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The agropine type Agrobacterium rhizogenes strain LBA9402 induced callus and roots on stems of greenhouse grown plants and on leaf disks of in vitro grown plantlets of chrysanthemum (Dendranthema grandiflora Tzvel.). In this callus and roots no opines were detected, nor were any of the other features of the hairy root syndrome observed. Experiments aimed to identify the nature of the tumour-like growth revealed that induction was correlated with the presence of the TR-DNA on the Ri-plasmid. Root induction was probably the result of auxin synthesis following transient expression of iaaM and iaaH genes, present on the TR-DNA. The chrysanthemum cultivar used, cv. Parliament, showed a high auxin sensitivity compared to tobacco. Analysis of early transformation events using the GUSintron reporter gene revealed that low efficiency gene transfer and transient gene expression took place, but most probably without stable integration of the T-DNA in the plant genome. The results presented here stress the fact that callus formation or root induction as measures for transformation efficiency should be used with caution.  相似文献   
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Several animal viruses were treated with gamma radiation from a 60Co source under conditions which might be found in effluent from an animal disease laboratory. Swine vesicular disease virus, vesicular stomatitis virus, and blue-tongue virus were irradiated in tissues from experimentally infected animals. Pseudorabies virus, fowl plague virus, swine vesicular disease virus, and vesicular stomatitis virus were irradiated in liquid animal feces. All were tested in animals and in vitro. The D10 values, that is, the doses required to reduce infectivity by 1 log10, were not apparently different from those expected from predictions based on other data and theoretical considerations. The existence of the viruses in pieces of tissue or in liquid feces made no difference in the efficacy of the gamma radiation for inactivating them. Under the "worst case" conditions (most protective for virus) simulated in this study, no infectious agents would survive 4.0 Mrads.  相似文献   
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Twenty macropods from five locations in Queensland, Australia, grazing on a variety of native pastures were surveyed and the bacterial community of the foregut was examined using 454-amplicon pyrosequencing. Specifically, the V3/V4 region of 16S rRNA gene was examined. A total of 5040 OTUs were identified in the data set (post filtering). Thirty-two OTUs were identified as ‘shared’ OTUS (i.e. present in all samples) belonging to either Firmicutes or Bacteroidetes (Clostridiales/Bacteroidales). These phyla predominated the general microbial community in all macropods. Genera represented within the shared OTUs included: unclassified Ruminococcaceae, unclassified Lachnospiraceae, unclassified Clostridiales, Peptococcus sp. Coprococcus spp., Streptococcus spp., Blautia sp., Ruminoccocus sp., Eubacterium sp., Dorea sp., Oscillospira sp. and Butyrivibrio sp. The composition of the bacterial community of the foregut samples of each the host species (Macropus rufus, Macropus giganteus and Macropus robustus) was significantly different allowing differentiation between the host species based on alpha and beta diversity measures. Specifically, eleven dominant OTUs that separated the three host species were identified and classified as: unclassified Ruminococcaceae, unclassified Bacteroidales, Prevotella spp. and a Syntrophococcus sucromutans. Putative reductive acetogens and fibrolytic bacteria were also identified in samples. Future work will investigate the presence and role of fibrolytics and acetogens in these ecosystems. Ideally, the isolation and characterization of these organisms will be used for enhanced feed efficiency in cattle, methane mitigation and potentially for other industries such as the biofuel industry.  相似文献   
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The ecology of the uncultured, but large and morphologically conspicuous, rumen bacterium Oscillospira spp. was studied. Oscillospira-specific 16S rRNA gene sequences were detected in North American domestic cattle, sheep from Australia and Japan, and Norwegian reindeer. Phylogenetic analysis of the sequences obtained allowed definition of three operational taxonomic units within the Oscillospira clade. Consistent with this genetic diversity, we observed atypical smaller morphotypes by using an Oscillospira-specific fluorescence in situ hybridization probe. Despite the visual disappearance of typical large Oscillospira morphotypes, the presence of Oscillospira spp. was still detected by Oscillospira-specific PCR in the rumen of cattle and sheep. These observations suggest the broad presence of Oscillospira species in various rumen ecosystems with the level, and most likely the morphological form, dependent on diet. An ecological analysis based on enumeration of the morphologically conspicuous, large-septate form confirms that the highest counts are associated with the feeding of fresh forage diets to cattle and sheep and in two different subspecies of reindeer investigated.  相似文献   
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E. K. J. Risse, J. P. Holierhoek, E. M. Meijer‐Marres, E. Ouwerkerk‐Noordam and M. E. Boon Increased diagnostic accuracy of atypical glandular cells in cervical liquid‐based cytology using cell blocks Objective: The purpose of this study was to reduce the number of diagnoses of atypical glandular cells (AGC). Residual material from the cervical ThinPrep® samples (Hologic, Marlboruogh, MA, USA) was used for cell blocks (CB) and immunohistochemistry (IHC). Methods: In 2007 there were 87 patients (0.12% of tests) with AGC on liquid‐based cytology (LBC) in the Leiden Cytology and Pathology Laboratory (LCPL) using the Bethesda System 2001 (TBS). CB with IHC was used for 26 of these cases. The vials still containing the brush (Cervex‐Brush® Combi) were placed in a shaker for 10 minutes to dislodge the material trapped between the bristles. The residual sampling fluid was used to prepare paraffin sections (Shandon Cytoblock®) stained with Papanicolaou and immunostaining. Results: Four of five cases with AGC not otherwise specified (NOS) were diagnosed with CB/IHC as benign mimics (endometrium, tubal metaplasia, follicular cervicitis, microglandular hyperplasia) and one of four with AGC‐favour neoplasia (FN) (endocervical polyp). In one of five cases with AGC‐NOS and in two of seven with AGC‐FN, CIN3 was found on subsequent histological biopsy. Of six cases diagnosed as adenocarcinoma in situ (AIS) on LBC with CB/IHC the diagnosis was confirmed in four; one was adenocarcinoma and one glandular atypia. Of eight cases diagnosed as adenocarcinoma on cytology and CB/IHC, the diagnosis was confirmed in three. The other five cases were found to be one each of AIS, squamous cell carcinoma, CIN3, CIN2 with glandular atypia, and cervical endometriosis. Conclusions: By reducing the number of benign mimics of AGC, we achieved a high proportion (16/26; 61.5%) of neoplastic or preneoplastic lesions (glandular or squamous) on histological outcome potentially avoiding colposcopy. Histological biopsy verification by the gynaecologist is needed for final diagnosis of AGC‐FN, AIS and adenocarcinoma.  相似文献   
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