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21.
Nucleic acids from 41 strains of Metarhizium anisopliae, obtained from different parts of the world were extracted and examined by electrophoresis. Strong bands of double‐stranded RNA (dsRNA) were detected in two isolates from Brazil, V215 and V291, which had, respectively, 13 and 9 distinct bands ranging in size from ca. 0.75 to 3.5 kb. Icosahedral virus‐like particles (VLPs) (ca. 33 nm in diameter) were observed by transmission electron microscopy in extracts of these isolates. The VLPs and dsRNA were both absent from a clone of the isolate V291 which had been subcultured successively on solid medium. Bioassays against the aphid Myzus persicae showed no detectable difference in virulence between the clone of V291 which contained dsRNA and the clone that did not.  相似文献   
22.
Abstract The sequence of the cohesive ends of actinophage RP3 DNA has been determined. As with all other phages of Gram-positive bacteria that have been studied sofar, RP3 DNA has 3'-protruding ends. A shuttle cosmid has been constructed containing this cos area which can be efficiently transduced by phage RP3 to host cells of Streptomyces rimosus .  相似文献   
23.
Methanobacterium thermoautotrophicum was grown on a defined mineral salts medium under strictly anaerobic conditions with H2 and CO2 as the sole energy and carbon sources, respectively. The cultivation medium was optimized with respect to non-organic components including Se(IV), W(VI), N, Ni(II), Fe(II), Co(II) and Mo(VI). Sulphide concentration in the medium was maintained constant using an on-line regulatory system by the addition of 0.5 M Na2S. A maximum supply rate of 0.6 vvm of a mixture of 80% H2 and 20% CO2 was achieved for the gaseous substrates. Under these conditions a specific growth rate of 0.30 h–1 and a cell concentration of 4.8 g cell dry weight (DW) l–1, representing a 140% increase over previously published results, were obtained. The growth yield of 2.3 g DW mol–1 CH4 was similar to published values. However, the overall specific productivity was enhanced from 11 mmol CH4 g–1 DW h–1 to 24 mmol CH4 g–1 DW h–1, corresponding to an improvement of 120%. Correspondence to: U. von Stockar  相似文献   
24.
Two Corynebacterium glutamicum strains, one being glutamate dehydrogenase (GDH) negative and the other possessing 11-fold-higher specific GDH activity than the parental wild type, were constructed and used to analyze the role of GDH in C. glutamicum. The results indicate (i) that GDH is dispensable for glutamate synthesis required for growth and (ii) that although a high level of GDH increases the intracellular glutamate pool, the level of GDH has no influence on glutamate secretion.  相似文献   
25.
We have performed a high-resolution linkage analysis for the conserved segment on distal mouse Chromosome (Chr) 8 that is homologous to human Chr 16q. The interspecific backcross used involved M. m. molossinus and an M. m. domesticus line congenic for an M. spretus segment from Chr 8 flanked by phenotypic markers Os (oligosyndactyly) and e, a coat colormarker. From a total of 682 N2 progeny, the 191 animals revealing a recombination event between these phenotypic markers were typed for 23 internal loci. The following locus order with distances in cM was obtained: (centromere)–Os–4.1–Mmp2–0.2–Ces1,Es1, Es22–1.2–Mt1,D8Mit15–2.2–Got2, D8Mit11–3.7–Es30–0.3–Es2, Es7–0.9–Ctra1,Lcat–0.3–Cdh1, Cadp, Nmor1, D8Mit12–0.2–Mov34–2.5–Hp,Tat–0.2–Zfp4–1.6–Zfp1,Ctrb–10.9–e. In a separate interspecific cross involving 62 meioses, Dpep1 was mapped together with Aprt and Cdh3 at 12.9 cM distal to Hp, Tat, to the vicinity of e. Our data give locus order for markers not previously resolved, add Mmp2 and Dpep1 as new markers on mouse Chr 8, and indicate that Ctra1 is the mouse homolog for human CTRL. Comparison of the order of 17 mouse loci with that of their human homologs reveals that locus order is well conserved and that the conserved segment in the human apparently spans the whole long arm of Chr 16. Received: 30 July 1996 / Accepted: 15 November 1996  相似文献   
26.
cDNAs encoding three proteins from barley ( Hordeum vulgare ), a class-II chitinase (CHI), a class-II β-1,3-glucanase (GLU) and a Type-I ribosome-inactivating protein (RIP) were expressed in tobacco plants under the control of the CaMV 35S-promoter. High-level expression of the transferred genes was detected in the transgenic plants by Northern and Western blot analysis. The leader peptides in CHI and GLU led to accumulation of these proteins in the intercellular space of tobacco leaves. RIP, which is naturally deposited in the cytosol of barley endosperm cells, was expressed either in its original cytosolic form or fused to a plant secretion peptide (spRIP). Fungal infection assays revealed that expression of the individual genes in each case resulted in an increased protection against the soilborne fungal pathogen Rhizoctonia solani , which infects a range of plant species including tobacco. To create a situation similar to 'multi-gene' tolerance, which traditional breeding experience has shown to provide crops with a longer-lasting protection, several of these antifungal genes were combined and protection against fungal attack resulting from their co-expression in planta was evaluated. Transgenic tobacco lines were generated with tandemly arranged genes coding for RIP and CHI as well as GLU and CHI. The performance of tobacco plants co-expressing the barley transgenes GLU/ CHI or CHI/RIP in a Rhizoctonia solani infection assay revealed significantly enhanced protection against fungal attack when compared with the protection levels obtained with corresponding isogenic lines expressing a single barley transgene to a similar level. The data indicate synergistic protective interaction of the co-expressed anti-fungal proteins in vivo .  相似文献   
27.
Summary We report a newborn with incontinentia pigmenti Bloch-Sulzberger and male phenotype. Chromosome analysis revealed a Klinefelter's syndrome 47,XXY. These findings are compatible with the hypothesis of dominant sexlinked genes carried on the X-chromosome in this disease.
Zusammenfassung Wir berichten über ein neugeborenes Kind mit männlichem Phänotyp bei Incontinentia pigmenti Bloch-Sulzberger. Bei der klinischen Abklärung fand sich die Gonosomenaberration eines Klinefelter-Syndroms 47,XXY. Dieser Befund geht konform mit der Vermutung eines dominant X-gekoppelten Erbganges dieser seltenen Hauterkrankung.
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28.
Twenty five patients with hyperprolactinaemia were treated with pergolide mesylate, a new dopamine receptor agonist. Twenty three received treatment for six to 20 months, and in all serum prolactin concentrations were considerably reduced. In most patients prolactin concentrations were maintained in the normal range by a low, once daily dose of pergolide and reversal of associated reproductive disorders was observed. Tumour volume as assessed by computed tomography decreased considerably during treatment in three out of four patients with a pituitary tumour. The drug was well tolerated. Side effects were similar to those of bromocriptine, but four out of eight patients who had been forced to stop taking bromocriptine because of untoward effects were subsequently able to tolerate treatment with pergolide. Pergolide mesylate promises to be a useful addition to the currently available long acting dopamine agonists in the management of hyperprolactinaemia.  相似文献   
29.
30.
Ohne Zusammenfassung
Long-term telemetry of body temperature with synchronous measurement of metabolic rate in torpid and non-torpid Blue-naped Mousebirds (Urocolius macrourus)
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