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1.
This study evaluated the effect of new motions of the motor TriAuto ZX2 on the cyclic fatigue of endodontic instruments. Vortex Blue 35.06 instruments were divided into four groups (n = 10) and tested for fatigue in a curved artificial canal (90° and 2 mm radius) using the following motions: continuous rotation (CR), Optimum Torque Reverse (OTR) set at 180° and the Optimum Glide Path (OGP), which was tested at 90° and 240°. The time to fracture (TTF) and the lengths of the fractured fragments were recorded. The mean TTF was significantly different among the groups (anova , P < 0.05): OGP 90° (213.39 ± 27.45), OTR 180° (121.24 ± 17.03), OGP 240° (45.24 ± 5.61) and CR (8.43 ± 1.27). Weibull analysis confirmed the shortest life expectancy for CR and the longest survival for OGP at 90°. The resistance to fatigue was affected by motions and pre‐set angles. The proprietary movements that are currently available for endodontic instruments were classified according to their kinematics.  相似文献   
2.
The purpose of the study was to compare an interview measure of quality of object relations to questionnaire and interview measures of recent interpersonal functioning with respect to the prediction of therapeutic alliance and psychotherapy outcome. The sample consisted of 64 patients who had received approximately 20 sessions of short-term individual psychotherapy within a controlled, clinical-trial investigation. Ratings of therapeutic alliance were provided independently by the patient and the therapist after each session. Outcome measures, which were provided by three sources (patient, therapist, and independent assessor), covered the areas of interpersonal functioning, psychiatric symptomatology, self-esteem, and life satisfaction. Quality of object relations, which characterizes the patient's lifelong pattern of relationships, was the best predictor. It was significantly related to patient-rated and therapist-rated therapeutic alliance and to patient improvement of both general symptomatology and specific target problems. The study also replicated previous studies that have reported significant relationships between therapeutic alliance and therapy outcome. The advantages of pretherapy predictors of therapy outcome, such as quality of object relations, are discussed.  相似文献   
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4.
Over the past 10 years, arteriography has become a well-established technique for the diagnosis of acute lower gastrointestinal bleeding, but not particularly for rectal bleeding. However, to the authors' knowledge, the technique of middle hemorrhoidal artery embolization has rarely been reported in the literature. In the present report, three patients with life-threatening rectal bleeding are presented, which was controlled by superselective embolization of the middle hemorrhoidal artery or selective embolization of the internal iliac artery as a last resort.  相似文献   
5.
Case report Leptomeningeal involvement in diffuse intrinsic brain stem gliomas is rarely diagnosed clinically and in majority of the instances diagnosed only on postmortem examination. We report two cases of diffuse pontine glioma diagnosed clinicoradiologically and treated with conventional radiotherapy.Observations On follow-up, both patients showed clinical features suggestive of meningeal spread although imaging for pontine tumor showed stable disease. Leptomeningeal disease in the spine was confirmed on imaging and in one case by cerebrospinal fluid examination also. During the follow-up of patients with pontine glioma, the possibility of leptomeningeal involvement must be borne in mind.  相似文献   
6.
This study was undertaken in order to compare the interphase and metaphase cytogenetics of 28 patients with ETV6/RUNX1 positive acute lymphoblastic leukemia, at diagnosis and relapse. The median time to relapse was 26 months. The significant fusion positive population heterogeneity revealed at interphase by a commercial probe for ETV6/RUNX1 fusion has not been described before. Six diagnostic samples had a single abnormal population; others had up to five each, which differed in the numbers of RUNX1 signals, and in the retention or loss of the second ETV6 signal. In contrast, the number of fusion signals was more constant. At relapse, there were fewer populations; the largest or unique clone was sometimes a re-emergence of a minor, diagnostic one, with a retained copy of ETV6 and the most RUNX1 signals. Abnormal, fusion negative clones were identified in bone marrow samples at extra-medullary relapse. Variant three or four-way translocations, which involved chromosomes 12 and 21, were prominent among the complex rearrangements revealed by metaphase FISH. The frequency of their occurrence at diagnosis and reappearance at relapse, sometimes accompanied by minor clonal evolution, was another new observation. Other recurrent cytogenetic features included a second copy of the fusion signal in six cases, partial duplication of the long arm of the X chromosome in two cases, and trisomy 10 in three cases. In comparing our data with previously reported cases, a picture is beginning to emerge of certain diagnostic features, which may provide circumstantial evidence of an increased risk of relapse.  相似文献   
7.
Cytokines in the stools of children with complicated shigellosis.   总被引:1,自引:1,他引:1       下载免费PDF全文
The pathogenesis of the systemic complications, leukemoid reaction and hemolytic uremic syndrome, associated with Shigella dysenteriae type 1 infection is not well understood. The excessive production of proinflammatory cytokines, including tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6), has been suggested as a possible factor. We measured IL-6 and TNF-alpha in stools of 56 children with S. dysenteriae 1 infection and 29 children without any apparent infection, all age 12 to 60 months. Sixteen children with S. dysenteriae 1 infection had leukemoid reaction or hemolytic uremic syndrome (complicated shigellosis), while the others did not (uncomplicated shigellosis). Stool IL-6 and TNF-alpha concentrations were higher in children with uncomplicated shigellosis than in children with complicated shigellosis (P = 0.009 and < 0.001, respectively) or in uninfected children (P < 0.001). It is concluded that complicated infection is not associated with higher concentrations of the proinflammatory cytokines IL-6 and TNF-alpha in stool.  相似文献   
8.
A monoclonal antibody, ICT11, specific for the toxin of enterotoxigenic Bacteroides fragilis (ETBF) neutralized the cytotoxic effect of the toxin on human colonic cell line HT-29/C1. In an evaluation using 115 diarrheal stool specimens and culture as the "gold standard," the assay showed a sensitivity of 85% and a specificity of 100%. An ICT11-based sandwich enzyme-linked immunosorbent assay showed a sensitivity of 100% and a specificity of 98% for direct detection of toxin from stool samples compared with those of culture. Thus, ICT11-based assays will be useful for screening for ETBF.  相似文献   
9.
The bundle-forming pilus (BFP) produced by enteropathogenic Escherichia coli (EPEC) is associated with the presence of a large EPEC adherence factor plasmid and the formation of localized adherence clusters on tissue culture cells. Three mouse monoclonal antibodies (ICA2, ICA3, and ICA4) were produced against BFP purified from EPEC B171 (O111:NM). These monoclonal antibodies reacted in immunoblots with different epitopes of the 19.5-kDa bundlin subunit of BFP of heterologous EPEC. These reagents could serve as diagnostic tools for the identification of EPEC as well as for studying the role of BfpA in the interaction of EPEC with eukaryotic cells.  相似文献   
10.
The objective of this study is to design a new apparatus to allow the control of the magnitude and frequency of dynamic stretch applied uniformly to cells cultured on a silicon elastic membrane. The apparatus is designed to produce equi-biaxial dynamic stretches with area changes ranging from 0% to 55% and frequencies ranging from 0 to 2 Hz. Homogeneous finite strain analysis using triangles of markers was performed to compute the symmetric two-dimensional Lagrangian strain tensor on the membrane. Measurements of strain in both static and dynamic conditions showed that the shear component of the strain tensor (Erc) was near zero, and that there was no significant difference between radial (Err) and circumferential (Ecc) components, indicating the attainment of equi-biaxial strain. Bovine aortic endothelial cells were transiently transfected with a chimeric construct in which the luciferase reporter is driven by TPA-responsive elements (TRE). The transfected cells cultured on the membrane were stretched. The luciferase activity increased significantly only when the cells were stretched by 15% or more in area. Cells in different locations of the membrane showed similar induction of luciferase activities, confirming that strain is uniform and equi-biaxial across the membrane. © 1998 Biomedical Engineering Society. PAC98: 8780+s, 8745-k, 8722-q  相似文献   
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