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11.
Neil O''Connor Beate Hermelin 《Journal of child psychology and psychiatry, and allied disciplines》1990,31(2):203-215
Three groups of subjects, an idiot-savant group, a group of mentally handicapped subjects matched for IQ, and normal artistically gifted children, were compared for their recognition and graphic reproduction abilities. It was found that, independent of input modality, level of intelligence determined recognition performance, while graphic ability independent of IQ was the determining factor in reproduction accuracy. 相似文献
12.
Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA)
causes a near immediate and total decrease of transepithelial electrical
resistance (TER), continuation of exposure for 3 to 4 days results in a
tachyphylactic response as TER begins to return to control levels. Recovery
of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control
level. A reciprocal change in the transepithelial flux of D-mannitol
indicates that the TER decrease is indicative of an increase in tight
junction permeability. Exposure of cell sheets to TPA for several days also
results in the appearance of multilayered polyp- like foci (PLFs) across
the otherwise one cell layer thick cell sheets. The pattern of penetration
of the electron dense dye, ruthenium red, from the apical surface, across
the tight junction and into the lateral intercellular space indicates that
the tight junctions of the cell sheet become uniformly leaky after acute
exposure to TPA. However, when exposure is continued for several days, only
the junctions of cells in the PLFs manifest leakiness. The decrease in TER
following acute TPA exposure correlates with the translocation of protein
kinase C-alpha (PKC alpha) into a membrane-associated compartment. With
exposure of several days, only a trace of PKC alpha is visible by Western
immunoblot, and this is in the membrane-associated compartment.
Immunofluorescent microscopy indicates that the trace of PKC alpha seen in
the Western immunoblots is ascribable distinctly to cells of the PLFs.
Monolayer areas between PLFs show no discernible immunofluorescent signal.
The data therefore indicate that tight junction barrier function may be
restored in certain areas by the down regulation of PKC alpha from the
membrane-associated compartment. Failure to down regulate may result in the
paracellular leakiness and abnormal cell architecture of the PLFs. Possible
implications of this model for in vivo epithelial tumor promotion are
discussed.
相似文献
13.
Molecular analysis of PKU in Ireland 总被引:1,自引:0,他引:1
CA O'Neill RC Eisensmith DT Croke ER Naughten SF Cahalane SLC Woo 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):43-44
Classical phenylketonuria (PKU: McKusick No. 261600) is caused by mutations occurring at the phenylalanine hydroxylase (PAH) locus on chromosome 12 and has a prevalence in Ireland of 1 in 4500. We examined 304 independent alleles from 350 patients for the presence of six mutations and have characterized VNTR alleles within the minisatellite region 3' to the PAH gene in patients carrying the most prevalent mutation. R408W was the most common mutation found, with a relative frequency of 42%. All other mutations had relative frequencies of <10%. VNTR analysis showed that the R408W mutation is associated with the VNTR-8 allele in the Irish population, indicating that R408W is associated with RFLP haplotype 1. This differs from that reported from eastern Europe where R408W is associated with RFLP haplotype 2/VNTR-3; an observation which has led several groups to propose a Balto-Slavic origin for this mutation. These results support the hypothesis of a second, independent founding event for the R408W mutation on an RFLP haplotype 1 VNTR-8 chromsome background in the Irish/Celtic population. 相似文献
14.
K P Sherman J Goodfellow S Tibrewal J O''Connor 《Journal of the Royal Society of Medicine》1985,78(11):916-919
Thirty-two patients who underwent bilateral bicompartmental Oxford Meniscal Knee arthroplasty have been followed up prospectively for a mean period of 51 months from the time of their first operation. Pain relief was obtained in all but one knee; walking ability was improved in more than two-thirds. Overall patient satisfaction with the results was good. Two knees failed. The results demonstrate that bilateral knee arthroplasty can be expected to give good functional results. 相似文献
15.
16.
The past decade has seen the development of an array of complex flexible fibreoptic instruments for gastrointestinal (GI) endoscopy, and an increasing use of these for diagnostic and therapeutic purposes. It has been recognised more recently that the use of contaminated endoscopic equipment can lead to serious and occasionally fatal infections. Infection with a wide variety of micro-organisms has been reported following oesophago-gastroduodenoscopy (OGD) and endoscopic retrograde cholangio-pancreatography (ERCP). 相似文献
17.
Katja Nelson DDS Detlef Hildebrand DMD DT Juergen Mehrhof MDT 《Journal of prosthodontics》2008,17(7):591-595
This article describes a method of fabricating a fixed retrievable implant‐retained prosthesis based on electroforming. This method combines the advantages of both the cement‐ and screw‐retained prostheses, including passive fit, ease of fabrication, and retrievability. The absence of visible occlusal screw‐canals adds to its increased esthetic appeal. 相似文献
18.
Effects of ICI 141,292 on exercise tachycardia and isoprenaline-induced beta-adrenoceptor responses in man. 总被引:2,自引:2,他引:0 下载免费PDF全文
T H Pringle P C O''Connor A J McNeill M B Finch J G Riddell R G Shanks 《British journal of clinical pharmacology》1986,21(3):249-258
The beta-adrenoceptor blocking properties and cardioselectivity of ICI 141, 292 were investigated in healthy male subjects. Seven subjects received in random order oral doses of ICI 141,292 20, 50, 100, 200 and 400 mg, atenolol 50 and 100 mg and placebo. ICI 14 292 had no effect on supine heart rate which was reduced by atenolol 100 mg. ICI 141,292 50, 100 and 200 mg had no effect on standing heart rate which was reduced by 400 mg at 2 h. Both doses of atenolol caused greater reductions. The maximum percent reduction of an exercise tachycardia after ICI 141,292 200 mg (23.9 +/- 3.7%) and 400 mg (24.3 +/- 5.2%) were similar to atenolol 50 mg (27.3 +/- 4.7%) but less than atenolol 100 mg (30.8 +/- 2.9%) (P less than 0.02). Six subjects received in random order single oral doses of ICI 141,292 100, 200 and 400 mg, atenolol 50 mg, propranolol 40 mg and placebo. Following each dose each subject received graded infusions of isoprenaline sulphate until heart rate increased by 40 beats min-1. Dose-response curves were constructed for the changes in heart rate, finger tremor, blood pressure and forearm blood flow produced by each infusion. At the 4 micrograms min-1 dose of isoprenaline, ICI 141,292 200 mg caused more attenuation than atenolol 50 mg but less than propranolol 40 mg in the changes of heart rate, diastolic blood pressure and finger tremor (P less than 0.02). ICI 141,292 400 mg caused more attenuation of the changes of all parameters than atenolol 50 mg but less attenuation of the changes in diastolic blood pressure and finger tremor than propranolol 40 mg (P less than 0.02). These results indicate that ICI 141,292 is a cardioselective beta-adrenoceptor antagonist with partial agonist activity. 相似文献
19.
The incidence of adenocarcinoma and dysplasia in Barrett''s esophagus 总被引:17,自引:0,他引:17
J. Barry O''Connor M.D. Gary W. Falk M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1999,94(8):2037-2042
OBJECTIVE: The reported incidence of adenocarcinoma in Barrett's esophagus is variable. The aim of this study was to determine the incidence of dysplasia and adenocarcinoma in a population of patients with Barrett's esophagus followed prospectively and to compare these findings with other series. METHODS: All patients enrolled in the Cleveland Clinic Foundation's Barrett's esophagus registry from 1979 to 1995 were followed. Barrett's esophagus was defined as intestinal metaplasia anywhere in the tubular esophagus. The incidence of dysplasia and adenocarcinoma in these patients was recorded systematically. RESULTS: A total of 136 patients (91 male, 45 female) were followed in an endoscopic surveillance program for a mean of 4.2 yr and a total of 570 patient-years of follow-up. Thirty patients (22%) had short segment Barrett's esophagus. Two adenocarcinomas developed during follow-up, yielding an incidence of one per 285 patient-years of follow-up. Low grade dysplasia developed in 24 patients, whereas high grade dysplasia developed in four patients. CONCLUSIONS: Our study suggests that the incidence of adenocarcinoma in Barrett's esophagus is lower than initially thought. However, large multicenter studies are required to clarify the epidemiological and clinical factors related to the development of dysplasia and adenocarcinoma in Barrett's esophagus. 相似文献
20.