobiphenyl (PCB 18) was rapidly excreted in urine (8–18% of the administered dose), whereas only 0.6–0.8% of 2,2′,4,4′-tetrachlorobiphenyl (PCB 47) and 0.3–0.8% 3,3′,4,4′-tetrachlorobiphenyl (PCB 77) were found in urine during this time period. The half-life of elimination was shortest for PCB 18 (37.5 to 49.2 h). The half-lives for PCB 47 and PCB 77 were 351 to 672 h and 152 to 186 h, respectively. The cumulative total excretion (urinary + fecal) of PCB 18 within 72 h was 51–62%, of PCB 77 was 22–25%, and of PCB 47 was 7–10%. No parent PCBs were detected in urine. PCB 47 accumulated preferentially in adipose tissues (subcutaneous fat > mesenteric fat); relatively high levels of PCB 47 were also found in adrenals, ovaries, lungs, liver, and skin. The highest concentration of PCB 77 was found in serum, followed by adipose tissues. Very low concentrations of PCB 18 were found in most tissues; the highest being found in serum, followed by ovaries and adrenal glands. This study suggests that prepubertal rats retain higher short-term serum levels and have lower excretion rates than adult rats. Received: 3 February 1998/Accepted: 16 August 1998     

肿瘤病人血清5′-核苷酸酶活性测定比较

血清５′－核苷酸酶（５′－Ｎｕ）能催化５′－Ｎｕ磷酸水解酶，在人体内此酶主要存在于肝内毛细血管和血窦侧的肝细胞膜中。肝癌患者肝细胞内质网的膜结构破坏明显，线粒体发生退行性改变甚至消失，合成机制发生障碍，还有丰富的血窦形成，Ｄｉｓ氏间隙被胶原纤维所充填...     

关于3,3′-二氯联苯胺的毒性和致癌性

3,3′-二氯联苯胺(3,3′-Dichlorobenzidine,以下简称DCB,是一种生产染料和颜料的重要中间体,特别在合成各种黄色颜料、橙色颜料和红色颜料方面,它是不可代替的极为重要的中间体,它与联苯胺、3,3′-二甲基联苯胺、3,3′-二甲氧基联苯胺反应可得到424种颜料和染料产品,是油漆、油墨、橡胶、塑料等产品的着色剂,成为印刷、油墨、涂料、橡胶、塑料等工业中不可缺少的制品。它的应用已有六十多年的历史。由于它的结构和已知致癌物联苯胺相似,人们怀疑它可能是人的致     

Comparative toxicokinetics of 2,2′- and 4,4′-dichlorobiphenyls in the pond snailLymnaea stagnalis (L.)

Pond snails (Lymnaea stagnalis (L.)) were treated with 2,2-dichlorobiphenyl (DCB) or 4,4-DCB, to examine the toxicokinetic profile of these compounds. Snails were treated orally with 210 g 4,4-DCB (impregnated on food) for 14 hr, or snails were injected with 50 g of 2,2-DCB or 4,4-DCB in the foot. At different times after starting feeding or injection, tissues (albumen gland, digestive gland and digestive tube, central nervous system, remainder parts), hemolymph and faeces were analyzed for unchanged 2,2- or 4,4-DCB. The results showed that in case of oral administration of 4,4-DCB after 144 hr, 97.5% of the dose was excreted unchanged in the faeces. During the first 48 hr 4,4-DCB was found in all tissues. Thereafter, an exponential elimination was found (the rate constant of elimination (k_el) varied from 0.010–0.021 per hr, t_1/2 from 33–60 hr and the apparent clearance from 0.02–0.3 g/hr for the different tissues). After injection, the compounds were found in all the above mentioned tissues, especially in the digestive gland. There was a clear difference between snails injected with 2,2- and 4,4-DCB. Firstly, k_el for 2,2-DCB was higher (0.028 per hr vs 4,4-DCB: 0.001 per hr). Secondly, 2,2-DCB was lethal; 63% of the animals died after 72 hr.     

3，3′，5，5′-四甲基联苯胺现场测定游离余氯的质控

用3，3′，5，5′-四甲基联苯胺替代邻联甲苯胺测定游离余氯，测定控制的条件也发生了一些变化。如何在现场测定时控制这些条件，既方便又能保证测定结果的准确性，是我们进行这次比对实验的目的。本实验按照《生活饮用水卫生规范》(下称规范)、GB5750—85《生活饮用水卫生标准检验方法》(下称标准)的要求，对两种方法进行比     

半抗原:N-甲基-N′-戊酸基-二吡啶-二溴化物的合成

为了建立除草剂—百草枯的酶联免疫吸附测定 (ELISA)方法 ,由 4 ,4′ 二吡啶为原料 ,经过两步季氨化反应 ,而后水解 ,合成了半抗原 :N 甲基 N′ 戊酸基 二吡啶 二溴化物 ( 1)产物结构经核磁共振氢谱确认     

Distribution of CCR5-Δ32, CCR5m303A,CCR2-64I and SDF1-3′A in HIV-1 infected and uninfected high-risk Uighurs in Xinjiang,China

BackgroundGenetic variants of the genes encoding HIV-1 co-receptors and their ligands, CCR5-Δ32, CCR5m303A, CCR2-64I and SDF1-3′A, are implicated in the susceptibility to HIV-1 infection, and the prevalence of these mutations varies by ethnicity. However, little is known about their distribution in Uighurs.ObjectivesThis study aimed at characterizing the frequency of these HIV-related gene variants in a high-risk Uighur population.Study designsA total of 251 HIV-1 seropositive and 238 seronegative high-risk Uighurs were recruited and their genotypes of CCR5-Δ32, CCR5m303A, CCR2-64I and SDF1-3′A were analyzed by PCR and PCR-ligase detection reaction (PCR-LDR).ResultsThe allelic frequency of CCR5-Δ32, CCR5m303A, CCR2-64I and SDF1-3′A was 4.40%, 2.66%, 25.66% and 57.36%, respectively, in this population. Apparently, the Uighur population has low frequency of CCR5-Δ32 and CCR5m303A, but high frequency of CCR2-64I and SDF1-3′A. While there was no significant difference in the frequency of CCR5-Δ32, CCR2-64I and SDF1-3′ A between HIV-1 seropositive and seronegative groups the frequency of CCR5m303A in HIV-1 seropositive group was significantly higher than that in seronegative group (P = 0.006, OR = 3.982 and 95%CI 1.514–10.476).ConclusionsOur data suggest that the CCR5-Δ32, CCR2-64I and SDF1-3′A variants may have limited effect on protecting from HIV-1 infection in Uighurs. Rather, the CCR5m303A may be associated with the risk for HIV-1 infection in high-risk Uighurs.     

Chronic effects of 2,2′-dichlorobiphenyl on reproduction,mortality, growth,and respiration ofDaphnia pulicaria

Previous studies have shown toxic effects of polychlorinated biphenyls (PCBs) on aquatic life only in the g/L range, well above normal ambient concentrations.Daphnia pulicaria was isolated from Lake Erie and exposed to 50 ng/L to 10 g/L of 2,2-dichlorobiphenyl (DCB) in lifetable and physiological studies. Reproduction, mortality, growth, and respiration were measured for periods up to the entire lifespan of the animal with and without the use of an organic surfactant. One experiment was conducted for three generations of the daphnid continuously exposed to DCB.Significant mortality and inhibition of reproduction were found at levels as low as 50–100 ng/L in lifetable studies, and no safe level could be determined. These are among the lowest levels ever reported for a PCB congener to cause significant biological effects. A unique, yet repeatable, dose-re-sponse curve occurred in lifetables with maximum inhibition at low to intermediate concentrations. Inhibition at the highest level tested, 10 g/L, occurred only after continuous exposure for three generations. Increasing concentrations of DCB stimulated growth, while respiration experiments yielded variable results.     

Maternal transfer of14C-p,p′- DDTvia Placenta and milk and its metabolism in infant rats

Female rats were dosed orally with 0.9 mg¹⁴C-ring-labeledp,p-DDT during pregnancy or lactation. The results from the lactation experiment showed that the mean concentration of¹⁴C-DDT in milk was 15.26g per g dry weight the first day after dosing, and decreased gradually with a rate constant of clearance of –0.096. The half-life of DDT and its metabolites in milk was approximately 7.2 days. Neonatal rats, sacrificed after 1 to 28 days, showed that the maximal concentration of¹⁴C was generally reached in 1 to 3 days then declined at a rate comparable to that in milk. Liver, intestine, and carcass had the highest radioactivity; next, in decreasing order, were lung, kidney, heart, brain, and blood. In the liver of the neonate, the relative concentration of DDT was decreased from 100% in the first day to 44% in the 28th day, while DDD and DDE increased gradually to 36% and 22%, respectively. In the experiment with pregnant rats, the results showed that DDT was readily absorbed, transported throughout the whole body, and deposited in the fetuses. The average biological halflife of DDT in various tissues and the fetus was 10.6 hr. DDT was converted more rapidly to DDD, DDE, and two minor unidentified metabolites in the adult liver than in the liver of neonates. DDE and DDD were also found in other tissues and fetuses of pregnant rats. The relative amounts of DDE and DDD varied in different tissues. DDA was not present in all tissues examined. In the placenta and fetuses, it was only detectable, whereas in the lung, intestine, blood, and kidney, it was a major metabolite.Technical paper no. 4208 Oregon Agricultural Experiment Station, Corvalis, Oregon. This investigation was supported in part by NIEHS Grants No. ES00210 and ES00040 11.     

高效液相色谱法测定尿中的N′-烷基烟酰胺

N′-烷基烟酰胺是烟酸和烟酰胺在尿中的主要代谢产物,影响细胞内吡啶核苷酸的调节,其在尿中的含量与各种疾病状态有一定联系。本文报道了用高效液相色谱法测定尿中N′-烷基烟酰胺类(C_1～C_5烷基衍生物)的方法。仪器:用LC-2型色谱仪、填充剂为Zor-bax SCX-300(7～8 μm,Du Pont)的柱(15×0.46 cm.i.d)和     

Eggshell thinning in ring doves exposed top,p′-dicofol

Ring doves (Streptopelia risoria) were brought into breeding condition and, after laying two clutches of two eggs each, were fed one of three experimental diets containing either 33.4 ppm dicofol (1, 1-bis(p-chlorophenyl)-2,2,2-trichioroethanol), 37 ppmp,pi DDE (2,2-bis (p-chlorophenyl)-1,1 dichloroethylene), or no toxicant (control). Mean shell thicknesses of eggs produced on experimental diets were: control, 156 x; DDE, 145 ; and dicofol 142 . Birds fed DDE produced eggs with shells a mean 5.6% thinner than pre-treatment eggs, while birds fed dicofol produced eggs with shell means 7.2% thinner. No change in shell thickness was found in eggs from control doves. Analysis of covariance revealed a statistically significant effect of decreasing eggshell thickness over time in doves fed DDE and dicofol diets but not in control birds. Egg production was significantly lower in both dicofol-fed and DDE-fed birds when compared with controls. Control birds produced a mean of 1.97 eggs per clutch. Dicofol- and DDE-treated birds produced 1.88 and 1.79 eggs per clutch, respectively. The proportion of eggs found cracked or broken in the nest was greatest in birds fed dicofol, with 16.9% of all eggs broken or cracked, compared to 7.9% of eggs from the DDE group and 5.7% of eggs from control group. Selected eggs were analyzed for residues of dicofol, dichlorobenzophenone (DCBP), and DDE in the yolk. For the birds fed the dicofol diet, DDE residues in treatment eggs ranged from 0.036 to 0.119 ppm wet weight. DDE residues in pre-treatment eggs ranged from 0.013 to 0.080 ppm. Dicofol residues ranged from 2.62 ppm to 22.58 ppm. DCBP residues ranged from 2.55 to 17.68 ppm. Only residues of dicofol showed a significant correlation with percent shell thinning.