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1.
This study continues analysis from a companion paper on over 350,000 insured Swedish dogs up to 10 years of age contributing to more than one million dog-years at risk during 1995–2000. The age patterns for total and diagnostic mortality and for general causes of death (trauma, tumour, locomotor, heart and neurological) are presented for numerous breeds. Survival estimates at five, eight and 10 years of age are calculated. Survival to 10 years of age was 75% or more in Labrador and golden retrievers, miniature and toy poodles and miniature dachshunds and lowest in Irish wolfhounds (91% dead by 10 years). Multivariable analysis was used to estimate the relative risk for general and more specific causes of death between breeds accounting for gender and age effects, including two-way interactions. Older females had tumour as a designated cause of death more often than males in most breeds, but not in the Bernese mountain dog. Information presented in this and the companion paper inform our understanding of the population level burden of disease, and support decision-making at the population and individual level about health promotion efforts and treatment and prognosis of disease events.  相似文献   
2.
Active application of gold nanoparticles for various diagnostic and therapeutic purposes started in recent decades due to the emergence of new data on their unique optical and physicochemical properties. In addition to colloidal gold conjugates, growth in the number of publications devoted to the synthesis and application of multifunctional nanocomposites has occurred in recent years. This review considers the application in biomedicine of multifunctional nanoparticles that can be produced in three different ways. The first method involves design of composite nanostructures with various components intended for either diagnostic or therapeutic functions. The second approach uses new bioconjugation techniques that allow functionalization of gold nanoparticles with various molecules, thus combining diagnostic and therapeutic functions in one medical procedure. Finally, the third method for production of multifunctional nanoparticles combines the first two approaches, in which a composite nanoparticle is additionally functionalized by molecules having different properties.  相似文献   
3.
With the method of dynamic light scattering it was shown that the average size of micelles in the series of formulations based on various clindamycin salts, i. e. ClindHCl+Tween-20, ClindBz+Tween-20, ClindHCl+Cremafor-EL and ClindBz+Cremafor-EL increased from 6 to 20 nm. Investigations with the agar diffusion method revealed that the bactericidic action of the micelle-capsulated therapeutics did not depend on the micelle size within 6 to 20 mn. The concentration of the micellar clindamycin or gentamicin equal to 0.05 mcg/ml was bacteriostatic with respect to Micrococcus (Sarsina) luteus.  相似文献   
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Genetic variation at the Major Histocompatibility Complex locus DQ beta wasanalyzed in 233 beluga whales (Delphinapterus leucas) from sevenpopulations: St. Lawrence Estuary, eastern Beaufort Sea, eastern ChukchiSea, western Hudson Bay, eastern Hudson Bay, southeastern Baffin Island,and High Arctic and in 12 narwhals (Monodon monoceros) sympatric with theHigh Arctic beluga population. Variation was assessed by amplification ofthe exon coding for the peptide binding region via the polymerase chainreaction, followed by either cloning and DNA sequencing or single-strandedconformation polymorphism analysis. Five alleles were found across thebeluga populations and one in the narwhal. Pairwise comparisons of thesealleles showed a 5:1 ratio of nonsynonymous to synonymous substitutions persite leading to eight amino acid differences, five of which werenonconservative substitutions, centered around positions previously shownto be important for peptide binding. Although the amount of allelicvariation is low when compared with terrestrial mammals, the nature of thesubstitutions in the peptide binding sites indicates an important role forthe DQ beta locus in the cellular immune response of beluga whales.Comparisons of allele frequencies among populations show the High Arcticpopulation to be different (P < or = .005) from the other belugapopulations surveyed. In these other populations an allele, Dele-DQbeta*0101-2, was found in 98% of the animals, while in the High Arctic itwas found in only 52% of the animals. Two other alleles were found at highfrequencies in the High Arctic population, one being very similar to thesingle allele found in narwhal.  相似文献   
5.
We report the complete sequence of a paralogous copy of elongation factor-1 alpha (EF-1 alpha) in the honeybee, Apis mellifera (Hymenoptera: Apidae). This copy differs from a previously described copy in the positions of five introns and in 25% of the nucleotide sites in the coding regions. The existence of two paralogous copies of EF-1 alpha in Drosophila and Apis suggests that two copies of EF-1 alpha may be widespread in the holometabolous insect orders. To distinguish between a single, ancient gene duplication and parallel, independent fly and bee gene duplications, we performed a phylogenetic analysis of hexapod EF-1 alpha sequences. Unweighted parsimony analysis of nucleotide sequences suggests an ancient gene duplication event, whereas weighted parsimony analysis of nucleotides and unweighted parsimony analysis of amino acids suggests the contrary: that EF-1 alpha underwent parallel gene duplications in the Diptera and the Hymenoptera. The hypothesis of parallel gene duplication is supported both by congruence among nucleotide and amino acid data sets and by topology-dependent permutation tail probability (T-PTP) tests. The resulting tree topologies are also congruent with current views on the relationships among the holometabolous orders included in this study (Diptera, Hymenoptera, and Lepidoptera). More sequences, from diverse orders of holometabolous insects, will be needed to more accurately assess the historical patterns of gene duplication in EF-1 alpha.   相似文献   
6.
A protein assay based on colloidal gold conjugates with trypsin   总被引:2,自引:0,他引:2  
The standard sol particle immunoassay (SPIA) is based on a biospecific aggregation of gold nanoparticle conjugates, followed by conventional spectrophotometry. Here we propose a novel SPIA format that uses microtitration immunological plates and an enzyme-linked immunosorbent assay reader. The novel and standard assays are exemplified by determination of immunoglobulin G by using 15-nm colloidal gold-protein A conjugates. We also describe a novel sol particle-trypsin assay using conjugates of gold nanoparticles with trypsin. The method is based on measuring spectral extinction changes caused by the addition of protein to a conjugate solution. The changes in the extinction spectra are presumed to be related to aggregation of gold nanoparticles caused by polyvalent binding of protein molecules to the trypsin molecules of the conjugates.  相似文献   
7.
Two variants of a method for determining the average composition of insoluble immune complex particles (IICP) are described. The first variant is based on measuring the specific turbidity (the turbidity per unit mass concentration of the dispersed substance) and the average size of IICP determined from dynamic light scattering (DLS). In the second variant, the slope of the logarithmic turbidity spectrum (wavelength exponent) is used instead of DLS particle size. Both variants allow the average biopolymer volume fraction to be determined in terms of the average refractive index of IICP. The method is exemplified by two experimental antigen+antibody systems: (i) lipopolysaccharide-protein complex (LPPC) of Azospirillum brasilense Sp245+rabbit anti-LPPC; and (ii) human IgG (hIgG)+sheep anti-hIgG. We have found that IICP can be modeled by incompact porous particles that contain about 30% of biopolymer substance and 70% of buffer.  相似文献   
8.
    

Background  

Calcineurin (CaN) is an important serine-threonine phosphatase (PP2B), which plays a crucial role in calcium-calmodulin mediated signal transduction events. Calcineurin has been implicated in pathogenesis of various diseases cardiac hypertrophy, diabetic neuropathy and Alzheimer's, however its role in neoplasia remains unclear.  相似文献   
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We studied grafted tumors obtained by subcutaneous implantation of kidney cancer cells into male white rats. Gold nanorods with a plasmon resonance of about 800 nm were injected intratumorally for photothermal heating. Experimental irradiation of tumors was carried out percutaneously using a near-infrared diode laser. Changes in the optical properties of the studied tissues in the spectral range 350–2200 nm under plasmonic photothermal therapy (PPT) were studied. Analysis of the observed changes in the absorption bands of water and hemoglobin made it possible to estimate the depth of thermal damage to the tumor. A significant decrease in absorption peaks was observed in the spectrum of the upper peripheral part and especially the tumor capsule. The obtained changes in the optical properties of tissues under laser irradiation can be used to optimize laboratory and clinical PPT procedures.  相似文献   
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