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891.
Knox Joanna; Cordo Paul; Skoss Rachel; Durrant Shane; Hodges Paul 《Canadian Metallurgical Quarterly》2006,120(6):1211
Acuity for elbow joint position sense (JPS) is reduced when head position is modified. Movement of the head is associated with biomechanical changes in the neck and shoulder musculoskeletal system, which may explain changes in elbow JPS. The present study aimed to determine whether elbow JPS is also influenced by illusory changes in head position. Simultaneous vibration of sternocleidomastoid (SCM) and the contralateral splenius was applied to 14 healthy adult human subjects. Muscle vibration or passive head rotation was introduced between presentation and reproduction of a target elbow position. Ten out of 14 subjects reported illusions consistent with lengthening of the vibrated muscles. In these 10 subjects, absolute error for elbow JPS increased with left SCM/right splenius vibration but not with right SCM/left splenius vibration. Absolute error also increased with right rotation, with a trend for increased error with left rotation. These results demonstrated that both actual and illusory changes in head position are associated with diminished acuity for elbow JPS, suggesting that the influence of head position on upper limb JPS depends, at least partially, on perceived head position. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
892.
DR Nyholt RA Lea PJ Goadsby PJ Brimage LR Griffiths 《Canadian Metallurgical Quarterly》1998,50(5):1428-1432
Migraine is a frequent familial disorder that, in common with most multifactorial disorders, has an unknown etiology. The authors identified several families with multiple individuals affected by typical migraine using a single set of diagnostic criteria and studied these families for cosegregation between the disorder and markers on chromosome 19, the location of a mutation that causes a rare form of familial hemiplegic migraine (FHM). One large tested family showed both cosegregation and significant allele sharing for markers situated within or adjacent to the FHM locus. Multipoint GENEHUNTER results indicated significant excess allele sharing across a 12.6-cM region containing the FHM Ca2+ channel gene, CACNL1A4 (maximum nonparametric linkage Z score = 6.64, p = 0.0026), with a maximum parametric lod score of 1.92 obtained for a (CAG)n triplet repeat polymorphism situated in exon 47 of this gene. The CAG expansion did not, however, appear to be the cause of migraine in this pedigree. Other tested families showed neither cosegregation nor excess allele sharing to chromosome 19 markers. HOMOG analysis indicated heterogeneity, generating a maximum HLOD score of 3.6. It was concluded that Chr19 mutations either in the CACNL1A4 gene or a closely linked gene are implicated in some pedigrees with familial typical migraine, and that the disorder is genetically heterogeneous. 相似文献
893.
DE Craven RA Duncan JR Stram CJ O''Hara KA Steger K Jhamb LR Hirschhorn 《Canadian Metallurgical Quarterly》1998,128(6):455-459
Authors have presented results of vibratory stimulation in 20 anejaculatory spinal cord injury men. In 17 of 20 patients who had not ejaculated since their injuries, application of a vibrator to the penis caused ejaculation. Three of them had retrograde ejaculation. All patients with upper thoracic lesions received nifedipin. Side effects of vibratory stimulation were not reported. Semen can be used for assisted reproductive techniques. 相似文献
894.
LH Schwartz LR LaTrenta E Bonaccio WK Kelly HI Scher DM Panicek 《Canadian Metallurgical Quarterly》1998,208(3):735-738
BACKGROUND: Increased activity of the renin-angiotensin system has been implicated in decreased long-term survival of renal allografts. Recent studies suggest that a deletion variant of the angiotensin-converting enzyme, associated with increased humoral and tissue activity of this enzyme, may be a risk factor for the development of diabetic nephropathy and the progression of IgA nephropathy. The present study was conducted to determine whether the deletion variant of the angiotensin-converting-enzyme gene influences the long-term outcome in renal-transplant recipients. METHODS: We examined the relationship between recipient angiotensin-converting-enzyme genotype and clinical outcome in patients with a surviving allograft of at least 10 years (median survival 156 months, n= 86). Patients with an allograft survival of less than 3 years served as controls (median survival 10.4 months, n=87). RESULTS: Genotype distribution in long-term renal allograft survivors (II, 18; ID, 41; DD, 27; qD, 0.55) was similar to that in the control group (II, 12; ID, 53; DD, 22; qD, 0.56), and there were no significant differences between the genotypic groups in either cases or controls. Long-term survivors were more often female (58 vs 38%) and less often hypertensive (67 vs 77%). Both recipient and donor age were markedly lower in the long-term survivor group, whereas number of HLA mismatches and cold ischaemia time were comparable between cases and controls. CONCLUSIONS: This study does not support the hypothesis that the angiotensin-converting-enzyme insertion/deletion polymorphism is an important determinant of long-term transplant survival in Caucasian patients undergoing renal transplantation. 相似文献
895.
896.
J Holford SY Sharp BA Murrer M Abrams LR Kelland 《Canadian Metallurgical Quarterly》1998,77(3):366-373
BACKGROUND: Oral indomethacin causes villous shortening, microvascular damage, and distortion, which might induce mucosal ischaemia and necrosis. AIMS: In order to determine the early events in indomethacin induced jejunal injury we examined the temporal relations between morphological damage and changes in villous blood flow following indomethacin. METHODS: In anaesthetised rats, mid jejunal villi were exteriorised in a chamber and observed by fluorescence microscopy. Blood flow in surface capillaries was calculated from velocities and diameters. Indomethacin was applied by both luminal and intravenous routes for 90 minutes, after which the animal was perfusion fixed and the villi were processed for histological examination. Control animals received intravenous or luminal bicarbonate (1.25%). RESULTS: Blood flow slowed in individual villi at 20 minutes, and progressed to complete stasis (in another group) by 45 minutes. Histological examination at 20 minutes revealed microvascular distortion, but no villous shortening; crypt depth:villous height ratios were 0.356 (0.02) in test and 0.386 (0.01) in surrounding villi (p > 0.05). At stasis, the villi under study showed epithelial clumping and were shortened: crypt depth:villous height ratios were 0.92 (0.2) in test and 0.42 (0.06) in surrounding villi (p < 0.02). Vehicle alone had no effect on either blood flow or histology. CONCLUSIONS: Focal slowing of villous blood flow and microvascular distortion precede villus shortening and epithelial disruption, and indicate that damage to surface microvasculature is an early event in indomethacin induced mucosal injury in this model. 相似文献
897.
898.
A Santhosh LR Lakshmi P Arun KV Deepadevi KG Nair V Manojkumar PA Kurup 《Canadian Metallurgical Quarterly》1998,35(4):236-240
The Institute of Diagnostic Radiology at the Heinrich-Heine-University Duesseldorf has recently defined and implemented more than thirty organizational changes as a result of a quality control project. The aim was to improve quality and efficiency of the Radiology service. The project was carried out in cooperation with an external consulting firm. To date the positive impact of this project on our work has been so profound that we would like to communicate some of the results in form of this report. During the first phase of the project quality circles were formed to define the various quality criteria and aims of a good service. Today these represent the core of a new quality policy for the Institute. In a second phase all members of staff cooperatively developed precise plans of action for implementation of the necessary changes. Main achievements are the reduction of organizational and communicational deficits obstructing the work process, enhancement of interaction between junior and senior medical staff, upgrading of the role and field of action of the radiography staff and last but not least improvements of cooperation between secretarial and medical staff. 相似文献
899.
Recent studies using synthetic altered peptide ligands (Analogues) have led to the fine dissection of TCR-mediated T cell functions elicited by Ag recognition. Certain Analogues behave as full agonists of the antigenic peptide while others are partial agonists in that they only trigger selected T cell functions. Additionally, peptide Analogues can behave as antagonists by inhibiting functions of T cell clones when coincubated with the wild-type peptide. In fetal thymic organ cultures, synthetic altered peptide ligands can impact T cell repertoire selection. However, the influence of naturally occurring peptide Analogues on T cell immunity in vivo remains hypothetical. We previously reported that, in B10.A mice, immunogenicity and tolerogenicity of the self-MHC class I peptide, Ld 61-80, were influenced by the presentation of a cross-reactive self-peptide, Kk 61-80. Here, we show that Kk 61-80 self-peptide represents a partial agonist of Ld 61-80 in that it induced the proliferation but not the lymphokine production of Ld 61-80-primed T cells. Next, we showed that presentation of Kk 61-80 Analogue peptide mediated T cell tolerance toward Ld 61-80 self-peptide. Alternatively, when Ld protein represented an alloantigen displayed on transplanted cells, immunization with Kk 61-80 Analogue sensitized recipient mice to Ld 61-80 peptide, thus inducing potent immune responses to donor cells. These results show that the presentation of natural Analogue peptides may represent an essential component of T cell responses involved in autoimmunity and transplant rejection. 相似文献
900.
F Bénard D Sterman RJ Smith LR Kaiser SM Albelda A Alavi 《Canadian Metallurgical Quarterly》1998,114(3):713-722
BACKGROUND: The diagnosis of malignant mesothelioma is a challenging medical problem. CT often cannot differentiate between benign diffuse pleural thickening and malignant mesothelioma, while thoracentesis and CT-guided biopsies are insensitive. We have assessed the value of positron emission tomography (PET) with 2-fluoro-2-deoxy-D-glucose (FDG) in the evaluation of malignant mesothelioma. METHODS: Twenty-eight consecutive patients referred for the evaluation of suspected malignant mesothelioma were evaluated by FDG-PET imaging. Measured attenuation correction was performed in 26 of 28 cases for quantitation with the standardized uptake value (SUV) method. The results of PET imaging were compared with those of video-assisted thoracoscopy or surgical biopsies. RESULTS: Surgical biopsy specimens confirmed the presence of malignant disease in 24 patients and demonstrated benign processes in the remaining four. The uptake of FDG was significantly higher in malignant than in benign lesions (SUV=4.9+/-2.9 and SUV=1.4+/-0.6, respectively; p<0.0001). With a SUV cutoff of 2.0 to differentiate between malignant and benign disease, a sensitivity of 91% and a specificity of 100% could be achieved, although the activity in some epithelial mesotheliomas tended to be close to this threshold. FDG-PET images provided excellent delineation of the active tumor sites. Hypermetabolic lymph node involvement was noted on FDG-PET images in 12 patients, 9 of which appeared normal on CT scans. Histologic examination in six patients confirmed malignant nodal disease in five cases and indicated granulomatous lymphadenitis in one. CONCLUSION: In this highly selected population, FDG-PET imaging was a sensitive method to identify malignant mesothelioma and determine the extent of the disease process. 相似文献