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排序方式: 共有1457条查询结果,搜索用时 15 毫秒
91.
92.
Farah Perveen Mughal Ann Christina Bergmann Ha Uyen Buu Huynh Sarah Hyllekvist Jrgensen Inaam Mansha Meliha Kesmez Patrick Mark Schürch Alexandre Pierre Andr Theocharides Paul Robert Hansen Tina Friis Morten Orebo Holmstrm Evaldas Ciplys Rimantas Slibinskas Peter Hjrup Gunnar Houen Nicole Hartwig Trier 《International journal of molecular sciences》2022,23(12)
Myeloproliferative Neoplasms (MPNs) constitute a group of rare blood cancers that are characterized by mutations in bone marrow stem cells leading to the overproduction of erythrocytes, leukocytes, and thrombocytes. Mutations in calreticulin (CRT) genes may initiate MPNs, causing a novel variable polybasic stretch terminating in a common C-terminal sequence in the frameshifted CRT (CRTfs) proteins. Peptide antibodies to the mutated C-terminal are important reagents for research in the molecular mechanisms of MPNs and for the development of new diagnostic assays and therapies. In this study, eight peptide antibodies targeting the C-terminal of CRTfs were produced and characterised by modified enzyme-linked immunosorbent assays using resin-bound peptides. The antibodies reacted to two epitopes: CREACLQGWTE for SSI-HYB 385-01, 385-02, 385-03, 385-04, 385-07, 385-08, and 385-09 and CLQGWT for SSI-HYB 385-06. For the majority of antibodies, the residues Cys1, Trp9, and Glu11 were essential for reactivity. SSI-HYB 385-06, with the highest affinity, recognised recombinant CRTfs produced in yeast and the MARIMO cell line expressing CRTfs when examined in Western immunoblotting. Moreover, SSI-HYB 385-06 occasionally reacted to CRTfs from MPN patients when analysed by flow cytometry. The characterized antibodies may be used to understand the role of CRTfs in the pathogenesis of MPNs and to design and develop new diagnostic assays and therapeutic targets. 相似文献
93.
94.
Lee Connie M. S. Fong Kenneth N. K. Mok Maggie M. Y. Lam M. K. Kung Y. Chan Paven P. W. Ma Maggie K. M. Lui S. L. Kwan Lorraine P. Y. Chu W. L. Hui P. C. Yau Christina S. F. Kwan Ivan W. L. Chan Kelsey Y. M. Chan T. M. 《Virtual Reality》2023,27(3):1571-1583
Virtual Reality - Cognitive impairment is not uncommon in patients with end-stage renal disease and can make it more difficult for these patients to carry out peritoneal dialysis (PD) on their own.... 相似文献
95.
Quality of life development during initial hemodialysis therapy and association with loss of residual renal function 下载免费PDF全文
Christina G. Poulsen Krista D. Kjaergaard Christian D. Peters Bente Jespersen Jens D. Jensen 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(3):409-421
Introduction: Health related quality of life (HRQOL) is markedly reduced in hemodialysis patients compared to the general population. We investigated the course of self‐reported HRQOL over time and the association with selected factors, focusing on changes in glomerular filtration rate (GFR). Methods: Eighty‐two newly started hemodialysis patients from the SAFIR cohort filled out the Kidney Disease Quality of Life Short Form Version 1.3 (KDQOL‐SFTM) questionnaire at baseline, 6 and 12 months. The SAFIR study was a randomized, placebo‐controlled, double‐blind intervention study, examining the effects of the angiotensin II receptor blocker irbesartan. HRQOL was a secondary outcome measure. Main inclusion criteria: Dialysis vintage <1 year, left ventricular ejection fraction >30% and urinary output >300 mL/day. GFR was measured with mean creatinine and urea clearance from 24‐hour urine collections at baseline, 6 and 12 months. Findings: Irbesartan treatment did not affect HRQOL. Patients were pooled into one group for further analyses. Decline in GFR correlated significantly with decreasing HRQOL over time. HRQOL was stable over time, with a slight nonsignificant tendency toward improved HRQOL. The largest HRQOL‐differences (positive values equal improved HRQOL) observed during the 12 month study period were (mean[95% confidence interval]): Burden of kidney disease:6.4[?2.2;15.0], Role limitations‐physical:12.7[?2.1;27.5], and Role limitations‐emotional:9.7[?5.2;24.6]. Comorbidity, especially diabetes, hospital admissions, female gender, and age were strongly associated with lower HRQOL in cross sectional analysis. Discussion: Preservation of residual renal function seems to be important for HRQOL. In newly started HD patients, HRQOL showed little change after 12 months. HRQOL was negatively affected by comorbidity, especially diabetes, hospital admissions, female gender, and age. 相似文献
96.
Asmaa Elbakry Eva‐Christina Wurster Alaa Zaky Renate Liebl Edith Schindler Petra Bauer‐Kreisel Torsten Blunk Reinhard Rachel Achim Goepferich Miriam Breunig 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(24):3847-3856
Because nanoparticles are finding uses in myriad biomedical applications, including the delivery of nucleic acids, a detailed knowledge of their interaction with the biological system is of utmost importance. Here the size‐dependent uptake of gold nanoparticles (AuNPs) (20, 30, 50 and 80 nm), coated with a layer‐by‐layer approach with nucleic acid and poly(ethylene imine) (PEI), into a variety of mammalian cell lines is studied. In contrast to other studies, the optimal particle diameter for cellular uptake is determined but also the number of therapeutic cargo molecules per cell. It is found that 20 nm AuNPs, with diameters of about 32 nm after the coating process and about 88 nm including the protein corona after incubation in cell culture medium, yield the highest number of nanoparticles and therapeutic DNA molecules per cell. Interestingly, PEI, which is known for its toxicity, can be applied at significantly higher concentrations than its IC50 value, most likely because it is tightly bound to the AuNP surface and/or covered by a protein corona. These results are important for the future design of nanomaterials for the delivery of nucleic acids in two ways. They demonstrate that changes in the nanoparticle size can lead to significant differences in the number of therapeutic molecules delivered per cell, and they reveal that the toxicity of polyelectrolytes can be modulated by an appropriate binding to the nanoparticle surface. 相似文献
97.
Huixia Yang Zhi Ma Lin Peng Christina Kuhn Martina Rahmeh Sven Mahner Udo Jeschke Viktoria von Schnfeldt 《International journal of molecular sciences》2021,22(16)
Epigenetics play a vital role in early embryo development. Offspring conceived via assisted reproductive technologies (ARTs) have a three times higher risk of epigenetic diseases than naturally conceived children. However, investigations into ART-associated placental histone modifications or sex-stratified analyses of ART-associated histone modifications remain limited. In the current study, we carried out immunohistochemistry, chip-sequence analysis, and a series of in vitro experiments. Our results demonstrated that placentas from intra-cytoplasmic sperm injection (ICSI), but not in vitro fertilization (IVF), showed global tri-methylated-histone-H3-lysine-4 (H3K4me3) alteration compared to those from natural conception. However, for acetylated-histone-H3-lysine-9 (H3K9ac) and acetylated-histone-H3-lysine-27 (H3K27ac), no significant differences between groups could be found. Further, sex -stratified analysis found that, compared with the same-gender newborn cord blood mononuclear cell (CBMC) from natural conceptions, CBMC from ICSI-boys presented more genes with differentially enriched H3K4me3 (n = 198) than those from ICSI-girls (n = 79), IVF-girls (n = 5), and IVF-boys (n = 2). We also found that varying oxygen conditions, RNA polymerase II subunit A (Polr2A), and lysine demethylase 5A (KDM5A) regulated H3K4me3. These findings revealed a difference between IVF and ICSI and a difference between boys and girls in H3K4me3 modification, providing greater insight into ART-associated epigenetic alteration. 相似文献
98.
Christina Wildfire Engin Çiftyürek Katarzyna Sabolsky Edward M. Sabolsky 《Journal of Materials Science》2014,49(14):4735-4750
The incorporation of selective nanomaterials, such as common metal oxide semiconductor compositions, into resistive-type gas sensors has been shown by many researchers to lead to very high sensitivities and response rates, especially for micro-sized chemical sensors for room-temperature applications. The same strategy utilizing sensing nanomaterials has not been demonstrated for high-temperature sensors due to the intrinsic instability of typical metal oxide semiconductor nanomaterials at temperatures >500 °C. Within this work, doped Gd2Zr2O7 (GZO) nanomaterial compositions were investigated for H2 resistive-type sensors for applications between 600 and 1000 °C. This paper investigates the mechanism of H2 sensing for doped GZO nanomaterials and SnO2/GZO nanocomposites at the elevated temperatures. By integrating 10 vol.% nano-SnO2 into yttrium-doped GZO nanomaterials, a sensitivity of 4.15 % was retained for 4000 ppm H2 levels with a low signal drift of 0.42 %/h at 1000 °C in a 20 % O2/N2 gas stream. The signal drift was reduced by more than half of that compared to pure nano-SnO2 at the same conditions. The nano-GZO limited the grain growth of the nano-SnO2 particles and also prevented the nano-SnO2 from fully reducing to Sn at high temperatures in a low oxygen atmosphere. It is among the first resistive-type sensors operating at 1000 °C with sensing times of <5 min. This demonstration provided an example of a strategy of combining traditional metal oxide semiconductor and refractory nanomaterial compositions to form sensing nanocomposites with new sensing mechanisms, as well as, enhanced chemical and microstructural stabilities in high-temperature environments. 相似文献
99.
The purpose of the study was to determine the level of energy expenditure and exposure to air pollution for bicycle messengers. Relationships between heart rate (HR) and oxygen uptake, and between HR and pulmonary ventilation (VE) for each participant were established in laboratory tests. Air pollution and HR were measured during one working day. The total oxygen uptake was then described as the total energy expenditure in Joule (J) and in multiples of the energy expenditure at rest (MET). The mean energy expenditure during a working day (8 h) was 12 MJ, (4.8 MET). The level of air pollution exposure when cycling seemed to be comparable with the levels of exposure when sitting inside a vehicle. The VE during cycling was four times higher than resting value. Increased VE led to increased exposure to air pollution. 相似文献
100.
Sven A. Carlsson Stefan Henningsson Stefan Hrastinski Christina Keller 《Information Systems and E-Business Management》2011,9(1):109-131
Design science research is an essential part of IS research since the field should not only try to understand how the world
is, but also how to change it. We argue that the aim of IS design science research should be to develop practical knowledge
not only for the design of novel information technology (IT), but also for IS governance and management. Whereas at least
some methodological support exists for researchers engaged in IT-centric design science research, limited support is available
for researchers who want to develop design knowledge and theory for IS governance and management. To overcome this shortcoming,
we suggest a socio-technical IS design science research approach. The approach has four main activities: (1) identifying problem
situations and desired outcomes, (2) reviewing extant theories, knowledge and data, (3) proposing/refining design theory and
knowledge, and (4) testing design theory and knowledge. The applicability and usefulness of the proposed approach is shown
by means of a design science research project concerning IS integration management in the context of mergers and acquisitions. 相似文献