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排序方式: 共有680条查询结果,搜索用时 15 毫秒
1.
2.
A comparison between fast and conventional spin-echo in the detection of multiple sclerosis lesions 总被引:2,自引:0,他引:2
J. W. Thorpe S. F. Halpin D. G. MacManus G. J. Barker B. E. Kendall D. H. Miller 《Neuroradiology》1994,36(5):388-392
Long repetition time (TR) spin-echo (SE) with T2- or proton density weighting is the sequence of choice to detect the brain lesions of multiple sclerosis (MS). Fast spin-echo (FSE) permits the generation of T2-weighted images with similar contrast to SE but in a fraction of the time. We compared the sensitivity of FSE and SE in the detection of the brain lesions of MS. Six patients with clinically definite MS underwent brain imaging with both dual echo (long TR, long and short echo time (TE) SE and dual echo FSE. The SE and FSE images were first reviewed independently and then compared. A total of 404 lesions was detected on SE and 398 on FSE. Slightly more periventricular lesions were detected using SE than FSE (145 vs 127), whereas more posterior cranial fossa lesions were detected by FSE (77 vs 57). With both SE and FSE the short TE images revealed more lesions than the long echo. These results suggest that FSE could replace SE as the long TR sequence of choice in the investigation of MS. 相似文献
3.
CA von Arnim R Spoelgen ID Peltan M Deng S Courchesne M Koker T Matsui H Kowa SF Lichtenthaler MC Irizarry BT Hyman 《The Journal of neuroscience》2006,26(39):9913-9922
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD. 相似文献
4.
应用放射配体结合法证实大鼠胸腺内存在降黑素特异结合部位,该结合位点可以满足特异结合部位的基本条件:1.低结合容量;2.高亲和力;3.可饱和性;4.可逆性;5.对降黑素高度特异性。此外,该特异结合位点具昼夜节律;亚细胞分布的研究表明以细胞核含量最高,线粒体次之,并具有年龄依赖性降低,以出生时最高。 相似文献
5.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
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8.
Diagnosing CADASIL using MRI: evidence from families with known mutations of Notch 3 gene 总被引:4,自引:1,他引:3
Clinical data and MRI findings are presented on 18 subjects from two families with neuropathologically confirmed CADASIL.
DNA analysis revealed mutations in exon 4 of Notch 3 gene in both families. All family members with mutations in Notch 3 gene
had extensive abnormalities on MRI, principally lesions in the white matter of the frontal lobes and in the external capsules.
Of several family members in whom a diagnosis of CADASIL was suspected on the basis of minor symptoms, one had MRI changes
consistent with CADASIL; none of these cases carried a mutation in the Notch 3 gene. MRI and clinical features that may alert
the radiologist to the diagnosis of CADASIL are reviewed. However, a wide differential diagnosis exists for the MRI appearances
of CADASIL, including multiple sclerosis and small-vessel disease secondary to hypertension. The definitive diagnosis cannot
be made on MRI alone and requires additional evidence, where available, from a positive family history and by screening DNA
for mutations of Notch 3 gene.
Received: 17 February 1999 Accepted: 23 July 1999 相似文献
9.
10.
Stephen J Halpin P John Hamlin Daniel P Gree Lisa Warren Alexander C Ford 《World journal of gastroenterology : WJG》2013,19(7):1091-1097
AIM:To suggest infliximab(IFX) is effective for acute severe ulcerative colitis,from real-life clinical practice.METHODS:All patients receiving IFX for the treatment of acute severe ulcerative colitis in a single centre were included.Data were extracted from clinical records in order to assess response to IFX therapy.The primary endpoint was colectomy-free survival,and secondary outcomes included glucocorticosteroid-free remission and safety,which was evaluated by recording deaths and adverse events.Demographic and clinical characteristics of those who underwent colectomy and those who were colectomy-free,both at discharge from their index admission,and during follow-up after an initial response to IFX were compared.RESULTS:Forty-four patients(16 females,mean age 36 years) received IFX between May 2006 and January 2012 for acute severe ulcerative colitis.The median duration of follow-up post-first infusion was 396 d(interquartile range = 173-828 d).There were 21(47.7%) patients with < 1 year of follow-up,10(22.7%) with 1 years to 2 years of follow-up,and 13(29.5%) with > 2 years of follow-up post-first infusion of IFX.Overall,35(79.5%) responded to IFX,avoiding colectomy during their index admission,29(65.9%) were colectomyfree at last point of follow-up(median follow-up 396 d),and 25(56.8%) were in glucocorticosteroid-free remission at end of follow-up.There was one death from post-operative sepsis,20 d after a single IFX infusion.Colectomy rates were generally lower among those "bridging" to thiopurine.Of 18 patients "bridged" to thiopurine therapy,17(94.4%) were colectomyfree,and 15(83.3%) were in glucocorticosteroid-free remission at study end.No predictors of response were identified.CONCLUSION:IFX is effective for acute severe ulcerative colitis in real-life clinical practice.Two-thirds of patients avoided colectomy,and more than 50% were in glucocorticosteroid-free remission. 相似文献