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1.
The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed. 相似文献
2.
Marie Warrer Petersen Tine Sylvest Meyhoff Marie Helleberg Maj-Brit Nørregaard Kjær Anders Granholm Carl Johan Steensen Hjortsø Thomas Steen Jensen Morten Hylander Møller Peter Buhl Hjortrup Mik Wetterslev Gitte Kingo Vesterlund Lene Russell Vibeke Lind Jørgensen Klaus Tjelle Thomas Benfield Charlotte Suppli Ulrik Anne Sofie Andreasen Thomas Mohr Morten H. Bestle Lone Musaeus Poulsen Mette Friberg Hitz Thomas Hildebrandt Lene Surland Knudsen Anders Møller Christoffer Grant Sølling Anne Craveiro Brøchner Bodil Steen Rasmussen Henrik Nielsen Steffen Christensen Thomas Strøm Maria Cronhjort Rebecka Rubenson Wahlin Stephan Jakob Luca Cioccari Balasubramanian Venkatesh Naomi Hammond Vivekanand Jha Sheila Nainan Myatra Christian Gluud Theis Lange Anders Perner 《Acta anaesthesiologica Scandinavica》2020,64(9):1365-1375
Introduction
Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists.Methods
The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals.Discussion
The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.3.
4.
Patients with primary major depression (N = 372) were followed for 2 years to determine the prognostic importance of past manic or hypomanic episodes. While bipolar I and bipolar II patients were more likely to relapse and bipolar I patients were more likely to attempt suicide, these patients resembled nonbipolar depressed patients in likelihood of recovery and psychosocial impairment in various areas. Compared to nonbipolar patients, those with bipolar I depression were much more likely to develop mania, while bipolar II patients were more likely to develop hypomania. Cycling during the index episode predicted a relatively low likelihood of recovery for bipolar I patients but had no apparent prognostic significance for patients with bipolar II illness. 相似文献
5.
A Andreasen A M Drewes J E Assentoft N E Larsen H Nielsen I E Holm F A Geneser 《Journal of neuroscience methods》1991,37(2):151-160
A large series of rabbit hippocampal Neo-Timm stained sections were manually aligned, digitized, and by a modified median filtration noise reduced and reconstructed into a three-dimensional object. From the presented simulated grey tone cuts of this object, the reader may assemble a rabbit hippocampal model, that spatially illustrates its anatomy. 相似文献
6.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
7.
Abstract A previous study of the sensitivity and accuracy of a standardized radiographic technique for the disclosure of root cavities in a cadaver material indicated that it was not possible to perceive small artificial “resorption” cavities. Using the same material, the aim of the present study was to evaluate whether the use of subtraction radiography would improve the detection of root cavities. In an autopsy material of five mandibular blocks each containing two premolars, small, medium, and large cavities were drilled in the cervical, middle, and apical thirds of the proximal and oral root surfaces. Each jaw block was radiographed before (B) and after (A) cavity preparation with three different exposure times resulting in light, medium, and dark film densities. The radiographs were digitized. Digital subtraction was performed between the A- and B images of varying densities by a computer program developed for dental subtraction radiography. Conventional and reverse contrast modes of the subtraction image were assessed independently by four observers. The results showed small inter- and intraobserver differences in diagnostic accuracy for assessment of total number of root cavities. Original film density did not influence the diagnostic performance in the resulting subtraction image. Contrast mode in the subtraction image influenced diagnostic performance as the majority of observers did best with the reverse contrast mode (p<0.05). Some of the small root cavities were disclosed by the subtraction technique, but overall accuracy was not increased compared to conventional radiography. 相似文献
8.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
9.
Adult zebrafish can completely regenerate their caudal fin following amputation. This complex process is initiated by the formation of an epithelial wound cap over the amputation site by 12 h post amputation (hpa). Once the cap is formed, mesenchymal cells proliferate and migrate from sites distal to the wound plane and accumulate under the epithelial cap forming the blastemal structure within 48 hpa. Blastemal cells proliferate and differentiate, replacing the amputated tissues, which are populated with angiogenic vessels and innervating nerves during the regenerative outgrowth phase which is completed around 14 days post amputation (dpa). Regenerative outgrowth does not occur in TCDD-exposed zebrafish. To identify the molecular pathways that are perturbed by TCDD exposure, male zebrafish were ip injected with 50 ng/g TCDD or vehicle and caudal fins were amputated. Regenerating fin tissue was collected at 1, 3, and 5 dpa for mRNA abundance analysis. Microarray analysis and quantitative real time PCR revealed that wound healing and regeneration alone altered the expression of nearly 900 genes by at least two-fold between 1 and 5 dpa. TCDD altered the abundance of 370 genes at least two-fold. Among these, several known aryl hydrocarbon responsive genes were identified in addition to several genes involved in extracellular matrix composition and metabolism. The profile of misexpressed genes is suggestive of impaired cellular differentiation and extracellular matrix composition potentially regulated by Sox9b. 相似文献
10.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14