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121.
122.
Purpose: Established diagnostic thresholds for high-sensitivity cardiac troponins (hs-cTn) might not apply for elderly patients as they are elevated irrespective of the presence of an acute myocardial infarction (AMI). Aim of the present study was to investigate hs-cTnI in elderly patients with suspected AMI and to calculate optimized diagnostic cutoffs.

Material and methods: Data from a prospective multi-centre study and from a second independent prospective single-centre cohort study were analysed. A number of 2903 patients were eligible for further analysis. Patients > 70 years were classified as elderly. hs-cTnI was measured upon admission.

Results: Around 34.7% of 2903 patients were classified as elderly. Around 22.5% of elderly patients were finally diagnosed with AMI. Elderly patients had higher hs-cTnI levels at admission irrespective of the final diagnosis (p?<?0.001). According to the AUROC, hs-cTnI was a strong marker for detection of AMI in elderly patients. Application of the 99th percentile cutoffs showed a substantially lower specificity in elderly. By using optimized thresholds, specificity was improved to levels as in younger patients in both cohorts but accompanied with a decrease in sensitivity.

Conclusions: hs-cTnI levels have a lower specificity for detecting AMI in elderly patients. This lower specificity can be improved by using hs-cTnI thresholds optimized for elderly patients.  相似文献   

123.
Recent pathogenomic research on plant parasitic oomycete effector function and plant host responses has resulted in major conceptual advances in plant pathology, which has been possible thanks to the availability of genome sequences.  相似文献   
124.
Ohne ZusammenfassungMeinem verehrten Lehrer, Herrn Prof. E.Hadorn, möchte ich auch an dieser Stelle danken für die Anregung zu dieser Arbeit und die Unterstützung, die er ihr hat angedeihen lassen. Auch Herrn Prof. F.Baltzer, Bern, der mich in die entwicklungsphysiologische Technik einführte und Herrn Prof. J.Brachet, Brüssel, in dessen Laboratorium mir die Möglichkeit geboten wurde, biochemische Methoden kennenzulernen, möchte ich für ihre Bemühungen und ihr Wohlwollen meinen Dank aussprechen.  相似文献   
125.
Central corneal thickness (CCT) has become an endophenotype of major interest for the genetically complex disorder glaucoma. CCT has a high heritability, and thin CCT is an independent risk factor for the diagnosis and progression of open-angle glaucoma. Genome-wide association studies thus provide genetic loci associated with CCT and potentially related to open-angle glaucoma. The distribution of CCT and prevalence of glaucoma in population-based studies have demonstrated ethnic differences suggesting ethnic-dependent variations in the genetic determinants of CCT. We conducted a genome-wide association study in Caucasians (n?=?3,931) from the Gutenberg Health Study (Germany) followed by replication of 30 genome-wide significant SNPs or SNPs of interest (P?<?10?5) in the Rotterdam Study (The Netherlands, n?=?1,418). In a combined analysis, we confirmed quantitative trait loci on chromosomes 9q34 and 16q24 for association with CCT. On chromosome 16q24, the locus is located in an intergenic region near the ZNF469 gene (top SNP: rs9938149, P?=?1.45?×?10?12). ZNF469 missense mutation is involved in a syndrome with very thin cornea (brittle cornea syndrome). The second locus on chromosome 9q34 represents the intergenic region between the RXRA and COL5A1 gene (top SNP: rs3132306, P?=?2.71?×?10?10). Collagen type 5 determines the diameter of the corneal collagen fibrils. In our Caucasian population-based GWA study, we reinforce the involvement of collagen-related genes influencing CCT in Caucasians. We could not confirm the collagen type 8 locus on chromosome 1 as reported in Asian studies.  相似文献   
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127.
The occurrence and distribution of seedling resistance genes and the presence of adult plant resistance to powdery mildew, was investigated in a collection of 155 Nordic bread wheat landraces and cultivars by inoculation with 11 powdery mildew isolates. Eighty-nine accessions were susceptible in the seedling stage, while 66 accessions showed some resistance. Comparisons of response patterns allowed postulation of combinations of genes Pm1a, Pm2, Pm4b, Pm5, Pm6, Pm8 and Pm9 in 21 lines. Seedling resistance was three times more frequent in spring wheat than in winter wheat. The most commonly postulated genes were Pm1a+Pm2+Pm9 in Sweden, Pm5 in Denmark and Norway, and Pm4b in Finland. Forty-five accessions were postulated to carry only unidentified genes or a combination of identified and unidentified genes that could not be resolved by the 11 isolates. Complete resistance to all 11 isolates was present in 18 cultivars. Adult plant resistance was assessed for 109 accessions after natural infection with a mixture of races. In all, 92% of the accessions developed less than 3-5% pathogen coverage while nine lines showed 10-15% infected leaf surface. The characterization of powdery mildew resistance in Nordic wheat germplasm could facilitate the combination of resistance genes in plant breeding programmes to promote durability of resistance and disease management.  相似文献   
128.
Zusammenfassung Es wurden in der vorliegenden Arbeit Methoden ausgearbeitet, die einen raschen mikrochemischen Nachweis des Cholins ermöglichen. Mit diesen Methoden wurden über 100 Spezies aus den verschiedensten Pflanzenfamilien auf ihren Cholingehalt sowie auf den Cholingehalt ihrer Organe geprüft und es wurde das Cholin überall, in Stengeln, Blättern, Blüten, Holz, Rinde, Wurzeln usw. gefunden. Kein Cholin wurde nur in den drei untersuchten Flechten (Evernia prunastri, Parmelia sulcata undParmelia perforata) gefunden.Orientierende Versuche über die Veränderungen des Cholingehaltes von keimenden Samen und von Blättern im Laufe einer Nacht geben Anhaltspunkte für starke physiologische Verschiebungen im Cholingehalt.Nach Beendigung der Ausarbeitung einer quantitativen Methode zur Bestimmung von Cholin in kleinen Mengen Ausgangsmaterial sollen die angedeuteten Fragen auf exakter quantitativer Grundlage näher untersucht werden.  相似文献   
129.
Epstein-Barr virus (EBV) replicates its genome as a licensed plasmid in latently infected cells. Although replication of this plasmid is essential for EBV latent infection, its synthesis still fails for 16% of the templates in S phase. In order to understand these failures, we sought to determine whether the affinity of the initiator protein (EBNA1) for its binding sites in the origin affects the efficiency of plasmid replication. We have answered this question by using several engineered origins modeled upon the arrangement of EBNA1-binding sites found in DS, the major plasmid origin of EBV. The human TRF2 protein also binds to half-sites in DS and increases EBNA1's affinity for its own sites; we therefore also tested origin efficiency in the presence or absence of these sites. We have found that if TRF2-half-binding sites are present, the efficiency of supporting the initiation of DNA synthesis and of establishing a plasmid bearing that origin directly correlates with the affinity of EBNA1 for that origin. Moreover, the presence of TRF2-half-binding sites also increases the average level of EBNA1 and ORC2 bound to those origins in vivo, as measured by chromatin immunoprecipitation. Lastly, we have created an origin of DNA synthesis from high-affinity EBNA1-binding sites and TRF2-half-binding sites that functions severalfold more efficiently than does DS. This finding indicates that EBV has selected a submaximally efficient origin of DNA synthesis for the latent phase of its life cycle. This enhanced origin could be used practically in human gene vectors to improve their efficiency in therapy and basic research.  相似文献   
130.
Fusarium species from agricultural crops have been well studied with respect to toxin production and genetic diversity, while similar studies of communities from nonagricultural plants are much more limited. We examined 72 Fusarium isolates from a native North American tallgrass prairie and found that Gibberella intermedia (Fusarium proliferatum), Gibberella moniliformis (Fusarium verticillioides), and Gibberella konza (Fusarium konzum) dominated. Gibberella thapsina (Fusarium thapsinum) and Gibberella subglutinans (Fusarium subglutinans) also were recovered, as were seven isolates that could not be assigned to any previously described species on the basis of either morphological or molecular characters. In general, isolates from the prairie grasses produced the same toxins in quantities similar to those produced by isolates of the same species recovered from agricultural hosts. The G. konza isolates produce little or no fumonisins (up to 120 μg/g by one strain), and variable but generally low to moderate amounts of beauvericin (4 to 320 μg/g) and fusaproliferin (50 to 540 μg/g). Toxicity to Artemia salina larvae within most species was correlated with the concentration of either beauvericin or fusaproliferin produced. Organic isolates from some cultures of G. moniliformis were highly toxic towards A. salina even though they produced little, if any, beauvericin or fusaproliferin. Thus, additional potentially toxigenic compounds may be synthesized by G. moniliformis strains isolated from prairie grasses. The Fusarium community from these grasses appears to contain some species not found in surrounding agricultural communities, including some that probably are undescribed, and could be capable of serving as a reservoir for strains of potential agricultural importance.  相似文献   
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