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71.
72.
A study was conducted to systematically evaluate the general public's beliefs and opinions about hypnosis as well as to ascertain the sources of their beliefs. The evaluation was based on four samples representing different ages, socio-economic backgrounds, interests, and geographical locations. A 27 item, two-page questionnaire was developed to evaluate the opinions on a wide variety of topics related to hypnosis and clinical applications of hypnosis. The results indicate that although the different sample groups obtain their information about hypnosis from different sources, their beliefs about hypnosis are remarkably consistent. While the results indicate an interesting mix of ideas about hypnosis, some results indicate that most people have a positive view of the therapeutic benefits, with a vast majority of respondents believing that it reduces the time that is usually required to uncover causes of a person's problems and that hypnotized persons can undergo dental and medical procedures without pain. Other findings indicate that an extremely large proportion of the general public views hypnosis as a powerful tool to recover accurate memories under a variety of conditions including accurate memories as far back as birth or even past lives. These findings may extend and dovetail with the findings that some professionals overestimate the influence of hypnosis on retrieving accurate memories. 相似文献
73.
S Ingvarsson B A Agnarsson B I Sigbjornsdottir J Kononen O P Kallioniemi R B Barkardottir A J Kovatich R Schwarting W W Hauck K Huebner P A McCue 《Cancer research》1999,59(11):2682-2689
Evidence for alteration of the FHIT gene in a significant fraction of breast carcinomas has been reported, in apparent concordance with loss of heterozygosity (LOH) at chromosome region 3p14.2 in breast cancer and benign proliferative breast disease. A significantly higher frequency of LOH at the FHIT locus was reported for BRCA2-/- tumors, possibly due to misrepaired double-strand breaks at this common fragile region. To determine whether such genomic alterations lead to Fhit inactivation, we have assessed the level of Fhit expression by immunohistochemical detection in sporadic tumors and cancers occurring in BRCA2 999del5 carriers. To determine whether Fhit inactivation may have prognostic significance, we have also assessed expression of breast cancer markers and clinical features in sporadic tumors relative to Fhit expression. Of 40 consecutive sporadic breast carcinomas studied for tumor markers, 50% showed reduced Fhit expression. In these sporadic cancers, loss of Fhit expression was not correlated significantly with the presence or absence of other tumor markers. In a study of 58 sporadic and 34 BRCA2 999del5 Icelandic invasive cancers, there was a significant association of LOH at 3p14.2 with reduced expression of Fhit (P = 0.001); also the lower expression of Fhit and higher LOH at 3p14.2 in BRCA2 999del5 tumors relative to sporadic cancers was significant (P = 0.002). Thus, genetic alteration at the fragile site within the FHIT gene leads to loss of Fhit protein in a significant fraction of sporadic breast cancers and a much larger fraction of familial breast cancers with an inherited BRCA2 mutation, consistent with the idea that loss of BRCA2 function affects stability of the FHIT/FRA3B locus. 相似文献
74.
The radicular pain syndrome is a major problem in public health care that can lead to chronic back and leg pain in 30%. Ischalgia
and back pain are the most prominent signs of dorsal root affection. Until now, no clinical or neurophysiological test procedure
exists that evaluates the function of the dorsal root and predicts the prognosis of patients suffering from RPS. We have recently
demonstrated that laser-evoked potentials (LEP) are able to demonstrate dorsal root damage. With this study, we investigated
54 patients with acute radicular symptoms and compared LEP parameters (side to side difference of latency and amplitude, transformed
to a z-score) with their state of health after 3 months to calculate their predictive value for outcome prognosis. Most significantly,
the latency difference between the LEP of the affected dermatome relative to the contralateral healthy dermatome was able
to predict the prognosis. Latency z score above two demonstrates a 91% specificity (33% sensitivity) for a poor outcome at 3 months. A significant relation between
amplitude changes and the main outcome measure could not be shown. Only extreme changes (z score >10) in amplitude show a high specificity for the persistence of ischialgia in particular (specificity 0.94; sensitivity
0.35). All other parameters, such as clinical scores or other LEP parameters, were not able to predict the outcome of patients.
We propose that clinical testing using LEP with latency analysis is a useful tool for estimating the course of disease, so
that patients with poor predictive parameters can be treated more invasively at early disease stages to avoid persistence
of radiculopathy. 相似文献
75.
76.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献
77.
Volumetric rendering techniques: applications for three-dimensional imaging of the hip 总被引:1,自引:0,他引:1
Fishman EK; Drebin B; Magid D; Scott WW Jr; Ney DR; Brooker AF Jr; Riley LH Jr; St. Ville JA; Zerhouni EA; Siegelman SS 《Radiology》1987,163(3):737-738
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images. 相似文献
78.
R von Harsdorf L Hauck F Mehrhof U Wegenka M C Cardoso R Dietz 《Circulation research》1999,85(2):128-136
The heart is a postmitotic organ unable to regenerate after injury. The mechanisms controlling cell cycle arrest in cardiomyocytes are still unknown. Adenoviral delivery of E2F-1 to primary rat cardiomyocytes resulted in an increase in the expression of key cell cycle activators and apoptosis in >90% of the cells. However, insulin-like growth factor I (IGF-I) rescued cardiomyocytes from E2F-1-induced apoptosis. Furthermore, overexpression of E2F-1 in the presence of IGF-I induced the specific downregulation of total p21(CIP1) and p27(KIP1) protein levels and their dissociation from cyclin-dependent kinases (cdks). In contrast, p16(INK4) and p57(KIP2) protein levels and their association with cdks remained unaltered. The dissociation of p21(CIP1) and p27(KIP1) from their cdk complexes correlated well with the activation of cdk2, cdk4, and cdk6 and the release from cell cycle arrest. Under these circumstances, the number of cardiomyocytes in S phase rose from 1.2% to 23%. These results indicate that IGF-I renders cardiomyocytes permissive for cell cycle reentry. Finally, the specific downregulation of p21(CIP1) and p27(KIP1) further suggests their key role in the maintenance of cell cycle arrest in cardiomyocytes. 相似文献
79.
We develop two estimators of a common odds ratio psi for designs in which the investigator randomly assigns each of two clusters to interventions within strata. The estimators rely on an empirical adjustment for clustering to provide improved estimators of psi relative to the standard Woolf and Mantel-Haenszel estimators, respectively. The results of a simulation study show that the suggested adjustment improves the accuracy of both of these well-known estimators under conditions likely to arise in practice. We find the clustered Woolf estimator as particularly effective in terms of mean squared error reduction. We also discuss interval estimation. 相似文献
80.
Cao J Prisinzano TE Okunola OM Kopajtic T Shook M Katz JL Newman AH 《ACS medicinal chemistry letters》2010,2(1):48-52
A series of modafinil (1) analogues was synthesized wherein 1) para-halo-substitutents were added to the aryl rings, 2) the sulfoxide function was removed, and 3) the primary amide group was replaced with secondary and tertiary amides and amines to investigate the effects of these chemical modifications on DAT, SERT and NET binding. In addition, the locomotor-stimulant effects in mice of (±)-modafinil (1), its R- and S-enantiomers and its para-chloro sulfinylacetamide analogue (5c) were compared to those of cocaine. 相似文献