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81.
Chris Fussman David Todem Johannes Forster Hassan Arshad Radvan Urbanek Wilfried Karmaus 《The Journal of asthma》2007,44(2):99-105
The effect of cow's milk consumption on childhood asthma has been debated for several years. This study attempts to provide further insight into this association through the use of a longitudinal study design. Newborns from parents with atopic history were recruited from Germany, Austria, and England (n = 696). For five repeated ascertainments, information was collected on cow's milk exposure, incidence of doctor-diagnosed asthma, and confounders. Generalized estimation equations, incorporating different models (concurrent, delayed, combined, and reverse causation), were used to determine this association. No association between cow's milk consumption and childhood asthma was found for the concurrent effects model (OR = 0.81, 95% confidence interval [CI]: 0.55, 1.20). In the delayed effects model, the direction of the association varied with time of follow-up. Thus, we stratified by period, which resulted in a significant protective delayed effect at 36 months (OR = 0.18, 95% CI = 0.06, 0.49). However, reverse causation negated this finding since the presence of asthma in prior months led to a reduction in further exposure to cow's milk (OR = 0.40, 95% CI = 0.16, 0.99). Hence, cow's milk consumption does not protect against childhood asthma. The apparent protection of cow's milk against asthma may result from parents of asthmatic children avoiding cow's milk, rather than actual prophylaxis. 相似文献
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85.
Sybille Spicker Jörg B. Schulz Dirk Petersen Michael Fetter Thomas Klockgether Johannes Dichgans 《Journal of neurology》1995,242(8):517-521
Eye movements were studied in 13 patients with Friedreich's ataxia and correlated with MRI findings to investigate whether oculomotor abnormalities can be traced to cerebellar disturbances in this disease. One of the most prominent eye signs was fixation instability (square-wave jerks, SWJ.). Besides SWJ the patients showed various combinations of cerebellar, vestibular and brain-stem oculomotor signs. Our patients did not comprise a homogeneous group with regard to their oculomotor findings. There was no correlation between the severity of any of the so-called cerebellar oculomotor disturbances and the number of SWJ. We tried to correlate the extent of oculomotor disturbances with floccular atrophy and atrophy of the dorsal vermis on MRI in seven of the patients. None of the oculomotor features (including SWJ) correlated with flocculus or dorsal vermis size. Furthermore, floccular and vermal measurements on MRI were normal. Accordingly, we think it unlikely that the oculomotor disturbances, including SWJ, are attributable to cerebellar pathology per se. 相似文献
86.
Michael Schwarz Frank Block Rudolf Tpper Karl-Heinz Sontag Johannes Noth 《Annals of neurology》1992,32(3):358-364
Intrastriatal injection of quinolinic acid (QA) in rats provides an animal model that mimics some of the neuropathological and neurochemical alterations observed in the striatum of patients with Huntington's disease (HD). One of the very early neurophysiological signs in HD is a diminution of amplitude of early somatosensory evoked potentials (SEPs) recorded over the parietal cortex. The present study investigated whether the QA model exhibits similar neurophysiological abnormalities. Two weeks after unilateral intrastriatal injection of QA (240 nmol) or of the solvent, early SEPs were recorded with chronically implanted electrodes from the somatosensory cortex or from the ventrobasal nucleus of the thalamus of lightly pentobarbital-anesthetized rats, in response to single-shock electrical stimulation of the contralateral forepaw. Whereas intrastriatal injection of solvent did not influence SEPs, the striatal QA lesion significantly reduced the amplitude of early cortical SEPs by about 40% without affecting the latency. SEPs recorded from the ventrobasal nucleus were unchanged after QA lesion. Histological examination and glial fibrillary acid protein staining after intrastriatal injection of QA revealed no evidence for damage in the somatosensory system. It is concluded that (1) the QA animal model of HD mimics some of the SEP abnormalities of patients, and (2) a striatal lesion modulates somatosensory transmission to the cortex in rats. 相似文献
87.
Norbert Rilinger Johannes Görich Reinhard Scharrer-Pamler Jochen Vogel Reinhard Tomczak Elmar Merkle Roman Sokiranski Hans-Jürgen Brambs 《Cardiovascular and interventional radiology》1997,20(4):263-267
Purpose To evaluate the clinical results of percutaneous transluminal rotational atherectomy in the treatment of peripheral vascular
disease.
Methods Rotational atherectomy was performed in 39 patients aged 39–87 years (mean 66.6 years). A total of 71 lesions (43 stenoses
and 28 occlusions) were treated in 40 limbs. Additional balloon angioplasty was required in 54% of lesions. Fifteen patients
(37.5%) presented in Fontaine stage II, 10 patients (25%) in Fontaine stage III and 15 patients (37.5%) in Fontaine stage
IV. Rotational atherectomy at 750 rpm was carried out over a 0.014-inch guidewire with continuous aspiration into a vacuum,
bottle. Follow-up angiography and color flow Doppler examinations were performed in 22 patients (23 limbs) after a mean period
of 6 months (range 2–14 months)
Results There was one primary technical failure. In 36 of 40 lesions there was a good angiographic result with residual stenoses in
less than 30%. In 70 lesions treated by rotational atherectomy, however, 54% showed residual stenoses of 30%–50% and these
cases required additional balloon angioplasty. The mean ankle-brachial index improved significantly (p<0.001), from 0.49 before the procedure to 1.01 after the procedure. A single distal embolus, related to primary recanalization,
occurred and there were two large inguinal hematomas. Cumulative clinical patency after 6 months was 83.8% and cumulative
angiographic patency after 6 months was 79.1%.
Conclusion Percutaneous rotational atherectomy is a promising approach for the treatment of chronic peripheral vascular disease. Further
prospective, randomized studies are necessary to compare percutaneous transluminal angioplasty with this new technical approach. 相似文献
88.
RO 15-1788, a specific benzodiazepine antagonist, although it effectively antagonizes the clinical effects of benzodiazepines (i.e., sedation and amnesia), can also induce subjective agonist effects such as sedation or inverse agonist effects such as anxiety. The purpose of this study was to investigate in seven healthy volunteers the effect of RO 15-1788 on cerebral blood flow when intravenously injected alone or with midazolam and to compare its effects with midazolam administered alone. Cerebral blood flow was measured with the 133xenon inhalation technique and the drugs were administered simultaneously in a double-blind, randomized fashion during the four following sessions: placebo-placebo; midazolam-placebo; RO 15-1788-placebo; midazolam-RO 15-1788. No difference in cerebral blood flow was noted between the placebo-placebo, the RO 15-1788-placebo, and the RO 15-1788-midazolam sessions--although midazolam injected alone decreased cerebral blood flow by 30%. The sedation, amnesia, and the electroencephalograph (EEG) and muscle tone changes observed with midazolam-placebo were not present during the RO 15-1788-placebo and RO 15-1788-midazolam sessions. This study demonstrates the absence of effects of RO 15-1788 on cerebral blood flow when injected alone and the efficacy of this new drug in antagonizing the depressant effects of midazolam on cerebral hemodynamics. 相似文献
89.
The echocardiographic data on 14 junior and 15 senior players in a first-division basketball club were compared. No difference was found between the senior and junior players as regards the thickness of the interventricular septum (11.47 vs 11.21 mm) or the thickness of the posterior wall of the left ventricle (9.8 vs 9.86 mm). The adults displayed a larger left ventricular end-diastolic diameter (56.8 vs 53.6 mm, P less than 0.05), end-diastolic volume (194 vs 164 ml, P less than 0.05), stroke volume (142 vs 116 ml, P less than 0.05), right ventricular diameter (27.9 vs 23.2, P less than 0.01), aortic root diameter (35.0 vs 32.0, P less than 0.05), and left atrial diameter (42.7 vs 37.2, P less than 0.01). However, among these, only the stroke volume and right ventricular diameter remained significantly different after normalization to body surface area. A significant difference could not be demonstrated in the linear ejection fraction, the ejection fraction, or the fractionated interventricular septum and posterior wall thicknesses. The examinations indicated that left ventricular hypertrophy had fully developed by the age of 18 years in the basketball players and that there was no further enhancement in adults. However, the left ventricular, right ventricular, and left atrial volume were larger in the adults than in the junior players. 相似文献
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