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21.
Atopy is associated with diminished cell-mediated immunity and increased amounts of IgE, both of which may be caused by imbalances of T lymphocyte subsets. We compared the composition of highly purified peripheral-blood T cells of fifteen atopic asthmatics with ten non-atopic control subjects. Each subject was examined on five separate occasions. Indirect immunofluorescence using monoclonal antibodies was used to define T cell subsets. We examined the proportion of T cells with T3 (most T cells), T4 (helper/inducer), T8 (suppressor/cytotoxic), M1 (natural killer), and Ia (activated T cells) surface antigens. Blood was obtained at the same time of day to eliminate the effects of circadian rhythm. Subjects were taking no medications. We found no difference between the groups of the percentage of T cells with T4, T8, M1, and Ia antigens, nor the ratio of T4+ (helper) to T8+ (suppressor) cells. T3 percent was slightly (94.3 vs 92.5%) higher in the atopic group. We conclude that atopic asthma is not associated with imbalances of peripheral-blood T cell subsets. 相似文献
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R. PETER FLECK PENG-SHENG GHEN KER BOYGE STANLEY HENJUM EDMUND BRENNAN GREGORY K. FELD 《Pacing and clinical electrophysiology : PACE》1993,16(2):360-367
A 44-year old male with Wolff-Parkinson-White syndrome presented with atrial fibrillation. The patient was found at the electrophysioiogical study to have two accessory pathways, one concealed and the other conducting exclusively in the anterograde direction. After radiofrequency catheter ablation of the anterograde conducting pathway, orthodromic reciprocating tachycardia, which previously could not be induced despite an aggressive protocol, was easily induced. Ablation of the concealed pathway resulted in termination of the tachycardia and suppression of inducibility. We propose that interaction between the two accessory pathways resulted in an inability to induce reciprocating tachycardia. 相似文献
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Five methods of diagnosis have been compared prospectively in 43 patients referred for suspected reflux oesophagitis. A final diagnosis of reflux oesophagitis, as defined by the presence of at least two of the three features of typical symptoms, abnormal endoscopic findings, and abnormal findings on oesophageal biopsy, was made in 27 patients. Observer error in the interpretation of endoscopic and histological appearances was small. Measurement of resting pressure of the lower oesophageal sphincter (LES) failed to identify individual patients with reflux oesophagitis, although the mean pressure in 26 patients with oesophagitis (10 1 ± 5 2 mm Hg) was significantly lower than in 13 patients without oesophagitis (16.8 ± 10.2 mm Hg, P<0.005). Barium studies were unhelpful, as a hiatus hernia was present in only 14 and barium reflux in only 11 of the 27 patients with oesophagitis. Acid perfusion (Bernstein test) was positive at 15 minutes in 23 of the 27 oesophagitis patients, but was falsely positive in seven of the 14 patients without oesophagitis. By accepting only those responses to acid perfusion which were positive at or before seven minutes, the false positive responses were reduced to one out of the 14 patients. Typical symptoms and/or an early positive Bernstein response will correctly identify most patients with reflux oesophagitis, but the diagnosis should be confirmed by endoscopy and biopsy when important therapeutic decisions are pending. 相似文献
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MICHAEL C. GIUDICI GREGORY C. FLAKER JACK J. CURTIS 《Pacing and clinical electrophysiology : PACE》1991,14(3):399-403
We report a patient who suffered an intraoperative AMI from injury to the distal portion of a dominant left circumflex coronary artery in the atrioventricular groove. Depending upon coronary anatomy and location of accessory pathways, compromise of coronary circulation by nonintrinsic pathology can be a major cause of morbidity. 相似文献
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Electromyographic studies of the onset of action of tubocurarine or alcuronium were performed on eight occasions in five patients who had liver masses. There was a slow onset of action and an increased dose requirement in those with malignant disease. Normal responses were found in a patient with benign nodular hyperplasia and in another where the malignant tumour was successfully treated with chemotherapy. 相似文献
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