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排序方式: 共有1793条查询结果,搜索用时 31 毫秒
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Carola Eriksson Margareta Larsson Agneta Skoog Svanberg Tanja Tydén 《Upsala journal of medical sciences》2013,118(2):122-129
Background Different reasons influence the current low birth-rate and the postponement of the birth of the first child throughout Europe. The aim of this study was to explore how highly educated women and men in Sweden reflect on fertility and postponed parenthood.Methods We interviewed women (n = 22) and men (n = 18) who had started their professional careers and still had no children. Data were analysed with qualitative content analysis.Results Fertility was perceived as an unconsidered capacity, sometimes unpredictable, and different for women and men, but nevertheless taken for granted. The participants were of the opinion that fertility could be restored by assisted reproductive technologies or replaced by alternatives to a biological child. Postponed parenthood was described as an adaptation to societal changes and current discourses about parenthood as well as a consequence of a contemporary lifestyle with many competing priorities.Conclusion Highly educated young women and men in contemporary Sweden have competing priorities when planning and setting goals for their lives, and having children is one of them. They describe fertility as an imperceptible and retrievable capacity and postponed parenthood as a rational adaptation to changes in society. These findings suggest that increased information about the limitations of human reproduction is needed, but also that societal support for younger parents is of utmost importance. 相似文献
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Carola G. Vinuesa Michelle A. Linterman Chris C. Goodnow Katrina L. Randall 《Immunological reviews》2010,237(1):72-89
Summary: Germinal centers (GCs) are specialized microenvironments formed after infection where activated B cells can mutate their B-cell receptors to undergo affinity maturation. A stringent process of selection allows high affinity, non-self-reactive B cells to become long-lived memory B cells and plasma cells. While the precise mechanism of selection is still poorly understood, the last decade has advanced our understanding of the role of T cells and follicular dendritic cells (FDCs) in GC B-cell formation and selection. T cells and non-T-cell-derived CD40 ligands on FDCs are essential for T-dependent (TD) and T-independent GC formation, respectively. TD-GC formation requires Bcl-6-expressing T cells capable of signaling through SAP, which promotes formation of stable T:B conjugates. By contrast, differentiation of B blasts along the extrafollicular pathway is less dependent on SAP. T-follicular helper (Tfh) cell-derived CD40L, interleukin-21, and interleukin-4 play important roles in GC B-cell proliferation, survival, and affinity maturation. A role for FDC-derived integrin signals has also emerged: GC B cells capable of forming an immune synapse with FDCs have a survival advantage. This emerges as a powerful mechanism to ensure death of B cells that bind self-reactive antigen, which would not normally be presented on FDCs. 相似文献
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Nul D Zambrano C Diaz A Ferrante D Varini S Soifer S Grancelli H Doval H;Grupo de Estudio de la Sobrevida en la Insuficiencia Cardiaca en Argentina 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2005,19(2):125-134
Grupo de Estudio de la Sobrevida en la Insuficiencia Cardiaca en Argentina (GESICA) studied whether a standardized protocol for the initiation and titration of the β-blocker carvedilol in a multicenter, open-label program would optimize β-blocker use in heart failure (HF) patients. The program included: (1) the carvedilol initiation and titration period, and (2) long-term follow-up at 6 and 12 months. Of 1299 patients in the registry, 504 were excluded due to current therapy; of the remaining 795 eligible patients, 293 were excluded due to contraindications. Of the included patients with follow-up data (n = 316), 93.3% tolerated carvedilol initiation and 47.7% of the patients reached the target dose of 50 mg/day for a mean dose of 39 mg/day. Rates were comparable in the elderly (n = 83), of which 53% achieved a target dose for a mean dose of 43.08 mg/day. This protocol improved therapy rates and achieved target doses quickly (average of 4 visits). Concomitant medications did not have to be adjusted and there were low withdrawal rates (10%) and hospital admissions (7.2%) for HF. Patients were able to maintain carvedilol therapy at 6 and 12 months. These results indicate that a standardized titration protocol, as used in GESICA, for the initiation and titration of β-blockers is well tolerated and may improve β-blocker use in carefully selected heart failure patients.The study authors are members of the GESICA Steering Committee and Subcommittees 相似文献
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Domenico G. Della Rocca MD Michele Magnocavallo MD Veronica N. Natale MPH Carola Gianni MD PhD Sanghamitra Mohanty MD Chintan Trivedi MD MPH Carlo Lavalle MD Giovanni B. Forleo MD PhD Nicola Tarantino MD Jorge Romero MD Xiadong Zhang MD Mohamed Bassiouny MD Amin Al-Ahmad MD David J. Burkhardt MD Joseph G. Gallinghouse MD Javier E. Sanchez MD Rodney P. Horton MD Luigi Di Biase MD PhD Andrea Natale MD 《Journal of cardiovascular electrophysiology》2021,32(9):2441-2450
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Kisucka J Chauhan AK Patten IS Yesilaltay A Neumann C Van Etten RA Krieger M Wagner DD 《Circulation research》2008,103(6):598-605
The peroxiredoxin (Prdx) family of antioxidant enzymes uses redox-active cysteines to reduce peroxides, lipid hydroperoxides, and peroxynitrites. Prdx1 is known to be important to protect red blood cells against reactive oxygen species and in tumor prevention. In this study, the role of Prdx1 in inflammation, thrombosis, and atherosclerosis was investigated. Using intravital microscopy, we showed that the number of leukocytes rolling per minute in unstimulated veins was increased by 2.5-fold in Prdx1(-/-) compared to Prdx1(+/+) mice. In Prdx1(-/-) mice, 50% of leukocytes rolled at a velocity <10 mum/sec compared with 10% in Prdx1(+/+) mice, suggesting that adhesion molecule density on the endothelium may have been increased by Prdx1 deficiency. Indeed, endothelial P-selectin, soluble P-selectin, and von Willebrand factor in plasma were increased in Prdx1(-/-) mice compared to Prdx1(+/+) mice, indicating elevated Weibel-Palade body release. In contrast to this excessive endothelial activation, Prdx1(-/-) platelets showed no sign of hyperreactivity, and their aggregation both in vitro and in vivo was normal. We also examined the role of Prdx1 in the apoE(-/-) murine spontaneous model of atherosclerosis. Prdx1(-/-)/apoE(-/-) mice fed normal chow developed larger, more macrophage-rich aortic sinus lesions than Prdx1(+/+)/apoE(-/-) mice, despite similar amounts and size distributions of cholesterol in their plasma lipoproteins. Thus, Prdx1 protects against excessive endothelial activation and atherosclerosis, and the Prdx1(-/-) mice could serve as an animal model susceptible to chronic inflammation. 相似文献
39.
Mesenchymal stem cells remain of host origin even a long time after allogeneic peripheral blood stem cell or bone marrow transplantation 总被引:6,自引:0,他引:6
Rieger K Marinets O Fietz T Körper S Sommer D Mücke C Reufi B Blau WI Thiel E Knauf WU 《Experimental hematology》2005,33(5):605-611
OBJECTIVE: Plasticity of hematopoietic stem cells (HSC) has gained major interest in stem cell research. In order to investigate whether HSC may differentiate into mesenchymal stem cells (MSC), we assessed chimerism in peripheral blood (PB), mononuclear cell fractions (MNC) of bone marrow, and MSC derived from bone marrow (BM) from 27 up to 4225 days after allogeneic transplantation. PATIENTS AND METHODS: We applied fluorescence in situ hybridization using X/Y gene probes in sex-mismatched and STR-PCR in sex-matched patients. MSC could have been generated in 27 of 55 bone marrow samples derived from 20 patients. Fifteen patients received peripheral blood stem cell transplants (PBSCT), including CD34-selected PBSCT in two. Five patients received bone marrow. RESULTS: While all patients had chimerism in PB and MNC of the BM, in all but one patient BM-derived MSC were of recipient origin. This single patient showed reproducibly MSC of donor origin in a frequency of 1% after having received a CD34-selected PBSCT. Looking at graft collections, MSCs were easily generated from BM specimens, while no MSC could be derived from PBSC samples. CONCLUSION: Even though HSC have been found to differentiate into a variety of nonhematological cell types, they usually do not differentiate into MSC after allogeneic transplantation. 相似文献
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Timm Harder Sebastian Maurer-Stroh Anne Pohlmann Elke Starick Detlef H?reth-B?ntgen Karin Albrecht Gunter Pannwitz Jens Teifke Vithiagaran Gunalan Raphael T.C. Lee Carola Sauter-Louis Timo Homeier Christoph Staubach Carola Wolf Günter Strebelow Dirk H?per Christian Grund Franz J. Conraths Thomas C. Mettenleiter Martin Beer 《Emerging infectious diseases》2015,21(5):860-863
Highly pathogenic avian influenza (H5N8) virus, like the recently described H5N8 strain from Korea, was detected in November 2014 in farmed turkeys and in a healthy common teal (Anas crecca) in northeastern Germany. Infected wild birds possibly introduced this virus. 相似文献