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排序方式: 共有9903条查询结果,搜索用时 15 毫秒
41.
Marius Schwabenland Henrike Salié Jovan Tanevski Saskia Killmer Marilyn Salvat Lago Alexandra Emilia Schlaak Lena Mayer Jakob Matschke Klaus Püschel Antonia Fitzek Benjamin Ondruschka Henrik E. Mei Tobias Boettler Christoph Neumann-Haefelin Maike Hofmann Angele Breithaupt Nafiye Genc Christine Stadelmann Bertram Bengsch 《Immunity》2021,54(7):1594-1610.e11
42.
Video-rate nonlinear microscopy of neuronal membrane dynamics with genetically encoded probes 总被引:4,自引:0,他引:4
Biological membranes decorated with suitable contrast agents give rise to nonlinear optical signals such as two-photon fluorescence and harmonic up-conversion when illuminated with ultra-short, high-intensity pulses of infrared laser light. Microscopic images based on these nonlinear contrasts were acquired at video or higher frame rates by scanning a focused illuminating spot rapidly across neural tissues. The scan engine relied on an acousto-optic deflector (AOD) to produce a fast horizontal raster and on corrective prisms to offset the AOD-induced dispersion of the ultra-short excitation light pulses in space and time. Two membrane-bound derivatives of the green fluorescent protein (GFP) were tested as nonlinear contrast agents. Synapto-pHluorin, a pH-sensitive GFP variant fused to a synaptic vesicle membrane protein, provided a time-resolved fluorescent read-out of neurotransmitter release at genetically specified synaptic terminals in the intact brain. Arrays of dually lipidated GFP molecules at the plasma membrane generated intense two-photon fluorescence but no detectable second-harmonic power. Comparison with second-harmonic generation by membranes stained with a synthetic styryl dye suggested that the genetically encoded chromophore arrangement lacked the orientational anisotropy and/or dipole density required for efficient coherent scattering of the incident optical field. 相似文献
43.
Vitamin D food fortification in European countries: the underused potential to prevent cancer deaths
Niedermaier Tobias Gredner Thomas Kuznia Sabine Schöttker Ben Mons Ute Lakerveld Jeroen Ahrens Wolfgang Brenner Hermann 《European journal of epidemiology》2022,37(4):309-320
European Journal of Epidemiology - Background: Meta-analyses of randomized controlled trials have shown that vitamin D supplementation reduces cancer mortality by 13%. Vitamin D fortification of... 相似文献
44.
Suraj Suresh Mohammad Siddiqui Mouhanna Abu Ghanimeh Jessica Jou Stephen Simmer Vivek Mendiratta Sarah Russell Mustafa Al-Shammari Abigail Chatfield Eva Alsheik Duyen Dang Jeffrey Genaw Tobias Zuchelli 《Obesity research & clinical practice》2021,15(2):172-176
BackgroundAlthough recent studies have shown an association between obesity and adverse coronavirus disease 2019 (COVID-19) patient outcomes, there is a paucity in large studies focusing on hospitalized patients. We aimed to analyze outcomes associated with obesity in a large cohort of hospitalized COVID-19 patients.MethodsWe performed a retrospective study at a tertiary care health system of adult patients with COVID-19 who were admitted between March 1 and April 30, 2020. Patients were stratified by body mass index (BMI) into obese (BMI ≥ 30 kg/m 2) and non-obese (BMI < 30 kg/m 2) cohorts. Primary outcomes were mortality, intensive care unit (ICU) admission, intubation, and 30-day readmission.ResultsA total of 1983 patients were included of whom 1031 (51.9%) had obesity and 952 (48.9%) did not have obesity. Patients with obesity were younger (P < 0.001), more likely to be female (P < 0.001) and African American (P < 0.001) compared to patients without obesity. Multivariable logistic models adjusting for differences in age, sex, race, medical comorbidities, and treatment modalities revealed no difference in 60-day mortality and 30-day readmission between obese and non-obese groups. In these models, patients with obesity had increased odds of ICU admission (adjusted OR, 1.37; 95% CI, 1.07?1.76; P = 0.012) and intubation (adjusted OR, 1.37; 95% CI, 1.04?1.80; P = 0.026).ConclusionsObesity in patients with COVID-19 is independently associated with increased risk for ICU admission and intubation. Recognizing that obesity impacts morbidity in this manner is crucial for appropriate management of COVID-19 patients. 相似文献
45.
Welmoed van Loon Heike Rssig Susen Burock Jrg Hofmann Julian Bernhard Elisabeth Linzbach Domenika Pettenkofer Christian Schnfeld Maximilian Gertler Joachim Seybold Tobias Kurth Frank P. Mockenhaupt 《Emerging infectious diseases》2021,27(7):1931
Within 5 weeks in 2021, B.1.1.7 became the dominant severe acute respiratory syndrome coronavirus 2 lineage at an outpatient testing site in Berlin, Germany. Compared with outpatients with wild-type virus infection, patients with B.1.1.7 had similar cycle threshold values, more frequent sore throat and travel history, and less frequent anosmia/ageusia. 相似文献
46.
Paolo Dell’Oglio Philippa Meershoek Tobias Maurer Esther M.K. Wit Pim J. van Leeuwen Henk G. van der Poel Fijs W.B. van Leeuwen Matthias N. van Oosterom 《European urology》2021,79(1):124-132
BackgroundThe DROP-IN gamma probe was introduced to overcome the restricted manoeuvrability of traditional laparoscopic gamma probes. Through enhanced manoeuvrability and surgical autonomy, the DROP-IN promotes the implementation of radioguided surgery in the robotic setting.ObjectiveTo confirm the utility and safety profile of the DROP-IN gamma probe and to perform a comparison with the traditional laparoscopic gamma probe and fluorescence guidance.Design, setting, and participantsTwenty-five prostate cancer patients were scheduled for a robot-assisted sentinel lymph node (SN) procedure, extended pelvic lymph node dissection, and prostatectomy at a single European centre.Surgical procedureAfter intraprostatic injection of indocyanine green (ICG)-99mTc-nanocolloid (n = 12) or 99mTc-nanocolloid + ICG (n = 13), SN locations were defined using preoperative imaging. Surgical excision of SNs was performed under image guidance using the DROP-IN gamma probe, the traditional laparoscopic gamma probe, and fluorescence imaging.MeasurementsIntraoperative SN detection was assessed for the different modalities and related to anatomical locations. Patient follow-up was included (a median of 18 mo).Results and limitationsOverall, 47 SNs were pursued in vivo by the DROP-IN gamma probe, of which 100% were identified. No adverse events related to its use were observed. In vivo fluorescence imaging identified 91% of these SNs. The laparoscopic gamma probe identified only 76% of these SNs, where the detection inaccuracies appeared to be related to specific anatomical regions.ConclusionsOwing to improved manoeuvrability, the DROP-IN probe yielded improved SN detection rates compared with the traditional gamma probe and fluorescence imaging. These findings underline that the DROP-IN technology provides a valuable tool for radioguided surgery in the robotic setting.Patient summaryRadioguided robot-assisted surgery with the novel DROP-IN gamma probe is feasible and safe. It enables more efficient intraoperative identification of sentinel lymph nodes than can be achieved with a traditional laparoscopic gamma probe. The use of the DROP-IN probe in combination with fluorescence imaging allows for a complementary optical confirmation of node localisations. 相似文献
47.
48.
Olubukola O. Nafiu Christian Mpody Marc P. Michalsky Joseph D. Tobias 《Surgery for obesity and related diseases》2021,17(7):1249-1255
BackgroundRacial disparities in postsurgical complications are often presumed to be due to a higher preoperative co-morbidity burden among patients of black race, although being relatively healthy is not a prerequisite for a complication-free postoperative course.ObjectivesTo examine the association of race with short-term postbariatric surgery complications in seemingly healthy patients.SettingsMetabolic and Bariatric Surgery Accreditation and Quality Improvement Program database (2015–2018).MethodsWe studied a relatively healthy (American Society of Anesthesiologists physical status 1 or 2), propensity score–matched cohort of adult non-Hispanic black and non-Hispanic white bariatric surgery patients. We compared the risk-adjusted incidences of postoperative complications, serious adverse events, and measures of postoperative resource utilization across racial groups.ResultsWe identified 44,090 matched pairs of relatively healthy black and white bariatric surgery patients. Patients of black race were 72% more likely than those of white race to develop 1 or more postoperative complications (.7% versus .4%, respectively; odds ratio [OR], 1.72; 95% confidence interval [CI], 1.32–2.24; P < .01). Measures of postbariatric resource utilization were significantly higher in patients of black race than those of white race, including unplanned reoperations (1.3% versus 1.0%, respectively; OR, 1.28; 95% CI, 1.07–1.52; P = .01), unplanned readmissions (4.5% versus 3.0%, respectively; OR, 1.53; 95% CI, 1.38–1.69; P < .01), unplanned interventions (1.6% versus 1.2%, respectively; OR, 1.36; 95% CI, 1.16–1.60; P < .01), and extended hospital lengths of stay (51.2% versus 42.7%, respectively; OR, 1.41; 95% CI, 1.36–1.46; P < .01).ConclusionEven among relatively healthy patients, race appears to be an important determinant of postbariatric surgery complications and resource utilization. Research and interventions aimed at narrowing the racial disparities in bariatric surgery outcomes may need to broaden the focus beyond the racial variation in the preoperative co-morbidity burden. 相似文献
49.
Tobias Veit Dieter Munker Jürgen Barton Katrin Milger Teresa Kauke Bruno Meiser Sebastian Michel Michael Zoller Hans Nitschko Oliver T. Keppler Jürgen Behr Nikolaus Kneidinger 《American journal of transplantation》2021,21(10):3449-3455
Letermovir is a new antiviral drug approved for the prophylaxis of CMV infection in allogeneic stem cell transplants. The aim of the study was to assess the therapeutic efficacy of letermovir in difficult to treat CMV infections in lung transplant recipients. All lung transplant recipients between March 2018 and August 2020, who have been treated with letermovir for ganciclovir-resistant or refractory CMV infection were included in the study and analysed retrospectively. In total, 28 patients were identified. CMV disease was present in 15 patients (53.6%). In 23 patients (82.1%), rapid response was noticed, and CMV-viral load could be significantly decreased (>1 log10) after a median of 17 [14–27] days and cleared subsequently in all of these patients. Five patients (17.9%) were classified as non-responder. Thereof, development of a mutation of the CMV UL56 terminase (UL-56-Gen: C325Y) conferring letermovir resistance could be observed in three patients (60%). Common side effects were mild and mostly of gastrointestinal nature. Mild adjustments of the immunosuppressive drugs were mandatory upon treatment initiation with letermovir. In addition to other interventions, letermovir was effective in difficult to treat CMV infections in lung transplant recipients. However, in patients with treatment failure mutation conferring letermovir, resistance should be taken into account. 相似文献
50.
Bela Szabo Tobias Auberle Klaus Starke 《Naunyn-Schmiedeberg's archives of pharmacology》1993,348(3):249-257
Summary Inhibition of uptake, in the central nervous system leads to a decrease of sympathetic outflow to many tissues; central a2-adrenoceptors are involved in this decrease. The aim of the present study was to compare the effects of the selective uptake, inhibitor (+)-oxaprotiline on the plasma kinetics of noradrenaline and adrenaline in anaesthetized and in conscious rabbits. [3H]Noradrenaline and [3H]adrenaline were infused iv. The arterial plasma concentrations of endogenous and radiolabelled noradrenaline and adrenaline were measured, and the clearance from and spillover into the plasma of noradrenaline and adrenaline were calculated.Results obtained in conscious and anaesthetized rabbits were similar. (+)-Oxaprotiline 0.2, 0.6 and 1.8 mg kg–1 iv. dose-dependently reduced the clearance of [3H]noradrenaline from the plasma. The clearance of [3H]adrenaline was reduced less. The spillover of endogenous noradrenaline was decreased by up to 35%. In contrast, the spillover of adrenaline tended to be enhanced. Prazosin 0.1 and 1 mg kg–1 was injected iv. in a second part of each experiment. It lowered the blood pressure and caused a marked increase in noradrenaline spillover but no increase or even a decrease in adrenaline spillover.The results are compatible with the following hypothesis. The sympathetic outflow from the central nervous system is subject to a twofold a-adrenoceptor-mediated modulation: -adrenoceptor-mediated inhibition and 1-adrenoceptor-mediated excitation. In the control of the sympathetic outflow to many extra-adrenal tissues, the 2-adrenergic inhibition prevails. Uptake1 inhibitors depress sympathetic outflow to such tissues by enhancing the 2-adrenergic inhibition. In the regulation of the sympathetic outflow to the adrenal medulla, in contrast, 2-adrenergic inhibition and 1-adrenergic excitation have a similar impact. Uptake, inhibitors, hence, cause little change in adrenaline release: the two opposing influences cancel out. Prazosin produces an increase in noradrenaline but not adrenaline release because the loss of the central 1 sympathoexcitation attenuates at best slightly the baroreflex to most extra-adrenal tissues but dampens markedly the baroreflex to the adrenal medulla.
Correspondence to B. Szabo at the above address 相似文献