荧光探针在大鼠胃粘膜表面疏水性研究中的应用

采用１－萘胺－８－磺酸（ＡＮＳ）为疏水探针,对大鼠胃粘膜表面疏水性作了研究,结果表明：以ＡＮＳ（２５μｍｏｌ／Ｌ）与胃粘膜表面刮取物（胃粘液凝胶层）混合后的萤光强度（正常为１．２３±０．１９ＲＦＵ／胃）可代表该粘液层的疏水性;以不同浓度ＡＮＳ与胃粘液混合后的萤光强度呈饱和趋势,可用Ｓｃａｔｃｈａｒｄ作图法求得粘液中ＡＮＳ的最大萤光强度（２．４６７±０．６３８ＲＦＵ／胃）和相对亲和系数（０．０３２±０．０１６）,它们可分别代表胃粘液中疏水基团的总量和单个基团的疏水性,从而可阐明胃粘膜被盐酸损伤后凝胶层粘液的ＡＮＳ萤光减弱,系其疏水基团总量减少,而非单个基团的疏水性改变所致。     

西藏林芝真蚋亚属三新种（双翅目：蚋科）

本文记述西藏林芝真蚋亚属Ｅｕｓｉｍｕｌｉｕｍ三种：凸端真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｃｏｎｃａｖｕｓｔｙｌｕｍｓｐ．ｎｏｖ．、林芝真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｌｉｎｇｚｉｅｎｓｅｓｐ．ｎｏｖ．、裂缘真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｓｃｈｉｚｏｌｏｍｕｎｓｐ．ｎｏｖ 。     

模拟失重对大鼠心肌力学与生物化学的影响

观察为期４周模拟失重对大鼠心肌收缩性能与收缩蛋白性质的影响,发现模拟失重大鼠左心室乳头肌等长收缩的力学特征发生下列变化：发展张力峰值降低２９％（Ｐ〈０．０１）;达到张力峰值的时间延长１０％（Ｐ〈０．０５）;舒张一半的时间缩短１１％,但未达到显著水平（Ｐ〉０．０５）。心肌力学参数的这些变化表明模拟失重使大鼠心肌收缩性能降低。进一步研究显示,模拟失重大鼠左室心肌肌原纤维Ｃａ＾２＋,Ｍｇ＾２＋－ＡＴＰ酶     

Preference of a revolving target to a stationary one by the big brown bat, Eptesicus fuscus

Utilizing a three-ramp platform, we studied the detection of a revolving and a stationary target in the presence of background clutter by trained Eptesicus fuscus. During the test, the mean amplitude of echo from either target was always larger than that of the background echoes at the bat-to-target distance of 30, 70 and 100 cm. The amplitude of the echo reflected back from a revolving target was modulated between a maximum and a minimum value. An electric motor was used to revolve a target. The frequency contents of the motor noise were mostly below 1 kHz. While the total percent response of approaching either target is always more than 90% at every bat-to-target distance tested, the bats approach a revolving target more frequently than a stationary one. Echolocation pulses emitted by the bats during the test were recorded and analyzed. The bats shortened their pulse durations and interpulse intervals and lowered the frequency contents as they entered into the crawling phase from the searching phase. Potential interference of background echoes and ambient noise with the performance of the bats is discussed. The preference of a revolving target to a stationary one by the bats is perhaps due to the fact that a revolving target has a higher releasing value than a stationary one does.     

Production and characterization of antibody against aflatoxin Q1.

Antibodies against aflatoxin Q1 (AFQ1) were obtained from rabbits after immunization of either AFQ1-hemisuccinate or AFQ2a conjugated to bovine serum albumin. Both radioimmunoassay and enzyme-linked immunosorbent assaY (ELISA) were used for the determination of antibody titers and specificities. Antibodies obtained from rabbits after immunization with AFQ1-hemisuccinate-bovine serum albumin had the highest affinity to aflatoxin B1, whereas antibodies obtained from rabbits after immunization with AFQ2a-bovine serum albumin bound most effectively with AFQ2a. AFQ2a antibody was selected for the subsequent direct and indirect ELISA for the detection of AFQ1 in biological fluids. When AFQ2a-peroxidase and AFQ2a antibody were used, direct ELISA was able to detect as low as 2 ppb (ng/ml) of AFQ1 spiked in the urine samples that had been subjected to a Sep-Pak cleanup treatment. In indirect ELISA in which the antigen (AFQ2a-bovine serum albumin) was coated to the solid phase followed by reaction with rabbit antibody and goat anti-rabbit immunoglobulin G-peroxidase conjugate, 50-fold less antibody was used without sacrificing sensitivity. Recoveries of AFQ1 added to urine samples (2 to 40 ppb) were 46.3 to 73% and 65.8 to 85.8% for direct and indirect ELISA, respectively.     

PI LBEI and PI JHOU: two new alpha-1-antitrypsin alleles

Summary Two new variants of alpha-1-antitrypsin were found in a Chinese population by isoelectric focusing in polyacrylamide gel. They have been named Lbeijing (PI^*LBEI) and Jhouyao (PI^*JHOU) respectively. With the samples reduced and alkylated, both the variants were anodal to M1 and cathodal to L. Omitting the alkylation step, however, the relative mobilities of L and Jhouyao were altered. Under this condition, a characteristic of Jhouyao was revealed by isoelectric focusing in immobilized pH gradient 4.4–4.9, i.e., while its band 6 became anodal to L, band 4 was still cathodal to L.     

中国蚜科新纪录,3

在调查云南森林昆虫中发现下述种类为我国首次纪录。 埃二尾蚜Cavariella aegopodii(scopoli,1763),中国新纪录。采自云南丽江(黑龙潭,1980.V.25),各型孤雌蚜。寄主为茴香,取食于嫩叶反面,叶向反面微卷。活体绿色,有翅孤雌蚜腹部背面有斑纹,有翅若蚜背面有翠绿色斑。国外分布于日本,欧洲,非洲,澳洲和美洲。 康二尾蚜Cavariella konoi Takahashi,1939,中国新纪录。采自云南剑川(老君山,3100m,1980     

中国蚜科新纪录,4

在调查云南森林昆虫中发现下述种类为我国首次纪录。 大尾小长管蚜Macrosiphoniella grandicauda Takahashi et Kuwana, 1963,中国新纪录。采自云南丽江(林科所1980.V.23),各型孤雌蚜。寄主为艾蒿,盖满3—4寸嫩梢。活体叶绿色,体稍扁。不易从植物上坠落。国外分布于朝鲜、日本和印度。     

鄂东南早白垩世灵乡群孢粉组合

本文根据从大冶灵乡-陈重山剖面的中部、灵乡狮子山东侧采坑和鄂城太和1孔的相当层位中所获得的孢粉组合(共67属120余种,其中新种9个,新联合2个),认为灵乡群孢粉组合属于 Classopollis、Psophosphaera-Cicatricosisporites、Schizaeoisporites-没有或极个别的出现被子植物花粉的组合类型,其地质时代应为早白垩世早期-中期(凡兰吟期-巴列姆期)。并推测鄂东南地区当时的气候属于偏干旱的热带-亚热带型。