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131.
John G. Frazier Harry L. Fierstine Sallie C. Beavers Federico Achaval Hiroyuki Suganuma Robert L. Pitman Yuichiro Yamaguchi Carlos Ma. Prigioni 《Environmental Biology of Fishes》1994,39(1):85-96
Synopsis Billfishes have long been known to impale a great variety of objects, but there are only two brief, obscure records of marine
turtles being speared. Details are presented on these two, as well as on two other confirmed records; data from two additional
unconfirmed records are also presented. In total, three species of marine turtles are known to have been impaled by three
species of billfishes; a fourth species of fish and a fourth species turtle are listed in an unconfirmed case. Records come
from the eastern and western Pacific as well as the eastern Atlantic. Of the four confirmed cases, the turtles survived in
two, and apparently died as an effect of the spearing in the other two. In three confirmed cases only the impaled rostrum
was encountered, and in one confirmed case the entire fish was found, with its rostrum piercing the turtle. There is no obvious
advantage — or clear disadvantage — involved in impaling turtles. It is argued that these attacks are accidental, and the
result of attempts made by the billfish to capture prey that are near the turtle. These spearings indicate that the chelonians
serve as shelters for prey animals on the high seas, and thus, are further evidence of the pelagic existence of marine turtles.
The impalings are evidence of a singular ecological role of the turtles — as live fish aggregation devices. 相似文献
132.
长江三峡库区种子植物的中国特有分布 总被引:13,自引:4,他引:9
报道了分布于长江三峡库区的中国种子植物特有属及特有植物在库区的水平与垂直分布概况,对库区的特有分布的特点也进行了简要的分析和探讨。 相似文献
133.
134.
Harry Schwartz Ralf-Erwin Licht Hans-Eckart Radunz 《Applied microbiology and biotechnology》1993,40(2-3):382-385
Eighteen filamentous fungi and six actinomycetes species were screened for their ability to metabolize bisoprolol, a \-blocking drug. All strains of Cunninghamella tested accumulated metabolite M4 = EMD 46193 ([4-(2-hydroxy-3-isopropylaminopropoxy)benzyloxy]ethanol). Among the strains investigated only Gliocladium deliquescens excreted the corresponding carbonic acid M1 = EMD 44025 into the culture medium. Biotransformation of bisoprolol by fungi occurred only during growth in complex medium or with resting cells after cultivation in complex medium. The screened Actinomycetes showed no biotransformation of the drug.
Correspondence to: H. Schwartz 相似文献
135.
Yong Soo Park Zhong Ping Shi Sumihisa Shiba Cayuela Chantal Shinji Iijima Takeshi Kobayashi 《Applied microbiology and biotechnology》1993,38(5):649-655
Fuzzy reasoning was applied to control both ethanol and glucose concentrations in fed-batch cultures of baker's yeast. This fuzzy controller consisted of three membership functions (concentrations of dissolved oxygen (DO), ethanol and glucose) and 18 production rules. Fuzzy inference was carried out by IF {A is a and B is b,...#x007D;, THEN {C is c} from the on-line measured concentrations of DO, ethanol and glucose. When medium concentrations of ethanol and glucose in fed-batch culture of baker's yeast were set at 2 g/l and 0.2 g/l, both ethanol and glucose concentrations were controlled at 2.67±0.35 g/l and 0.27±0.25 g/l, respectively, ethanol production was reduced from 26 g/l to 34 g/l, cell yield increased from 0.38 to 0.53 g dry cell/g consumed glucose and ethanol yield decreased from 0.50 to 0.14 g ethanol/g consumed glucose, respectively, as compared with those of the glucose only control at 0.2 g/l. 相似文献
136.
Mahmoud A. Hassan Harry Jan Swartz Gordon Inamine Phillip Mullineaux 《Plant Cell, Tissue and Organ Culture》1993,33(1):9-17
Experiments in shoot regeneration and virulentAgrobacterium tumefaciens-mediated transformation were used to develop a protocol forRubus transformation. This protocol was then used to produce transformedRubus plants fromin vitro internodes inoculated with anAgrobacterium tumefaciens encoding neomycin phosphotransferase on its disarmed T-DNA. Two transformed plants were selected from 800 inoculations on a medium containing 10 µg ml–1 kanamycin. Results indicated that this level of kanamycin successfully selected against non-transformed cells but did not reduce the number of transformed, kanamycin-resistant, shoots formed. Enzyme assays and Southern blot analysis verified the presence of the -glucuronidase gene in the plant genome. 相似文献
137.
Oscar J. M. Goddijn Paula M. van der Duyn Schouten Rob A. Schilperoort J. Harry C. Hoge 《Plant molecular biology》1993,21(5):907-912
A cDNA clone, pMA1949, detects two mRNA species in wheat seedling tissue that are late embryogenesis-abundant (LEA) and dehydration stress-inducible. Sequence analysis of the pMA1949 clone shows it to be a 991 bp partial cDNA encoding a polypeptide of 317 amino acids with homology to two group 3 LEA proteins, carrot (DC8) and a soybean protein encoded by pGmPM2 cDNA. Molecular analysis of the deduced protein reveals a 33 kDa acidic and extremely hydrophilic protein with potential amphiphilic -helical regions. In addition, the protein contains eleven similar, contiguous repeats of 11 amino acids, which are separated by 118 amino acids from two additional and unique repeats of 36 residues each at the carboxyl end of the protein. Comparisons of sequences of reported group 3 LEA proteins revealed that there are two types, separable by sequence similarity of the 11 amino acid repeating motifs and by the presence or absence of a certain amino acid stretch at the carboxyl terminus. Based on resuls from these comparisons, we propose a second type of group 3 LEA proteins, called group 3 LEA (II). 相似文献
138.
埃及血吸虫毛蚴表皮板共有4排,各排数目为6:9:4:3。除第1排之外,其他各排的表皮板均由无纤毛的嵴所分隔,在第1与第2排之间的环嵴中,除第1排各板底边中央小凹处各有1感受器外,尚可见4对感受器。第2与第3排的环嵴内可见16—20个感受器。此外,于体之两侧第3排表皮板间各见1个排泄孔。顶突似六边形,于其两侧各有1个侧腺开口,其内侧可见14个感受器。本文在讨论中与前人对本虫毛蚴表皮板的描述做了简单比较。 相似文献
139.
Jun-Xian Zhang Jennifer Martin Harry J. Flint 《Molecular genetics and genomics : MGG》1994,245(2):260-264
xynB is one of at least four genes from the cellulolytic rumen anaerobe Ruminococcus flavefaciens 17 that encode xylanase activity. The xynB gene is predicted to encode a 781-amino acid product starting with a signal peptide, followed by an amino-terminal xylanase domain which is identical at 89% and 78% of residues, respectively, to the amino-terminal xylanase domains of the bifunctional XynD and XynA enzymes from the same organism. Two separate regions within the carboxy-terminal 537 amino acids of XynB also show close similarities with domain B of XynD. These regions show no significant homology with cellulose- or xylan-binding domains from other species, or with any other sequences, and their functions are unknown. In addition a 30 to 32-residue threonine-rich region is present in both XynD and XynB. Codon usage shows a consistent pattern of bias in the three xylanase genes from R. flavefaciens that have been sequenced. 相似文献
140.
介绍一种IBM-PC系列微机生理信号采集、处理系统。该系统信号采集卡集程控放大、脉冲甄别、A/D、D/A等电路于一体,可满足各种生理信号的采集需要。采集信号时可长时间显示,动态观察。采样后,按需要给出各种图表与结果。部分处理方法采用独特数学模型,使结果更加精确。 相似文献