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81.
82.
Maltaris T Beckmann MW Mueller A Hoffmann I Kohl J Dittrich R 《Fertility and sterility》2007,87(1):195-197
This study evaluated the effect of gonadotropin stimulation on the primordial follicle reserve of cryopreserved human ovarian tissue after transplantation in severe combined immunodeficient mice. We found that prolonged gonadotropin stimulation significantly reduces primordial follicles. 相似文献
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84.
Michael S. Gold Patrick J. Quinn Dianne E. Campbell Jane Peake Joanne Smart Marnie Robinson Michael OSullivan Josef Korbinian Vogt Helle Krogh Pedersen Xiaoqiu Liu Elham Pazirandeh-Micol Ralf G. Heine 《Nutrients》2022,14(11)
This open-label, non-randomized, multicenter trial (Registration: ) aimed to assess if an amino acid-based formula (AAF) supplemented with two human milk oligosaccharides (HMO) supports normal growth and is well tolerated in infants with a cow’s milk protein allergy (CMPA). Term infants aged 1–8 months with moderate-to-severe CMPA were enrolled. The study formula was an AAF supplemented with 2′-fucosyllactose (2′-FL) and lacto-N-neotetraose (LNnT). Infants were fed the study formula for 4 months and were offered to remain on the formula until 12 months of age. Tolerance and safety were assessed throughout the trial. Out of 32 infants (mean age 18.6 weeks; 20 (62.5%) male), 29 completed the trial. During the 4-month principal study period, the mean weight-for-age Z score (WAZ) increased from –0.31 at the baseline to +0.28 at the 4-months’ follow-up. Linear and head growth also progressed along the WHO child growth reference, with a similar small upward trend. The formula was well tolerated and had an excellent safety profile. When comparing the microbiome at the baseline to the subsequent visits, there was a significant on-treatment enrichment in HMO-utilizing bifidobacteria, which was associated with a significant increase in fecal short-chain fatty acids. In addition, we observed a significant reduction in the abundance of fecal Proteobacteria, suggesting that the HMO-supplemented study formula partially corrected the gut microbial dysbiosis in infants with CMPA. NCT 03661736相似文献
85.
Stephan Bechtel Rouven Schweitzer Maximilian Frey Ralf Busch Hans-Georg Herrmann 《Materials》2022,15(9)
Generating polymer–metal structures by means of additive manufacturing offers huge potential for customized, sustainable and lightweight solutions. However, challenges exist, primarily with regard to reliability and reproducibility of the additively generated joints. In this study, the polymers ABS, PETG and PLA, which are common in material extrusion, were joined to grit-blasted aluminum substrates. Temperature dependence of polymer melt rheology, wetting and tensile single-lap-shear strength were examined in order to obtain appropriate thermal processing conditions. Joints with high adhesive strength in the fresh state were aged for up to 100 days in two different moderate environments. For the given conditions, PETG was most suitable for generating structural joints. Contrary to PETG, ABS–aluminum joints in the fresh state as well as PLA–aluminum joints in the aged state did not meet the demands of a structural joint. For the considered polymers and processing conditions, this study implies that the suitability of a polymer and a thermal processing condition to form a polymer–aluminum joint by material extrusion can be evaluated based on the polymer’s rheological properties. Moreover, wetting experiments improved estimation of the resulting tensile single-lap-shear strength. 相似文献
86.
Nocturnal activation of melatonin receptor type 1 signaling modulates diurnal insulin sensitivity via regulation of PI3K activity 下载免费PDF全文
87.
Christina Maria Steger Johannes Bonatti Ralf Joachim Rieker Nikolaos Bonaros Thomas Schachner 《Experimental and toxicologic pathology》2017,69(8):598-604
Although still a matter of controversial discussion, skeletal myoblasts are one of the options for stem cell transplantation improving cardiac function after myocardial infarction, exhibiting several advantages including the availability, the ability of self-renewal and differentiation, and the lack of ethical and immunological problems. The aim of this study was to investigate the impact of stem cell therapy with skeletal myoblasts on experimental venous bypass grafts in a mouse model of vein graft disease.Forty C57BL/6J mice underwent bypass grafting interposing a venous bypass graft of the donor mouse into the carotid artery of the recipient mouse.Twenty mice received periadventitially treatment with 1 million fluorescence labeled skeletal myoblasts suspended in culture medium (treatment group), the other twenty mice received only culture medium without myoblasts (control group).Two weeks after bypass surgery, the vein grafts of all 40 mice were harvested, stained and histologically investigated under light and immunofluorescence microscope.Against our expectations, skeletal myoblasts stayed in place and were still located in the adventitia after bypass grafting. Additionally, vein grafts of the myoblast group revealed a 2fold increased neoneointima formation, a decreased media thickness, a slightly increased neovascularization, a higher percentage of reendothelialization and also a slightly higher percentage of PDGFR ɑ, PDGFR ß, MMP-7 and MMP-9 positive cells, suggesting a paracrine mechanism responsible for accelerated neointima formation.In conclusion, the results of our study do not support the use of skeletal myoblast for the treatment of vein graft disease after coronary artery bypass surgery. 相似文献
88.
J?rn L?tsch Carmen Walter Lisa Felden Christine Preibisch Ulrike N?th Till Martin Sandra Anti Ralf Deichmann Bruno G. Oertel 《Social cognitive and affective neuroscience》2012,7(6):698-707
Comparing pain is done in daily life and involves short-term memorizing and attention focusing. This event-related functional magnetic resonance imaging study investigated the short-term brain activations associated with the comparison of pain stimuli using a delayed discrimination paradigm. Fourteen healthy young volunteers compared two successive pain stimuli administered at a 10 s interval to the same location at the nasal mucosa. Fourteen age- and sex-matched subjects received similar pain stimuli without performing the comparison task. With the comparison task, the activations associated with the second pain stimulus were significantly greater than with the first stimulus in the anterior insular cortex and the primary somatosensory area. This was observed on the background of a generally increased stimulus-associated brain activation in the presence of the comparison task that included regions of the pain matrix (insular cortex, primary and secondary somatosensory area, midcingulate cortex, supplemental motor area) and regions associated with attention, decision making, working memory and body recognition (frontal and temporal gyri, inferior parietal lobule, precuneus, lingual cortices). This data provides a cerebral correlate for the role of pain as a biological alerting system that gains the subject''s attention and then dominates most other perceptions and activities involving pain-specific and non-pain-specific brain regions. 相似文献
89.
Recently, Laubender and Bender (Stat. Med. 2010; 29: 851–859) applied the average risk difference (RD) approach to estimate adjusted RD and corresponding number needed to treat measures in the Cox proportional hazards model. We calculated standard errors and confidence intervals by using bootstrap techniques. In this paper, we develop asymptotic variance estimates of the adjusted RD measures and corresponding asymptotic confidence intervals within the counting process theory and evaluated them in a simulation study. We illustrate the use of the asymptotic confidence intervals by means of data of the Düsseldorf Obesity Mortality Study. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
90.