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1.
ZQ Yin MD SG Crewther PhD B Pirie BSc DP Crewther PhD 《Clinical & experimental ophthalmology》1997,25(4):107-109
Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class. 相似文献
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The characteristics of the arterial oxygen saturation (SaO2) signal during episodes of hypoxaemia (SaO2 less than or equal to 80% for greater than or equal to 4 s) associated with periodic and non-periodic apnoeic pauses were studied in 16 preterm infants with cyanotic episodes (patients). and 15 asymptomatic preterm infants (controls), matched on birthweight and gestational age. The patients showed a significantly higher percentage of apnoeic pauses followed by a hypoxaemic episode (25 vs. 6%, P less than 0.01), and a two-fold increase in the slope of the desaturation curve (8.4 vs. 4.3% per s, P less than 0.005) in periodic compared with non-periodic breathing. All other characteristic of oxygenation (baseline SaO2 before episodes of hypoxaemia, delay between onset of apnoeic pause and onset of desaturation, lowest SaO2 during episodes of hypoxaemia) were similar for periodic and non-periodic breathing patterns. Similar, but not significant, differences between isolated and periodic apnoeic pauses were also present in the controls. An analysis of episodes of bradycardia (less than or equal to 100 beats per minute (bpm] showed that out of 121 episodes in the patients 118 were accompanied by a fall in SaO2 to less than or equal to 80%, and in the remaining three SaO2 fell to 82%, 85% and 86%, respectively. Thus all episodes of bradycardia (less than or equal to 100 bpm) were associated with a fall in SaO2 detected by beat-to-beat pulse oximetry. Examination of hypoxaemic episodes and their relationship with bradycardia and with apnoeic pauses, periodic and non-periodic, may help the further understanding of the control of arterial oxygenation in preterm infants with cyanotic episodes. 相似文献
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D. P. Southall M.D. M.R.C.P. V. A. Stebbens B.Sc. Research Assistant R. Mirza B.Sc. Research Assistant M. H. Lang B.Sc. Research Assistant C. B. Croft M.B. Ch.B. F.R.C.S E. A. Shinebourne M.D. F.R.C.P 《Developmental medicine and child neurology》1987,29(6):734-742
Six of 12 children with Down syndrome (DS) tested by means of long-term tape-recordings of oxygen saturation, breathing movements and expired CO2 were found to have previously undetected and severe upper airway obstruction during sleep. In five cases the obstruction occurred in the pharynx and in the sixth it was due to bilateral choanal stenosis. When compared with age-matched controls, overnight tape-recordings showed episodes of abnormal arterial hypoxaemia and an abnormally elevated end-tidal CO2. Episodes of obstruction were most marked during sleep associated with a non-regular breathing pattern. Abnormal episodes of hypoxaemia were associated with continued breathing movements. Sometimes there was no airflow (complete obstruction); at other times airflow continued normally or was reduced in amplitude (partial obstruction). During episodes of partial or complete airway obstruction the inspiratory waveform showed a characteristic shape. These results show sleep-related upper airway obstruction to be an often undetected complication of DS and all necessary measures should be taken to overcome the obstruction when it reaches the stage of producing abnormal hypoxaemia. Choanal dilatation and tracheostomy were successful in treating two of the children. Tonsillectomy and adenoidectomy were successful for one child, but only of marginal benefit for two others. 相似文献
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A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency. 相似文献
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