人工饲养条件下马来熊(Helarctos malayanus)生长发育和行为特点的初步研究

1987年9月至1989年8月,笔者对来自云南瑞丽的2只雄性马来熊成体和7只幼体(3♂,4♀♀)在人工饲养条件下进行了观察研究,本文报道在不同生长时期的不同饲料配方、幼熊感觉器官的发育、齿式的形成、外部形态的变化、体重的生长方法及行为。     

Ultrastructure of the micropyle and its relationship to pollen tube growth and synergid degeneration in sunflower

Summary Ultrastructural studies made on the micropyle of sunflower before and after pollination resulted in the following observations. (1) The micropyle is closed instead of a hole or canal. The inner epidermis of the integument on both sides of the micropyle is in close contact at the apex of the ovule. The boundary between the two sides consists of two layers of epidermal cuticle. (2) The micropyle contains a transmitting tissue. The micropyle is composed of an intercellular matrix produced by the epidermal cells of the integument. (3) The micropyle is asymmetrical, and is much wider on the side proximal to the funicle. On the funicle side the cells adjacent to the micropyle are similar to those of the transmitting tissue: they have large amounts of intercellular matrix and contain abundant dictyosomes, rough ER, and starch grains, and provide an appropriate environment for growth of the pollen tubes. The cells distal to the funicle are rich in rough ER and lipid bodies; they lack large intercellular spaces. (4) The micropyle is variable in the axial direction, i.e., it is much larger and more asymmetric at the level distal to the embryo sac than at a level close to the embryo sac. After pollination, one to four pollen tubes are seen in a micropyle. During their passage through the micropyle, most pollen tubes are restricted to the side proximal to the funicle. There is a greater tendency (81%) for the degenerate synergid to be located toward the funicle, i.e., at the same side as the pollen tube pathway. The data indicate a close relationship between micropyle organization, orientation of pollen tube growth, and synergid degeneration.     

Measurement of free amino acid levels in ultrafiltrates of blood plasma by high-performance liquid chromatography with automatic pre-column derivatization

Although there are many techniques available for the analysis of amino acids, deproteinization is still one of the major problems in the analysis of amino acids in physiological fluids. The method used to prepare the plasma and to remove the plasma protein has a marked effect on the final results. The most widely used method of deproteinization is precipitation with 5-sulphosalicylic acid followed by centrifugation to remove the precipitated protein. We have not had success in using this deproteinization agent for the analysis of plasma amino acids by a high-performance liquid chromatographic method with automatic pre-column o-phthaldialdehyde—3-mercaptopropionic acid and 9-fluorenylmethyl chloroformate derivatization because of the adverse effect of the sulphosalicyclic acid supernatant on the quantitation and separation. Ultrafiltration was used as an alternative method for the preparation of plasma samples in this experiment. The results were satisfactory for the analysis of plasma amino acids in 1500 samples during a period of four years. Some factors that might influence the results of the ultrafiltration were investigated.     

幼年大鼠诱发排卵条件下卵巢前列腺素(PGs)的含量变化及其生理作用

本实验用幼年大鼠经PMSG/hCG诱发排卵,研究了印巢PGE_2、PGF_(2α) 、6-酮-PGF_(1α) 及TXB_2在排卵过程中的变化。实验表明卵巢PGE_2、PGF_(2α) 及6-酮-PGF_(1α) 在排卵前达到峰值,在排卵后,均趋下降。TXB_2未出现明显变化。受试动物经消炎痛处理后,不仅使排卵受到严重抑制,而对上述三种PGs在排卵前的上升也表现了显著的抑制。提示在卵泡破裂过程中PGs的重要调节作用,PGE_2、PGF_(2α)均可能参与排卵,其中尤以PGE_2的作用最为显著。     

Structures of cytokinins influence synergistic production of ethylene

Twenty-five naturally occurring cytokinins and structurally related compounds were tested for their ability to promote ethylene production synergistica     

我国主要蚧螬对乳状菌的敏感性

我国主要蛴螬种类对乳状菌(Bacillus popilliae Dutky)(以下简称B.p.)敏感性的测定:已有14种蛴螬能注射感染B.p.。超出了Dutky(1963)的记录。敏感寄主毛喙丽金龟(Adoretus hirsutus Ohaus)、四纹丽金龟(Popillia quadriguttata F.)、暗黑鳃金龟(Holotrichia morosa Waterh)、黑棕鳃金龟(Apogonia cupreoviridis Fairm.)的幼虫注射感病率达91.6—100%。E.P.拌种喂食四纹、阔胸犀金龟(Pentodon patruelis Friv.)的幼虫,感病率分别达到68.9%和50%。B.p.拌土喂食阔胸幼虫,感病率为28.5%,田间小区试验,保苗效果达49.5%,虫口减退率达40.0%。定向转主驯化B.p.对华北大黑鳃金龟(Holotrichia oblitaFald.)幼虫,注射感病率已由不感病提高至感染率34.6%。 利用病原微生物防治害虫是综合防治的一个重要环节,应用乳状菌防治金龟子幼虫是以菌治虫方面值得研究的课题之一。 早在本世纪三十年代已发现日本金龟子(Popillia japonicaNewm.)幼虫罹患乳臭病的事实。1940年Dutky首先对其病原菌(B.popilliae)和(B.lentimorbus)进行命名和描述,继之White 1941,Beard 1945等对其生理生化、致病机理等作了较多的研究。五十年代后,对这类菌的超显微结构、离体培养等研究更为广泛。它作为第一个商品化的细菌杀虫剂,美国最早用于防治草地下的日本金龟子幼虫,取得了显著的效果。 我国蛴螬种类在千种以上,在华北、东北、西北的农田里为害十分严重,由于蛴螬的种类多,分布广,因而寄生于蛴螬的乳状菌株也相当丰富。目前已从主要蛴螬种类上陆续分离出一些菌株,将为我国开发利用乳状菌提供资源。近几年来,我们除对我国菌株进行研究外,也做了引进菌种Bacillus popilliae Dutky对我国主要蛴螬敏感性的研究,本文主要报道这方面结果。     

Ginsenoside Rg1 protects H9c2 cells against nutritional stress-induced injury via aldolase /AMPK/PINK1 signalling

Insufficient nutrients supply will greatly affect the function of cardiac myocytes. The adaptive responses of cardiac myocytes to nutritional stress are not fully known. Ginsenoside Rg1 is one of the most pharmacologically active components in Panax Ginseng and possesses protective effects on cardiomyocyte. Here, we investigate the effects of ginsenoside Rg1 on H9c2 cells which were subjected to nutritional stress. Nutritional stress-induced by glucose deprivation strongly induced cell death and this response was inhibited by ginsenoside Rg1. Importantly, glucose deprivation decreased intracellular ATP levels and mitochondrial membrane potential. Ginsenoside Rg1 rescued ATP levels and mitochondrial membrane potential in nutrient-starved cells. For molecular mechanisms, ginsenoside Rg1 increased the expressions of PTEN-induced kinase 1 (PINK1) and p-AMPK in glucose deprivation treated H9c2 cells. Reducing the expression of aldolase in H9c2 cells inhibited ginsenoside Rg1′s actions on PINK1 and p-AMPK. Further, the nutritional stress mice were used to verify the mechanisms obtained in vitro. Ginsenoside Rg1 increased the expressions of aldolase, p-AMPK, and PINK1 in starved mice heart. Taken together, our results reveal that ginsenoside Rg1 limits nutritional stress-induced H9c2 cells injury by regulating the aldolase /AMP-activated protein kinase/PINK1 pathway.     

Comprehensive profiling of accessible surface glycans of mammalian sperm using a lectin microarray

It is well known that cell surface glycans or glycocalyx play important roles in sperm motility, maturation and fertilization. A comprehensive profile of the sperm surface glycans will greatly facilitate both basic research (sperm glycobiology) and clinical studies, such as diagnostics of infertility. As a group of natural glycan binders, lectin is an ideal tool for cell surface glycan profiling. However, because of the lack of effective technology, only a few lectins have been tested for lectin-sperm binding profiles. To address this challenge, we have developed a procedure for high-throughput probing of mammalian sperm with 91 lectins on lectin microarrays. Normal sperm from human, boar, bull, goat and rabbit were collected and analyzed on the lectin microarrays. Positive bindings of a set of ~50 lectins were observed for all the sperm of 5 species, which indicated a wide range of glycans are on the surface of mammalian sperm. Species specific lectin bindings were also observed. Clustering analysis revealed that the distances of the five species according to the lectin binding profiles are consistent with that of the genome sequence based phylogenetic tree except for rabbit. The procedure that we established in this study could be generally applicable for sperm from other species or defect sperm from the same species. We believe the lectin binding profiles of the mammalian sperm that we established in this study are valuable for both basic research and clinical studies.