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991.
有或没有基细胞是毛鞘藻属(Bulbochaets)与枝鞘藻属(Oedocladium)的区别之一。这里叙述了Mrozinska在其专著(1985)中,将Oedocladium indicum Kama附图(即模式图)上的一个基细胞错误地移置到Oe.PrescottiiIslam上去的情况。 相似文献
992.
津白_3侏儒小鼠(dW~t)是1982年从津白_3纯系小鼠(TA_3)中发现,进而培育成侏的变种。本实验应用免疫细胞化学技术,对dw ̄t小鼠垂体前叶生长激素(GH)细胞进行观察,并根据体视学原理进行定量分析,以探讨dw~t小鼠是否存在垂体发育缺陷。实验结果显示,dw~t小鼠GH细胞的体积密度(Vv)和数密度(Nv)值均低于正常对照组,P<0.01~0.001。表明dw~t小鼠由于垂体前叶GH细胞数量减少,导致GH分泌不足,从而形成侏儒。 相似文献
993.
本实验合并应用枸杞有效成份和大蒜有效成份,作用于U_14腹水型宫颈癌小鼠,腹腔注射第四天,发现一般状况改善,取腹水观察,癌细胞破损,DNA、RNA荧光染色强度减弱,有大量白细胞和巨噬细胞围绕;流式细胞分析G_1期细胞堆积,超微结构显示胞质中线粒体肿胀,嵴破坏甚至中空,粗面内质网扩大、脱颗粒,肯定了其作用的效果。此因枸杞有效成分活化巨噬细胞与肿瘤细胞紧密结合而起到溶瘤作用,与大蒜有效成分直接杀伤而作用维持短暂结合起来,可大大提高抗癌作用。 相似文献
994.
喹诺酮类药物抗乙型肝炎病毒体外实验研究 总被引:4,自引:0,他引:4
本文以2.2.15细胞株为模型,以HBsAg、HBeAg、HBVDNA、细胞存活率为观察指标,综合评价了喹诺酮类药物吡哌酸(PipemidicAcid)、氟哌酸(Norfloxacin)、环丙氟哌酸(Ciproflosxacin)、氟嗪酸(Ofloxacin)体外抗HBV效果。结果表明:吡哌酸、氟哌酸、环丙氟哌酸、氟嗪酸对HBsAg、HBeAg50%抑制浓度(ID_(50))分别为11μg/ml、64μg/ml、93μg/ml、105μg/ml和199μg/ml、111μg/ml、24μg/ml、217μg/ml,细胞存活率为50%时的药物浓度(CD_(50))分别为219μg/ml、90μg/ml、181μg/ml、169μg/ml,在所选定的用药浓度范围内不同程度抑制培养上清液及细胞内HBVDNA及其复制中间体的产生。尤其对超螺旋结构DNA(scDNA)有不完全抑制作用。 相似文献
995.
Recently, we demonstrated that the major proteins from bovine seminal plasma BSP-A1, -A2, -A3 and -30-kDa (collectively called BSP proteins) specifically interact with choline phospholipids. These proteins coat the surface of the spermatozoa after ejaculation and are believed to play an important role in membrane modifications occurring during capacitation. In this study we determined the isoelectric point (pl) and analysed the molecular heterogeneity of BSP proteins. Total protein from bovine seminal plasma (CBSP) and purified BSP proteins were iodinated using chloramine T. Samples were reduced, denatured, separated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), and visualized by autoradiography. Analysis of CBSP proteins demonstrated the presence of polypeptides migrating in the pH range of 3.5–7.8 and at molecular weights (Mr) between 6 and 100 kDa. Many isoforms of each BSP protein were found when purified iodinated proteins were analysed by 2D-PAGE. BSP-A1 was found at a Mr of 16.5 kDa and in the range of pl of 4.7–5.0; BSP-A2 at 16 kDa and at a pl of 4.9–5.2; BSP-A3 at 15 kDa and at a pl of 4.8–5.2, and BSP-30-kDa at 28 kDa and at a pl of 3.9–4.6. Similar results were obtained with immunolocalization of BSP proteins after Western blot using specific antibodies. The treatment of purified iodinated BSP proteins with neuraminidase increased the pl of BSP-30-kDa to 4.8–5.0 and decreased its Mr to 25 kDa, but no change was observed for BSP-A1, -A2 and -A3. The treatment of BSP proteins with sulfatase or acid phosphatase modified neither their Mr nor their pl. Furthermore, when CBSP proteins were separated in 2D-PAGE and the gels stained for glycoproteins with dansyl hydrazine, BSP proteins were among the major glycoproteins found in the bovine seminal plasma. In conclusion, BSP proteins are acidic and have several isoforms. Furthermore, the heterogeneity of BSP-30-kDa is mainly due to its sialic acid content. © 1994 Wiley-Liss, Inc. 相似文献
996.
Takashi Ninomiya Masumi Hirabayashi Junko Sagara Atsushi Yuki 《Molecular reproduction and development》1994,37(3):276-283
Fragments containing 5′ flanking regions of four bovine milk protein genes—alpha lactalbumin (bαLA), alpha S1 casein (bαS1CN), beta casein (bβCN), kappa casein (bkCN)—and mouse whey acidic protein (mWAP) gene were prepared by PCR and ligated to human growth hormone (hGH) gene. These recombinant DNAs were microinjected into rat embryos to produce transgenic rats, and the functions of the 5′ regions to direct secretion of hGH in the milk were tested. Although milk was obtained only in 5 of 19 mWAP/hGH rat lines, more than two-thirds of the rats carrying the other four DNAs produced milk. More than 80% of the lactated rats carrying bαLA/, bβCN/, and mWAP/hGH, and 33% of the laclated bαS1CN/hGH rats secreted detectable amounts of hGH (> 0.05 μg/ml) in the milk. In some rats, the hGH concentrations in the milk were comparable to or more than that of the corresponding milk protein in bovine milk. The ranges of hGH concentrations in the milk of bαLA/, bβCN/, bαS1CN/, and mWAP/hGH rats were 1.13–4,360 μg/ml, 0.11–10,900 μg/ml, 86.8–6,480 μg/ml, and 6.87–151 μg/ml, respectively. HGH was also detected in the sera of these rats, and some abnormalities of growth and reproduction were observed. All but one virgin mWAP/hGH rat secreted up to 0.0722 μg/ml of hGH in the serum, and more than half of them showed abnormal fat accumulations at their abdomen. None of the bαCN/hGH rats secreted detectable amount of hGH into their milk, whereas 8 of the 11 lines secreted hGH into their sera. For the production of hGH in transgenic rat milk, the 5′ region of bαS1CN was shown most suitable, because the bαS1CN/hGH rat secreted > 6,000 μg/ml of hGH into the milk and could be reproduced. © 1994 Wiley-Liss, Inc. 相似文献
997.
在合成磷酰蛋白的模型化合物体N-(O,O-二烷基)磷酰化氨基酸(1)的基础上,首次合成了有机磷生命化学的模型化合物──核蛋白基本单元N-(O-烷基,O-核苷)磷酰化氨基酸(2),并对上述物质进行了分离、鉴定、比较了两种模型的合成方法。这对在小分子水平上,深入研究磷酰基的参与作用和蛋白质与核酸之间的互相作用机理提供了较好的模型化合物。 相似文献
998.
CHISA YASUNAGA MASAKO FUNAKOSHI TAKESHI KAWARABATA 《The Journal of eukaryotic microbiology》1994,41(2):133-137
ABSTRACT. Spores of Nosema bombycis Y9101, isolated from the beet armyworm, Spodoptera exigua , were primed with an alkaline solution and inoculated into Antheraea eucalypti cell cultures. Infected cells were subcultured every five days at three cell densities (2.5 × 103 , 5.0 × 103 , and 1.0 × 104 cells/cm2 ). A difference was observed in the spread of N. bombycis Y9101 infection between low-density and higher-density cultures of host cells. The host cell density did not affect the productivity of secondary infective forms of the parasite. The principal factor determining the rate of microsporidian infection in vitro was the number of host cells existing within the reach of extruded short-coiled polar tubes from spores germinated intracellularly. 相似文献
999.
Andrea Casasco Marco Casasco Antonia Lcaro Cornaglia Marco Danova Monica Giordano Alberto Calligaro 《Biotechnic & histochemistry》1994,69(2):112-117
PC10 is a monoclonal antibody to proliferating cell nuclear antigen, a nuclear protein associated with the cell cycle. We have evaluated the effects of tissue fixation on PC10 immunoreactivity in sections of paraffin embedded rat tissues. Immunoreactivity was well preserved in tissues after fixation with alcohol-based solutions for 3-24 hr. Fewer PC10-positive cells were detectable in samples fixed with formaldehydecontaining solutions compared with samples fixed with alcohol for the same time. Loss of PC10 immunoreactivity in formaldehyde fixed tissues was progressive, and quantifiable as early as after 3 hr fixation. Consequently, alcohol-based fixatives are strongly recommended for any immunocytochemical prospective study using PC10 antibody. In contrast, loss of PC10-immunoreactivity is always predictable, but difficult to quantitate, using formaldehyde fixed specimens. This aspect should be considered when using PC10 antibody in retrospective studies with routinely-processed archival material. 相似文献
1000.
Einar Lystad Arne T. Høstmark Cecilie Kiserud Aage Haugen 《In vitro cellular & developmental biology. Animal》1994,30(9):568-573
Summary The protective influence of bovine serum albumin against growth inhibition caused by fatty acids was studied in human hepatoma
(HepG2) and immortalized human kidney epithelial (IHKE) cells. In general, growth inhibition by unsaturated fatty acids (0.15
mmol/liter) increased with increasing number of double bonds. For HepG2 cells crude albumin (1g/100 ml) did not greatly modify growth inhibition by arachidonic, eicosapentaenoic, and docosahexaenoic acid. With oleic,
linoleic, and linolenic acids, crude and defatted albumin stimulated cell growth. In contrast, for IHKE cells both albumins
counteracted growth inhibition by unsaturated fatty acids to approximately the same extent. When HepG2 cells were cultured
in the presence of saturated fatty acids (0.3 mmol/liter), C2, C6, and C8 had no or little inhibitory effect. C10 and C12
inhibited cell growth appreciably, whereas C14, and especially C16, had poor inhibitory effects. Crude albumin counteracted
growth inhibition by all these fatty acids. In contrast, defatted albumin had little or no effect (except against C10 and
C12), and even increased the growth inhibition by C14 and C16. With unsaturated fatty acids there seemed to be an inverse
relationship between cell growth and the concentration of thiobarbituric acid reactive substances (TBARS) in media. Vitamin
E abolished growth inhibition (and the increase in TBARS concentration) by unsaturated fatty acids. The complex interaction
between fatty acids and albumins calls for great caution when interpreting data on growth effects. 相似文献