南美斑潜蝇室内饲养及生物学特性

通过观察在豇豆上一个完整世代的饲养试验,对南美斑潜蝇的生活习性、形态特征进行了描述。结果表明,在室温(25±1)℃,RH75%～85%,光照14h条件下,一个世代为16～17天;成虫在叶片上、下表面皆可刺孔取食,幼虫取食叶片栅栏组织、海绵组织区分不明显。     

Experimental Researches on Carcinogenesis or Tumorigenicity of MDCK Canine Kidney Cell(CKC) Lines and Analysis of Their Chromosome Karyotypes

The chromosomal number variations & structural aberrations of the MDCK cell line, primary feline or canine kidney cell(FKC or CKC) and Hela cell line were investigated and their karyotypes of conventional chromosome bands were analyzed. The carcinogenesis or tumorigenicity testing of these cell lines in about 232 nude mice and for colony formation in soft agarose and for haemagglutination under different concentration of plant lectins of these cells were carried out. Under the prerequisite that the incidence of cancer or tumor in negative-control nude mice inoculated subcutaneously with primary feline or canine kidney cell cultures purified in vitro at passage 3 was 0 (0/22) and 0 (0/10), respectively. The incidence of the progressively-growing malignant tumor(MT) in positive-control nude mice inoculated subcutaneously with Hela cell cultures of KB, X, or NM20/X strain was 10/10, 25/25 and 5/51, respectively. The results showed that the incidence of tumor in nude mice with tetrapioid YA strain of MDCK cell during 20 - 45 passages, with hypodiploid JB strain of MDCK cell on passage 25, with di-and hypoploid JC strain of MDCK cell during 2 - 15passages or with hypoploid M strain of MDCK cell during 9 - 27 passages was 28/58, 1/5, 4/18 and 0/31,respectively. The chromosomal analysis results showed that the ratio of difference in the rate of modal chromosome number between high (mcs + n) and lowest (mcs)passages was not more than 5 % - 15 % and the structure aberrations was generally 0 - 3%. These results proved that the genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is species-specific. MDCK line has tumorigenicity no matter what its chromosome karyotype is, at least it has very low tumorigenicity even when its modal chromosome number is hypoploid. The repeatedly frozen, thawed and split controls of tumorigenicity-positive cell lines(X strain of Hela, M strain of BHK-21, JA strain of Vero, YA strain of MDCK) have much lower tumorigenicity or are even non-carcinogenesis, and the repeatedly frozen, thawed and split controls of very low tumorigenicity cell lines (M or JC strain of MDCK) are certainly non-carcinogenic and never have increased tumorigenicity.It is thus evident that MDCK cell of M, JB or JC strain can be approved as substrate for the preparation of attenuated viral vaccines, but MDCK cell of YA strain can not be approved as substrate for the preparation of comattenuated viral vaccines. In summary, all strains of MDCK cell line have tunorigenicity, at least have low tumorigencity, never have non-cancinogenic MDCK, but very low tumorigenicity MDCK cell strains can certainly be used for the approval production of canine viral vaccines if the DNA content in viral cell cultures was remarkably decreased through conventional means in manufacturing process. Therefore, the master cell stock and working cell bank of MDCK line used for vaccine manufacture were established in China, which are free of infectious agents, and described with respect to cytogenetic characteristics and tumorigenicity. Tests showed that there were correlations among cell line chromosome number variations, anchorage independence in soft agarose, haemagglutination under plant lectins, and tumor-forming ability in nude mice, thus all the in vitro tests are economic, simple and reliable means for monitoring the tumor-forming ability of MDCK line in nude mice.     

黄精种子形态及发芽特性研究

研究了黄精果实及种子不同发育时期内源激素ABA含量的变化与收获种子类型,以及不同类型黄精种子形态、生活力、千粒重与发芽的相关性.结果表明:3种类型黄精种子属不同发育时期的种子,其外观形态和各种物理特性指标都存在一定差异,其中黄皮种子最大,长、宽平均值分别为4.372 mm和3.710 mm,活性较弱,发芽率45.16%;绿皮种子的千粒重、生活力、发芽率均最高,分别为35.6 g、85%和85.71%;黑皮种子基本没有生活力.说明绿皮种子质量最好,黄皮种子次之.     

Effects of inbreeding on nodal root system morphology and architecture of white clover (<Emphasis Type="Italic">Trifolium repens</Emphasis> L.)

Plants of white clover (Trifolium repens L.) cultivar Crau, a self-fertile Crau genotype, and nine generations of inbred progeny were raised in sand culture in a glasshouse experiment. Digital images of the root systems were made and root morphological characteristics were determined on all the plants. Root architectural parameters were measured on the Crau parent and the S₁, S₄, S₆, and S₉ inbred lines. The clover roots became shorter and thicker with inbreeding but the number of root tips per plant was unchanged. Root architecture (branching pattern) was largely unaffected by inbreeding. It is concluded that inbreeding white clover will lead to shorter, thicker roots, and reduced nutrient uptake efficiency compared with the parent clover. The degree to which these deleterious traits are overcome during the development of F₁ hybrids needs to be determined.     

北方森林细根对氮沉降和二氧化碳浓度升高的响应

北方森林是全球第二大生物群区,约占全球森林面积的30%,尽管其细根生物量仅占森林生态系统很小的一部分,但其周转率更快,更易分解,因此,其对土壤碳循环和大气CO_2通量贡献很大。笔者综述了氮沉降和CO_2浓度升高的背景数据,总结了细根对二者变化的响应,主要从细根的形态特征、解剖结构和生理功能方面入手,探讨了其对氮沉降和CO_2浓度升高的响应。结论如下:(1)大气氮沉降量一直处于上升状态,与人类活动密切相关的有机氮量所占比例逐渐加大,而无机氮中NH_4~-N和NO_3~-N的变化趋势表现不同;(2)大气CO_2浓度一直呈上升趋势,细根形态特征、解剖结构和生理功能对其表现出明显的响应;(3)树种、年龄、土壤类型等都会改变细根形态、解剖结构和生理功能对氮沉降和CO_2浓度升高的响应结果,但改变的程度不同。研究结果可为北方森林乃至温带森林生态系统功能对氮沉降和CO_2浓度升高的响应提供参考依据和数据支持。     

内蒙古地区家畜肿瘤的调查及其病理形态学研究

本文对内蒙古自治区777844头家畜(绵羊、山羊、牛、马、骡和骆驼)的调查,共检出肿瘤76例,分属25种肿瘤:山羊鼻腔腺瘤、绵羊肺腺瘤,绵羊乳腺瘤、牛肝细胞腺瘤、绵羊和牛的胆管细胞癌与肝细胞癌、绵羊和马的肾腺癌、牛腺癌、绵羊肾上腺皮质癌、牛纤维瘤、牛韧带状瘤、牛间皮瘤、牛和绵羊的海绵状血管瘤、绵羊淋巴管瘤、骆驼骨软骨瘤、骡纤维肉瘤、绵羊肉瘤、绵羊和牛的横纹肌肉瘤、牛软骨肉瘤、绵羊淋巴肉瘤、牛神经鞘瘤、马脑膜瘤、绵羊卵巢睾丸母细胞瘤、牛癌肉瘤、马和绵羊的恶性黑色素瘤。调查表明牛的肿瘤检出率比羊的肿瘤检出率高,山羊鼻腔腺瘤呈地方性流行,绵羊肺腺瘤分布有一定的区域,其余肿瘤均为散发。文中对各种肿瘤的形态结构均作详细描述。     

氮肥与密度互作对单粒精播花生根系形态、植株性状及产量的影响

为明确花生单粒精播适宜的氮肥水平和种植密度,本研究于2018年和2019年以‘花育22’为供试花生品种,设置3个氮肥水平(0 kg hm^–2, N0; 60 kg hm^–2, N1; 120 kg hm^–2, N2), 3个种植密度(7.93万株hm^–2, D1; 15.86万株hm^–2,D2; 23.79万株hm^–2, D3),采用二因素裂区试验设计,研究氮肥、密度及其互作对单粒精播花生根系形态、植株性状及产量的影响。氮肥对花生根长、根表面积、根体积、根干重的影响不显著,而密度的影响显著。单株根长、根表面积、根体积及根系干重随密度的增加而降低, D1显著高于D2和D3, D2、D3处理间差异不显著;单位面积根长、根表面积、根体积及根系干重随密度的增加而增加, D1显著低于D2和D3, D2、D3处理间差异不显著。氮肥和密度互作对2019年收获期单位面积根长、根表面积的影响显著,与D1相比, N1处理下D3的增幅显著高于N0和N2处理。氮肥及氮肥与密度互作...     

土壤硒形态及其相互转化因子的研究

近年来,天然富硒农产品的生产及加工成为研究热点。决定植物硒含量的主要因素为土壤有效形态硒含量,因此了解土壤硒形态及转化关系,寻找提高硒有效性方法尤为重要。笔者通过对国内外硒研究文献的整理和分析,对土壤硒形态的分类、土壤硒形态间的转化及提高土壤硒有效性的因素等进行深入分析。了解土壤硒化学形态和浸提形态及其关系,进一步研究不同形态间转化的驱动因子,寻找提高富硒区土壤硒有效性的方法。结合不同富硒区域土壤及作物特点,采取不同的硒素活化方法,为进一步开展相关研究提供更多科学依据。     

Effects of CENP-W down-regulation on human glioma U87 cells

AIM: To study the effect of centromere protein W (CENP-W) down-regulation on human glioma U87 cells.METHODS: Small interfering RNA (siRNA) was used to inhibit the expression of CENP-W in the U87 cells. The interference effect of siRNA was evaluated by RT-qPCR and Western blot. The proliferation of the cells was analyzed by MTT assay, BrdU staining and colony formation experiment. Transwell chamber assay was used to detect the invasion ability of the cells. The cell migration ability was measured by a scratch test. The changes of the cell cycle distribution and apoptosis were analyzed by flow cytometry.RESULTS: The results of MTT assay, colony formation experiment and BrdU staining showed that the cell proliferation and colony formation abilities in experimental group were significantly lower than those in control group and negative control group. The results of Transwell and scratch experiments showed that the migration and invasion abilities in experimental group were weaker than those in blank control group and negative control group. The results of flow cytometry analysis showed that the cell cycle distribution in experimental group was arrested in G₀/G₁ phase. The percentage of apoptotic cells in experimental group was higher than that in control group (P<0.05).CONCLUSION: Down-regulation of CENP-W expression inhibits the proliferation, migration and invasion of human glioma cells and promotes the apoptosis of the cells, suggesting that CENP-W may be a potential target of gene therapy for human glioma.     

稀土细胞毒理效应研究进展

稀土农用给中国农业带来丰厚回报,但稀土的环境安全问题也引起了中外科学家的关注。本文结合国内外最新研究成果,从稀土细胞毒理学角度概述了稀土在细胞内定位,稀土对细胞膜、细胞器、细胞遗传物质及细胞信使物质的毒理效应,并对稀土细胞毒理学的研究进行了展望。