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71.
Bhavesh Papadi Carole Boudreaux J. Allan Tucker Blaine Mathison Henry Bishop Mark E. Eberhard 《The American journal of tropical medicine and hygiene》2013,88(6):1062-1064
The genus Halicephalobus consists of eight species of free-living nematodes. Only one species (H. gingivalis) has been reported to infect vertebrates. Human infection is extremely rare, and only four cases have been reported in the literature. These nematodes seem to exhibit neurotropism, but their life cycle, mode of infection, and risk factors are poorly understood. Neurohelminthiases are not commonly recognized in the United States and when they do occur, pose great diagnostic challenges because of lack of appropriate non-invasive screening and/or confirmatory tests. We report a challenging case of meningoencephalomyelitis caused by a Halicephalobus sp., in which the patient had a rapidly deteriorating clinical course. The case did not raise any clinical suspicion of neurohelminthiases, although increased eosinophils were present in the cerebrospinal fluid. This case presents an opportunity to highlight the importance of considering parasitic infection in meningoencephalitis or meningoencephalomyelitis presenting atypically. 相似文献
72.
Mark L. Eberhard Gholamabbas Amin Ostovar Kote Chundu Dan Hobohm Iman Feiz-Erfan Blaine A. Mathison Henry S. Bishop Paul T. Cantey 《The American journal of tropical medicine and hygiene》2013,88(3):601-605
A 22-month-old girl presented with neck pain and stiffness and magnetic resonance imaging showed an extradural mass extending from C2 through the C4 level with moderate to severe compression of the cord. A left unilateral C2–C4 laminectomy was performed revealing an extradural rubbery tumor; a small biopsy was obtained. Examination of stained tissue revealed the presence of a parasitic worm that was identified as a gravid female Onchocerca lupi. A magnetic resonance imaging at 7 weeks follow-up showed a significantly decreased size of the enhancing lesion and the patient''s symptoms gradually resolved. This is the first report of zoonotic O. lupi in the United States. The parasite has been reported in dogs and cats in the western United States, and from people in four cases reported from Europe. A great deal more needs to be learned, including full host range and geographic distribution, before we fully understand O. lupi infections in animals and man. 相似文献
73.
von Eckardstein S Noe G Brache V Nieschlag E Croxatto H Alvarez F Moo-Young A Sivin I Kumar N Small M Sundaram K;International Committee for Contraception Research The Population Council 《The Journal of clinical endocrinology and metabolism》2003,88(11):5232-5239
Several preparations of testosterone and its esters are being investigated alone or in combination with other gonadotropin-suppressing agents as possible antifertility agents for men. We studied the effectiveness of 7 alpha-methyl-19-nortestosterone (MENT) as an antispermatogenic agent in men. MENT has been shown to be more potent than testosterone and to be resistant to 5 alpha-reduction. For sustained delivery of MENT, we used a system consisting of ethylene vinyl acetate implants containing MENT acetate (Ac), administered subdermally. Thirty-five normal volunteers were recruited in 3 clinics and were randomly assigned to 1 of 3 doses: 1 (12 men), 2 (11 men), or 4 (12 men) MENT Ac implants. The initial average in vitro release rate of MENT Ac from each implant was approximately 400 micro g/day. Implants were inserted subdermally in the medial aspect of the upper arm under local anesthesia. The duration of treatment was initially designed to be 6 months. However, in 2 clinics the duration of treatment was extended to 9 months for the 2-implant group and to 12 months for the 4-implant group. Dose-related increases in serum MENT levels and decreases in testosterone, LH, and FSH levels were observed. Effects on sperm counts were also dose related. None of the subjects in the 1-implant group exhibited oligozoospermia (sperm count, <3 million/ml). Four subjects in the 2-implant group became oligozoospermic, 2 of whom reached azoospermia. Eight subjects in the 4-implant group reached azoospermia, with 1 exhibiting oligozoospermia, whereas 2 were nonresponders. Side effects generally seen with androgen administration, such as increases in erythrocyte count, hematocrit, and hemoglobin and a decrease in SHBG, were also seen in this study and were reversible. Changes in lipid parameters were moderate and transient. Liver enzymes showed small changes. This study demonstrates that MENT Ac, when administered in a sustained release fashion via subdermal implants, can inhibit spermatogenesis over a prolonged period after a single administration and has the potential to be used as a male contraceptive. 相似文献
74.
Eberhard Gläss 《Journal of cancer research and clinical oncology》1960,63(3):294-310
Zusammenfassung Erwachsene Ratten wurden mit 4-Dimethylaminoazobenzol (“Buttergelb”) gefüttert und die Mitosen der Leberkerne nach Aufnahme
verschiedener Buttergelbmengen (200–1020 mg) auf Chromosomenzahlen und Mitoseanomalien hin untersucht. Um mehr Teilungsstadien
zu erhalten, wurde die Leber 48 Std vor der Fixierung partiell hepatektomiert. Auch in buttergelbbehandelten Rattenlebern
ist ein Mitosemuster vorhanden, dessen Zusammensetzung sich w?hrend der Buttergelbbehandlung in charakteristischer Weise ver?ndert:
Mit steigender Buttergelbdosis nehmen die diploiden Mitosen stark ab (von 44% auf 10%), die aneuploiden Stadien stark zu (von
13% auf 60%). Die Ver?nderungen vom euploiden (diploiden) zum aneuploiden Mitosemuster gehen sprunghaft vor sich, wobei die
erste Reaktionsschwelle nach 300 mg Buttergelbaufnahme liegt. Bei 939 untersuchten aneuploiden Metaphasen finden sich Chromosomenzahlen
zwischen 6 und 192. Von den in diesem Bereich enthaltenen 178 m?glichen aneuploiden Zahlen sind nur 50 realisiert. Die Zahlen
27, 33, 36, 48, 54, 69, 75, 96 sind dabei besonders h?ufig (78,5% aller aneuploiden Metaphasen). Mit steigender Buttergelbdosis
kommen zus?tzlich zu den bereits bevorzugt auftretenden vier aneuploiden Zahlen der unbehandelten Leber weitere aneuploide
Zahlen als bevorzugt hinzu, deren H?ufigkeit mit steigender Dosis ansteigt. Ferner treten neue aneuploide, nicht bevorzugte
Chromosomenzahlen auf. Sowohl für die neuauftretenden, bevorzugten wie nicht bevorzugten Klassen ist eine an bestimmte Buttergelbdosen
gebundene Entstehung charakteristisch.
Mit 4 Textabbildungen 相似文献
75.
Eberhard K. Walther M.D. 《Dysphagia》1995,10(4):275-278
Eighty-one patients were examined after laryngopharyngeal cancer surgery with a sequential computer manometry system using 4-channel-pressure probes. The general swallowing coordination is neither a matter of the oropharyngeal pressure thrust nor of the pharyngeal transit time, but mainly depends on swallowing initiation. The points of interest are both the pharyngeal inlet and outlet. The topographic correlates are the base of the tongue and the upper esophageal sphincter (UES). Resections of the base of the tongue lead to a decrease of volume available for pressure generation, thus reducing the tongue driving force. The swallowing reflex is uncoordinated resulting in dyskinesia of the UES. Compensation may be achieved with a stronger oropharyngeal thrust and/or repeated swallows. Distal resections alter the pharyngoesophageal segment so that a functional obstruction results, combined with lower pressure amplitudes in the hypopharynx, reducing the pressure gradient necessary for bolus flow. This increasing resistance can be overcome by higher propulsive forces in the base of the tongue region. In case of additional lingual defects, deglutition is subject to decompensation, highlighting the major role of the tongue as a pressure generator for bolus passage. 相似文献
76.
Riedel M 《Vnitr?ní lékar?ství》2000,46(12):874-880
Pulmonary embolism is nearly always a complication of deep venous thrombosis. The evaluation of risk factors for venous thromboembolism not only aids diagnosis but also guides decisions about the intensity of prophylactic measures. As both the extent and chronicity of pulmonary vascular obstruction vary widely, pulmonary embolism can produce widely differing clinical pictures. From the clinical, pathophysiological and therapeutical point of view, it is convenient to classify pulmonary embolism into four types: acute minor embolism (dyspnoea with or without pleuritic pain or haemoptysis), acute massive embolism (hemodynamic instability), subacute massive embolism (mimicking heart failure or indolent pneumonia), and chronic thromboembolic pulmonary hypertension (slowly progressing dyspnoea). This classification is of importance not only for the rational diagnosis and differential diagnosis, but also for the institution of adequate therapy. Because the disease has many nonspecific manifestations but no pathognomonic symptoms or signs, it is impossible to prove the diagnosis of pulmonary embolism alone on the basis of clinical presentation. 相似文献
77.
Karl Egerer Julia Hertzer Eugen Feist Anja Albrecht Paul Eberhard Rudolph Thomas Drner Gerd‐Rüdiger Burmester 《Arthritis care & research》2003,49(4):546-548
Objectives
To determine the usefulness of sE‐selectin as a marker for early diagnosis and stratification of rheumatoid arthritis.Methods
We investigated several markers of disease activity, including circulating adhesion molecules and other standard laboratory tests, in a 2–3 year followup analysis of patients with rheumatoid arthritis.Results
The mean ± SD levels of sE‐selectin (91.68 ± 31.8 ng/ml versus 49.83 ± 14.76 ng/ml) and rheumatoid factor (375.7 ± 394.4 U versus 44.66 ± 37.63 U) were strongly elevated in severe (n = 15) versus mild (n = 7) courses of disease. Statistical calculation of mean and standard deviation revealed that sE‐selectin represents a highly significant marker for the presence of persistent and aggressive disease over time, regardless of therapeutic intervention and observation time points (P = 0.0004). Notably, regression analysis identified constant values for all parameters analyzed and, therefore, a stable course of the disease could be predicted from the beginning.Conclusion
sE‐selectin appears to be a powerful marker to predict the severity of rheumatoid arthritis.78.
Eberhard P. Scholz Patrick Fischer Patrick Lugenbiel Panagiotis Xynogalos Patrick A. Schweizer Daniel Scherer Dierk Thomas Hugo A. Katus Edgar Zitron 《Journal of interventional cardiac electrophysiology》2018,53(3):347-355
Purpose
Left bundle branch block (LBBB) has a predictive value for response to cardiac resynchronization therapy as reported by Zareba et al. (Circulation 123(10):1061–1072, 2011). However, based on ECG criteria, the discrimination between complete LBBB and nonspecific intraventricular conduction delay is challenging. We tested the hypothesis that discrimination can be performed using standard electrophysiological catheters and a simple stimulation protocol.Methods
Fifty-nine patients were analyzed retrospectively. Patients were divided into groups of narrow QRS (n?=?20), wide QRS of right bundle branch block (RBBB) morphology (n?=?14), and wide QRS of LBBB morphology (n?=?25). Using a diagnostic catheter placed in the coronary sinus, left ventricular activation was assessed during intrinsic conduction as well as during right ventricular (RV) stimulation.Results
In patients with narrow QRS and RBBB, the Q-LV/QRS ratio was 0.43?±?0.013 (n?=?20) and 0.41?±?0.026 (n?=?14), respectively. In patients with LBBB morphology, the Q-LV/QRS split up into a group of patients with normal (0.43?±?0.022, n?=?7) and a group with delayed left ventricular activation (0.75?±?0.016, n?=?18). By direct comparison of the Q-LV/QRS ratio during intrinsic conduction with the Q-LV/QRS ratio during RV pacing leading to a functional LBBB, a clear distinction between a group of “true LBBB” and another group of “apparent LBBB”/nonspecific intraventricular conduction delay (NICD) could be generated.Conclusions
We present a novel and practical method that might facilitate discrimination between patients with apparent LBBB and true LBBB by comparing Q-LV/QRS ratios during intrinsic activation and during RV stimulation. Although this method can already be directly applied, validation by 3D electrical mapping and prospective correlation to cardiac resynchronization therapy (CRT) response will be required for further translation into clinical practice.79.
Michael Marxen Mark J. Jacob Lydia Hellrung Philipp Riedel Michael N. Smolka 《Human brain mapping》2021,42(5):1257
Our senses are constantly monitoring the environment for emotionally salient stimuli that are potentially relevant for survival. Because of our limited cognitive resources, emotionally salient distractors prolong reaction times (RTs) as compared to neutral distractors. In addition, many studies have reported fMRI blood oxygen level‐dependent (BOLD) activation of both the amygdala and the anterior insula for similar valence contrasts. However, a direct correlation of trail‐by‐trial BOLD activity with RTs has not been shown, yet, which would be a crucial piece of evidence to relate the two observations. To investigate the role of the above two regions in the context of emotional distractor effects, we study here the correlation between BOLD activity and RTs for a simple attentional capture by emotional stimuli (ACES) choice reaction time task using a general linear subject‐level model with a parametric RT regressor. We found significant regression coefficients in the anterior insula, supplementary motor cortex, medial precentral regions, sensory‐motor areas and others, but not in the amygdala, despite activation of both insula and amygdala in the traditional valence contrast across trials (i.e., negative vs. neutral pictures). In addition, we found that subjects that exhibit a stronger RT distractor effect across trials also show a stronger BOLD valence contrast in the right anterior insula but not in the amygdala. Our results indicate that the current neuroimaging‐based evidence for the involvement of the amygdala in RT slowing is limited. We advocate that models of emotional capture should incorporate both the amygdala and the anterior insula as separate entities. 相似文献
80.
M. Eberhard A.L.N. Schönenberger R. Hinzpeter A. Euler J. Sokolska L. Weber N. Kuzo R. Manka A.M. Kasel F.C. Tanner H. Alkadhi 《Journal of Cardiovascular Computed Tomography》2021,15(2):161-166
PurposeTo determine the reliability of subjective and objective quantification of mitral annular calcification (MAC) in elderly patients with severe aortic stenosis, to define quantitative sex- and age-related reference values of MAC, and to correlate quantitative MAC with mitral valve disease.MethodsIn this retrospective, IRB-approved study, we included 559 patients (268 females, median age 81 years, inter-quartile range 77–85 years) with severe aortic stenosis undergoing CT. Four independent readers performed subjective MAC categorization as follows: no, mild, moderate, and severe MAC. Two independent readers performed quantitative evaluation of MAC using the Agatston score method (AgatstonMAC). Mitral valve disease was determined by echocardiography.ResultsSubjective MAC categorization showed high inter-reader agreement for no (k ?= ?0.88) and severe MAC (k ?= ?0.75), whereas agreement for moderate (k ?= ?0.59) and mild (k ?= ?0.45) MAC was moderate. Intra-reader agreement for subjective MAC categorization was substantial (k ?= ?0.69 and 0.62). Inter- and intra-reader agreement for AgatstonMAC were excellent (ICC ?= ?0.998 and 0.999, respectively), with minor inconsistencies in MAC involving the left ventricular outflow tract/aortic valve. There were significantly more women than men with MAC (n ?= ?227, 85% versus n ?= ?209, 72%; p ?< ?0.001), with a significantly higher AgatstonMAC (median 597, range 81–2055 versus median 244; range 0–1565; p ?< ?0.001), particularly in patients ≥85 years of age. AgatstonMAC showed an area-under-the-curve of 0.84 to diagnose mitral stenosis, whereas there was no association of AgatstonMAC with mitral regurgitation (p ?> ?0.05).ConclusionsOur study in elderly patients with severe aortic stenosis shows that quantitative MAC scoring is more reliable than subjective MAC assessment. Women show higher AgatstonMAC scores than men, particularly in the elderly population. AgatstonMAC shows high accuracy to diagnose mitral stenosis. 相似文献