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排序方式: 共有2236条查询结果,搜索用时 15 毫秒
61.
Raffaella Nenna MD Paola Papoff MD Corrado Moretti MD Daniela De Angelis MD Massimo Battaglia MD Stefano Papasso MD Mariangela Bernabucci MD Giulia Cangiano MD Laura Petrarca MD Serena Salvadei MD Ambra Nicolai MD Marianna Ferrara MD Enea Bonci MD Fabio Midulla MD 《Pediatric pulmonology》2014,49(9):919-925
62.
63.
Almasi B Rettenbacher S Müller C Brill S Wagner H Jenni L 《General and comparative endocrinology》2012,178(1):139-144
Hormones deposited in the avian egg are considered in many studies to influence or to adjust offspring phenotype to prevailing conditions in an adaptive way. Several studies demonstrated an effect of corticosterone, the main glucocorticoid in birds, injected into the egg on the developing chick, but the injection of steroids in the egg is far from mimicking the natural distribution of the hormone in the egg. Other studies applied a stressor or corticosterone to the mother. However it is still debated whether an increase of circulating corticosterone in the mother translates into higher concentrations of corticosterone in the egg. Therefore, we investigated in captive barn owls Tyto alba whether circulating corticosterone in egg-laying females elevated within a physiological range, resulted in the deposition of corticosterone in eggs. We found that an increase in circulating corticosterone in the mother within the naturally occurring range translated into elevated concentrations of corticosterone in the yolk of subsequently laid eggs, indicating a specific time frame and yolk layer of corticosterone deposition. We conclude that increasing maternal plasma corticosterone within a naturally occurring range is an efficient tool to increase corticosterone concentration in the egg and to manipulate conditions for the developing embryo. 相似文献
64.
Krone N Reisch N Idkowiak J Dhir V Ivison HE Hughes BA Rose IT O'Neil DM Vijzelaar R Smith MJ MacDonald F Cole TR Adolphs N Barton JS Blair EM Braddock SR Collins F Cragun DL Dattani MT Day R Dougan S Feist M Gottschalk ME Gregory JW Haim M Harrison R Olney AH Hauffa BP Hindmarsh PC Hopkin RJ Jira PE Kempers M Kerstens MN Khalifa MM Köhler B Maiter D Nielsen S O'Riordan SM Roth CL Shane KP Silink M Stikkelbroeck NM Sweeney E Szarras-Czapnik M Waterson JR Williamson L Hartmann MF Taylor NF 《The Journal of clinical endocrinology and metabolism》2012,97(2):E257-E267
65.
Galinato MG Kleingardner JG Bowman SE Alp EE Zhao J Bren KL Lehnert N 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(23):8896-8900
The active site of cytochrome c (Cyt c) consists of a heme covalently linked to a pentapeptide segment (Cys-X-X-Cys-His), which provides a link between the heme and the protein surface, where the redox partners of Cyt c bind. To elucidate the vibrational properties of heme c, nuclear resonance vibrational spectroscopy (NRVS) measurements were performed on (57)Fe-labeled ferric Hydrogenobacter thermophilus cytochrome c(552), including (13)C(8)-heme-, (13)C(5)(15)N-Met-, and (13)C(15)N-polypeptide (pp)-labeled samples, revealing heme-based vibrational modes in the 200- to 450-cm(-1) spectral region. Simulations of the NRVS spectra of H. thermophilus cytochrome c(552) allowed for a complete assignment of the Fe vibrational spectrum of the protein-bound heme, as well as the quantitative determination of the amount of mixing between local heme vibrations and pp modes from the Cys-X-X-Cys-His motif. These results provide the basis to propose that heme-pp vibrational dynamic couplings play a role in electron transfer (ET) by coupling vibrations of the heme directly to vibrations of the pp at the protein-protein interface. This could allow for the direct transduction of the thermal (vibrational) energy from the protein surface to the heme that is released on protein/protein complex formation, or it could modulate the heme vibrations in the protein/protein complex to minimize reorganization energy. Both mechanisms lower energy barriers for ET. Notably, the conformation of the distal Met side chain is fine-tuned in the protein to localize heme-pp mixed vibrations within the 250- to 400-cm(-1) spectral region. These findings point to a particular orientation of the distal Met that maximizes ET. 相似文献
66.
Deep vein thrombosis (DVT) is a major health problem that requires improved prophylaxis and treatment. Inflammatory conditions such as infection, cancer, and autoimmune diseases are risk factors for DVT. We and others have recently shown that extracellular DNA fibers produced in inflammation and known as neutrophil extracellular traps (NETs) contribute to experimental DVT. NETs stimulate thrombus formation and coagulation and are abundant in thrombi in animal models of DVT. It appears that, in addition to fibrin and von Willebrand factor, NETs represent a third thrombus scaffold. Here, we review how NETs stimulate thrombosis and discuss known and potential interactions of NETs with endothelium, platelets, red blood cells, and coagulation factors and how NETs could influence thrombolysis. We propose that drugs that inhibit NET formation or facilitate NET degradation may prevent or treat DVT. 相似文献
67.
68.
Lara Bellardita Tiziana Rancati Maria Francesca Alvisi Daniela Villani Tiziana Magnani Cristina Marenghi Nicola Nicolai Giuseppe Procopio Sergio Villa Roberto Salvioni Riccardo Valdagni 《European urology》2013
Background
Active surveillance (AS) is emerging as an alternative approach to limit the risk of overtreatment and impairment of quality of life (QoL) in patients with low-risk localised prostate cancer. Although most patients report high levels of QoL, some men may be distressed by the idea of living with untreated cancer.Objective
To identify factors associated with poor QoL during AS.Design, setting, and participants
Between September 2007 and March 2012, 103 patients participated in the Prostate Cancer Research International Active Surveillance (PRIAS) QoL study. Mental health (Symptom Checklist-90), demographic, clinical, and decisional data were assessed at entrance in AS. Health-related QoL (HRQoL) Functional Assessment of Cancer Therapy-Prostate version and Mini-Mental Adjustment to Cancer outcomes were assessed after 10 mo of AS.Outcome measurements and statistical analysis
Multivariate logistic regression models were used to identify predictors of low (<25th percentile) HRQoL, adjustment to cancer, and a global QoL index at 10 mo after enrolment.Results and limitations
The mean age of the study patients was 67 yr (standard deviation: ±7 yr). Lack of partner (odds ratio [OR]: 0.08; p = 0.009) and impaired mental health (OR: 1.2, p = 0.1) were associated with low HRQoL (p = 0.006; area under the curve [AUC]: 0.72). The maladaptive adjustment to cancer (p = 0.047; AUC: 0.60) could be predicted by recent diagnosis (OR: 3.3; p = 0.072). Poor global QoL (overall p = 0.02; AUC: 0.85) was predicted by impaired mental health (OR: 1.16; p = 0.070) and time from diagnosis to enrolment in AS <5 mo (OR: 5.52; p = 0.009). Influence of different physicians on the choice of AS (OR: 0.17; p = 0.044), presence of a partner (OR: 0.22; p = 0.065), and diagnostic biopsy with >18 core specimens (OR: 0.89; p = 0.029) were predictors of better QoL. Limitations of this study were the small sample size and the lack of a control group.Conclusions
Factors predicting poor QoL were lack of a partner, impaired mental health, recent diagnosis, influence of clinicians and lower number of core samples taken at diagnostic biopsy. Educational support from physicians and emotional/social support should be promoted in some cases to prevent poor QoL. 相似文献69.
Michael Untch Bernd Gerber Nadia Harbeck Christian Jackisch Norbert Marschner Volker M?bus Gunter von Minckwitz Sibylle Loibl Matthias W. Beckmann Jens-Uwe Blohmer Serban-Dan Costa Thomas Decker Ingo Diel Thomas Dimpfl Wolfgang Eiermann Tanja Fehm Klaus Friese Fritz J?nicke Wolfgang Janni Walter Jonat Marion Kiechle Uwe K?hler Hans-Joachim Lück Nicolai Maass Kurt Possinger Achim Rody Anton Scharl Andreas Schneeweiss Christoph Thomssen Diethelm Wallwiener Anja Welt 《Breast care (Basel, Switzerland)》2013,8(3):221-229
Zusammenfassung
Alle zwei Jahre findet in St. Gallen (Schweiz) die internationale Konsensuskonferenz zur Behandlung des primären Mammakarzinoms statt. Da sich das internationale Panel in St. Gallen aus Experten unterschiedlicher Länder zusammensetzt, spiegelt der Konsensus ein internationales Meinungsbild wider. Vor diesem Hintergrund erscheint es aus deutscher Sicht sinnvoll, die Abstimmungsergebnisse für den Therapiealltag in Deutschland zu konkretisieren. Eine deutsche Arbeitsgruppe mit acht Brustkrebsexperten, von denen zwei Mitglieder des internationalen St. Gallen-Panels sind, hat daher die Abstimmungsergebnisse der St. Gallen-Konsensuskonferenz (2013) für den Klinikalltag in Deutschland kommentiert. Inhaltliche Schwerpunkte der diesjährigen St. Gallen-Konferenz waren operative Fragestellungen der Brust und der Axilla, strahlentherapeutische und systemische Therapieoptionen sowie die klinische Relevanz der Tumorbiologie. Intensiv diskutiert wurde der klinische Einsatz von Multigen-Assays, inkl. ihrer Bedeutung für die individuelle Therapieentscheidung. 相似文献70.
Grete Andersen MD Mette C. Ørngreen MD Nicolai Preisler MD Eskild Colding‐J⊘rgensen MD Torben Clausen MD PhD Morten Duno PhD Tina D. Jeppesen MD John Vissing MD PhD 《Muscle & nerve》2013,47(3):409-415
Introduction: The pathogenesis of muscle involvement in patients with myotonic dystrophy type 1 (DM1) is not well understood. In this study, we characterized the muscle phenotype in patients with confirmed DM1. Methods: In 38 patients, muscle strength was tested by hand‐held dynamometry. Myotonia was evaluated by a handgrip test and by analyzing the decrement of the compound muscle action potential. Muscle biopsies were assessed for morphological changes and Na+‐K+ pump content. Results: Muscle strength correlated with a decline in Na+‐K+ pump content (r = 0.60, P < 0.001) and with CTG expansion. CTG expansion did not correlate with severity of myotonia, proximal histopathological changes, or Na+‐K+ pump content. Histopathologically, we found few centrally placed nuclei (range 0.2–6.9%). Conclusions: The main findings of this study are that muscle weakness correlated inversely with CTG expansion and that central nuclei are not a prominent feature of proximal muscles in DM1. Muscle Nerve 47:409‐415, 2013 相似文献