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排序方式: 共有463条查询结果,搜索用时 15 毫秒
101.
Quantification of blood flow with dynamic MR imaging and presaturation bolus tracking 总被引:1,自引:0,他引:1
A technique is described for rapid imaging of blood flow and dynamic measurement of its velocity. The method is a combination of bolus tracking and low-flip-angle gradient-echo cine angiography. This method provides precise determination of velocity with high temporal resolution in a single measurement. Unlike what occurs in phase imaging techniques, flow is displayed directly, eliminating potential errors that result from non-flow-related sources of phase shifts. Manipulation of raw data sets is avoided. Results obtained from a flow phantom, healthy volunteers, and a patient with an aortic aneurysm demonstrate the capability of the technique to track flow at low and high velocities and to differentiate flowing blood from thrombus. Because of its conceptual simplicity, rapidity, and lack of susceptibility to extraneous phase shifts, this technique may prove ideal for in vivo flow measurement and evaluation of flow patterns. 相似文献
102.
A 14-item Sexual Coercion Inventory (SCI) wasadministered to an urban university sample in WesternIndia. Twenty-six percent of the sample reported a totalof 160 incidents of sexual coercion ranging in severity from unwanted kissing to sexualintercourse. The most common outcome was intercourse andwas followed by kissing and fondling. No genderdifferences were discovered regarding victim status ortypes of coercion tactics experienced. A MANOVAanalysis found no overall gender effect, but maritalstatus and protected class membership did have asignificant effect with people who are married andprotected class members reporting more sexual coercion.Reasons for the lack of an overall gender effect andlimitations of this research are discussed. 相似文献
103.
104.
Close mapping of the focal non-epidermolytic palmoplantar keratoderma (PPK) locus associated with oesophageal cancer (TOC) 总被引:1,自引:1,他引:1
Kelsell DP; Risk JM; Leigh IM; Stevens HP; Ellis A; Hennies HC; Reis A; Weissenbach J; Bishop DT; Spurr NK; Field JK 《Human molecular genetics》1996,5(6):857-860
Focal non-epidermolytic palmoplantar keratoderma (PPK or palmoplantar
ectodermal dysplasia type III) is associated with oesophageal cancer in
three families: two large pedigrees located in Liverpool, UK and in the
midwestern American states and one smaller family from Germany. In these
families, the PPK is inherited as autosomal dominant and has a late onset,
usually manifesting between 7 and 8 years of age. The disease is
characterised by thickening of the pressure areas of the soles, but is not
restricted to the feet and also presents with oral leukokeratosis and
follicular hyperkeratosis. The disease locus [previously termed the
"tylosis oesophageal cancer gene' (TOC) locus] has been mapped to
17q23-qter by linkage analysis. This region is located telomeric to the
keratin 16 gene, in which mutations have been identified in focal PPK
families who show no increased cancer risk. We describe the close mapping
of this locus to the interval between AFMb054zf9 and D17S1603 using
haplotype analysis of additional Genethon markers in the region and show
that although the American family is unlikely to be related to either of
the other two, the UK and German pedigrees may share a common descent. This
work provides a basis for positional cloning and candidate gene analysis in
order to identify a gene that may be involved in familial oesophageal
cancer.
相似文献
105.
TIM-4 is the ligand for TIM-1, and the TIM-1-TIM-4 interaction regulates T cell proliferation 总被引:15,自引:0,他引:15
Meyers JH Chakravarti S Schlesinger D Illes Z Waldner H Umetsu SE Kenny J Zheng XX Umetsu DT DeKruyff RH Strom TB Kuchroo VK 《Nature immunology》2005,6(5):455-464
The newly identified TIM family of proteins is associated with regulation of T helper type 1 (T(H)1) and T(H)2 immune responses. TIM-1 is genetically linked to asthma and is a receptor for hepatitis A virus, but the endogenous ligand of TIM-1 is not known. Here we show that TIM-4, which is expressed by antigen-presenting cells, is the ligand for TIM-1. In vivo administration of either soluble TIM-1-immunoglobulin (TIM-1-Ig) fusion protein or TIM-4-Ig fusion protein resulted in hyperproliferation of T cells, and TIM-4-Ig costimulated T cell proliferation mediated by CD3 and CD28 in vitro. These data suggest that the TIM-1-TIM-4 interaction is involved in regulating T cell proliferation. 相似文献
106.
Illés Z Waldner H Reddy J Anderson AC Sobel RA Kuchroo VK 《International immunology》2007,19(10):1235-1248
Myelin proteolipid protein (PLP) 139-151 is an immunodominant peptide that induces experimental autoimmune encephalomyelitis (EAE) in H-2(s) SJL/J mice. While PLP 139-151-specific TCR transgenic (tg) 4E3 mice develop fulminant spontaneous disease on the susceptible SJL/J background, spontaneous EAE is dramatically reduced on the H-2(s) congenic B10.S background. On this resistant background, we observed a high frequency of positively selected tg CD4-CD8- (DN) thymocytes and peripheral DN tg T cells. Splenic DN tg T cells responded to anti-CD3 stimulation similarly to CD4+ cells, but proliferative and cytokine responses to PLP 139-151 were blunted, implying that CD4 co-receptor down-regulation modulated T cell responses to the self-antigen in vitro. Adoptive transfer of tg DN CD3hi cells into RAG-deficient wild-type (WT) recipients induced EAE less efficiently than transfer of CD4+ T tg cells indicating the blunted responses of DN tg T cells to self-antigen in vivo. The frequency of tg DN T cells was irrespective of thymic expression of the autoantigen. These data implicate that down-regulation of CD4 co-receptor in the thymus, which is independent from the expression of thymic autoantigen, results in a blunted response to the autoantigen in the periphery and limits the incidence of spontaneous autoimmunity in genetically resistant mice bearing a large autoreactive tg T cell repertoire. 相似文献
107.
108.
Carmona-Bayonas A; Soler IO; Gomez FI; Billalabeitia EG; Saura HP; Tafalla MSA; Diaz MP 《Annals of oncology》2007,18(7):1281
Mitotane is often considered the front-line hormonal therapyof adrenocortical carcinoma (ACC). An illustrative case concerningthis issue and the rationale to ponder other alternatives isreported. A 69 year-old woman, diagnosed with ACC was admittedwith hypertensive crisis, supraventricular tachycardia, congestiveheart-failure, diarrhoea and rabdomyolisis. Two years earlier,she had undergone 相似文献
109.
Ia antigen is a differentiation marker on human eosinophils 总被引:3,自引:0,他引:3
Evidence suggests that the "la-like" or antigen is a differentiation marker that is expressed on early human hematopoietic precursor cells, but is absent on their mature progeny. The eosinophil precursor cell (CFU-EO) is distinct from the granulocyte-monocyte colon-forming cell (CFU-C). We provide data that indicate that the ia antigen is expressed on the human eosinophil colony-forming cells and is absent on mature eosinophils. All CFU-EO were inhibited in the presence of rabbit la antiserum at a titer of 1:30. Cytotoxicity was complement-dependent. The metamyelocytic eosinophil and more mature eosinophil forms did not express the la antigen. 相似文献
110.
The objective of this study was to identify key issues relevant to the development and implementation of a macro-level priority-setting framework (i.e., across broad service areas) within the Calgary Health Region. We used rigorous qualitative methods, including focus groups, meeting observations and interviews to identify views of decision-makers. Key issues relevant to macro-level priority-setting included: application of evidence, incentives, physician involvement, public involvement and application of values. Detailed insight into each of these issues was derived, including how best to handle related barriers to priority-setting in health organizations and important lessons for framework development. These lessons learned should provide insight for similar activity in other jurisdictions. 相似文献