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91.
92.
应用低严格度—单引物聚合酶链反应对问号钩体中国参考株的… 总被引:1,自引:0,他引:1
G1、G2引物是对问号钩体具有特异性引物。分别用G1或G2单引物对问号钩体中国参考株进行前4个低严格度循环的PCR扩增,扩增带谱显示赖型、犬型、致热型、秋季型、澳洲型、临海型、乌尔夫型、溶血型为一类,而爪哇型、拜伦型、波摩那型、七日热型、巴叶赞型塔拉索夫型、曼耗Ⅱ型是不与以上赖型等血清型本为一类,双曲钩体atoc型及伊利尼细丝体伊利尼型的扩增带谱与问号钩体截然不同。应用苯酚法提取的高纯度钩体DNA 相似文献
93.
The sequence of rat hypothalamic pro-thyrotropin releasing hormone, deduced by sequencing of cDNA, in addition to 5 TRH progenitor genitor sequences contains leader, trailer and 4 intervening sequences separated by paired basic amino acid sequences. We have developed radioimmunoassays to synthetic peptides corresponding to portions of these cryptic proTRH sequences and have used these assays to identify and partially characterize proTRH peptides, distinct from TRH, in extracts of rat brain. Two of these peptides correspond closely in size to one intervening sequence and the car☐y-terminal sequence of proTRH. Three other peptides correspond to the intact amino-terminal leader sequence and two peptides formed by a further cleavage of the leader sequence at an internal paired basic amino acid sequence. 相似文献
94.
精神病混合家系GRIK2基因多态性的关联研究 总被引:2,自引:2,他引:0
目的 在中国汉族人群混合家系中探讨GRIK2基因多态性与精神分裂症、心境障碍是否 关联。方法 采用PCR RFLP技术对GRIK2基因多态性rs6922753(T/C)和rs2227283(G/A)分型,进行 传递不平衡检验(TDT)。结果 (1)rs6922753多态性与精神分裂症(χ2=3.13,P>0.05)或心境障碍 (χ2=3.20,P>0.05)无关联,但在发病年龄≤25岁的患者中与两组疾病均相关联(P<0.05);(2) rs2227283多态性与精神分裂症(χ2=9.85,P<0.01)、心境障碍(χ2=13.50,P<0.01)呈显著关联;(3) 双位点TDT提示单体型TG、CA与精神分裂症、心境障碍相关联(P<0.05)。结论 在中国汉族人群 中GRIK2基因或邻近基因可能是精神分裂症和心境障碍的共同易患基因之一,并可能影响发病年龄。 相似文献
95.
皮肤交界性平滑肌瘤的复发与恶性转化 总被引:3,自引:0,他引:3
目的探讨皮肤交界性平滑肌瘤的复发与恶性转化。方法复习2例皮肤交界性平滑肌瘤及其复发恶性转化的临床病理特征、免疫组化表型及相关文献。结果2例病变位于下肢和额部,肉瘤组织平滑肌标记阳性。结论少数病理诊断为皮肤平滑肌瘤的病例,虽然浅表且组织形态良性,但其生物学恶性潜能尚不能确定,部分病例复发后可转变为典型的平滑肌肉瘤。 相似文献
96.
Dr. Yen-Chun Lin MD Jiahn-Shing Lee MD Shiu-Chen Wu MD Ling-Yuh Kao MD Chia-Yun Li MD Ken-Kuo Lin MD 《Annals of Ophthalmology》2003,35(1):19-24
This study analyzed the feasibility of fitting keratoconus-affected corneas with nonkeratoconus rigid gas-permeable (RGP)
contact lenses. We retrospectively studied patients with a diagnosis of keratoconus in the past 10 years who were fitted successfully
with nonkeratoconus RGP lenses by the same physician. Results confirmed nonkeratoconus RGP lenses as the first-line correction
tool. Additionally, we found a simple equation to speed the choice of the base curves of the lenses.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. 相似文献
97.
Chuan-ling Qiao Kang-zhen Yu Yong-ping Jiang Yong-qing Jia Guo-bin Tian Ming Liu 《Avian pathology》2003,32(1):25-31
Inactivated whole avian influenza virus (AIV) vaccine provides protection against homologous haemagglutinin (HA) subtype virus, but poor protection against a heterologous HA virus. Moreover, it induces chickens to produce antibodies to cross-reactive antigens, especially nucleoprotein, which is limits AIV serological surveillance. In this study, a recombinant fowlpox virus co-expressing HA (H5 subtype) and NA (N1 subtype) genes of AIV was evaluated for its ability to protect chickens against intramuscular challenge with a lethal dose of highly pathogenic (HP) AIV. Susceptible chickens were also vaccinated by wing-web puncture with the parent fowlpox vaccine virus. Following challenge 4 weeks later with HPAIV, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with either the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 100% mortality following challenge. This protection was accompanied by the high levels of specific antibody to the respective components of the recombinant vaccine. The above results showed that rFPV-HA-NA could be a potential vaccine to replace current inactivated vaccines for preventing AI. 相似文献
98.
99.
Cell type-specific gene expression in the neuroendocrine system. A neuroendocrine-specific regulatory element in the promoter of chromogranin A, a ubiquitous secretory granule core protein. 总被引:5,自引:1,他引:4 下载免费PDF全文
H Wu D J Rozansky N J Webster D T O'Connor 《The Journal of clinical investigation》1994,94(1):118-129
100.
Islet amyloid polypeptide (IAPP) has been recently identified as the principal constituent of amyloid deposits in pancreatic islets of patients with type 2 (non-insulin-dependent) diabetes mellitus and causes insulin resistance in some target cells. In addition, glucose-induced insulin secretion is inhibited by IAPP. We studied the effect of IAPP on proinsulin biosynthesis in rat insulinoma (RINr) cells. Glucose at concentrations of 0, 15, 30, 60, 100, and 300 mg/dl stimulated proinsulin biosynthesis in a dose-responsive and and actino-mycin D-inhibitable manner after 6 h of incubation. At a glucose concentration of 300 mg/dl, IAPP decreased the mean responses of proinsulin biosynthesis to 61.2 and 29% at concentrations of 0.1 and 1 microM, respectively, compared with the IAPP-free control. In conclusion, IAPP inhibits glucose-induced proinsulin biosynthesis in RINr cells. IAPP might play an important role in the pathogenesis of type 2 diabetes mellitus. 相似文献