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排序方式: 共有1374条查询结果,搜索用时 31 毫秒
61.
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Bo Chang Tanja Grau Susann Dangel Ron Hurd Bernhard Jurklies E. Cumhur Sener Sten Andreasson Helene Dollfus Britta Baumann Sylvia Bolz Nikolai Artemyev Susanne Kohl John Heckenlively Bernd Wissinger 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(46):19581-19586
Retinal cone photoreceptors mediate fine visual acuity, daylight vision, and color vision. Congenital hereditary conditions in which there is a lack of cone function in humans cause achromatopsia, an autosomal recessive trait, characterized by low vision, photophobia, and lack of color discrimination. Herein we report the identification of mutations in the PDE6C gene encoding the catalytic subunit of the cone photoreceptor phosphodiesterase as a cause of autosomal recessive achromatopsia. Moreover, we show that the spontaneous mouse mutant cpfl1 that features a lack of cone function and rapid degeneration of the cone photoreceptors represents a homologous mouse model for PDE6C associated achromatopsia. 相似文献
63.
Kurt Nikolai von Kaulla 《Journal of molecular medicine (Berlin, Germany)》1943,22(10):205-208
Zusammenfassung Es wird über die künstliche Hypoprothrombinämie durch Cumarinderivate berichtet. 相似文献
64.
Pre‐clinical heterotopic intrathoracic heart xenotransplantation: a possibly useful clinical technique 下载免费PDF全文
Bruno Reichart Stefan Buchholz Fabian Werner Isabelle Lutzmann Michael Schmoeckel Andreas Bauer Michael Thormann Martin Langenmayer Nadja Herbach Heike Pohla Rudolf Herzog Christopher G. A. McGregor David Ayares Eckhard Wolf Nikolai Klymiuk Andrea Baehr Alexander Kind Christian Hagl Ute Ganswindt Claus Belka Paolo Brenner 《Xenotransplantation》2015,22(6):427-442
65.
Meera R. Chappidi Heather J. Chalfin Daniel J. Johnson Max Kates Nikolai A. Sopko Michael H. Johnson Jen-Jane Liu Steven M. Frank Trinity J. Bivalacqua 《Urologic oncology》2017,35(2):38.e17-38.e24
Background
Patients with bladder cancer undergoing radical cystectomy (RC) experience high rates of perioperative blood transfusions (PBTs) and morbidity. The aim of this study was to evaluate the effect of blood storage duration on the risk of adverse perioperative outcomes in this high-risk patient population.Materials and methods
In a retrospective review of RC patients from 2010 to 2014 who received PBTs, the average storage duration for all units transfused was used to classify patients as receiving older blood using 3 different definitions (≥21 days,≥28 days, and≥35 days). Multivariable Poisson regression models were used to determine the adjusted relative risk of perioperative infections and overall morbidity in those given older blood compared to fresher blood.Results
Of the 451 patients undergoing RC, 205 (45%) received nonirradiated PBTs. In multivariable modeling, increasing average blood storage duration, as a continuous variable, was associated with an increased risk of infections (risk ratio [RR] = 1.08 per day, 95% CI: 1.01–1.17) and overall morbidity (RR = 1.08 per day, 95% CI: 1.01–1.15). Furthermore, ≥28-day blood storage (vs.<28) was associated with increased infections (RR = 2.69, 95% CI: 1.18–6.14) and morbidity (RR = 2.54, 95% CI: 1.31–4.95), and ≥35-day blood storage (vs.<35) was also associated with increased infections (RR = 2.83, 95% CI: 1.42–5.66) and morbidity (RR = 3.35, 95% CI: 1.95–5.77).Conclusions
Although blood is stored up to 42 days, storage≥28 days may expose RC patients to increased perioperative infections and overall morbidity compared with storage<28 days. Prospective cohort studies are warranted in cystectomy and other high-risk surgical oncology patients to better determine the effect of blood storage duration. 相似文献66.
Hyun Jae Pi Nikolai Otmakhov Farida El Gaamouch David Lemelin Paul De Koninck John Lisman 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(32):14437-14442
CaMKII is an abundant synaptic protein strongly implicated in plasticity. Overexpression of autonomous (T286D) CaMKII in CA1 hippocampal cells enhances synaptic strength if T305/T306 sites are not phosphorylated, but decreases synaptic strength if they are phosphorylated. It has generally been thought that spine size and synaptic strength covary; however, the ability of CaMKII and its various phosphorylation states to control spine size has not been previously examined. Using a unique method that allows the effects of overexpressed protein to be monitored over time, we found that all autonomous forms of CaMKII increase spine size. Thus, for instance, the T286D/T305D/T306D form increases spine size but decreases synaptic strength. Further evidence for such dissociation is provided by experiments with the T286D form that has been made catalytically dead. This form fails to enhance synaptic strength but increases spine size, presumably by a structural process. Thus very different mechanisms govern how CaMKII affects spine structure and synaptic function. 相似文献
67.
Femorodistal occlusion can be treated with bypasses or even with endovascular methods nowadays. The TransAtlantic Inter-Society Consensus (TASC) paper recommends the endovascular option for short occlusions up to 5 cm. The primary patency rates for both options are moderate: 70–80%. Since August 2007, the Viabahn Endoprosthesis with Propaten bioactive surface has been in clinical use. In open surgery, the surface activation by means of Propaten can improve the patency rates of femorodistal bypasses up to 97% during the first year after implantation. We show that implantation of the Viabahn Endoprosthesis is feasible; however, because midterm and long-term results are lacking, the patients should be followed up closely. 相似文献
68.
Nikolai E. Lazarov Sebastian Reindl Florian Fischer Manfred Gratzl 《Respiratory physiology & neurobiology》2009,165(2-3):131-136
Carotid body (CB) chemoreceptors are the main sensors detecting systemic hypoxia. Studies in animals revealed that dopamine and histamine may serve as transmitters between the chemoreceptor cells and the afferent nerve. To gain insight whether histamine and dopamine could play a role in the human CB and thus be important for the understanding of breathing disorders, we have investigated the chemosensory traits in human CBs from nine subjects of different ages obtained at autopsy. Immunohistochemistry revealed expression of histidine decarboxylase, vesicular monoamine transporter 2, histamine receptors 1 and 3 in virtually all chemosensory cells within the glomeruli of different ages. By contrast, catecholaminergic traits (tyrosine hydroxylase and vesicular monoamine transporter 1) were only detected in a subset of CB chemosensory cells at each age group while dopamine D2 receptors were expressed in the great majority of them. Our data suggest that histamine along with catecholamines may serve as transmitters between chemoreceptor cells and the afferent nerve in humans as well. 相似文献
69.
70.
Sanford J. Silverman Allegra A. Petti Nikolai Slavov Lance Parsons Ryan Briehof Stephan Y. Thiberge Daniel Zenklusen Saumil J. Gandhi Daniel R. Larson Robert H. Singer David Botstein 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(15):6946-6951
Oscillations in patterns of expression of a large fraction of yeast genes are associated with the “metabolic cycle,” usually seen only in prestarved, continuous cultures of yeast. We used FISH of mRNA in individual cells to test the hypothesis that these oscillations happen in single cells drawn from unsynchronized cultures growing exponentially in chemostats. Gene-expression data from synchronized cultures were used to predict coincident appearance of mRNAs from pairs of genes in the unsynchronized cells. Quantitative analysis of the FISH results shows that individual unsynchronized cells growing slowly because of glucose limitation or phosphate limitation show the predicted oscillations. We conclude that the yeast metabolic cycle is an intrinsic property of yeast metabolism and does not depend on either synchronization or external limitation of growth by the carbon source. 相似文献