Search results for "REF"
showing 10 items of 8690 documents
Central correlation of muscle sympathetic nerve activation during baroreflex unloading - a microneurography-positron emission tomography study
2013
The baroreceptor reflex controls spontaneous fluctuations in blood pressure. One major control variable of the baroreflex is the sympathetic vasoconstrictor activity to muscles [MSNA; burst frequency (BF) and burst incidence (BI)], which can be quantitatively assessed by microneurography. We aimed to investigate the central regions involved in baroreflex regulation of MSNA. Healthy men (mean age 25 years) participated in three experimental sessions. (i) Microneurography recordings of MSNA from the left peroneal nerve during rest and baroreflex unloading, induced by lower body negative pressure (LBNP; -40 mmHg). If MSNA could be reliably recorded throughout this procedure (n = 15), the subje…
Interchangeability among five devices that measure anterior eye distances.
2014
The aim was to study the interchangeability of various devices that measure anterior chamber depth (ACD) and white-to-white (WTW) distance.Eighty right eyes of eighty patients aged 20 to 40 years were included. Their spherical equivalent ranged from -4.25 to +1.00 dioptres. Each eye's ACD and the WTW distance were measured using the following devices: a Castroviejo surgical calliper, CA-200F Corneal Analyser, Orbscan II, Pentacam HR and IOLMaster 500.The Pentacam HR measured significantly greater ACD (p0.01) than the other two devices, whereas IOLMaster 500 and Orbscan II yielded comparable (p0.01) distances. Nonetheless, in every device comparison, the mean difference was within clinically…
Altered functional connectivity between emotional and cognitive resting state networks in euthymic bipolar I disorder patients.
2013
Bipolar disorder is characterized by a functional imbalance between hyperactive ventral/limbic areas and hypoactive dorsal/cognitive brain regions potentially contributing to affective and cognitive symptoms. Resting-state studies in bipolar disorder have identified abnormal functional connectivity between these brain regions. However, most of these studies used a seed-based approach, thus restricting the number of regions that were analyzed. Using data-driven approaches, researchers identified resting state networks whose spatial maps overlap with frontolimbic areas such as the default mode network, the frontoparietal networks, the salient network, and the meso/paralimbic network. These ne…
The Influence of Music on Prefrontal Cortex during Episodic Encoding and Retrieval of Verbal Information: A Multichannel fNIRS Study.
2015
Music can be thought of as a complex stimulus able to enrich the encoding of an event thus boosting its subsequent retrieval. However, several findings suggest that music can also interfere with memory performance. A better understanding of the behavioral and neural processes involved can substantially improve knowledge and shed new light on the most efficient music-based interventions. Based on fNIRS studies on music, episodic encoding, and the dorsolateral prefrontal cortex (PFC), this work aims to extend previous findings by monitoring the entire lateral PFC during both encoding and retrieval of verbal material. Nineteen participants were asked to encode lists of words presented with eit…
Topodiagnostic value of blink reflex R1 changes: a digital postprocessing MRI correlation study.
2001
The aim of the study was to investigate the relation of the blink reflex R1 arc to known anatomical brainstem structures. Acute vascular brainstem lesions as identified by magnetic resonance imaging (MRI) of patients with isolated R1 pathology were superimposed into a stereotactic anatomical atlas using a new method of digital postprocessing. Isolated acute brainstem lesions were documented by diffusion-weighted MRI in 12 of 24 patients with unilateral R1 pathology. The lesions were located in the ipsilateral mid- to lower pons. In three patients only, the lesion had partial contact with the principal sensory nucleus of the trigeminal nerve (PSN) on at least one level. In two patients, the …
Differential impact of continuous theta-burst stimulation over left and right DLPFC on planning
2011
Most neuroimaging studies on planning report bilateral activations of the dorsolateral prefron- tal cortex (dlPFC). Recently, these concurrent activations of left and right dlPFC have been shown to dou- ble dissociate with different cognitive demands imposed by the planning task: Higher demands on the extraction of task-relevant information led to stronger activation in left dlPFC, whereas higher demands on the integration of interdependent information into a coherent action sequence entailed stronger activa- tion of right dlPFC. Here, we used continuous theta-burst stimulation (cTBS) to investigate the supposed causal structure-function mapping underlying this double dissociation. Two grou…
Prevalence of antibodies to human papillomaviruses in the general population of the Czech Republic.
1998
Sera from 450 individuals between the age of 1 and 80 years, representing the general population of the Czech Republic, were tested for the presence of antibodies to human-papillomavirus(HPV)-derived antigens. The following antigens were used: (i) HPV1 virions; (ii) HPV16, -18 and -33-virus-like particles (VLP); (iii) peptides derived from L2 open reading frames (ORFs) of HPV16 and HPV6/11; (iv) peptides derived from HPV16 E2, E4 and E7 ORFs of HPV16. The prevalence of antibodies reactive with the capsid-derived antigens was age-dependent, while no clear age dependence was observed in the distribution of antibodies to peptides derived from HPV16 early proteins. In individual sera, high corr…
A phase II study of alemtuzumab, fludarabine, cyclophosphamide, and doxorubicin (Campath-FCD) in peripheral T-cell lymphomas
2010
The clinical course of peripheral T-cell lymphoma (PTCL) is usually aggressive and the prognosis unfavorable. Therefore, there is a need for improvement of treatment options. Patients with newly diagnosed (n = 27) or refractory/relapsed (n = 11) PTCL received a combination of alemtuzumab, fludarabine, cyclophosphamide, and doxorubicin. The overall response rate (ORR) was 61%, with a complete response rate of 39%. In newly diagnosed patients the ORR was 63%, the median overall survival 25.9 months, and progression-free survival 11.8 months. In relapsed/refractory patients the median OS was 6.1 months. The most frequent grade 3/4 toxicities were leukopenia (95% of patients) and thrombocytopen…
Vulnerability of the right ventricle to cathodal, anodal, and bipolar stimulation at double diastolic threshold strength
1984
The repetitive ventricular response (RVR) to three stimulation techniques (bipolar, cathodal and anodal) was investigated in 35 patients. 26 patients suffered from coronary heart disease and 9 patients from dilative cardiomyopathy. The stimulation study was performed at a ventricular driving rate of 120/min with one and two premature ventricular extrastimuli. We used rectangular impulses of 1.8 ms duration at duable diastolic threshold strength. RVR was scored as follows: 0: no RVR, 1: one nonstimulated RVR, 2: two nonstimulated RVR, 3: three nonstimulated RVR, 4: four to ten nonstimulated RVR, 5: more than ten nonstimulated RVR lasting less than 2 minutes, 6: sustained ventricular tachycar…
Reference interval determination for N-terminal-B-type natriuretic peptide (NT-proBNP): A study in blood donors
2005
We assessed reference values in a group of apparently healthy blood donors. A total of 1980 blood donors was recruited and tested for the presence of NT-proBNP using a newly developed electrochemiluminescence immunoassay (ECLIA) method. NT-proBNP clustered in all blood donors below the age of 50 years and an upper limit of normal (ULN) was found to be 84 pg/ml for males and 146 pg/ml for females. Mean NT-proBNP values increased with increasing age which was due to an increasing number of individuals exceeding the ULN. Age- and gender-appropriate NT-proBNP levels decreased with increasing hemoglobin levels. Hemoglobin but not creatinine levels influenced the NT-proBNP concentration in this c…