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51.
分析结果表明①2种观测系统的测量结果的误差同多伦多市与SAGEⅡ观测点的纬度差异有很大的关系;②2种观测系统的测量结果均显示,多伦多地区臭氧极大层的臭氧含量与臭氧极大层出现的高度有明显的季节变化特征,这与对流层顶的季节变化一致,且臭氧极大值与极大层出现的高度之间大致存在反相关关系;③1994~1995年期间,由2种观测系统的测量结果计算出的10~45*!km的平均气柱臭氧量分别为254和275*!Du(1Du=0.01*!mm),两者间的相对误差大约为-10%.  相似文献   
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D B Gower  S Bird  P Sharma  F R House 《Experientia》1985,41(9):1134-1136
Axillary 5 alpha-androst-16-en-3-one (5 alpha-androstenone) levels were found to be significantly higher in men than in women but do not vary between left and right axillae, are not related to age, handedness or degree of hirsutism (in women) nor to anosmia to this steroid. In men (but not in women), levels are related linearly to axillary cholesterol concentrations but not to squalene. Olfactory thresholds for 5 alpha-androstenone varied widely, the lowest recorded being 0.2 ppb, but there was no difference in thresholds between men and women. Women (70%) found the smell 'repellant' but anosmia did not differ greatly between men and women (9-20%). Anosmia to the smell of 5 alpha-androst-16-en-3 alpha-ol was most marked in women (90%) rather than in men (45%). Axillary 5 alpha-androstenone values were generally consistent with the 'musky' or 'strong' smells of male axillary extracts, compared with the 'sweet' smell of those from female subjects.  相似文献   
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Zusammenfassung Mit Präzipitationsversuchen im Agargel wird gezeigt, dass Präzipitine ausRicinus communis-oderAbrus precatorius-Samen und die spezifischen Anti-PnXIV-Präzipitine des Pferdeserums mit verschiedenen Seitenästen der Strukturformel von PnXIV-Kapselpolysaccharid reagieren können.  相似文献   
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B Hendrich  U Hardeland  H H Ng  J Jiricny  A Bird 《Nature》1999,401(6750):301-304
In addition to its well-documented effects on gene silencing, cytosine methylation is a prominent cause of mutations. In humans, the mutation rate from 5-methylcytosine (m5C) to thymine (T) is 10-50-fold higher than other transitions and the methylated sequence CpG is consequently under-represented. Over one-third of germline point mutations associated with human genetic disease and many somatic mutations leading to cancer involve loss of CpG. The primary cause of mutability appears to be hydrolytic deamination. Cytosine deamination produces mismatched uracil (U), which can be removed by uracil glycosylase, whereas m5C deamination generates a G x T mispair that cannot be processed by this enzyme. Correction of m5CpG x TpG mismatches may instead be initiated by the thymine DNA glycosylase, TDG. Here we show that MBD4, an unrelated mammalian protein that contains a methyl-CpG binding domain, can also efficiently remove thymine or uracil from a mismatches CpG site in vitro. Furthermore, the methyl-CpG binding domain of MBD4 binds preferentially to m5CpG x TpG mismatches-the primary product of deamination at methyl-CpG. The combined specificities of binding and catalysis indicate that this enzyme may function to minimize mutation at methyl-CpG.  相似文献   
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Mutations in SEPT9 cause hereditary neuralgic amyotrophy   总被引:7,自引:0,他引:7  
Hereditary neuralgic amyotrophy (HNA) is an autosomal dominant recurrent neuropathy affecting the brachial plexus. HNA is triggered by environmental factors such as infection or parturition. We report three mutations in the gene septin 9 (SEPT9) in six families with HNA linked to chromosome 17q25. HNA is the first monogenetic disease caused by mutations in a gene of the septin family. Septins are implicated in formation of the cytoskeleton, cell division and tumorigenesis.  相似文献   
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Two akanthophoreid taxa, Chauliopleona and the new genus Saurotipleona, are modest contributors to tanaidacean diversity in the benthos of seas from Iceland to the British Isles along the ‘Atlantic Margin’. Three of H.J. Hansen’s ‘Ingolf’ species, originally within the genus Leptognathia, are rediagnosed, i.e. Chauliopleona amdrupii, C. armata and C. hastata. One new species, C. bamberi, from British waters is described and a new genus and species, Saurotipleona julii, is described from bathyal depths in the Irminger and Iceland basins. The latter is similar to Chauliopleona in having a sternal spur on pleonite-5 but this is of a slightly different form and is ventrally directed; it also has two superodistal spines on the propodus of pereopod-5, a distinctly plesiomorphic character in the family. A distribution map and key to the identification of these species are given.

http://zoobank.org/urn:lsid:zoobank.org:pub:E7EF8C72-D1C6-438E-B9C2-A5CE637FB75A  相似文献   
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