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71.
Palmer ND Fort S Starkey IR Shaw TR Northridge DB 《International journal of cardiovascular interventions》2000,3(3):161-165
BACKGROUND: The technique of coronary stenting has evolved over recent years, with improved stent technology and effective antiplatelet therapies to prevent stent thrombosis. In Europe, reductions in stent and equipment costs have resulted from increased market competition. The impact of these changes on the in-hospital procedural cost of percutaneous coronary intervention (PCI) in the current clinical setting is not known. METHODS: We compared the initial equipment and pharmaceutical costs of one hundred consecutive, unselected patients undergoing PCI in 1998 to a similar population who underwent PCI in 1994. RESULTS: Similar patient characteristics were noted, yet more complex disease (multivessel, AHA type B2/C lesions) was treated in the 1998 population. The stent utilization rate (83% vs 15%, p < 0.0001) and use of intravenous and/or oral antiplatelet therapy (abciximab, ticlopidine) (64% vs 4%, p < 0.0001) was higher in 1998. Similar angiographic success was achieved in each group with low complication rates. Mean hospital stay was reduced in the 1998 group (2.6 +/- 2.8 vs 4.3 +/- 3.8 days, p < 0.001). Repeat PCI was required more frequently in the 1994 population (26% vs 9%, p < 0.001). Overall there was no significant difference in the mean equipment cost between the two groups ( pound 1551 vs pound 1422, p=ns). CONCLUSION: Despite the widespread use of coronary stenting and antiplatelet therapies there appears to be no difference in current in-hospital equipment costs for PCI compared to 1994. Improved clinical outcomes in the 1998 population imply that stenting is a cost-effective therapy. 相似文献
72.
S Imai M Okumoto M Iwai S Haga N Mori N Miyashita K Moriwaki J Hilgers N H Sarkar 《Journal of virology》1994,68(5):3437-3442
Several groups of wild mice (Mus musculus) were captured from eight different locations in Asia and bred for several generations in a facility free of any laboratory strains of mice carrying mouse mammary tumor virus (MMTV). The distribution of endogenous MMTV proviral sequences in the liver tissues of these mice was investigated by using Southern blot hybridizations. Four categories of mice were identified. Mice originating from Bogor, Indonesia (Cas-Bgr); He-mei, Taiwan (Cas-Hmi/1); and Malaysia (Cas-Mal) were found to carry an endogenous MMTV provirus consisting of the env, gag-pol, and long terminal repeat sequences. Mice captured from Kojuri, Republic of Korea (Sub-Kjr); Nagoya, Japan (Mol-nag); and three Chinese provinces, Shanghai (Sub-Shh), Beijing (Sub-Bjn), and Jiayuguang (Sub-Jyg/1), appeared to carry defective proviruses. Some mice originating from He-mei (Cas-Hmi/2) and Jiayuguang (Sub-Jyg/2) were found to be completely free of endogenous MMTV. Interestingly, however, the Sub-Jyg/2 mice, after several generations of inbreeding, were found, unlike all of the other subspecies that we examined in the present study, to develop mammary tumors at a high incidence (80 to 90%) with a short period of latency. Electron microscopic examination of the mammary glands and mammary tumors of these mice revealed the presence of numerous intracytoplasmic A, immature, budding, and mature B particles. Furthermore, the mammary tumors were found to contain MMTV proviral sequences. It seems, therefore, that Sub-Jyg/2 mice carry an exogenous MMTV which contributes to their developing mammary tumors. 相似文献
73.
Influence of day length and temperature on number of main stem leaves and time to flowering in lupin
A growth chamber experiment was carried out to investigate the influence of day length and temperature on the development of flowering in eight varieties of the three grain lupin species Lupinus albus (Wat and C3396), L. angustifolius (Gungurru, Polonez and W26) and L. luteus, (Juno, Radames and Teo). The plants were grown at two temperatures, 10°C and 18°C, in combination with five daylength regimes: 10, 14, 18, 24 h day at full light intensity and 10 h full light extended with 8 h low intensity light. Increased daylength decreased days from sowing to flowering in all varieties, but had little effect on thermal time to flowering in most varieties. However, C3396, W26 and Radames had a significantly longer thermal time to flowering at high, non‐vernalising temperature (18°C) at short daylengths. Low light intensity daylength extension did not significantly influence thermal time to flowering. For flower initiation, measured as number of leaves on the main stem three types of response were found. All varieties formed fewer leaves on the main stem at 10°C than at 18°C, although the two thermo‐neutral varieties of L. luteus, Juno and Teo, gave only a small response to temperature and daylength. In Polonez, Gungurru and Wat, low temperature decreased leaf number, but there was only a small response to changes in daylength. Three varieties, C3396, W26 and Radames, showed longer thermal time to flowering at 18°C with short daylengths. This could be explained by a greater number of main stem leaves formed at short daylength at non‐vernalising temperatures. Increased daylength decreased leaf number in these varieties, but never to a smaller number than for plants grown at 10°C. In these varieties, low intensity extension of the daylength had a similar (W26, Radames) or decreased (C3396) effect compared to full light extension. The hastening of time to flowering by long days could be separated into two effects: a high light energy effect hastened development by increasing the rate of leaf appearance in all varieties, while low light energy in thermo‐sensitive varieties was able to substitute for vernalisation by decreasing leaf number. 相似文献
74.
Wandrille Duchemin Pierre-Yves Dupont Matthew A Campbell Austen RD Ganley Murray P Cox 《BMC bioinformatics》2014,16(1)
Background
Forming a new species through the merger of two or more divergent parent species is increasingly seen as a key phenomenon in the evolution of many biological systems. However, little is known about how expression of parental gene copies (homeologs) responds following genome merger. High throughput RNA sequencing now makes this analysis technically feasible, but tools to determine homeolog expression are still in their infancy.Results
Here we present HyLiTE – a single-step analysis to obtain tables of homeolog expression in a hybrid or allopolyploid and its parent species directly from raw mRNA sequence files. By implementing on-the-fly detection of diagnostic parental polymorphisms, HyLiTE can perform SNP calling and read classification simultaneously, thus allowing HyLiTE to be run as parallelized code. HyLiTE accommodates any number of parent species, multiple data sources (including genomic DNA reads to improve SNP detection), and implements a statistical framework optimized for genes with low to moderate expression.Conclusions
HyLiTE is a flexible and easy-to-use program designed for bench biologists to explore patterns of gene expression following genome merger. HyLiTE offers practical advantages over manual methods and existing programs, has been designed to accommodate a wide range of genome merger systems, can identify SNPs that arose following genome merger, and offers accurate performance on non-model organisms.Electronic supplementary material
The online version of this article (doi:10.1186/s12859-014-0433-8) contains supplementary material, which is available to authorized users. 相似文献75.
J
RGEN STENVIK METTE SERINE WESMAJERVI KJERSTI TURID FJALESTAD B
RGE DAMSGRD MADJID DELGHANDI 《Molecular ecology resources》2006,6(4):1105-1107
Microsatellites were identified by screening 2294 GenBank entries available for Atlantic cod (Gadus morhua L.), mainly representing expressed sequence tags and cDNA sequences. Ninety‐two novel microsatellite loci (tetra‐, tri‐ and dinucleotides) were characterized on 96 individuals. This strategy yielded 25 gene‐associated polymorphic microsatellite markers (11 tri‐ and 14 dinucleotides) with two to 20 alleles and an average heterozygosity of 0.48 in the population studied (range 0.02–0.89). One marker exhibited significant homozygote excess, and one of the primer pairs amplified two linked markers. The gene identity was determined at nine of the loci, confirming the associated microsatellites as type I markers. 相似文献
76.
Maria A Trainer David Capstick Alicja Zachertowska Kathy N Lam Scott RD Clark Trevor C Charles 《BMC microbiology》2010,10(1):92
Background
S. meliloti forms indeterminate nodules on the roots of its host plant alfalfa (Medicago sativa). Bacteroids of indeterminate nodules are terminally differentiated and, unlike their non-terminally differentiated counterparts in determinate nodules, do not accumulate large quantities of Poly-3-hydroxybutyrate (PHB) during symbiosis. PhaZ is in intracellular PHB depolymerase; it represents the first enzyme in the degradative arm of the PHB cycle in S. meliloti and is the only enzyme in this half of the PHB cycle that remains uncharacterized. 相似文献77.
Zusammenfassung Der Stiel der Pedizellarien von Arbacia lixula wurde lichtund elektronenoptisch untersucht und hinsichtlich seiner Funktion analysiert. Er besteht aus einem Bündel parallel angeordneter Calcitfasern, die distal von dem trabekulär aufgebauten Stielköpfchen zusammengefaßt werden; proximal enden sie frei. Zwischen den Skelettfasern im Inneren und als deutliche Ummantelung derselben finden sich parallel, sowie auch schraubig angeordnete Kollagenfasern unterschiedlicher Dicke. In den Raum zwischen den freien Enden der Calcitfasern und dem Gelenkhöcker der Corona schiebt sich ein funktionell wesentlicher Polster feiner Fibrillen, in den die Skelettfasern bei der Bewegung verschieden tief eintauchen können. Hinsichtlich der Innervation wird die Abspaltung einer Reihe von Nerven aus dem basalen Ringnerv, ihr freier Verlauf im Stiel und ihr Übertritt in die Mm. flexores des Pedizellarienköpfchens dargestellt. Aufgrund der erhobenen Befunde wird eine funktionelle Deutung dieser für Echinodermen besonderen Kombination von Skelett und organischem Fasermaterial gegeben.
Abkürzungen Abd M. abductor - Ax Axon - B Bügel - Bd Bandapparat - Bm Basalmembran - Cf Calcitfasern - dEf distale Endfläche - Ep Epidermis - Fl Mm. flexores - Fp Fibrillenpolster - Fpl Faserplatte - Gb Gleitbahn zwischen Stielköpfchen und Bügel - Gh Gelenkhöcker - Gk Gelenkkapsel - Kf Kollagenfibrille - Kfb Kollagenfaserbündel - LN Längsnerv - Mm Muskelmantel - ÖBd Öffnungen für den Bandapparat - Pig Pigment - pM peripherer Mantel aus Kollagenfasern - Sta Stachel - Stk Stielköpfchen - Z zelluläre Bestandteile im Inneren des Skelett-Kollagenzylinders - Za Zellausläufer - Zk Zellkerne der Bildungszone Mit Unterstützung des Fonds zur Förderung der wissenschaftlichen Forschung, Projekt-Nr.: 3425 相似文献
On the fine structure of the ophiocephalous pedicellariae from arbacia lixula L. (Echinodermata, Echinoidea). Functional analysis of the stalk
Summary The stalk of the pedicellariae from Arbacia lixula was investigated by the aid of light- and electron microscope and analysed regarding to its function. It consists of a bundle parallel arranged calcite rods concentrated distally in the head of the stalk, which is of trabecular construction; toward the corona they terminate freely without forming a joint surface. Inside, between the calcite rods and also as a distinct mantle around them, there are collagenous fibers of various thickness in parallel and spiral arrangement. In the lower part of the stalk the collagenous fibers pass over more and more to the peripheric mantle, which envelops the broader base of the stalk in constant thickness. Inside of the skeleton-collagen cylinder there appears now distinct accumulation of cells; their processes are to be find at the outer surface of the calcite fibers and their nuclei are arranged in a clear layer just above the joint region. In the area between the free ends of the calcite rods and the tubercle of the corona there is a cushion built up by fine fibrils. Its special function is given by the fact, that in any case of movement of the stalk, the calcite fibers are able to dip into this cushion more or less. Concerning the innervation, the separation of a series of nerves from the basal nerve ring, their free course in the stalk and their passing to the Mm. flexores of the head of pedicellaria is described. Based on all findings a functional interpretation for the special combination of skeleton and organic fibers is given.
Abkürzungen Abd M. abductor - Ax Axon - B Bügel - Bd Bandapparat - Bm Basalmembran - Cf Calcitfasern - dEf distale Endfläche - Ep Epidermis - Fl Mm. flexores - Fp Fibrillenpolster - Fpl Faserplatte - Gb Gleitbahn zwischen Stielköpfchen und Bügel - Gh Gelenkhöcker - Gk Gelenkkapsel - Kf Kollagenfibrille - Kfb Kollagenfaserbündel - LN Längsnerv - Mm Muskelmantel - ÖBd Öffnungen für den Bandapparat - Pig Pigment - pM peripherer Mantel aus Kollagenfasern - Sta Stachel - Stk Stielköpfchen - Z zelluläre Bestandteile im Inneren des Skelett-Kollagenzylinders - Za Zellausläufer - Zk Zellkerne der Bildungszone Mit Unterstützung des Fonds zur Förderung der wissenschaftlichen Forschung, Projekt-Nr.: 3425 相似文献
78.
Monoclonal antibodies against chicken type V collagen: production, specificity, and use for immunocytochemical localization in embryonic cornea and other organs 总被引:6,自引:17,他引:6 下载免费PDF全文
TF Linsenmayer JM Fitch TM Schmid Zak NB E Gibney RD Sanderson R Mayne 《The Journal of cell biology》1983,96(1):124-132
Two monoclonal antibodies have been produced against chick type V collagen and shown to be highly specific for separate, conformational dependent determinants within this molecule. When used for immunocytochemical tissue localization, these antibodies show that a major site for the in situ deposition of type V is within the extracellular matrices of many dense connective tissues. In these, however, it is largely in a form unavailable to the antibodies, thus requiring a specific “unmasking” treatment to obtain successful immunocytochemical staining. The specificity of these two IgG antibodies was determined by inhibition ELISA, in which only type V and no other known collagen shows inhibition. In ELISA, mixtures of the two antibodies give an additive binding reaction to the collagen, suggesting that each is against a different antigenic determinant. That both antigenic determinants are conformational dependent, being either in, or closely associated with, the collagen helix is demonstrated by the loss of antibody binding to molecules that have been thermally denatured. The temperature at which this occurs, as assayed by inhibition ELISA, is very similar to that at which the collagen helix melts, as determined by optical rotation. This gives strong additional evidence that the antibodies are directed against the collagen. The antibodies were used for indirect immunofluorescence analyses of cryostat sections of corneas and other organs from 17 to 18-day-old chick embryos. Of all tissues examined only Bowman’s membrane gave a strong staining reaction with cryostat sections of unfixed material. Staining in other areas of the cornea and in other tissues was very light or nonexistent. When, however, sections were pretreated with pepsin dissolved in dilute HAc or, surprisingly, with the dilute HAc itself dramatic new staining by the antibodies was observed in most tissues examined. The staining, which was specific for the anti-type V collagen antibodies, was largely confined to extracellular matrices of dense connective tissues. Experiments using protease inhibitors suggested that the “unmasking” did not involve proteolysis. We do not yet know the mechanism of this unmasking; however, one possibility is that the dilute acid causes swelling or conformational changes in a type-V collagen-containing supramolecular structure. Further studies should allow us to determine whether this is the case. 相似文献
79.
Ralf-Dieter Hilgers 《Biometrical journal. Biometrische Zeitschrift》1999,41(7):783-798
Component amount models were introduced by Piepel and Cornell (1985) to describe mixture experiments where the response depends not only on the proportions of the components but also on the total amount. The extended simplex centroid design supported by the barycenters corresponding to the regression functions in the model is D-optimal or fails to be D-optimal depending on the regression model under consideration. For two special component amount models, namely the ν-tic polynomial and the minimum polynomial of degree ν, the efficiency of the simplex centroid design was investigated. This covers the presentation of new results concerning the D-optimality as well as the assessment of the simplex centroid design in non-optimal situations by means of the G-efficiency. Formulae for the least squares estimates as well as their variances are presented. 相似文献
80.
Synergistic effects of two synthetic adjuvants, dimethyldioctadecylammonium bromide (DDA) and dextran sulfate (DXS) on the humoral response to sheep red blood cells (SRBC) were investigated. Mice received intraperitoneal (ip) injections of adjuvant and antigen simultaneously. The number of plaque-forming cells (PFC) in the spleen were determined 5 days later and circulating anti-SRBC antibodies were measured till 16 weeks after immunization. Although combinations of DDA and DXS were very effective in enhancing the PFC response to both moderate (2 X 10(7] and low (2 X 10(6] doses of SRBC, synergy between the adjuvants was only observed at the low dose of SRBC. Optimal augmentation of the primary response to the low antigen dose was evoked by the combination of the highest dose tested of either adjuvant (1 mumol DDA and 1 nmol DXS) resulting in a 560-fold increase of the number of PFC in the spleen as compared to controls. Even combinations of relatively small amounts of both adjuvants were very effective in augmenting the response to SRBC. Mice receiving half the amounts of both adjuvants with 2 X 10(6) SRBC displayed increased numbers of PFC in the spleen at Day 5 as well as increased titers of total anti-SRBC antibodies at Week 1 and Week 2 and 2-mercaptoethanol-resistant antibodies from Week 4 till Week 16 as compared to the calculated sum of responses in mice which received either DDA (0.05 mumol per mouse) or DXS (0.05 nmol per mouse). The mechanism behind the synergy between these adjuvants is discussed and the possibility of discerning adjuvants on their modes of action is suggested. 相似文献