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排序方式: 共有1750条查询结果,搜索用时 15 毫秒
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2.
The value of different resistance parameters in distinguishing biopsy-proved dysfunction of renal allografts 总被引:3,自引:2,他引:1
Frauchiger B.; Bock A.; Eichlisberger R.; Landmann J.; Thiel G.; Mihatsch M. J.; Jager K. 《Nephrology, dialysis, transplantation》1995,10(4):527-532
The data concerning the value of duplex sonography in diagnosingparenchymatous renal allograft dysfunction are controversial.Most early studies did not take into consideration the manyfactors influencing resistance parameters. We therefore performeda prospective, biopsy-controlled study with exclusion of allknown sources of error regarding resistance parameters. Furthermorewe investigated the value of a new resistance parameter, thesystolic deceleration percentage. Forty-seven duplex sonographicstudies were performed on 43 patients (30 male, 13 female, medianage 47 years, range 770). Fourteen studies were doneon normally functioning grafts (control group) an average of33 days after transplantation. Thirty-three studies were performedon dysfunctional grafts immediately prior to biopsy. Graftswhich had been transplanted more than a year previously or withvascular findings or any other clinical or sonographic pathologyprobably explaining function deterioration were excluded. Inall patients, the resistive index (RI), pulsatility index (PI)and systolic deceleration percentage (DP) were calculated inthe main renal artery and in the interlobar artery. Of the 33grafts with dysfunction, nine had vascular rejection (VR), 11interstitial rejection (IR), 11 cyclosporin A toxicity (CAT)and two other histologies (OR). The mean RI in normal grafts(NO) was 0.71±0.06 in the main artery and 0.68±0.06in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18,in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01.For PI, the values were 1.45±0.23 and 1.41±0.28(NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26(CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DPwe calculated 28±5% and 29±6% (NO), 43±14%and 36±6% (VR), 29±9% and 27±9% (IR), 31±8%and 32±7% (CAT ) and 32±4% and 28±3% (OR).The sensitivity/specificity for VR with a cutoff mean+2 SD was0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It wasconcluded that:(1) despite the high selection of our patientgroup, diagnostic accuracy of duplex sonography for diagnosingparenchymatous function disorder in renal allograft remainsinsufficient; (2) in vascular rejection only, the resistanceparameters differ significantly from the values of normal allografts;(3) the higher the cutoff of resistance parameters, the betterthe specificity and the worse the sensitivity for diagnosingvascular rejection; (4) of all investigated resistance parameters,the RI is the most practical due to a simple measurement technique. 相似文献
3.
Jos F M de Jonghe Kees J Kalisvaart Marty Dijkstra Huib van Dis Ralph Vreeswijk Martin G Kat Piet Eikelenboom Tjeerd van der Ploeg Willem A van Gool 《The American journal of geriatric psychiatry》2007,15(2):112-121
OBJECTIVES: The authors investigated prodromal delirium symptoms in elderly patients undergoing hip surgery. METHODS: This was a prospective cohort study in the setting of a large medical school-affiliated general hospital in Alkmaar, The Netherlands. Participants were patients undergoing hip surgery aged 70 and older at risk for delirium. Before surgery, patients were randomized to low-dose prophylactic haloperidol treatment or placebo. Daily assessments were based on patient interviews with the Mini-Mental State Examination and Digit Span test. The Delirium Rating Scale-Revised (DRS-R-98) was used to measure early symptoms during the prodromal phase before the onset of delirium. RESULTS: Data of 66 patients with delirium were compared with those of 35 at-risk patients who did not develop delirium: 14 of 66 patients (21%) had delirium on the day of surgery or early the day after, 32 of 66 (48%) on the second day, 14 of 66 on the third, and six of 66 (9%) on the fourth. The average DRS-R-98 total scores on day -4 to day -1 before delirium were 1.9 for the comparison group patients and 5.0, 4.3, 5.8, and 10.7 for patients with postoperative delirium. Multivariate analysis showed that the early symptoms memory impairments, incoherence, disorientation, and underlying somatic illness predict delirium. CONCLUSIONS: Most elderly patients undergoing hip surgery with postoperative delirium already have early symptoms in the prodromal phase of delirium. These findings are potentially useful for screening purposes and for optimizing prevention strategies targeted at reducing the incidence of postoperative delirium. 相似文献
4.
Thirty-one consecutive patients with primary non-Hodgkin's lymphoma of the stomach were studied to outline the spectrum of endoscopic abnormalities. The 17 men and 14 women had a median age of 65 years. There were 22 patients in stage I and 9 in stage II. Three endoscopic patterns were recognized: diffuse infiltration (9), ulceration (9) and polypoid lesions (13). There was no apparent correlation between the endoscopic appearance and the grading or subtype of the malignancy. Local recurrence did not occur once complete remission was obtained. The disease-free 5-year survival rate was 45%. Recognition of these endoscopic patterns may lead to earlier detection and, hopefully, improved survival. 相似文献
5.
Simultaneous Detection of 15 Human Cytokines in a Single Sample of Stimulated Peripheral Blood Mononuclear Cells 下载免费PDF全文
Wilco de Jager Henk te Velthuis Berent J. Prakken Wietse Kuis Ger T. Rijkers 《Clinical and Vaccine Immunology : CVI》2003,10(1):133-139
Cytokines secreted by cells of the immune system can alter the behavior and properties of immune or other cells. At a site of inflammation, sets of cytokines interact with immune cells, and their combined effect is often more important than the function of one isolated component. Conventional techniques, such as enzyme-linked immunosorbent assays, generally require large quantities of cells to characterize a complete cytokine profile of activated lymphocytes. The Bio-Plex system from Bio-Rad Laboratories combines the principle of a sandwich immunoassay with the Luminex fluorescent-bead-based technology. We developed a multiplex cytokine assay to detect different cytokines simultaneously in culture supernatant of human peripheral blood mononuclear cells stimulated with antigen and with mitogen. Fifteen human cytokines (interleukin 1α [IL-1α], IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-15, IL-17, IL-18, gamma interferon, and tumor necrosis factor alpha) were validated with a panel of healthy individuals, rheumatoid arthritis patients, and juvenile idiopathic arthritis patients. Comparing the multiplex assay with a regular enzyme-linked immunosorbent assay technique with this donor panel resulted in correlation coefficients for all cytokines ranging from 0.75 to 0.99. Intra-assay variance proved to be less then 10%, whereas interassay variability ranged between 10 and 22%. This multiplex system proved to be a powerful tool in the quantitation of cytokines. It will provide a more complete picture in differences between activated lymphocyte cytokine profiles from healthy individuals and those from patients with chronic inflammatory diseases. 相似文献
6.
Evidence of a long QT founder gene with varying phenotypic expression in South African families. 下载免费PDF全文
T de Jager C H Corbett J C Badenhorst P A Brink V A Corfield 《Journal of medical genetics》1996,33(7):567-573
We report five South African families of northern European descent (pedigrees 161, 162, 163, 164, and 166) in whom Romano-Ward long QT syndrome (LQT) segregates. The disease mapped to a group of linked markers on chromosome 11p15.5, with maximum combined two point lod scores, all generated at theta = 0, of 15.43 for the D11S922, 10.51 for the D11S1318, and 14.29 for the tyrosine hydroxylase (TH) loci. Recent studies have shown that LQT is caused by an Ala212Val mutation in a potassium channel gene (KVLQT1) in pedigrees 161 to 164. We report that the same mutation is responsible for the disease in pedigree 166. Haplotype construction showed that all the families shared a common haplotype, suggesting a founder gene effect. DNA based identification of gene carriers allowed assessment of the clinical spectrum of LQT. The QTc interval was significantly shorter in both carriers and non-carriers in pedigree 161 (0.48 s and 0.39 s, respectively) than the same two groups in pedigree 161 (0.52 s and 0.42 s, respectively). The spectrum of clinical symptoms appeared more severe in pedigree 162. The possible influence of modulating genetic factors, such as HLA status and sex of family members, on the expression of an LQT founder gene is discussed. 相似文献
7.
Shebzukhov YV Koroleva EP Khlgatian SV Lagarkova MA Meshcheryakov AA Lichinitser MR Karbach J Jager E Kuprash DV Nedospasov SA 《Immunology letters》2005,100(1):88-93
Thymidylate synthase (TYMS), the critical enzyme for DNA synthesis and a target for chemotherapy, was recently characterized as an oncogene and a potential target for specific immunotherapy. Here we report TYMS-specific antibody response in a fraction of colon cancer patients. Humoral immune response to TYMS is induced by chemotherapy using TYMS inhibitors, such as 5-fluorouracil (5-FU), and may be associated with tumor burden. Therefore, TYMS may serve as a useful serological biomarker for monitoring the course of disease and treatment in cancer patients. 相似文献
8.
In supplementation tests both middle component (M)-RNA and bottom component (B)-RNA of cowpea mosaic virus mutant N142 were shown to carry mutations affecting local symptoms in bean and cowpea. The M- and B-RNA mutations were separately incorporated into the two reciprocal hybrids of N142 and wild-type Sb, designated as M142BSb and MSbV142. Mixtures of the two hybrids induced normal local symptoms in bean and cowpea as a result of reassortment of components. This was also the case with a mixture of MSbV142 and mutant N123. The latter mutant was earlier shown to contain a M-RNA mutation for defective symptom expression in bean and cowpea. Although both M142BSb and N123 carried M-RNA mutations, mixtures of these isolates induced normal local symptoms. Subculturing showed no wild-type virus to be present in the inoculated leaves. Thus, intrastrand complementation was assumed to result in restoration of normal symptom production. We conclude that the results of genetic mixing experiments with multicomponent plant viruses must be interpreted cautiously. Subculturing experiments should be performed to determine whether restoration of wild-type symptoms results from exchange of nonmutated components or from intrastrand complementation. 相似文献
9.
Immerstrand C Jager EW Magnusson KE Sundqvist T Lundström I Inganäs O Peterson KH 《Medical & biological engineering & computing》2003,41(3):357-364
Melanophores are dark-brown pigment cells located in the skin of amphibia, fish and many invertebrates. The skin colour of
these organisms is regulated by the translocation of pigment organelles, and the pigment distribution can be altered by external
stimuli. The ability to change colour in response to stimuli makes these cells of interest for biosensing applications. It
was investigated whether pigment aggregation in Xenopus laevis melanophores can be detected by impedance measurements performed
in transparent microvials. The results show that cell attachment, cell spreading and pigment aggregation all resulted in impedance
changes, seen particularly at the highest frequency tested (10 kHz). The mechanisms behind the impedance changes were investigated
by the addition of latrunculin or melatonin, both of which cause pigment aggregation. The latrunculin-induced aggregation
was associated with cell area decrease and filamentous actin (F-actin) breakdown, processes that can influence the impedance.
Lack of F-actin breakdown and an increase in cell area during melatonin-induced aggregation suggest that some other intracellular
process also contributes to the impedance decrease seen for melatonin. It was shown that impedance measurements reflect not
only cell attachment and cell spreading, but also intracellular events. 相似文献
10.