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21.
Tanja Vogel Holly Boettger-Tong Indrajit Nanda Frank Dechend Alexander I. Agulnik Colin E. Bishop Michael Schmid Jorg Schmidtke 《Chromosome research》1998,6(1):35-40
Sequences homologous to human and bovine TSPY were isolated from M. musculus testicular cDNA, and a nearly full-length gene was polymerase chain reaction (PCR) amplified from mouse genomic DNA. This gene is apparently non-functional. Contrary to the situation encountered in species along the primate and artiodactyl lineages, in which TSPY is moderately repetitive, murine Tspy appears to be single copy. Murine Tspy is located on Yp, i.e. in the same syntenic group as in man. Sequence comparisons of murine, human and bovine TSPY exons suggest that TSPY became non-functional during rodent evolution. 相似文献
22.
Zabka TS Romano TA 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,273(1):636-647
The skin is an important tissue of the immune system; however, little is known about immune cells in dolphin skin, and very few cetacean-specific immunoreagents are available for investigative purposes. Therefore, in this study immunohistochemistry techniques were used with species-specific and non-species-specific antibodies to characterize immune cells, primarily focusing on Langerhans cells, in skin from the Atlantic bottlenose dolphin (Tursiops truncatus). An antibody to human major histocompatibility complex (MHC) class II molecules labeled cells with a dendritic-like morphology. The immunophenotype, morphology, and distribution of some of these cells are consistent with those of Langerhans cells. The cells were predominantly found in dermal papillae, primarily along the epidermal-dermal junction. Thus, the location of these cells was somewhat different from that in terrestrial mammals. Other MHC II (+) cells of varying morphology were observed deeper in the dermis, with a perivascular concentration, and had characteristics of macrophages and dermal dendritic cells. There was no immunostaining with cetacean-specific CD2 or CD21. In diseased skin, a subjective increase of MHC II (+) cells, most notably in the superficial skin layers, was associated with an ulcerative dermatitis. A few CD2 (+) cells were also present. Differences between dolphins and terrestrial mammals in terms of morphology, mechanisms of response to insult and repair, and environmental challenges may explain the modified distribution of MHC II (+) cells in dolphin skin. An elucidation of the immune cells in cetacean skin will contribute to our understanding of the evolution of functional adaptations to various environments, facilitate diagnosis of skin diseases, and define the potential for intradermal administration of vaccines and other immunotherapeutics. 相似文献
23.
Persistent organochlorines, sedentary occupation, obesity and human male subfertility 总被引:4,自引:0,他引:4
Magnusdottir EV Thorsteinsson T Thorsteinsdottir S Heimisdottir M Olafsdottir K 《Human reproduction (Oxford, England)》2005,20(1):208-215
BACKGROUND: Studies have suggested that the quality of human semen has been declining over recent decades, presumably because of lifestyle or environmental factors. METHODS: Polychlorinated biphenyls and organochlorine pesticides were analysed in the plasma of 25 men with poor semen quality, 20 men with normal semen quality and idiopathic subfertility and 27 men with normal semen quality and female factor subfertility. Samples of seminal fluid were also analysed to assess the relationship between the levels in blood and semen. RESULTS: The results indicate no difference in the levels of organochlorines between the groups. The levels of organochlorines in seminal fluid were proportional to the levels in plasma, but approximately 40 times lower. Men with poor semen quality were three times more likely to be obese than men with normal semen quality. There was also a significant negative correlation between semen quality parameters and body mass index among men with normal semen quality. The prevalence of sedentary work was lowest among men with the best semen quality. CONCLUSIONS: Poor semen quality was found to be associated with sedentary work and obesity but not with plasma levels of persistent organochlorines. More research is needed to assess whether sedentary lifestyle and obesity are causal factors in the decline of semen quality. 相似文献
24.
Influence of scaffold thickness and scaffold composition on bioartificial graft survival 总被引:13,自引:0,他引:13
Biological scaffolds exhibit advantageous properties for tissue engineering of small diameter vessels. The influence of their extracellular matrix (ECM) components during in vivo repopulation is unknown. We implanted different xenogenic vascular matrices in a rat model to determine the influence of scaffold-thickness and ECM composition on in vivo repopulation. Decellularized ovine jugular vein (JV, n=42), carotid artery (CA, n=42) and aorta (AO, n=42) were implanted subcutaneously in the neck of adult male rats. Animals were sacrificed 2, 4 and 8 weeks after implantation. Cell and matrix morphology of explanted scaffolds were characterized by hematoxylin-eosin and pentachrome staining. Monoclonal anti-rat-CD31 was used to identify revascularization. Quantification of cell density was done by DNA-isolation.THICKNESS OF IMPLANTED XENOGENIC SCAFFOLDS VARIED ACCORDING TO THE MATERIAL USED (AO: 3.0-3.8mm; CA: 0.7-0.88mm; JV: 0.35-0.61mm). Immunohistology revealed complete repopulation of AO, CA, and JV scaffolds with endothelial cells and myofibroblasts within 2 weeks. After 8 weeks of implantation, AO scaffolds were completely covered by an endothelial monolayer and showed signs of a central matrix degeneration. JV scaffolds were completely degenerated at this stage. In contrast, CA scaffolds showed preserved ECM with a normal myofibroblast population and endothelial cell coverage. 相似文献
25.
Juliane Menzel Klaus Abraham Gabriele I. Stangl Per Magne Ueland Rima Obeid Matthias B. Schulze Isabelle Herter-Aeberli Tanja Schwerdtle Cornelia Weikert 《Nutrients》2021,13(2)
Scientific evidence suggests that a vegan diet might be associated with impaired bone health. Therefore, a cross-sectional study (n = 36 vegans, n = 36 omnivores) was used to investigate the associations of veganism with calcaneal quantitative ultrasound (QUS) measurements, along with the investigation of differences in the concentrations of nutrition- and bone-related biomarkers between vegans and omnivores. This study revealed lower levels in the QUS parameters in vegans compared to omnivores, e.g., broadband ultrasound attenuation (vegans: 111.8 ± 10.7 dB/MHz, omnivores: 118.0 ± 10.8 dB/MHz, p = 0.02). Vegans had lower levels of vitamin A, B2, lysine, zinc, selenoprotein P, n-3 fatty acids, urinary iodine, and calcium levels, while the concentrations of vitamin K1, folate, and glutamine were higher in vegans compared to omnivores. Applying a reduced rank regression, 12 out of the 28 biomarkers were identified to contribute most to bone health, i.e., lysine, urinary iodine, thyroid-stimulating hormone, selenoprotein P, vitamin A, leucine, α-klotho, n-3 fatty acids, urinary calcium/magnesium, vitamin B6, and FGF23. All QUS parameters increased across the tertiles of the pattern score. The study provides evidence of lower bone health in vegans compared to omnivores, additionally revealing a combination of nutrition-related biomarkers, which may contribute to bone health. Further studies are needed to confirm these findings. 相似文献
26.
Matthias Lngin Bruno Reichart Stig Steen Trygve Sjberg Audrius Paskevicius Qiuming Liao Guangqi Qin Maren Mokelke Tanja Mayr Julia Radan Lara Issl Ines Buttgereit Jiawei Ying Ann Kathrin Fresch Alessandro Panelli Stefanie Egerer Andrea Bhr Barbara Kessler Anastasia Milusev Riccardo Sfriso Robert Rieben David Ayares Peter J. Murray Reinhard Ellgass Christoph Walz Nikolai Klymiuk Eckhard Wolf Jan‐Michael Abicht Paolo Brenner 《Xenotransplantation》2021,28(1):e12636
27.
Diana Lüftner Andreas D. Hartkopf Michael P. Lux Friedrich Overkamp Hans Tesch Adriana Titzmann Patrik Pschke Markus Wallwiener Volkmar Müller Matthias W. Beckmann Erik Belleville Wolfgang Janni Tanja N. Fehm Hans-Christian Kolberg Johannes Ettl Diethelm Wallwiener Andreas Schneeweiss Sara Y. Brucker Peter A. Fasching 《Breast care (Basel, Switzerland)》2021,16(2):108
BackgroundThe therapeutic armamentarium for patients with metastatic breast cancer is becoming more and more specific. Recommendations from clinical trials are not available for all treatment situations and patient subgroups, and it is therefore important to collect real-world data.SummaryTo develop recommendations for up-to-date treatments and participation in clinical trials for patients with metastatic breast cancer, the Prospective Academic Translational Research PRAEGNANT Network was established to optimize the quality of oncological care in the advanced therapeutic setting. The main aim of PRAEGNANT is to systematically record medical care for patients with metastatic breast cancer in the real-life setting, including the outcome and side effects of different treatment strategies, to monitor quality-of-life changes during therapy, to identify patients eligible for participation in clinical studies, and to allow targeted therapies based on the molecular structures of breast carcinomas.Key MessagesThis article describes the PRAEGNANT network and sheds light on the question of whether the various end points from clinical trials can be transferred to the real-world treatment situation. 相似文献
28.
Tanja Neupert Gabriele Ihorst Wilfried Karmaus Thomas Frischer Matthias Kopp Christel Ulmer Brigitte Schwöbel Johannes Forster Joachim Kühr 《Zeitschrift fur Gesundheitswissenschaften》1997,5(1):63-75
Conclusion
Geographical differences in morbidity of asthma and asthmalike complaints were ascertained and remained stable after adjustment for potential confounders. However, the choice of the way of presentation (relative risk versus deviation from the weighted mean of the prevalences) can provoke different suggestive effects. 相似文献29.
MR microcirculation assessment in cervical cancer: correlations with histomorphological tumor markers and clinical outcome. 总被引:8,自引:0,他引:8
N A Mayr H Hawighorst W T Yuh M Essig V A Magnotta M V Knopp 《Journal of magnetic resonance imaging : JMRI》1999,10(3):267-276
This article reviews the experience available to date on microcirculation assessment in cancer of the cervix including correlation studies of magnetic resonance (MR) microcirculatory parameters with histo-morphometric predictors and direct correlation with patient outcome. The data suggest that MR microcirculation parameters do not always correlate with histo-morphometric parameters, while there is evidence that MR parameters predict patients' treatment outcome. These observations raise the issue that perhaps the histo-morphometric parameters, accepted gold standards for tumor angiogenesis and prognostic factors, reflect anatomical information at a "static" single time point and may not always provide sufficient information on the "dynamic" microcirculation function of the tumor. MR microcirculation assessment reflects both anatomical and functional information and may provide this additional information on the "dynamic" angiogenic and metabolic status of a tumor. Therefore, assessment of tumor microcirculation may augment the individual risk profile in cervical cancer patients and has the potential to impact on therapy selection and treatment outcome. 相似文献
30.
One-hundred and eight-five pairs of gas samples were collected from inspired gas (10 cm behind the head at nose level) and end-tidal gas of persons administering anesthesia in 3 operating rooms during daily routine anesthesia. Mean operating-room N2O concentrations from 22 to 144 ppm (volume/volume [V/V]) were measured by gas chromatography, and large moment-to-moment variations (temporal gradients) were seen in individual operating rooms. Mean end-tidal N2O concentrations from 51 to 114 ppm (V/V) were observed. There were low correlations between inspired and end-tidal N2O concentrations (r values as low as r = 0.35). This poor relationship is presumably due to spatial and temporal gradients of N2O in the operating rooms. We conclude that the temporal and spatial gradients in N2O concentrations within active operating rooms are sufficiently large to invalidate estimation of exposure of anesthetic personnel to N2O from "spot" or "grab" samples collected in the breathing area. 相似文献