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321.
We describe a 50-year-old man with adult T-cell leukemia complicated by laryngeal tuberculosis whose tumor cells proliferate in response to IL-2 in a paracrine manner. On admission, the patient's white blood cell count was 17,900/mm3; 73% were abnormal lymphocytes with convoluted nuclei. FACS analysis showed that the tumor cells were CD4-negative, CD8-positive T cells. Southern blot analysis of tumor cells revealed integration of a defective HTLV-I genome lacking gag and pol genes. He was diagnosed with chronic ATL complicated by laryngeal tuberculosis. The primary leukemic cells expressed IL-2R alpha and IL-2R beta detected by FACS and Northern blot analysis and showed marked growth in response to exogenously added recombinant IL-2 in short-term cultures. Northern blot analysis did not show any IL-2 mRNA. We have previously demonstrated that primary leukemic cells from some ATL patients grow in response to IL-2 in an autocrine or paracrine manner. These results suggest that in CD8 ATL, IL-2 may be involved in a paracrine manner.  相似文献   
322.
Einfluß der Mittelspannung auf das Wechselverformungsverhalten. Wechselverformungskurve, Mitteldehnungs-Lastspielzahl-Kurve. Einfluß von Änderungen der Mittelspannung auf das Wechselverformungsverhalten. Probenabmessungsänderungen. Rückverformung nach Mittelspannungsänderung. Versetzungsmodell zur Deutung der Versuchsergebnisse.  相似文献   
323.
Zug-Druck-Wechselversuche an unlegierten normalgeglühten Stählen mit 0,1 bis 1,15%C. Ermittlung der Wechselverformungskurven. Spannungsoptische Untersuchung während der Ermüdungsbeanspruchung. Inhomogene plastische Deformation. Ausbreitung von Ermüdungs-Lüders-Bändern. Bewertung des Wechselverformungsverhaltens während der Wechselver- und -entfestigung.  相似文献   
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326.
Mutschke  Peter  Mayr  Philipp  Schaer  Philipp  Sure  York 《Scientometrics》2011,89(1):349-364
The paper introduces scholarly Information Retrieval (IR) as a further dimension that should be considered in the science modeling debate. The IR use case is seen as a validation model of the adequacy of science models in representing and predicting structure and dynamics in science. Particular conceptualizations of scholarly activity and structures in science are used as value-added search services to improve retrieval quality: a co-word model depicting the cognitive structure of a field (used for query expansion), the Bradford law of information concentration, and a model of co-authorship networks (both used for re-ranking search results). An evaluation of the retrieval quality when science model driven services are used turned out that the models proposed actually provide beneficial effects to retrieval quality. From an IR perspective, the models studied are therefore verified as expressive conceptualizations of central phenomena in science. Thus, it could be shown that the IR perspective can significantly contribute to a better understanding of scholarly structures and activities.  相似文献   
327.
Many PCR-techniques have already been published for the detection of thermophilic Campylobacters. In order to provide a practical overview for the user – without laying claim to completeness – we present a collection of actual PCR detection methods, some of them were modified and some are still unpublished. They are listed along with their target genes and specificities. Four conventional and seven real-time PCR methods were tested and compared using a panel of 65 Campylobacter strains belonging to 12 different more or less related species. The regular PCR methodes tested include the 16S rRNA gene based technique that specifically detects C. jejuni, C. coli and C. lari without differenciating to species level, two flaA gene based typing-methods, one for C. jejuni and C. coli in combination, which was slightly modified according to Nachamkin et al. (1993, 1996), and additionally for C. lari. Another duplex PCR was carried out which allows identification of the two species C. jejuni and C. coli simultaneously. Among the real-time methods tested there were three techniques allowing identification of C. jejuni alone, two assays based on the flagellin A gene capable to identify C. jejuni and C. coli in combination, a duplex PCR performed as triplex PCR combined with an internal amplification control that detected C. jejuni and C. coli separately, and a Lightcycler method that detected C. jejuni, C. coli and C. lari simultaneously. Inclusivity and exclusivity were shown for each of the methods. In most cases inclusivity was good, but some techniques raised problems concerning exclusivity. Flagellin based real-time PCR techniques partially crossreacted either with C. lari or C. upsaliensis. C. hyoilei which is very closely related to C. coli reacted in almost all methods applied like C. coli.
Zusammenfassung: Eine Vielzahl von PCR-Nachweismethoden für Campylobacter jejuni und C. coli wurden bereits publiziert. Hier wird eine Zusammenfassung von aktuellen PCR-Nachweismethoden für thermophile Campylobacter spp. pr?sentiert, die dem Anwender exemplarisch eine schnelle tabellarische übersicht über aktuelle Methoden bietet sowie über deren Zielgene und Spezifit?ten. Es wurden vier konventionelle und sieben Real-Time PCR-Methoden zur Identifizierung von Campylobacter spp. verglichen. Bei den konventionellen Methoden handelt es sich um eine auf dem 16S rRNA-Gen basierende PCR, die spezifisch mit C. jejuni, C. coli und C. lari reagiert, zwei auf dem Flagellin-Gen beruhende PCR-Typisierungsmethoden, die in modifizierter Form für C. jejuni, C. coli und zus?tzlich für C. lari durchgeführt wurden. Als vierte Methode wurde eine Duplex-PCR zur Identifzierung von C. jejuni und C. coli mit einbezogen. Unter den getesteten Real-Time PCR-Methoden befanden sich drei 5′-Nuklease Assays, die spezifisch C. jejuni detektieren, zwei Assays, die auf dem Flagellin-Gen beruhen und C. jejuni und C. coli gemeinsam erfassen, eine Duplex-PCR, die C. jejuni (mapA-Gen) und C. coli (ceu-EGen) identifizieren kann und noch mit einer unver?ffentlichten internen Kontrolle kombiniert wurde, sowie eine Lightcycler-Methode, die auf dem 16S rRNA-Gen basiert und C. jejuni, C. coli und C. lari gemeinsam detektiert, aber nicht differenziert. Die Methoden sind entweder unver?ndert aus Publikationen übernommen oder auch nach Datenbankanalysen modifziert worden. Zum Testen wurden 65 Campylobacter-St?mme aus 12 verschiedenen Spezies eingesetzt. Die Inklusivit?t war insgesamt bei allen Methoden sehr gut, bei der Exklusivit?t gab es Unsicherheiten. Real-Time PCR-Methoden, die auf dem Flagellin-Gen beruhen, k?nnen in manchen F?llen die verwandten Arten C. lari oder C. upsaliensis mit erfassen. Der enge Verwandte C. hyoilei wird in fast allen F?llen gleichzeitig mit C. coli detektiert.

Eingegangen: 31. Januar 2007  相似文献   
328.
The aim of this paper is to examine the effects of crime on regional economic growth in Mexico. We estimate a growth model using a spatial panel data model and test for the presence and type of spatial interaction, as proposed by Elhorst. Our results suggest that a two‐way spatial Durbin model best fits the data, crime exerts a negative total effect on economic growth across Mexican states, particularly homicides and robbery, and significant spillover effects seem to reinforce the negative impact on regional growth.  相似文献   
329.
A 5′ nuclease duplex real-time polymerase chain reaction (PCR) assay was developed and validated with various food products for the specific and fast detection of Salmonella spp. in food. The assay used previously published primers in combination with a newly developed probe targeting the invA gene. An internal amplification control, which is coamplified in a duplex PCR, was included in the assay. The analysis of 1,934 natural food samples with real-time PCR and the cultural method in parallel resulted in a relative accuracy of 100% and 99.84% respectively, depending on the enrichment procedure in which buffered peptone water and selective enrichment in Rappaport–Vassiliadis (RV) broth were employed. The duplex real-time PCR assay has proven to be a specific, sensitive and fast screening method for Salmonella spp. in food. The overall analysis time of the PCR method was approximately 28 h, in contrast to 4 to 5 days with conventional Salmonella diagnostics. The developed assay has been shown to be a reliable diagnostic tool for use in routine analysis. It has been validated thoroughly and has become an official method in Germany for the detection of Salmonella spp. in food.  相似文献   
330.

Optical character recognition (OCR) has proved a powerful tool for the digital analysis of printed historical documents. However, its ability to localize and identify individual glyphs is challenged by the tremendous variety in historical type design, the physicality of the printing process, and the state of conservation. We propose to mitigate these problems by a downstream fine-tuning step that corrects for pathological and undesirable extraction results. We implement this idea by using a joint energy-based model which classifies individual glyphs and simultaneously prunes potential out-of-distribution (OOD) samples like rubrications, initials, or ligatures. During model training, we introduce specific margins in the energy spectrum that aid this separation and explore the glyph distribution’s typical set to stabilize the optimization procedure. We observe strong classification at 0.972 AUPRC across 42 lower- and uppercase glyph types on a challenging digital reproduction of Johannes Balbus’ Catholicon, matching the performance of purely discriminative methods. At the same time, we achieve OOD detection rates of 0.989 AUPRC and 0.946 AUPRC for OOD ‘clutter’ and ‘ligatures’ which substantially improves upon recently proposed OOD detection techniques. The proposed approach can be easily integrated into the postprocessing phase of current OCR to aid reproduction and shape analysis research.

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