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1.
New Books     
Book reviewed in this article: Dunbar , R. 1997: Grooming, Gossip and the Evolution of Language. Höglund, J. & Alatalo , R. V. 1995: Leks. Wuketits , F. M. 1997: Soziobiologie. Die Macht der Gene und die Evolution sozialen Verhaltens. Sachs , L. 1997: Angewandte Statistik - Anwendung statistischer Methoden.  相似文献   

2.
The main manganese peroxidase isoenzyme MnP2 of the South American white-rot fungus Nematoloma frowardii b19 was purified to homogeneity using anion-exchange chromatography (Mono Q) and preparative isoelectric focusing. The purified enzyme has a molecular mass of 44 kDa and a pI of 3.2. Received: 23 May 1997 / Received revision: 1 July 1997 / Accepted: 4 July 1997  相似文献   

3.
Book Reviews     
Book Reviewed in this article:
Ax, P.: Multicellular Animals. A new Approach to the Phylogenetic Order in Nature .
R idley , M.: Evolution 2nd ed.
R idley , M: Evolution. CD-ROM .
X ianguang , H. & B ergström , J. 1997. Arthropods of the Lower Cambrian Chengjiang fauna, south-west China .
P h . G randcolas (ed.) 1997: The origin of biodiversity in insects: phylogenetic tests of evolutionary scenarios .
S teinmann , H., 1997. World catalogue of Odonata. Vol. 1: Zygoptera, Vol. 2: Anisoptera .
J esses , S. 1997. Trace fossils from the Lower Cambrian Mickwitzia sandstone, south central Sweden .  相似文献   

4.
New Books     
Book reviewed in this article: Wrangham, R. W., McGrew, W. C., de Waal, F. B. M. & Heltne , P. G. (eds) 1996: Chimpanzee Cultures. Lewkowicz, D. J. & Lickliter , R. (eds) 1994: The Development of Intersensory Perception. Maffei, L. & Fiorentini , A. 1997: Das Bild im Kopf (Originaltitel: Arte e Cervello. Pearce , J.M. 1997: Animal Learning and Cognition. Gould, J. L., & Gould , C. G. 1997: Bewußtsein bei Tieren.  相似文献   

5.
New Books     
Book reviewed in this article: Hauser , M. D. 1996: The evolution of communication. Runciman , W. G., Maynard Smith , J. & Dunbar , R. I. M. (eds) 1996: Evolution of Social Behaviour Patterns in Primates and Man. Snowdon , C. T. & Hausberger , M. (eds) 1997: Social Influences on Vocal Development. Wyrwicka , W. 1996: Imitation in Human and Animal Behaviour. Waal , F. de & Lanting , F. 1997: Bonobo: The forgotten ape. Witte , G. R. 1997: Der Maulwurf, Talpa europaea. Neuc Brehm-Bücherei Nr. 637.  相似文献   

6.
Objective: To determine secular trends in overweight/obesity among 7‐ to 15‐year‐olds for the periods 1985, 1997, and 2004. Research Method and Procedures: Data from representative surveys conducted in New South Wales, Australia, in 1985, 1997, and 2004 were analyzed. Height and weight were measured, and BMI categories were created using International Obesity Task Force definitions. Students were grouped as Grades 2 + 4 + 6 and 8 + 10. Results: The prevalences of overweight/obesity for 1985, 1997, and 2004 were 10.9%, 20.6%, and 25.7% among the younger boys and 10.6%, 19.5%, and 26.1% among the older boys. The average annual rate of increase for 1985 to 1997 was 0.81% and for 1997 to 2004 was 0.73% among the younger boys and was 0.74% and 0.94% for the two periods among the older boys. The prevalences of overweight/obesity in 1985, 1997, and 2004 were 14.0%, 22.0%, and 24.8% among the younger girls and 8.3%, 17.9%, and 19.8% among the older girls, respectively. The average annual rates of increase for the two periods were 0.8% and 0.4% among the younger girls and 0.80% and 0.27% among the older girls. Change in the prevalence of overweight/obesity and socioeconomic status were not associated. Discussion: Over the period 1985 to 1997, the prevalence of overweight and obesity increased significantly among the younger and older boys and the younger girls. The prevalence of overweight, but not obesity, increased among the older girls over this period. Over the period 1997 to 2004, the prevalence of overweight/obesity combined increased significantly among boys of both age groups but not among girls.  相似文献   

7.
Somatic embryogenesis was observed in callus initiated from tendril explants of Vitis vinifera L. cvs. Thompson, Sonaka and Tas-e-Ganesh on Emershad and Ramming medium supplemented with 1 μm 6-benzylaminopurine. Low-frequency conversion to shoots was obtained in the third and fourth subculture on the same medium. Emerging shoots subsequently formed complete plantlets on liquid rooting medium containing 1 μm indole-3-acetic acid. The possible use of tendrils as a novel explant for somatic embryogenesis in grape is discussed. Received: 3 March 1997 / Revision received: 21 May 1997 / Accepted: 25 June 1997  相似文献   

8.
Unpollinated ovaries of Hyoscyamus muticus L. (commonly known as Egyptian henbane) were cultured on Murashige and Skoog and Bourgin and Nitsch media supplemented with various growth hormones to study the organogenesis, embryogenesis and regeneration of plantlets. Embryogenesis was reported for callus grown on both media containing 0.05 mg/l α-naphthaleneacetic acid and 0.5 mg/l 6-benzylaminopurine. Differentiation of roots and shoots from the calli also occurred in these media. Albinism or chlorophyll deficiency and variation in ploidy level were observed among the ovary-derived plantlets. Received: 7 April 1997 / Revised received: 2 August 1997 / Accepted: 2 September 1997  相似文献   

9.
The aim of this study was to assess trends in captive breeding of threatened and endangered bird species in British zoos. The measures we recorded were: 1) the total number of species held, 2) the percentage of species held that are listed in the IUCN Red List, 3) the percentage of endangered species breeding, and 4) the number of species in managed breeding programs. These data were gathered from the bird inventories of 10 representative British zoos for the years 1988 and 1997. The data for measures 1–3 were compared between the 2 years using a Wilcoxon matched‐pairs test. We found that the zoos maintained the same number of species (W=10.5; n=10; P=0.093; median=87.5 and 78 for 1988 and 1997, respectively). However, there was a significant increase in the number of birds held that fit each of the IUCN's conservation categories (Endangered: W=43.0; n=10; P<0.05, median=1.48 and 6.64 for 1988 and 1997, respectively; Vulnerable: W=53.0; n=10; P<0.05, median=3.33 and 10.05 for 1988 and 1997, respectively; and Rare: W=55.0; n=10; P<0.01, median=0.00 and 8.33 for 1988 and 1997, respectively). Overall, the percentage of threatened species kept in zoos increased from a median of 4.81 in 1988 to 25.02 in 1997. During this period there was an increase in the number of species in each category of the IUCN Red List. No difference was found in the number of threatened species breeding between 1988 and 1997. Zoo Biol 23:85–89, 2004. © 2004 Wiley‐Liss, Inc.  相似文献   

10.
Mutants that secrete increased amounts of enzyme into a selection medium can be efficiently enriched from large populations of mutagenized microorganisms during growth in hollow fibers. Under these conditions, each colony grows in its own microenvironment and cross-feeding between neighboring colonies is limited. We applied the technique to B. subtilis carrying a plasmid-encoded protease gene. The plasmid was subjected to random mutagenesis and clones secreting up to fivefold-increased amounts of enzyme were selected using a medium containing bovine serum albumin as the sole nitrogen source. Received: 22 May 1997 / Received revision: 21 October 1997 / Accepted: 7 November 1997  相似文献   

11.
5-Hydroxypyrazine-2-carboxylic acid, a versatile building block for the synthesis of new antituberculous agents, was prepared by whole-cell biotransformation from 2-cyanopyrazine via pyrazinecarboxylic acid using Agrobacterium sp. DSM 6336. By developing a fermentation process for this two-enzyme-step bioconversion, a product concentration of 286 mM (40 g/l) was obtained. After the isolation method had been optimized the total yield was 80%. Received: 28 February 1997 / Received revision: 28 April 1997 / Accepted: 4 May 1997  相似文献   

12.
A partial cDNA clone, from the 3′ end of the dragline silk gene was isolated from Nephila clavipes major ampullate glands. This clone contains a 1.7-kb insert, consisting of a repetitive coding region of 1.4-kb and a 0.3-kb nonrepetitive coding region; 1.5-kb of the 1.7-kb fragment was cloned into Escherichia coli and a␣43-kDa recombinant silk protein was expressed. Characterization of the purified protein by Western blot, amino acid composition analysis, and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry confirms it to be spider dragline silk. Received: 7 April 1997 / Received revision: 24 July 1997 / Accepted: 25 August 1997  相似文献   

13.
Biotechnological production of flavours and fragrances   总被引:7,自引:0,他引:7  
The biotechnological generation of natural aroma compounds is rapidly expanding. Aroma chemicals, such as vanillin, benzaldehyde (bitter almond, cherry) and 4-(R)-decanolide (fruity–fatty) are marketed on a scale of several thousand tons per year. Their possible production by single-step biotransformations, bioconversions and de novo synthesis using microorganisms, plant cells or isolated enzymes is shown. The perspectives of bioprocesses for the oxifunctionalisation of lower terpenes by genetically modified organisms and economic aspects are discussed. Received: 27 May 1997 / Received revision: 25 September 1997 / Accepted: 28 September 1997  相似文献   

14.
The biolistic particle delivery system was used to transfer the uidA gene into different garlic tissues, including regenerable calli. These tissues showed a high endogenous nuclease activity preventing exogenous DNA expression. After submerging the tissues for 24 h in a 2 mm solution of the nuclease inhibitor aurintricarboxylic acid, transient expression of the uidA gene was detected. Furthermore, vacuum infiltration of aurintricarboxylic acid into the garlic tissues significantly increased the percentage of explants showing transient expression. Among four plasmids tested, pDE4 containing the CaMV35S-uidA construct produced the best results. Received: 16 May 1997 / Revision received: 26 August 1997 / Accepted: 25 September 1997  相似文献   

15.
No increases in exopolysaccharide (EPS) yields in Aureobasidium pullulans were observed when grown with reduced-shear impellers instead of standard Rushton turbines in the same vessel. However, yields were dramatically reduced when the organism was grown in an airlift reactor. This fall in production could be counteracted by improving fluid circulation through the placement of impellers within the draught tube, a strategy that resulted in the highest EPS concentration (approx. 13 g l−1) of all the fermenter configurations tested. Received: 24 June 1997 / Revised revision: 25 September 1997 / Accepted: 29 September 1997  相似文献   

16.
The gene for the thermostable pyruvate kinase of Microbispora thermodiastatica IFO 14046, a moderate thermophilic actinomycete, was cloned in Escherichia coli. This gene consists of an open reading frame of 1422 nucleotides and encodes a protein of 474 amino acids with molecular mass of 50 805 Da. The open reading frame was confirmed as the pyruvate kinase gene by comparison with the N-terminal amino acid sequence of the purified pyruvate kinase from M. thermodiastatica. Received: 19 May 1997 / Received last revision: 22 September 1997 / Accepted: 14 October 1997  相似文献   

17.
New Books     
Book reviewed in this article: Ito, M . (ed.), 1997: Brain and Mind. For better understanding of the dynamic function of mind and its supporting brain mechanisms. A collection of contributions based on lectures presented at the ninth TOYOTA Conference, Mikkabi, Shizuoka, Japan, Dec. 5–8, 1995. Thier, P. & Karnath, H.-O. , (eds), 1997: Parietal Lobe Contributions to Orientation in 3D Space. del Hoyo, K., Elliot, A. & Sargatal , J. (eds) 1996: Handbook of the Birds of the World, Vol. 111. Hoatzin to Auks. Sambraus, H. H. & Steiger , A. (eds) 1997: Das Buch vom Tierschutz.  相似文献   

18.
An efficient one-step transformation method for the dimorphic yeast Yarrowia lipolytica is described. Using cells grown overnight on agar plates, the whole process is carried out within 1 h. The transformant clones could be recovered on selective plates as early as 36–48 h after plating. The efficiency was better than 105 transformants/μg replicative plasmid DNA. Effects of cell density, dithiothreitol, heat shock, poly(ethylene glycol) 4000 concentration and the wetness of selective plates were investigated. Received: 17 February 1997 / Received revision: 4 April 1997 / Accepted: 19 April 1997  相似文献   

19.
An automated system for on-line measurement of enzyme activity is proposed. The system uses a flow injection manifold in the stopped-flow mode to measure initial reaction rates. The time during which the flow is halted is selected in such a way as to optimise the enzyme/substrate ratio for the correct determination of activity values. The proposed system was used to determine the activity of laccase produced by the fungus Trametes versicolor immobilised on nylon in a fixed-bed reactor used for treating pulp mill waste water. Received: 17 February 1997 / Received revision: 23 April 1997 / Accepted: 27 April 1997  相似文献   

20.
Drawing Shadows to Stone: Photographing North Pacific Peoples (1897-1902). American Museum of Natural History, New York, New York, November 14, 1997- March 1, 1998.
Drawing Shadows to Stone: The Photography of the Jesup North Pacific Expedition, 1897-1902. Laurel Kendall. Barbara Mathé. and Thomas Ross Miller. with Stanley A. Freed. Ruth S. Freed. and Laila Williamson. New York: American Museum of Natural History, 1997, and Seattle: University of Washington Press, 1997. 112 pp., 97 illust.  相似文献   

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