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81.
The distributed annotation system (DAS) defines a communication protocol used to exchange biological annotations. It is motivated by the idea that annotations should not be provided by single centralized databases but instead be spread over multiple sites. Data distribution, performed by DAS servers, is separated from visualization, which is carried out by DAS clients. The original DAS protocol was designed to serve annotation of genomic sequences. We have extended the protocol to be applicable to macromolecular structures. Here we present SPICE, a new DAS client that can be used to visualize protein sequence and structure annotations. AVAILABILITY: http://www.efamily.org.uk/software/dasclients/spice/  相似文献   
82.
Consistency in gold chloride staining is essential for anatomical analysis of sensory nerve endings. The gold chloride stain for this purpose has been modified by many investigators, but often yields inconsistent staining, which makes it difficult to differentiate structures and to determine nerve ending distribution in large tissue samples. We introduce additional steps and major changes to the modified Gairns’ protocol. We controlled the temperature and mixing rate during tissue staining to achieve consistent staining and complete solution penetration. We subjected samples to sucrose dehydration to improve cutting efficiency. We then exposed samples to a solution containing lemon juice, formic acid and paraformaldehyde to produce optimal tissue transparency with minimal tissue deformity. We extended the time for gold chloride impregnation 1.5 fold. Gold chloride was reduced in the labrum using 25% formic acid in water for 18 h and in the capsule using 25% formic acid in citrate phosphate buffer for 2 h. Citrate binds gold nanoparticles, which minimizes aggregation in the tissue. We stored samples in fresh ultrapure water at 4° C to slow reduction and to maintain color contrast in the tissue. Tissue samples were embedded in Tissue Tek and sectioned at 80 and 100 μm instead of using glycerin and teasing the tissue apart as in Gairns’ modified gold chloride method. We attached sections directly to gelatin subbed slides after sectioning with a cryostat. The slides then were processed and coverslipped with Permount. Staining consistency was demonstrated throughout the tissue sections and neural structures were clearly identifiable.  相似文献   
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From a partial genomic library enriched for GATA short tandem repeats, we developed 12 polymorphic microsatellite loci from the green‐backed tit (Parus monticolus). We characterized these loci by genotyping 30 adult individuals with unknown relationship. The number of alleles ranged from four to 17 per locus (mean = 9.3 alleles) and the observed heterozygosity for each locus ranged from 0.633 to 0.933 (mean = 0.789). All loci conformed to Hardy–Weinberg expectations. Four of 66 possible pairwise comparisons between loci showed significant gametic disequilibrium.  相似文献   
85.
Five patients at risk for primary central nervous system lymphoma (PCNSL) recurrence were treated with high-dose methylprednisolone, (HDMP) to prevent ‘trafficking’ of malignant lymphocytes into the central nervous system (CNS). HDMP was chosen because of its ability to stabilize the ‘blood brain barrier (BBB)’. Three men with newly diagnosed PCNSL, ages 62, 76 and 78 y, whose survival was projected to be 6.6 months, began treatment after achieving complete response (CR) to initial radiation therapy alone and survived 27, 37 and 59 months after treatment. In none was death from recurrent disease in CNS but one patient did die of systemic non-Hodgkin’s lymphoma (NHL) five years after PCNSL diagnosis. A 20 y old man was treated with HDMP after successful combined modality therapy and is alive 75+months after initial diagnosis without evidence of disease recurrence. A 34 y old man relapsed after combined modality initial treatment and failed to respond to HDMP when treatment was begun after unsuccessful salvage therapy; he died of disease 12 months after initial diagnosis. There were no treatment complications. The promising results in this pilot study from the basis for a North Central Cancer Treatment Group (NCCTG) 96-73-51, a Phase 2 clinical trial of brain radiotherapy and HDMP for PCNSL patients 70 y of age and older, a group of patients at high risk for toxicity from intensive combined modality therapy.  相似文献   
86.
Eph receptor tyrosine kinases (RTK) and their ephrin ligands are involved in the transmission of signals which regulate cytoskeletal organisation and cell migration, and are expressed in spatially restricted patterns at discrete phases during embryogenesis. Loss of function mutants of Eph RTK or ephrin genes result in defects in neuronal pathfinding or cell migration. In this report we show that soluble forms of human EphA3 and ephrin-A5, acting as dominant negative inhibitors, interfere with early events in zebrafish embryogenesis. Exogenous expression of both proteins results in dose-dependent defects in somite development and organisation of the midbrain-hindbrain boundary and hindbrain. The nature of the defects as well as the distribution and timing of expression of endogenous ligands/receptors for both proteins suggest that Eph-ephrin interaction is required for the organisation of embryonic structures by coordinating the cellular movements of convergence during gastrulation.  相似文献   
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R Cushman  J Down  N MacMillan  H Waclawik 《CMAJ》1990,143(2):108-112
The number of bicycle-related injuries has risen significantly with the increased popularity of bicycle riding in Canada. The risk of injury is highest among children. To assess the magnitude of the problem and to identify the contributing factors we used a questionnaire, injury reports and patient charts to survey bicycle-related injuries among children brought to the emergency department of the Children''s Hospital of Eastern Ontario, Ottawa, between May 1 and Sept. 30, 1988. The questionnaire was completed for 517 (91%) of the 568 children; 70% were boys, and the mean age was 9.4 years. Only 2% of the patients had been wearing a helmet at the time of injury, although 13% claimed to own one for cycling. Over 60% of the accidents were attributable to carelessness or poor bicycle control; mechanical failure and environmental hazards were minor factors. Over 80% of the injuries occurred within a kilometre of the child''s home. Of the 97 children admitted to hospital 49% had head and skull injuries and 40% had limb fractures. Bicycle-related injuries represented 14.8% of all nonwinter (Apr. 1 to Oct. 31) trauma admissions among children 5 years or older. Our results further document bicycle-related injuries as an important childhood problem and underscore the need for improved safety measures.  相似文献   
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OXYGEN RELATIONS OF THE ROOT NODULES OF ALNUS RUBRA BONG.   总被引:2,自引:1,他引:1  
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