青海贵德、共和两盆地晚新生代哺乳动物

本文记述了青海省贵德及共和两盆地的几个含晚新生代哺乳动物化石地点的地层剖面及采自18个地点的26种(代表20个属)哺乳动物化石.对其中的 Myospalax arvicolinus, Microtus, Anancus, Leptobos crassus gonghenensis subsp. nov., L. vallisarni, Bison (Superbison) crassicornis, Boopsis breviceps作了较详细的描述和讨论.通过对动物群的分析初步确定了盆地主要堆积物的时代——贵德盆地:上新世—早更新世;共和盆地:早—中更新世,并简略探讨了两盆地的发育历史.     

Attachment of DNA to nucleolar and nuclear skeletal structures as visualized by Kleinschmidt molecular spreading

Co-isolated residual nuclear shells and residual nucleoli from membrane-depleted rat liver nuclei were spread according to Kleinschmidt's method. Comparison of the spread residual structures isolated from nuclear shells and spread pore complex-lamina isolated from nuclear envelopes showed that these residual structures are morphologically identical. Furthermore, our nuclear shell isolation procedure allowed visualization of DNA strands bound to a granular component of the lamina. The fragmentation of nuclear shells allowed us to obtain well-spread nucleolar remnants, in which we observed DNA strands anchored on a residual nucleolar network attached to the lamina. The different molecular features revealed by the spreading of residual nucleolar structures suggest that both non-transcribing nucleolar DNA and active ribosomal genes are linked to the nucleolar network. Although the exact nature of this network remains to be defined, the results of the present study strongly suggest that the DNA molecules of the chromosomes bearing ribosomal genes have many sites of attachment to a non-chromatin nucleolar network which can be referred to as a nucleolar skeletal complex.     

Hypoxia-induced periodic breathing in newborn lambs

This study was designed to elucidate the effect of hypoxia on the breathing rhythmicity and the effect of hypoxia on periodic breathing (PB) in two groups of newborn lambs (less than 2 days and 10 days of age). Lambs undergoing a hypoxic ventilatory test [0.08 inspired O2 fraction (FIo2) for 13 min] experienced no apnea or PB in hypoxia, but all developed PB during the 1-min period immediately after their abrupt return to 0.21 FIo2. This PB occurred when alternation of arterial PO2 and PCO2 in mild hypoxic and hypocapnic conditions induced an overshoot-undershoot response of the chemical drive to breathe. The magnitude of PB was found to be greater in the animals with a higher peripheral chemoreflex sensitivity to hypoxia but ceased altogether when the hypoxic-hypocapnic conditions were resolved. When these conditions were removed more quickly, that is, when the animals were returned either to 0.50 FIo2 or to 0.03 FIco2, no PB was observed. To clarify the role of hypoxia as a central depressant on the genesis of PB, we tested to determine whether additional central tissue hypoxia, using carboxyhemoglobin (30%), would worsen the episodes of PB. No effect on breathing rhythmicity was observed. These findings suggest not only that, in newborn animals and adults, the mechanisms of post-hypoxia-induced PB are identical but that the PB elicited in mild hypoxic conditions is a peripheral chemoreflex-mediated event rather than a centrally mediated one.     

中三叠世多板类在我国的首次发现

报道我国首次发现的三叠纪多板纲(Polyplacophora)鳞肋目(Lepidopleurina)鳞肋科(Lepidopleuridae)的—新属——中国石鳖(Sinochiton).新属保存较完整,贝体中等大,椭圆形,长宽比为1.44∶1;中间板宽远大于壳长,长方形,半圆形拱凸,壳顶不突出,后缘近直,中心区十分宽大,侧区很窄,或不明显,缝合片及嵌插板不发育;贝体具圆形环带.新属与菊石 Balatonites 共生,时代属 Anisian 期.新属与北美下二叠统的 Ochmazochiton Hoare, 1984 及宾夕法尼亚系的 Pedanochiton Debrock, Hoare et al 近似,它们之间可能存在着亲缘关系.     

FVB mice transgenic for the H-2Db gene become resistant to persistent infection by Theiler's virus.

The DA strain of Theiler's virus causes a persistent infection of the white matter of the spinal cord with chronic inflammation and primary demyelination. Inbred strains of mice differ greatly in their susceptibility to this disease. It has been shown that both viral persistence and demyelination are controlled mainly by a gene located in the H-2D region. This raised the possibility that the H-2D gene itself controls viral persistence, which in turn determines demyelination. In the present work we introduced the H-2Db gene of resistant C57BL/6 mice into the genome of susceptible H-2q FVB mice and showed that the FVB mice become resistant to persistence of the infection and did not develop inflammatory lesions.     

PRELIMINARY STUDY ON INCREASING GROWTH AND REJUVENATION FOR OSSIFIED EELS WITH THE MICROECOLOGICS

This paper was adopting intestinal normal microbiota: Micrococcus tntestinalt, sp. and Beneckea campbell, and were prepared to microecologics, also gave a rebuild of intestinal micro ecospecies for ossified eels, and research effect of increasing growth and rejuvenation to them, by the microecologics. Moreover, specially to set up double-control, including a thyroideum medicament and an empty test group, for the comparison and analysis. Our results show that the intestinal microecologics of eel, for increasing growth and rejuvenation to ossified eels, that are botth achieve striking effect. But looked the thyroideum for increasing growth to ossified eels were be very effective. Nevertheless, which for rejuvenation was failed to take effect.Furthermore, we inc-lined to believe that the could be possible still significance of effect, if again added intestinal obligate anserobes of adult eels, and the cerebiogen into this microecologics.     

浙西早寒武世梅树村期棒状化石

该文记述了浙江省西部江山县新塘坞地区灯影组(梅树村期)中新发现的矿化骨骼化石——浙江棒(新属)Zhejiangorhabdion gen.nov.。该化石的形态与以往化石类群均不相同,为个体微小的棒状,表面具较复杂的纹饰,不同个体间的纹饰都有一定变化,推测是动物体内不同部位的骨棒所具有的特征,代表了一个新的化石类群。新属的发现丰富了梅树村期动物群的内容,对了解具骨骼动物群体在这一时期的演化具有一定的意义。     

黑龙江宁安盆地穆棱组及其孢粉型组合新发现

黑龙江宁安盆地是一个具有油气勘探远景的中小型盆地,主要目的层为下白垩统。新发现了一套相当于邻区穆棱组的地层,孢粉化石十分丰富,建立了５个孢粉组合带,通过对两口石油探井生物地层的研究,建立了该舅地新的地层层序,并对穆棱组的时代和沉积环境进行了讨论。