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11.
抗胃癌细胞系单克隆抗体PD4的初步研究 总被引:1,自引:0,他引:1
以胃癌细胞系MGC803免疫Balb/c小鼠,取其脾细胞与小鼠骨髓瘤细胞NS-1融合。经选择培养、筛选及克隆化,获得恒定地分泌抗胃癌细胞系单克隆抗体(MoAb)的杂交瘤细胞系PD4。MoAb PD4与3/4胃癌细胞系有强结合反应,与4/4肺癌细胞系有弱结合反应,但与淋巴细胞、ABO红细胞、骨髓细胞、二倍体成纤维细胞及经检测的其他肿瘤细胞均无反应。PD4抗原主要表达于靶细胞的膜上,不耐热,为分子量40kD的蛋白性抗原。该抗原与HLA抗原系统,血型抗原系统无关,亦不同于其他作者所报告的其他胃癌相关抗原。 相似文献
12.
13.
14.
Epithelial cytoskeletal framework and nuclear matrix-intermediate filament scaffold: three-dimensional organization and protein composition 总被引:60,自引:26,他引:34
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Madin-Darby canine kidney (MDCK) cells grow as differentiated, epithelial colonies that display tissue-like organization. We examined the structural elements underlying the colony morphology in situ using three consecutive extractions that produce well-defined fractions for both microscopy and biochemical analysis. First, soluble proteins and phospholipid were removed with Triton X-100 in a physiological buffer. The resulting skeletal framework retained nuclei, dense cytoplasmic filament networks, intercellular junctional complexes, and apical microvillar structures. Scanning electron microscopy showed that the apical cell morphology is largely unaltered by detergent extraction. Residual desmosomes, as can be seen in thin sections, were also well- preserved. The skeletal framework was visualized in three dimensions as an unembedded whole mount that revealed the filament networks that were masked in Epon-embedded thin sections of the same preparation. The topography of cytoskeletal filaments was relatively constant throughout the epithelial sheet, particularly across intercellular borders. This ordering of epithelial skeletal filaments across contiguous cell boundaries was in sharp contrast to the more independent organization of networks in autonomous cells such as fibroblasts. Further extraction removed the proteins of the salt-labile cytoskeleton and the chromatin as separate fractions, and left the nuclear matrix-intermediate filament (NM-IF) scaffold. The NM-IF contained only 5% of total cellular protein, but whole mount transmission electron microscopy and immunofluorescence showed that this scaffold was organized as in the intact epithelium. Immunoblots demonstrate that vimentin, cytokeratins, desmosomal proteins, and a 52,000-mol-wt nuclear matrix protein were found almost exclusively in the NM-IF scaffold. Vimentin was largely perinuclear while the cytokeratins were localized at the cell borders. The 52,000-mol-wt nuclear matrix protein was confined to the chromatin- depleted matrix and the desmosomal proteins were observed in punctate polygonal arrays at intercellular junctions. The filaments of the NM-IF were seen to be interconnected, via the desmosomes, over the entire epithelial colony. The differentiated epithelial morphology was reflected in both the cytoskeletal framework and the NM-IF scaffold. 相似文献
15.
A.S.C. Wan T.L. Ngiam S.L. Leung M.L. Go P.W.S. Heng P.N. Natarajan A. Shafiee M. Vossoghi F. Savabi C.G. Francisco R. Freire R. Hernandez J.A. Salazar E. Suarez G.A.Garcia De La Mora Y.Grillasca R. O. Jimeno 《Steroids》1983,41(3):309-320
The synthesis of esters of norethisterone (17α-ethynyl-17β-hydroxy-estr-4-en-3-one) with acids containing a benzene ring is described, two methods of esterification being compared in terms of yield and convenience. The activities of these esters as long-acting contraceptive agents have been evaluated. 相似文献
16.
The chemosterilant metepa, administered orally and topically to adult M. domestica, was found to reduce aliesterase activity, to reduce the hatch of eggs, and when administered orally it also prolonged the pre-ovipositional period. Orally administered DDT had little effect on aliesterase but did reduce egg viability. Selection of a strain of M. domestica with diazinon, in an attempt to increase its resistance to diazinon, had the unexpected result of the flies becoming more susceptible but concomitantly their level of aliesterase was significantly increased. The aliesterase level of the immature stages of M. domestica is reported.
Zusammenfassung Es wurde festgestellt, daß das Chemosterilisans Metepa bei oraler oder topischer Applikation bei erwachsenen Stubenfliegen die Aliesterase-Aktivität herabsetzt, die Schlüpfrate der Eier vermindert und bei oraler Anwendung auch die Präovipositionszeit verlängert. Oral verabreichtes DDT hat wenig Einfluß auf die Aliesterase, setzt aber die Lebensfähigkeit der Eier herab. Die Selektion einer Linie von Musca domestica durch Diazinon mit dem Ziel, ihre Resistenz gegen Diazinon zu erhöhen, hatte das unerwartete Ergebnis, daß die Fliegen empfindlicher wurden, zugleich aber ihr Aliesterase-Spiegel signifikant anstieg. Der Aliesterase-Spiegel der nicht erwachsenen Stubenfliegen-Stadien wird angegeben.相似文献
17.
<正> 抗菌免疫核糖核酸(iRNA)已用于条件致病菌感染的临床治疗,并对其免疫活性做了全面的研究。现已证实iRNA能够诱导特异性抗体的产生和传递特异性的细胞免疫,并能诱生干扰素和白细胞间素Ⅰ、Ⅱ等淋巴因子和单核因子。但制备的iRNA是含有多种RNA种类的混合物,为明确各组份的免疫学功能,我们对iRNA进行了分离,并测定不同组份的免疫活性。 相似文献
18.
M Stemler T Weimer Z X Tu D F Wan M Levrero C Jung G R Pape H Will 《Journal of virology》1990,64(6):2802-2809
The immune response to the X protein of human hepatitis B virus (HBV) was studied by epitope mapping by using a set of MS2-HBx fusion proteins and synthetic peptides. Antibodies in sera of patients with acute and chronic HBV infection showed a multispecific immune response. Each serum contained antibodies to a different set of epitopes, which taken together cover most of the HBx sequence. Some of the epitopes were detectable only by immunoblotting with fusion proteins; others were detectable only by an enzyme-linked immunosorbent assay (ELISA) with synthetic peptides. The carboxy-terminal half of the HBx protein was preferentially recognized by antibodies from patients with chronic hepatitis and contained a short immunodominant antigenic region with at least two major nonoverlapping epitopes. Anti-HBx antibody titers as revealed by peptide ELISAs were highest and most frequent in patients with chronic hepatitis and usually low in acutely infected patients and asymptomatic carriers. The data demonstrate a remarkable qualitative and quantitative heterogeneity of the humoral HBx immune response which can be monitored by HBx-specific peptide ELISAs. Such tests may become useful diagnostic tools. 相似文献
19.
Two new loci for hybrid sterility in cultivated rice (Oryza sativa L.) 总被引:17,自引:0,他引:17
J. Wan Y. Yamaguchi H. Kato H. Ikehashi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(2):183-190
Female gamete abortion in Indica-Japonica crosses of rice was earlier identified to be due to an allelic interaction at the S-5 locus on chromosome 6. Recently, in other crosses of rice, similar allelic interactions were found at loci designated as S-7 and S-8, located on chromosomes 7 and 6 respectively. All of them are independent of each other. At the S-5 locus, Indica and Japonica rice have S-5
i
and S-5
j
alleles respectively and Javanicas, such as Ketan Nangka, have a neutral allele S-5
n
.The S-5
i
/S-5
j
genotype is semi-sterile due to partial abortion of female gametes carrying S-5
j
, but both the S-5
n
/S-5
i
and S-5
n
/S-5
j
genotypes are fertile. The S-5
n
allele is thus a wide-compatibility gene (WCG), and parents homozygous for this allele are called wide-compatible varieties (WCV). Such parents when crossed with Indica or Japonica varieties do not show F1 hybrid sterility. Wide-compatible parents have been used to overcome sterility barriers in crosses between Indica and Japonica rice. However, a Javanica variety, Ketan Nangka (WCV), showed typical hybrid sterility when crossed to the Indian varieties N22 and Jaya. Further, Dular, another WCV from India, showed typical hybrid sterility when crossed to an IRRI line, IR2061-628-1-6-4-3(IR2061-628). By genetic analyses using isozyme markers, a new locus causing hybrid sterility in crosses between Ketan Nangka and the Indicas was located near isozyme loci Est-1 and Mal-1 on chromosome 4, and was designated as S-9. Another new locus for hybrid sterility in the crosses between Dular and the IR2061-628 was identified and was found linked to four isozyme loci, Sdh-1, Pox-2, Acp-1 and Acp-2, on chromosome 12. It was designated as S-15. On the basis of allelic interactions causing female-gamete abortion, two alleles were found at S-9, S-9
kn
in Ketan Nangka and S-9
i
in N22 and Jaya. In the heterozygote, S-9
kn
/S-9
i
, which was semisterile, female gametes carrying S-9
kn
were aborted. The hybrid of Dular and IR2061-628, with a genetic constitution of S-15
Du
/S-15
i
, was semi-sterile and the female gametes carrying S-15
Du
were aborted. A Japonica tester variety, Akihikari, and an Indica variety, IR36, were found to have neutral alleles, S-9
nand S-15
n, at these loci, in addition to S-7
nand at S-7. The accumulation of three neutral alleles into a breeding line should help solve the hybrid sterility problem in wide crosses of rice. 相似文献
20.
棉铃虫致病菌BT—931菌株的应用研究 总被引:1,自引:0,他引:1
1992-1993年,作者从菏泽、聊城棉田采集的自然罹病死亡棉铃虫幼虫体内,分离到2个较高毒效的Bt菌株,编号为BT—931和BT—021,经室内毒力测定和田间药效试验表明,防效及保蕾效果接近或超过化学农药,菌药混剂3—5天平均防治效果达87.0-91.6%,增效作用显著。经1994年大田防治示范表明,利用BT—931菌剂。配合化学农药防治棉铃虫,具有成本低、保护天敌、持效期长、增产效益高等优点。本研究对菌剂的田间应用技术进行了试验示范。 相似文献