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21.
Sarcomas were induced in Fl mice between C57BL/6N and C3H/He strains by subcutaneous injection of methylcholanthrene. The c-myc oncogene was found to be amplified in 16 cases among 43 sarcomas of C57BL/6N × C3H/He mice and 1 case among 5 sarcomas of the reciprocal cross. The origin of the amplified allele was determined by the polymerase chain reaction single strand conformation polymorphism analysis. Among the 17 sarcomas, only one had both of the alleles amplified. The rest of the tumors carried the amplified c-myc allele coming either from C57BL/6N (9 cases) or from C3H/He (8 cases). These results indicate that the c-myc allele is amplified randomly in methylcholanthrene-induced mouse sarcomas irrespective of its origin, such as paternal or maternal allele and C57BL/6N or C3H/He allele. In addition to these changes, the unamplified c-myc oncogene was found to be lost in 12 cases out of the 17 sarcomas with the amplification. 相似文献
22.
新型饮水对小鼠繁殖及抗氧化酶活性的影响 总被引:11,自引:0,他引:11
目的 探讨新型饮水对健康的影响及其保健作用。方法 将矿溶生态水、活化水、纯净水、矿泉水、碱性离子水等 5种新型饮水作为唯一水源分别喂饲亲代及子代小鼠 3个月 ,对照给予天然水。观察它们对小鼠体重、繁殖及抗氧化酶活性的影响。结果 与天然水比较 ,活化水、矿溶生态水促进亲代雄性小鼠体重增长 (P <0 0 5) ;矿溶生态水使子代小鼠、矿泉水和碱性离子水使子代雄性小鼠体重增长缓慢 (P <0 0 5) ;纯净水使新生仔鼠体重减轻 (P <0 0 5) ,活化水、矿溶生态水使小鼠窝产仔数增多 (P <0 0 5) ,5种水对小鼠受孕率、妊娠率、出生存活率无影响 ;矿溶生态水、活化水、纯净水、矿泉水使小鼠肝组织SOD活力升高 (P <0 0 5) ,碱性离子水使肝组织SOD活力降低 (P <0 0 5)。结论 5种新型饮水对小鼠体重有影响 ,对受孕率、妊娠率、出生存活率无影响 ;矿溶生态水、活化水、纯净水、矿泉水有提高SOD活力作用 相似文献
23.
沈备娟 《浙江中医药大学学报》2007,31(4):519-519,522
在青年学生中吸收优秀分子已成为高校党组织发展工作的重要组成部分,最近几年来,高中党建工作也不断发展。了解青年学生党建现状,更好地利用中学党建工作成果,提出了做好衔接工作的现实意义及对策措施。 相似文献
24.
作者对湖北神农架地区民间流传的72“还阳”药深入调查,采集标本,总结报道了其功效、用法及种类,共有56种,属22科,其中有10种为新药物资源。药源极丰富,为开发利用提供了依据。 相似文献
25.
师德师风是评价教师队伍素质的第一标准。党的十八大以来,习近平总书记对高校师德师风建设作出一系列重要指示,亲自部署谋划师德师风建设。当前,高校师德师风建设的整体态势是积极良好的,但仍面临协同管理机制有待进一步完善、教师育人意识有待进一步提高、师德培训成效有待进一步深化、评价考核体系有待进一步健全等问题。站在新的历史方位上,高校需着眼于新形势新情况,从构建师德师风建设运行体系、健全师德师风建设引领体系、健全师德师风建设考核体系、打造师德师风建设关怀体系等向度,进一步深化新时代师德师风建设,全面提升高校教师师德水平。 相似文献
26.
Murasaki Mitsukuni Miura Sadanori 《Progress in neuro-psychopharmacology & biological psychiatry》1992,16(6)
Mitsukuni Murasaki and Sadanori Miura: The Future of 5-HT1A Receptor Agonists. (Aryl-Piperazine Derivatives) Prog. Neuro- Psychopharmacol-& Biol Psychiat, 1992, 16(6): 833–845.
- 1. 1. At present the dominant position among anti-anxiety medications has changed from meprobamate to the benzodiazepine derivatives.
- 2. 2. In order to avoid benzodiazepine's (BZ) undesirable side effects such as impairment of psycho-motor function, memory impairment, low dose dependence and withdrawal symptoms, a third generation anxiolytic agent, buspirone, the focus of the aryl-piperazine group of anti-anxiety agents, has been introduced recently.
- 3. 3. Aryl-piperazine derivatives work as 5-HT1A receptor partial agonists and are known as serotonin normalizers.
- 4. 4. Therefore, they are expected to have not only an anxiolytic function but also an anti-depressant effect as well.
- 5. 5. A characteristic of the aryl-piperazine derivatives is that they have no sedative and muscle relaxant effects, and they do not have BZ's undesirable side-effects, especially in regard to withdrawal symptoms. However they have a rather weak anxiolytic action and a slow onset of action.
- 6. 6. Aryl-piperazine derivatives will not take the place of BZ, but the use of BZ and buspirone as bridge medications, making the most of the strong points of both, can be proposed as a way to compensate for their respective disadvantages.
Keywords: aryl-piperazine derivatives; future of new anxiolytics; 5-HT1A receptor agonist; nonbenzodiazepine anxiolytic 相似文献
27.
R. Pontoriero J. Lindhe S. Nyman T. Karring E. Rosenberg F. Sanavi 《Journal of clinical periodontology》1989,16(3):170-174
The present investigation was designed to evaluate the regenerative potential of the periodontal tissues in degree III furcation defects at mandibular molars using a treatment procedure based on the principle of guided tissue regeneration. The patient sample included 21 patients, 26-65 years of age, who presented periodontal lesions in the right and left molar regions including "through and through" furcation defects. After an initial examination, each patient was subjected to a series of full-mouth scaling and root planing. 2-3 months later, they were recalled for a baseline examination. The furcation-involved molars were randomly assigned in each patient to either a test or a control treatment procedure. The test procedure included the elevation of muco-periosteal flaps at the buccal and lingual aspects of the molars. Granulation tissue was removed and the exposed root surfaces were debrided and planed. The width and the height of the entrance openings to the furcation defects were assessed. A teflon membrane was adjusted to cover the entrances to the defects (buccal and lingual) and was retained in the manner described by Pontoriero et al. (1988). The flaps were repositioned on the outer surface of the membrane and secured by sutures which were removed after 10 days. Following surgery, the patients were instructed to rinse the mouth twice daily for 4 weeks with chlorhexidine gluconate. The membranes were removed after a healing period of 1-2 months. A surgical procedure identical to the test procedure was performed in the control tooth regions with the exception of the placement of membranes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
28.
Elongation of the cytoplasmic domain,due to a point deletion at exon 7, results in an HLA-C null allele,Cw*0409 N 总被引:2,自引:0,他引:2
Balas A Santos S Aviles MJ García-Sánchez F Lillo R Alvarez A Villar-Guimerans LM Vicario JL 《Tissue antigens》2002,59(2):95-100
The development of molecular techniques for HLA typing has allowed the identification of genes previously assigned as serologic blank alleles. Lack or poor cell surface expression has been found for molecules coded by HLA-A, -B, -DRB4, -DRB5, and -DPB1 genes. In this report we describe the first HLA-C gene encoding for a null cell surface molecule. HLA-Cw*0409 N shows a point deletion at position 1095 within exon 7. This mutation provokes a codon reading shift, generating a new translation stop codon 97 bp downstream to that described in alleles normally expressed. This new stop codon location implies the presence of 32 extra amino acid residues in the cytoplasmic domain. Transfection experiments suggest that elongation of the cytoplasmic domain in Cw*0409 N would be the cause of cell surface expression failure, although Cw*0409 N heavy chain is able to create stable complexes with beta2-microglobulin. HLA-C fragment length analysis in a small selected group of samples with B44-Cblk haplotypic associations allowed us to identify two additional subjects showing both a serologic silent Cw*04 allele and a point base deletion at the 3' end of the HLA-C gene. This finding indicates that the allele frequency of Cw*0409 N within serologic C blank alleles would be appreciable, although basically restricted to the (A23)-Cw*0409 N-B*4403-DR7-DQ2 haplotype. 相似文献
29.
Jacek Dabert Agnieszka Badek Maciej Skoracki 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(3):250-267
Two new genera and three new species of feather mites (Astigmata, Pterolichoidea, Analgoidea) are described from two closely
related species of cockatoos, Cacatua galerita (type host) and C. sulphurea (Psittaciformes, Cacatuidae): Astrolabelichus caudatus gen. nov., sp. nov. (Pterolichidae), Psittophagus lacunosus sp. nov. (Pterolichidae), and Cacatualges microdiscus gen. nov., sp. nov. (Xolalgidae). The presence of the same set of mite species on these two species of parrots points to
a very close affinity of Cacatua sulphurea and C. galerita and gives additional support for the recent hypothesis of the conspecificity of these birds. 相似文献
30.
华北地区汉族群体15个短串联重复序列基因座遗传多态性分析 总被引:2,自引:3,他引:2
目的调查华北地区汉族人群15个短串联重复序列(shorttandemrepeat,STR)基因座遗传多态性分布和群体遗传学数据。方法应用毛细管电泳技术和五色荧光复合扩增的方法,检测597名汉族无关个体的15个STR基因座基因型。结果15个STR基因座的基因频率分布均符合Hardy-Weinberg平衡,所检测的15个STR遗传标记均具有高度多态性,杂合度均超过0.62,15个基因座的个体识别力在0.802~0.967之间,非父排除率在0.320~0·697之间,匹配概率在0.033~0.198之间。15个基因座的累积个体识别能力为0.999999以上,累积非父排除率为0.99999571,累积匹配概率为8.93×10-18。结论联合检测15个基因座可为亲缘鉴定和个体识别提供可靠的法医学证据,这15个STR基因座适用于中国人群的法医物证学检验。 相似文献