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31.
Hiroto Yoshikawa Monique N. Mayer Kathleen A. Linn Ryan M. Dickinson Anthony P. Carr 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(9):877-879
An 8-year-old, castrated male golden retriever was referred for lethargy and inappetance. Severe pain was elicited on palpation of the left temporomandibular joint region. Computed tomography revealed aggressive bone destruction of the left bulla. Squamous cell carcinoma was diagnosed. Malignant tumor in the canine middle ear is rare. 相似文献
32.
Masursky H Batson RM McCauley JF Soderblom LA Wildey RL Carr MH Milton DJ Wilhelms DE Smith BA Kirby TB Robinson JC Leovy CB Briggs GA Duxbury TC Acton CH Murray BC Cutts JA Sharp RP Smith S Leighton RB Sagan C Veverka J Noland M Lederberg J Levinthal E Pollack JB Moore JT Hartmann WK Shipley EN De Vaucouleurs G Davies ME 《Science (New York, N.Y.)》1972,175(4019):294-305
At orbit insertion on 14 November 1971 the Martian surface was largely obscured by a dust haze with an extinction optical depth that ranged from near unity in the south polar region to probably greater than 2 over most of the planet. The only features clearly visible were the south polar cap, one dark, spot in Nix Olympica, and three dark spots in the Tharsis region. During the third week the atmosphere began to clear and surface visibility improved, but contrasts remained a fraction of their normal value. Each of the dark spots that apparently protrude through most of the dust-filled atmosphere has a crater or crater complex in its center. The craters are rimless and have featureless floors that, in the crater complexes, are at different levels. The largest crater within the southernmost spot is approximately 100 kilometers wide. The craters apparently were formed by subsidence and resemble terrestrial calderas. The south polar cap has a regular margin, suggsting very flat topography. Two craters outside the cap have frost on their floors; an apparent crater rim within the cap is frost free, indicating preferentia loss of frost from elevated ground. If this is so then the curvilinear streaks, which were frost covered in 1969 and are now clear of frost, may be low-relief ridges. Closeup pictures of Phobos and Deimos show that Phobos is about 25 +/-5 by 21 +/-1 kilometers and Deimos is about 13.5 +/- 2 by 12.0 +/-0.5 kilometers. Both have irregular shapes and are highly cratered, with some craters showing raised rims. The satellites are dark objects with geometric albedos of 0.05. 相似文献
33.
兰州大尾羊心脏型脂肪酸结合蛋白(H-FABP) 基因克隆及其同源性比较 总被引:1,自引:1,他引:1
【目的】克隆兰州大尾羊心脏型肪酸结合蛋白(H-FABP)基因全长cDNA序列,为研究绵羊H-FABP生物学作用和生产应用提供理论依据。【方法】根据已知哺乳动物H-FABP基因 cDNA 序列,设计5''和3''特异引物,运用cDNA 末端快速扩增(RACE)技术获得兰州大尾羊H-FABP基因全长 cDNA 序列。【结果】 扩增获得兰州大尾羊5''端425 bp、3''端231 bp片段和 177 bp中间片段,拼接获得748 bp兰州大尾羊H-FABP基因全长cDNA 序列(GenBank登录号:JQ780322)。 兰州大尾羊H-FABP基因ORF长 402 bp,编码 133 个氨基酸。核苷酸序列分析显示兰州大尾羊H-FABP基因序列与大多数哺乳动物相似,但其第66位发生的碱基转换(T←→G)引起所编码的第22位天门冬氨酸(N)不同于其它所有物种的赖氨酸(K)。构建的基因进化树分析结果显示兰州大尾羊与山羊亲缘关系最近。预测兰州大尾羊H-FABP蛋白质的空间结构与山羊和牛H-FABP类似,由2个α螺旋和10个反向平行的β折叠组成,10 个折叠片围成一个桶状结构,疏水性残基位于桶内,用于结合脂肪酸。【结论】克隆了兰州大尾羊H-FABP基因,为进一步研究该基因的功能奠定了基础。 相似文献
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36.
Boutilier P Carr A Schulman RL 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(2):178-187
All leptospirosis microscopic agglutination test titers for the Leptospira serovars icterohaemorrhagiae, canicola, grippotyphosa, bratislava, hardjo, and pomona conducted on 1,260 blood samples from dogs at the University of Illinois Veterinary Diagnostic Laboratory between March 1996 and March 2001 were evaluated. Low titers (1:100 to 1:400) were predominantly L. icterohaemorrhagiae and L. canicola, which represented the predominant serovars (65.4%) among all positive samples with low titers. L. grippotyphosa was the predominant serovar (72.1%) among samples with clinically significant titers (greater than 1:800). The medical records of 87 dogs with a titer greater than 1:800 that were patients at the Veterinary Teaching Hospital of the University of Illinois were reviewed. A clinical diagnosis of leptospirosis was made in 15 cases (17.2%) based on the elevated titer, appropriate clinical signs, lack of recent vaccination, and lack of concurrent disease that could explain the clinical signs present. Renal disease was present in 10 of the cases, concurrent renal and hepatic disease in two, and hepatic disease in three. In 12 cases, the predominant serovar was L. grippotyphosa; titers to L. grippotyphosa and L. bratislava were equal in magnitude in three cases. 相似文献
37.
为了检测牛GDF-9基因mRNA在怀孕期牛生殖系统的表达情况,为GDF-9基因在雌性动物繁殖上的研究提供一定的理论依据。本试验根据GenBank中报道的牛GDF-9基因序列设计引物,从牛卵巢、输卵管、子宫、肾脏中提取RNA,采用RT-PCR技术进行cDNA扩增,扩增产物与载体pGM-T连接,转化大肠杆菌DH5α,筛选阳性克隆,测序。结果表明,已成功克隆的阳性重组子经测序鉴定其片段大小与预期大小完全一致,为264 bp。序列同源性分析比较表明,该cDNA及其推导的氨基酸序列与绵羊GDF-9cDNA和氨基酸序列同源性分别为97%和94%。以-βactin为内参照物,采用RT-PCR技术进行半定量分析,通过检测比较牛GDF-9基因在卵巢、输卵管、子宫、肾脏组织中mRNA的表达情况。结果表明,牛GDF-9基因在卵巢中表达量最高,在输卵管、子宫、肾脏中均有表达,但表达量不高。 相似文献
38.
Concentrations of benomyl greater than 10 ng ml?1 inhibited germination and hyphal growth of the vesicular-arbuscular mycorrhizal fungus Glomus caledonicum on water agar. This effect was attributable to only the activity of methyl-2-benzimidazole carbamate, one of the two hydrolysis products of benomyl. Hyphal growth but not germination was affected by the pH of water agar buffered with 10 mm 2-(N-morpholino)ethane sulphonic acid. 相似文献
39.
Jen JC Chan WM Bosley TM Wan J Carr JR Rüb U Shattuck D Salamon G Kudo LC Ou J Lin DD Salih MA Kansu T Al Dhalaan H Al Zayed Z MacDonald DB Stigsby B Plaitakis A Dretakis EK Gottlob I Pieh C Traboulsi EI Wang Q Wang L Andrews C Yamada K Demer JL Karim S Alger JR Geschwind DH Deller T Sicotte NL Nelson SF Baloh RW Engle EC 《Science (New York, N.Y.)》2004,304(5676):1509-1513
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing. 相似文献
40.
披针叶黄华生物碱成分研究 总被引:4,自引:0,他引:4
采用 GC- MS联用分析技术从披针叶黄华总生物碱中分离鉴定出 12个喹喏里西啶生物碱 ,即无叶豆碱 ,N-甲基金雀花碱 ,金雀花碱 ,白羽扇豆碱 ,黄华碱 ,臭豆碱 ,N-甲醛基金雀花碱 ,Dodecahydro- 7,14 -methanodipyrido[1,2 - a:1′,2′- E][1.5 ]diazocine,Pyridine1- acetyl- 1,2 ,3,4 - tetrahydro- 5 - (2 - piperdinyl) ,7,14 -Methano- 2 H,6 H- dipyrido[1,2 - a:1′,2′- e][1,5 ]diaz,1,1- Dim ethyl- 3- (2 - nitrophenyl) ,7,14 - Methano- 4 H,6 H-dipyrido[1,2 - a:1′,2′- e][1,5 ]diaz。后 5种化合物为首次从该植物中鉴定 相似文献