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51.
52.
Background
The diversity of parasites attacking a host varies substantially among different host species. Understanding the factors that explain these patterns of parasite diversity is critical to identifying the ecological principles underlying biodiversity. Seabirds (Charadriiformes, Pelecaniformes and Procellariiformes) and their ectoparasitic lice (Insecta: Phthiraptera) are ideal model groups in which to study correlates of parasite species richness. We evaluated the relative importance of morphological (body size, body weight, wingspan, bill length), life-history (longevity, clutch size), ecological (population size, geographical range) and behavioural (diving versus non-diving) variables as predictors of louse diversity on 413 seabird hosts species. Diversity was measured at the level of louse suborder, genus, and species, and uneven sampling of hosts was controlled for using literature citations as a proxy for sampling effort. 相似文献53.
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David Ochoa Mindaugas Jonikas Robert T Lawrence Bachir El Debs Joel Selkrig Athanasios Typas Judit Villén Silvia DM Santos Pedro Beltrao 《Molecular systems biology》2016,12(12)
The coordinated regulation of protein kinases is a rapid mechanism that integrates diverse cues and swiftly determines appropriate cellular responses. However, our understanding of cellular decision‐making has been limited by the small number of simultaneously monitored phospho‐regulatory events. Here, we have estimated changes in activity in 215 human kinases in 399 conditions derived from a large compilation of phosphopeptide quantifications. This atlas identifies commonly regulated kinases as those that are central in the signaling network and defines the logic relationships between kinase pairs. Co‐regulation along the conditions predicts kinase–complex and kinase–substrate associations. Additionally, the kinase regulation profile acts as a molecular fingerprint to identify related and opposing signaling states. Using this atlas, we identified essential mediators of stem cell differentiation, modulators of Salmonella infection, and new targets of AKT1. This provides a global view of human phosphorylation‐based signaling and the necessary context to better understand kinase‐driven decision‐making. 相似文献
56.
Rapid isolation of DNA from complex biological samples using a novel capture reagent--methidium-spermine-sepharose. 总被引:1,自引:0,他引:1
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We have synthesized and analyzed the functional properties of a novel DNA capture reagent containing a methidium moiety attached to a sepharose bead by a spermine linker. DNA present in a biological fluid or other complex sample binds to the reagent. The DNA-capture reagent complex is then separated from the sample by centrifugation and the DNA is released from the reagent by brief incubation in 0.1 to 0.5 N NaOH or KOH. Capture of DNA from complex samples is independent of the salt concentration of the sample, and occurs in the presence of high concentrations of EDTA, proteinase K and detergents. Many samples can be processed simultaneously. The following specific applications, in which denatured DNA is quantitated or characterized, are demonstrated: 1). Isolation of hepatitis B virus DNA from serum and quantitation by dot-blot hybridization, 2). Isolation and quantitation of DNA from urine, 3). Isolation of human genomic DNA from one microliter of blood or 100 HeLa cells followed by amplification of a specific gene sequence using the Polymerase Chain Reaction, 4). Isolation of single stranded phage M13 sequencing templates from bacterial cultures. These investigations suggest that a capture reagent containing an intercalating moiety bound to a solid support may be useful for many applications in molecular biology and molecular diagnostics. 相似文献
57.
J C Cooper A J Nicholls J M Simms M M Platts C B Brown A G Johnson 《BMJ (Clinical research ed.)》1983,286(6382):1923-1924
Four patients receiving continuous ambulatory peritoneal dialysis presented with scrotal or labial oedema but no detectable cough impulse. Two of the patients later developed clinical evidence of inguinal hernia, and in the other two inguinal hernias were found at operation. These cases suggest that genital oedema occurring in a patient receiving continuous ambulatory peritoneal dialysis is a sign of a small inguinal hernia which may not be detectable clinically. 相似文献
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Structural gene for the alkaline extracellular protease of Saccharomycopsis lipolytica. 总被引:6,自引:3,他引:3
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Mutants for Saccharomycopsis lipolytica temperature sensitive for alkaline extracellular protease production, but not for growth, were isolated. Thirty-three isolates were temperature sensitive for protease production, and one (xpr-32) produced a temperature-sensitive protease. Genetic analysis indicated that xpr-32 was located in gene XPR2, and allele xpr2-7 was found to also produce a temperature-sensitive protease. None of five independently isolated xpr2 mutations affects the production of extracellular ribonucleases and acid protease(s). Diploids with zero, one, or two active alleles of the XPR2 locus were constructed, and the XPR2 locus was shown to exhibit a gene dosage effect on alkaline extracellular protease synthesis (enzyme activity/cell protein). These results suggest that the XPR2 gene is the structural gene for the alkaline extracellular protease of S. lipolytica. 相似文献
60.
Increasing workloads in our radiology department prompted a study of casualty officers'' use of x ray examinations, of which there were 5463 in the period. While casualty officers were in post referrals for x ray examination did not become more selective, but skills in interpreting films improved. Overall, 4.9% of trauma radiographs were misinterpreted, but this fell from 7.1% to 2.9% during tenure of post. One in four errors was clinically important. Clinical guidelines for selective radiography produced a significant and sustained reduction in the number of x ray examinations requested by the department. Analysis of one common injury indicated that the quality of patient care was not adversely affected. The number of x ray examinations carried out in the accident and emergency department can be reduced by using guidelines, and this does not compromise the quality of patient care. Appreciable savings may be made in patients'' waiting times and radiodiagnostic expenditure. 相似文献