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991.
A cell line, designated NOCC, was established from the ascites of a patient with clear cell adenocarcinoma of the ovary. The cell line has been grown without interruption and continuously propagated by serial passaging (more than 76 times) over 7 years. The cells are spherical to polygonal-shaped, display neoplastic, and pleomorphic features, and grow in a jigsaw puzzle-like pattern while forming monolayers without contact inhibition. The cells proliferate rapidly, but are easily floated as a cell sheet. The population doubling time is about 29 h. The number of chromosomes ranges from 60 to 83. The modal number of chromosomes is 70–74 at the 30th passage. NOCC cells secreted 750.5 ng/ml of VEGF over 3 days of culture. Hypoxia inducible factor-1α (HIF-1α) is a primary regulator of VEGF under hypoxic conditions. NOCC cells were not sensitive to the anticancer drugs BEV, DOX, GEM, ETP, CDDP, or TXT. The graft of NOCC cells to a scid mouse displayed similar histological aspects to the original tumor. Both the NOCC cells and the graft of the NOCC cells gave a positive PAS reaction.  相似文献   
992.
We investigated hair bundle mechanoreceptors in sea anemones for a homolog of cadherin 23. A candidate sequence was identified from the database for Nematostella vectensis that has a shared lineage with vertebrate cadherin 23s. This cadherin 23-like protein comprises 6,074 residues. It is an integral protein that features three transmembrane alpha-helices and a large extracellular loop with 44 contiguous, cadherin (CAD) domains. In the second half of the polypeptide, the CAD domains occur in a quadruple repeat pattern. Members of the same repeat group (i.e., CAD 18, 22, 26, and so on) share nearly identical amino acid sequences. An affinity-purified antibody was generated to a peptide from the C-terminus of the cadherin 23-like polypeptide. The peptide is expected to lie on the exoplasmic side of the plasma membrane. In LM, the immunolabel produced punctate fluorescence in hair bundles. In TEM, immunogold particles were observed medially and distally on stereocilia of hair bundles. Dilute solutions of the antibody disrupted vibration sensitivity in anemones. We conclude that the cadherin 23-like polypeptide likely contributes to the mechanotransduction apparatus of hair bundle mechanoreceptors of anemones.  相似文献   
993.
A comparative evaluation of five different cell-disruption methods for the release of recombinant hepatitis B core antigen (HBcAg) from Escherichia coli was investigated. The cell disruption techniques evaluated in this study were high-pressure homogenization, batch-mode bead milling, continuous-recycling bead milling, ultrasonication, and enzymatic lysis. Continuous-recycling bead milling was found to be the most effective method in terms of operating cost and time. However, the highest degree of cell disruption and amounts of HBcAg were obtained from the high-pressure homogenization process. The direct purification of HBcAg from the unclarified cell disruptate derived from high-pressure homogenization and bead milling techniques, using batch anion-exchange adsorption methods, showed that the conditions of cell disruption have a substantial effect on subsequent protein recovery steps.  相似文献   
994.
Summary   Typhonium stigmatilobatum V. D. Nguyen, a new species from Vietnam, is described and illustrated.  相似文献   
995.

Background  

Simple Sequence Repeat (SSR) or microsatellite markers are valuable for genetic research. Experimental methods to develop SSR markers are laborious, time consuming and expensive. In silico approaches have become a practicable and relatively inexpensive alternative during the last decade, although testing putative SSR markers still is time consuming and expensive. In many species only a relatively small percentage of SSR markers turn out to be polymorphic. This is particularly true for markers derived from expressed sequence tags (ESTs). In EST databases a large redundancy of sequences is present, which may contain information on length-polymorphisms in the SSR they contain, and whether they have been derived from heterozygotes or from different genotypes. Up to now, although a number of programs have been developed to identify SSRs in EST sequences, no software can detect putatively polymorphic SSRs.  相似文献   
996.

Background  

Lipocalins are a large and diverse family of small, mostly extracellular proteins implicated in many important functions. This family has been studied in bacteria, invertebrate and vertebrate animals but little is known about these proteins in plants. We recently reported the identification and molecular characterization of the first true lipocalins from plants, including the Apolipoprotein D ortholog AtTIL identified in the plant model Arabidopsis thaliana. This study aimed to determine its physiological role in planta.  相似文献   
997.
The antifungal action of four essential oils of Foeniculum vulgare (fennel), Thymus vulgaris (thyme), Eugenia caryophyllata (Clove) and Salvia officinalis (sage) was tested in vitro against Penicillium digitatum Sacc. Direct contact and vapour phase were used to test the antifungal activity of these essential oils against P. digitatum that is responsible for green mould rot of citrus fruits. The vapour phase and direct contact of clove and thyme essential oils exhibited the strongest toxicity and totally inhibited the mycelial growth of the test fungus. Thyme and clove essential oils completely inhibited P. digitatum growth either when added into the medium 600 μl l−1 or by their volatiles with 24 μl per 8 cm diameter Petri dish. In in vitro mycelial growth assay showed fungistatic and fungicidal activity by clove and thyme essential oils. Sage and fennel oils did not show any inhibitory activity on this fungus. Scanning electron microscopy (SEM) was done to study the mode of action of clove oil in P. digitatum and it was observed that treatment with the oil leads to large alterations in hyphal morphology.  相似文献   
998.
Human knowledge is a phenomenon whose roots extend from the cultural, through the neural and the biological and finally all the way down into the Precambrian “primordial soup.” The present paper reports an attempt at understanding this Greater System of Knowledge (GSK) as a hierarchical nested set of selection processes acting concurrently on several different scales of time and space. To this end, a general selection theory extending mainly from the work of Hull and Campbell is introduced. The perhaps most drastic change from previous similar theories is that replication is revealed as a composite function consisting of what is referred to as memory and synthesis. This move is argued to drastically improve the fit between theory and human-related knowledge systems. The introduced theory is then used to interpret the subsystems of the GSK and their interrelations. This is done to the end of demonstrating some of the new perspectives offered by this view.
Claes AnderssonEmail:
  相似文献   
999.
During an occurrence of Hole-Rotten Disease of Laminaria japonica in a cultivating farm in Ma Shan Shandong province, China, 42 Gram-negative epiphytic marine bacteria were isolated and purified on Zobell 2216E marine agar medium. Morphological and biochemical characteristics of each isolated bacterium were studied, and molecular identification of bacterial strains was conducted with polymerase chain reaction amplification to 16S rRNA gene sequence analysis. Based on nearly full length of 16S rRNA gene sequence analysis, the isolated strains were bacteria that belong to genus Pseudoalteromonas, Vibrio, Halomonas and Bacillus. The percentage of each group was 61.9%, 28.6%, 7.1% and 2.4% respectively. The results of pathogenicity assay showed that 12 strains could cause the disease symptoms in sporophytes of L. japonica. They belonged to the genera Pseudoalteromonas, Vibrio and Halomonas with 58.3%, 33.3%, 8.3% respectively. The results suggest that these bacteria are the dominant marine bacteria on diseased sporophytes of L. japonica and may be the potential pathogenic bacteria associated with Hole-Rotten Disease of L. japonica.  相似文献   
1000.
To employ 16S rDNA PCR and automated sequencing techniques to identify a collection of bacterial veterinary pathogens from avian, equine, canine and ovine sources, that have proven difficult to identify, employing conventional cultural techniques. Universal or “broad-range” eubacterial PCR was performed on a collection of 46 difficult-to-identify bacterial isolates originating from clinical veterinary specimens. 16S rDNA PCR was performed using two sets of universal primers to successfully generate a composite amplicon of 1,068 bp, which was sequenced to obtain each isolate’s identity. Sequence analysis was able to identify all isolates examined with relative ease. Where the use of molecular identification methods is justified, such as in outbreak control or bioterrorism in animal health, employment of partial 16S rDNA PCR and sequencing employing universal or “broad-range” 16S rDNA, provides a valuable and reliable method of identification of such pathogens.  相似文献   
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