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891.
Stephen Gibbs Research Assistant David H. Teeter 《Ocean Development & International Law》2013,44(1):103-162
Marine Transportation in the North Pacific 相似文献
892.
893.
Brompton Hospital/Medical Research Council Collaborative Trial 《BMJ (Clinical research ed.)》1972,4(5837):383-388
The results are reported here of a long-term double-blind controlled clinical trial of disodium cromoglycate (D.S.C.G.) and isoprenaline, D.S.C.G. alone, isoprenaline alone, and a placebo given as a powder for inhalation in the treatment of severe bronchial asthma.At the end of one year 16 out of 20 patients on D.S.C.G.-isoprenaline remained on the allocated capsules, compared with 10 out of 15 on D.S.C.G., 5 out of 20 on isoprenaline, and 3 out of 19 taking the placebo. The differences between each of the D.S.C.G.-isoprenaline and D.S.C.G. regimens compared with the isoprenaline and placebo regimens were statistically significant. After eight weeks on four capsules a day the patients in each group were allocated at random so that half continued on full dosage and half on a reducing regimen. At the end of the year there was no significant difference in the failure rate between patients allocated the full dosage and the patients on the reducing dosage. The capsules were well tolerated and toxicity to D.S.C.G. was not observed. 相似文献
894.
本文记述镰尾姬蜂属Grypocentrus Ruthe一新种:卡镰尾姬蜂Grypocentrus kasparyani sp.nov.本种与室镰尾姬蜂G.areolaris Kasparyan相似,以下特征可与后者区别:唇基宽为长的2.7-3.0倍:眼颚距为上颚基部宽的0.10-0.15倍;触角鞭节16-18节(绝大多数为17节);卵柄较长也较细。正模,1991-06-09;配模,1993-05-30;副模:1,1991-06-09,2,2,1993-05-30;辽宁沈阳,盛茂领采。 相似文献
895.
896.
Kunio WATANABE 《动物学报》2010,56(2)
Hand preference of wild moor monkeys Macaca maurus was investigated in food reaching situations at the Karaenta Nature Reserve, South Sulawesi, Indonesia. The frequency picking up sweet-corn grains to take into the mouth by either hand of monkeys was counted directly at the feeding ground where sweet-corn grains were scattered for monkeys. Among the 20 monkeys examined, 8 were fight-handed, 8 were left-handed, and 4 were ambilateral. The results indicated the prevailed hand preference on individual level but not either trends of left- or right-hand preference on population level. The trend toward a higher proportion of left-handed monkeys found in Japanese and rhesus monkeys was not found. Some other characteristics found in moor monkeys are discussed in comparison with those previous findings in Japanese and Tibetan macaques in order to evaluate variations within the genus Macaca. 相似文献
897.
M. J. Carrier M. E. Nugent W. C. A. Tacon S. B. Primrose Director of Microbiology Process Research 《Trends in biotechnology》1983,1(4):109-113
Using recombinant DNA technology it is relatively easy to construct strains of bacteria which over-produce foreign proteins such as those from human, animal or viral sources. In the near future the same methodology will be used to increase the production of natural products of microorganism by manipulating metabolic pathways, e.g. those involved in antibiotic or amino acid syntheses. This article reviews the factors which lead to over-expression of proteins in E. coli and the possible consequences when large scale culture is undertaken. 相似文献
898.
Muthukumarasamy Uthayakumar Bowdadu Benazir Sanjeev Patra Marthandan Kirti Vaishnavi Manickam Gurusaran Kanagarajan Sureka Jeyaraman Jeyakanthan Kanagaraj Sekar 《基因组蛋白质组与生物信息学报(英文版)》2012,10(4):217-225
Analysis of protein sequences from Mycobacterium tuberculosis H37Rv(Mtb H37Rv) was performed to identify homopeptide repeatcontaining proteins(HRCPs).Functional annotation of the HRCPs showed that they are preferentially involved in cellular metabolism.Furthermore,these homopeptide repeats might play some specific roles in protein-protein interaction.Repeat length differences among Bacteria,Archaea and Eukaryotes were calculated in order to identify the conservation of the repeats in these divergent kingdoms.From the results,it was evident that these repeats have a higher degree of conservation in Bacteria and Archaea than in Eukaryotes.In addition,there seems to be a direct correlation between the repeat length difference and the degree of divergence between the species.Our study supports the hypothesis that the presence of homopeptide repeats influences the rate of evolution of the protein sequences in which they are embedded.Thus,homopeptide repeat may have structural,functional and evolutionary implications on proteins. 相似文献
899.
900.
本文指出传统CT图像存在的缺陷及不足之处;介绍新一代高、低压滑环及螺旋CT实现快速连续扫描的原理和优越性,便于了解其基本知识。 相似文献