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61.
Contingency management (CM) is a scientifically based treatment approach typically employed in substance abuse treatment settings
to reinforce drug abstinence, counseling attendance, completion of activities, or other treatment goals. Although the application
of CM to HIV management has few published studies, it shows promise as an intervention for HIV-related behaviors. CM interventions
such as voucher reinforcement, prize systems, and cash incentives can be used to reduce HIV risk behaviors and to improve
HIV medication adherence. CM programs have wide applicability to HIV prevention and management in clinical and community settings
and can be implemented as stand-alone techniques or in combination with other interventions. 相似文献
62.
63.
Numerous neuroimaging studies have attempted to identify how the brain responds to stimuli mimicking dental treatment in normal non‐phobic individuals. However, results were sometimes inconsistent due to small sample sizes and methodological variations. This meta‐analysis employs standardized procedures to summarize data from previous studies to identify brain regions that were consistently activated across studies, elicited by stimuli such as pictures, sounds, or audiovisual footage mimicking those encountered during dental treatments. A systematic literature search was carried out using PubMed and Scopus. The meta‐analysis analyzed data from 120 healthy subjects from seven neuroimaging studies. We assessed the risk of bias among the included studies with the Risk of Bias Assessment Tool for Nonrandomized Studies. One study appeared to have a high risk of selection bias, whereas the others were considered to have a low risk of bias. Results revealed three clusters of activation with cluster sizes ranging from 768 mm3 to 1,424 mm3. Stimuli mimicking dental treatment consistently activated the bilateral anterior insula; right dorsal anterior cingulate, putamen, and medial prefrontal cortex; and left claustrum. This study confirmed that audio and/or visual stimuli mimicking dental treatment consistently activated the fear‐related brain regions among healthy subjects, mostly consistent with activations from general anxiety but without the involvement of the amygdala. 相似文献
64.
A. Gregory Sorensen Andrew L. Tievsky Leif Ostergaard Robert M. Weisskoff Bruce R. Rosen 《Journal of magnetic resonance imaging : JMRI》1997,7(1):47-55
Contrast agents have greatly expanded the role of MR imaging (MRI) to allow assessment of physiologic, or “functional,” parameters. Although activation mapping generally does not require contrast agents, other forms of functional MRI, including mapping of cerebral hemodynamics (eg, perfusion imaging), are best done with the use of contrast agents. Serial echo planar images are obtained after bolus injection of lanthanide chelates. Application of susceptibility contrast physics and standard tracer kinetic principles permits generation of relative cerebral blood volume maps. Deconvolution of cerebral blood flow and mean transit time parameters is also possible within technical limitations. By using diffusion and perfusion pulse sequences, an imaging correlate to the ischemic penumbra can be identified. Functional MRI perfusion imaging of intraaxial tumors is analogous to positron emission tomography for delineation of metabolic activity, yet may be even more sensitive to neovascularity and possesses improved image quality. Clinical applications include biopsy site selection and postirradiation follow-up. Further improvements in data analysis and map generation techniques may improve diagnostic accuracy and utility. 相似文献
65.
E E Stafford S Masri K Sorensen 《The Southeast Asian journal of tropical medicine and public health》1976,7(3):405-410
A survey for blood and intestinal parasites was carried out in the municipality of Gorontalo on the Minahasa peninsula of North Sulawesi. A total of 156 stool specimens were obtained from 83 males and 73 females. Trichuris trichiura, Ascaris lumbricoides, hookworm, unidentified dicrocoeliid-like ova and Entamoeba coli, in that order, were the most common intestinal parasites detected. Other intestinal parasites found less frequently were Entamoeba histolytica, Iodamoeba bütschlii, Endolimax nana, Giardia lamblia, Enterobius vermicularis and Chilomastix mesnili. Brugia malayi microfilaremiar were detected in 6% and Plasmodium falciparum in less than 1% of the population sampled. 相似文献
66.
J. Sellner M. Boggild M. Clanet R. Q. Hintzen Z. Illes X. Montalban R. A. Du Pasquier C. H. Polman P. S. Sorensen B. Hemmer 《European journal of neurology》2010,17(8):1019-1032
Background and purpose: Neuromyelitis optica (NMO) or Devic′s disease is a rare inflammatory and demyelinating autoimmune disorder of the central nervous system (CNS) characterized by recurrent attacks of optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM), which is distinct from multiple sclerosis (MS). The guidelines are designed to provide guidance for best clinical practice based on the current state of clinical and scientific knowledge. Search strategy: Evidence for this guideline was collected by searches for original articles, case reports and meta‐analyses in the MEDLINE and Cochrane databases. In addition, clinical practice guidelines of professional neurological and rheumatological organizations were studied. Results: Different diagnostic criteria for NMO diagnosis [Wingerchuk et al. Revised NMO criteria, 2006 and Miller et al. National Multiple Sclerosis Society (NMSS) task force criteria, 2008] and features potentially indicative of NMO facilitate the diagnosis. In addition, guidance for the work‐up and diagnosis of spatially limited NMO spectrum disorders is provided by the task force. Due to lack of studies fulfilling requirement for the highest levels of evidence, the task force suggests concepts for treatment of acute exacerbations and attack prevention based on expert opinion. Conclusions: Studies on diagnosis and management of NMO fulfilling requirements for the highest levels of evidence (class I–III rating) are limited, and diagnostic and therapeutic concepts based on expert opinion and consensus of the task force members were assembled for this guideline. 相似文献
67.
Baker LL; Hajek PC; Burkhard TK; Dicapua L; Leopold GR; Hesselink JR; Mattrey RF 《Radiology》1987,163(1):89-92
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum. 相似文献
68.
Thomas Benner Andr J.W. van der Kouwe John E. Kirsch A. Gregory Sorensen 《Magnetic resonance in medicine》2006,56(1):204-209
Although the magnetic field of an MR scanner is very stable under little or no load, it can become less stable under heavy‐duty cycle conditions, such as in diffusion tensor imaging (DTI). Uncorrected, such field drifts lead to an apparent image shift along the phase‐encoding direction and decreasing effectiveness of fat saturation pulses. A method is presented to adjust the center frequency of all RF pulses and the receiver in real time during the acquisition. No data postprocessing or changes to the sequence timing are necessary. In vivo acquisitions were performed to assess the prolonged effectiveness of fat saturation. Field drifts of approximately 2.5 Hz/min were measured and corrected during DTI acquisitions at b‐values of up to 3000 s/mm2. The effectiveness of fat saturation diminished over the duration of an 18‐min acquisition when the drift was left uncorrected. The proposed method corrects for apparent image shift and ensures continuously effective fat saturation over the duration of an acquisition. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
69.
Henrik Kahr Mathiesen Thomas Tscherning Per Soelberg Sorensen Henrik B W Larsson Egill Rostrup Olaf B Paulson Lars G Hanson 《Magnetic resonance in medicine》2005,53(4):750-759
MR spectroscopy (MRS) provides information about neuronal loss or dysfunction by measuring decreases in N-acetyl aspartate (NAA), a metabolite widely believed to be a marker of neuronal viability. In multiple sclerosis (MS), whole-brain NAA (WBNAA) has been suggested as a marker of disease progression and treatment efficacy in treatment trials, and the ability to measure NAA loss in specific brain regions early in the evolution of this disease may have prognostic value. Most spectroscopic studies to date have been limited to single voxels or nonlocalized measurements of WBNAA only, and longitudinal studies have often been hampered by standardization and reproducibility problems. Multi-slice echo-planar spectroscopic imaging (EPSI) is presented as a promising alternative to single-voxel or nonlocalized spectroscopy for obtaining global metabolite estimates in MS. In the same session, measurements of metabolites in specific brain areas chosen after image acquisition (e.g., normal-appearing white matter (NAWM), gray matter (GM), and lesions) can be obtained. The identification and exclusion of regions that are inadequate for spectroscopic evaluation in global assessments can significantly improve quality and reproducibility, as demonstrated by a low within-subject variance in healthy controls. The reproducibility of the technique makes it a promising tool for future longitudinal spectroscopic studies of MS. 相似文献
70.
Hanne B. Albert Joan S. Sorensen Berit Schiott Christensen Claus Manniche 《European spine journal》2013,22(4):697-707