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11.
pp59v-rel exists in association with specific cellular proteins within lymphoid cells transformed by reticuloendotheliosis virus (REV-T). These include the cellular rel homolog (p75c-rel) as well as a 40-kDa avian homolog to I kappa B. The brief exposure of REV-T-transformed lymphoid cells to micromolar concentrations of ZnSO4 induces profound alterations within these protein complexes. Most of the constituents of the rel protein complexes (to include pp59v-rel, p75c-rel, and p115) translocate from the cytosol to the nucleus. This system has been used to characterize the molecular events that accompany the activation of rel protein complexes. The level of phosphorylation increases on three proteins within these complexes: pp59v-rel, p75-c-rel, and pp40. The degree of phosphorylation on pp59v-rel is such that its relative mass increases 3 to 6 kDa when resolved by SDS-polyacrylamide gel electrophoresis. pp59v-rel is phosphorylated on serine and threonine residues predominantly within a single domain of 17.5 kDa. Similarly, p75c-rel exhibits a corresponding increase in its relative mass with increased phosphorylation. The increased phosphorylation of pp40 is accompanied by its dissociation from the cytosolic rel protein complexes. These observations draw parallels with the induction of the NF-kappa B trans-activating factor. 相似文献
12.
MA Sevick B Piraino S Sereika T Starrett C Bender J Bernardini S Stark LE Burke 《Journal of renal nutrition》2005,15(3):304-311
OBJECTIVE: The purpose of this study was to pilot test an intervention to enhance the adherence of study participants to the hemodialysis dietary regimen. DESIGN: A single case study design was used to examine the potential effectiveness of the intervention over a 4-month period of time. SETTING: A dialysis center in southwestern Pennsylvania. PATIENTS: Of the five individuals entered into the study, one was male and four were female, four were black, and one was white. Participants were 63 to 70 years of age, and had been receiving dialysis for a median of 36 months (range, 18 to 84 months). INTERVENTION: The intervention included counseling to enhance self-efficacy, by a renal dietitian, paired with personal digital assistant-based dietary self-monitoring. Participants met twice per week with interventionists during the first 6 weeks, weekly during the second 6-week period, and biweekly in the final 4-week period. MAIN OUTCOME MEASURES: Monthly laboratory data regarding serum albumin, potassium, and phosphorus levels; Kt/V; and data on average monthly interdialytic weight gain were abstracted from the participants' medical records. C-reactive protein level was determined at baseline and at 4 months. RESULTS: Four of five study participants had an increase in serum albumin level from baseline to their final measurement, and one participant maintained a stable albumin level. Four of five participants also experienced a small increase in serum phosphorus level. Mixed results were obtained with regard to serum potassium and average monthly interdialytic weight gain. CONCLUSIONS: Because of the small sample and single case study design, caution must be used in drawing firm conclusions from this study. Data suggest that the intervention may result in improved dietary intake and improved serum albumin levels. With increased dietary intake, serum phosphorus levels may increase. Additional research is needed to determine the potential efficacy and cost-effectiveness of this intervention for improving dietary adherence. 相似文献
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14.
Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
15.
In the past decade, several studies have used scaling and clustering techniques to document semantic storage deficits in patients with Alzheimer's disease and in schizophrenia. In this article the authors argued that many of the conclusions drawn from these studies are unjustified by the data. They reviewed the methodology used in these studies and presented data from simulation studies to further investigate the validity of their conclusions. The authors elaborate on the criteria needed to exclude alternative accounts of the data and present empirical data from patients with Alzheimer's disease and normal control participants to demonstrate that analyses of the patients' proximity data do not provide unambiguous evidence for a generalized semantic storage deficit. 相似文献
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18.
T W Huber S Storms P Young L E Phillips T E Rogers D G Moore R P Williams 《Journal of clinical microbiology》1983,17(3):405-409
Seroreactivity of sera from 109 patients with first-infection primary syphilis was 98.2% in the fluorescent treponemal antibody absorption test, 92.7% in the rapid plasma reagin 18-mm circle card test, 72.5% in the microhemagglutination test (MHA-TP), and 72.5% in the Venereal Disease Research Laboratory test. Seroreactivity of sera from 18 patients with primary syphilis with documented previous infection(s) was 100% in the fluorescent treponemal antibody absorption test, the rapid plasma reagin 18-mm circle card test, and the MHA-TP test and 88.9% in the Venereal Disease Research Laboratory test. The MHA-TP test failed to confirm reactivity in 13 of 79 sera which were reactive in the Venereal Disease Research Laboratory test and in 24 of 101 sera which were reactive in the rapid plasma reagin 18-mm circle card test. Testing another production lot of MHA-TP reagents resulted in even poorer correlation. The reactivity of the MHA-TP test in primary syphilis appeared to vary with the sensitivity of the production lot of reagents. 相似文献
19.
The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry 总被引:8,自引:1,他引:8
Nistico L; Buzzetti R; Pritchard LE; Van der Auwera B; Giovannini C; Bosi E; Larrad MT; Rios MS; Chow CC; Cockram CS; Jacobs K; Mijovic C; Bain SC; Barnett AH; Vandewalle CL; Schuit F; Gorus FK; Tosi R; Pozzilli P; Todd JA 《Human molecular genetics》1996,5(7):1075-1080
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus
is determined by a combination of environmental and genetic factors, which
include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin
gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2
cannot explain the clustering of type 1 diabetes in families, and a role
for other genes is inferred. In the present report we describe linkage and
association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte
associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong
candidate gene for T cell- mediated autoimmune disease because it encodes a
T cell receptor that mediates T cell apoptosis and is a vital negative
regulator of T cell activation. In addition, we provide supporting evidence
that CTLA-4 is associated with susceptibility to Graves' disease, another
organ- specific autoimmune disease.
相似文献
20.
MICHÈLE COUTARD MARY OSBORNE-PELLEGRIN 《International journal of experimental pathology》1996,77(2):53-62
Microscopic aneurysmal-like structures (ALS) develop spontaneously in the convoluted rat testicular artery and have been previously proposed as a model relevant to cerebral aneurysms. The effect of defects in connective tissue fibres on ALS formation was investigated by microscopy using two approaches: (i) the study of the effect of β-aminopropionitrile (BAPN), an inhibitor of the cross-linking of elastic and collagen fibres, on the incidence, size and morphology of ALS in spontaneously hypertensive rats (SHR) and their normotensive controls (WKY). The straight spermatic artery was studied for comparison. (ii) The determination of the incidence of spontaneous ALS in Brown Norway (BN) and Long Evans (LE) rats which are highly susceptible (BN) or resistant (LE) to the spontaneous rupture of the arterial internal elastic lamina. (i) BAPN increased the number and size of ALS in SHR and WKY rats and had no effect on the straight spermatic artery and (ii) ALS were more numerous and of greater size in BN than in LE rats. Taken together, these results show that defective connective tissue fibres may favour the formation and induce the enlargement of aneurysmal-like structures. By analogy, these data suggest that a lack of connective tissue fibre integrity may be of importance in cerebral aneurysm formation and development. 相似文献