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11.
Yihong Yang Venkata S. Mattay Daniel R. Weinberger Joseph A. Frank Jeff H. Duyn 《Journal of magnetic resonance imaging : JMRI》1997,7(2):371-375
To perform true three-dimensional activation experiments in the human brain, dedicated localized echo-volume imaging (L-EVI) methods were developed. Three-dimensional acquisition allows generation of activation maps with minimal vascular enhancement related to inflow effects. The rapid acquisition of the L-EVI (~100 msec) reduces signal instabilities caused by motion, facilitating the detection of the small intensity changes expected with brain activation. Single-shot L-EVI was performed on normal volunteers at 1.5 T, imaging a three-dimensional predefined volume (240 × 45 × 45 mm3) in the superior portion of the brain with a spatial resolution of 3.75 × 5 × 5 mm3. Increased brain coverage was achieved with a multi-volume imaging (three-shot) version, which simultaneously achieved effective suppression of signals from cerebrospinal fluid. In addition, both asymmetric spin-echo (ASE) and spin-echo (SE) versions of the technique were used to detect blood oxygenation level dependent (BOLD) signal changes in the motor cortex with a finger-tapping paradigm. Images obtained by the L-EVI sequence were qualitatively comparable to standard multislice two-dimensional echo-planar images. Both ASE and SE functional MRI (fMRI) experiments showed consistent activation in the contralateral primary sensorimotor cortex. Furthermore, significant differences in location and magnitude of activation was observed between the two methods, confirming theoretical predictions. 相似文献
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A new patellar angle is described in lateral radiographs of the knee joint. One line is drawn along the articular surface of the patella and another from the end of the inferior articular cartilage to the patellar apex. The angle formed by these two lines averaged 33° in 68 knees joints afflicted with Osgood-Schlatter disease and 47° in 71 age-matched controls and 198 adult controls. The small angle in Osgood-Schlatter disease is proposed to be an important factor in the pathogenesis of the traction apophysitis. 相似文献
14.
V K Yeragani R Pohl R Balon C Ramesh D Glitz P Weinberg B Merlos 《Neuropsychobiology》1992,26(1-2):27-32
Recently, heart rate (HR) variability has received considerable attention, and a decreased HR variability has been linked to a significant risk of cardiovascular illness. We have previously reported such a decreased variability in panic disorder patients. In this study, we report on HR variability in 12 depressed and 6 panic disorder patients at baseline and 1 and 3 weeks of treatment with imipramine as measured by the standard deviation, mean consecutive difference and the standard deviation of the mean consecutive difference of the R-R intervals in supine, supine deep breathing and standing postures. In all subjects, imipramine (mean dose: 70 mg/day) produced a significant decrease in heart rate variability at week 3 as measured by the above variables. This decrease in HR variability during imipramine treatment is probably due to its anticholinergic effects. 相似文献
15.
Surgery in tropical pancreatitis: analysis of risk factors. 总被引:2,自引:0,他引:2
Over a 7-year period, 91 patients with tropical pancreatitis underwent operation for intractable pain. Univariate and multivariate analyses were performed to identify factors correlating with mortality, major complications, poor pain relief and associated malignancy. Patients with benign disease (group 1, n = 72) had longer survival than those with superimposed malignancy (group 2, n = 19). Pain relief was better in group 1 (59 patients compared with none, P less than 0.01). Age above 40 years, short duration of symptoms, mass lesions on ultrasonography and main pancreatic duct obstruction on endoscopic retrograde pancreatography were associated with a high risk of cancer. After reoperation major complications (four of ten) or death (three of ten) occurred more commonly than after primary procedures (seven of 81, P = 0.019 and five of 81, P less than 0.05, respectively). Poor pain relief in group 1 patients was more common after incomplete clearance of main duct stones (four of 13 versus three of 53, P less than 0.01) and after short length ductotomy (three of eight versus four of 58, P less than 0.01). Tropical pancreatitis has a high association with pancreatic adenocarcinoma. Wide ductotomy, stone clearance and drainage gave good symptomatic results in patients with benign disease. Overall results were poor in patients with cancer. 相似文献
16.
Interferon-induced depressive illness in hep C patients responds to SSRI antidepressant treatments
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This paper examines the role of selective serotonin reuptake inhibitors (SSRIs) in the treatment of hepatitis-C virus (HCV) patients who have developed interferon-α induced depression. A 2-year data analysis of HCV psychiatric liaison clinic has been undertaken. The diagnosis, treatment, and progress of those patients who were treated with interferon-α (INF-α) are reported. 53 of the 78 patients enrolled at the HCV Clinic and treated with INF-α were referred for psychiatric consultation. Six patients developed major depressive illness following INF therapy. They were all treated with SSRIs and they made full recovery. This is a significant observation and is concordant with other studies. Its biochemical ramifications are presented. It is concluded that INF-induced depression is fully reversible. A hypothesis is proposed that SSRIs modulate the neuro-protective neurotoxic ratio by possibly inhibiting the indole-2,3-dioxygenase induction of the kynurenine pathway. 相似文献
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18.
Chenicheri Balakrishnan Venkata S Erella Christopher Vashi Ollie Jackson Shawn Vandemark 《CANADIAN JOURNAL OF PLASTIC SURGERY》2007,15(3):153-154
Self-inflicted burns represent a major social and medical problem for society. Differences have been demonstrated between patients who attempt suicide and those who deliberately harm themselves without any intention of killing themselves. These self-inflicted injuries may resemble injuries that are intentionally inflicted by others and may require investigation by protective services. Little is known about these specific pattern burn injuries in psychiatric patients. 相似文献
19.
Evaluation of active and passive transport processes in corneas extracted from preserved rabbit eyes
Soumyajit Majumdar Tushar Hingorani Ramesh Srirangam 《Journal of pharmaceutical sciences》2010,99(4):1921-1930
In vitro transcorneal permeability studies are an important screening tool in drug development. The objective of this research is to examine the feasibility of using corneas isolated from preserved rabbit eyes as a model for permeability evaluation. Eyes from male New Zealand White rabbits were used immediately or were stored overnight in phosphate-buffered saline (PBS) or Hanks balanced salt solution (HBSS) over wet ice. Integrity of isolated corneas was evaluated by measuring the TEER and by determining the permeability of paracellular and transcellular markers. Active transport was assessed by measuring transcorneal permeability of selected amino acids. Esterase activity was estimated using p-nitrophenyl assay. In all cases, corneas from freshly enucleated eyes were compared to those isolated from the day-old preserved eyes. Transcellular and paracellular passive diffusion was not affected by the storage medium and observed to be similar in the fresh and preserved eye models. However, amino acid transporters demonstrated lower functional activity in corneas excised from eyes preserved in PBS. Moreover, preserved eyes displayed almost 1.5-fold lower esterase activity in the corneal tissue. Thus, corneas isolated from day-old eyes, preserved in HBSS, closely mimics freshly excised rabbit corneas in terms of both active and passive transport characteristics but possesses slightly reduced enzymatic activity. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1921–1930, 2010 相似文献
20.
Kalpana Agarwal Anita Mukherjee Archana Sharma Ramesh Sharma Kuldip Raj Bhardwaj Soumitra Sen 《Environmental and molecular mutagenesis》1992,19(4):323-326
Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo. 相似文献