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51.
BACKGROUND: Subjective memory complaints in subjects with mild cognitive impairment may represent a genuine decline in episodic memory. This paper evaluates the neuropsychological correlates of the semantic fluency test in subjects with questionable dementia (QD). METHODS: A total of 331 Chinese subjects (118 normal controls, NC, 150 with QD and 63 with mild Alzheimer's disease, AD) were assessed with the Category Verbal Fluency Test (CVFT), the AD Assessment Scale-cognitive subscale (ADAS-Cog), and digit and verbal span tests. CVFT performance was evaluated in each Clinical Dementia Rating (CDR) group. The total number of exemplars, the subcategory and the category size generated were evaluated. Neuropsychological correlates of CVFT scores were computed. RESULTS: Significant differences in CVFT performance were found between the different CDR groups. The subjects with QD had intermediate scores compared to the NC and AD subjects (1-way ANOVA, p < 0.001, post-hoc Bonferroni comparisons). In NC the CVFT scores were significantly associated with ADAS-Cog total, and immediate and delayed recall scores (partial correlations controlled for age and education, p < 0.005). In the QD group the CVFT scores were correlated with ADAS-Cog total, and immediate recall and object naming scores (partial correlation controlled for age and education, p < 0.005). Regression analysis revealed that age and delayed recall were significant predictors of CVFT performance in NCs. In the QD group, age, ADAS-Cog immediate recall and object naming scores predicted the CVFT performance. CONCLUSIONS: The CVFT was impaired in the subjects with QD. Apart from episodic memory, semantic memory deficits also occur early in AD. The different cognitive predictors of CVFT scores in the NC and QD groups suggest that the test is associated with specific psychological functions at different stages of cognitive impairment. 相似文献
52.
Scoliosis is a multifactorial three-dimensional (3D) spinal deformity with integral and directly related vertebral deviations
in the coronal, sagittal and horizontal planes. Current classification and diagnostic methods rely on two-dimensional (2D)
frontal and lateral X-ray images; no routine methods are available for the visualization and quantitative evaluation of deviations
in the horizontal plane. The EOS 2D/3D system presented here is a new, low-dose, orthopedic radiodiagnostic device based on
Nobel prize-winning X-ray detection technology with special software for 3D surface reconstruction capabilities that finally
led to a breakthrough in scoliosis diagnosis with high-quality, realistic 3D visualization and accurate quantitative parametric
analysis. A new concept introducing vertebra vectors and vertebra vector parametric calculations is introduced that furnishes
simplified visual and intelligible mathematical information facilitating interpretation of EOS 2D/3D data, especially with
regard to the horizontal plane top view images. The concept is demonstrated by a reported scoliotic case that was readily
characterized through information derived from vertebra vectors alone, supplemented with the current angulation measurement
methods in the coronal and sagittal planes and axial vertebral rotation measurements in the horizontal plane, with a calibrated
3D coordinate system suitable for inter-individual comparisons. The new concept of vertebra vectors may serve as a basis for
a truly 3D classification of scoliosis. 相似文献
53.
Tam VK Murphy K Parks WJ Raviele AA Vincent RN Strieper M Cuadrado AR 《The Annals of thoracic surgery》2001,71(5):1537-1540
BACKGROUND: Excessive pulmonary blood flow increases ventricular volume work in the face of inadequate systemic cardiac output, low diastolic blood pressure, and inadequate coronary perfusion. Using the smallest available 3-mm polytetrafluoroethylene shunts have been successful, although catastrophic shunt thrombosis has occasionally been observed. To avoid thrombosis with a smaller conduit, saphenous vein homografts (SVG) were used to construct the modified Blalock-Taussig (BT) shunts. METHODS: From January 1998 to April 1999, 25 patients weighing 3.1 kg (3.0 kg or less, n = 9), at a mean age of 8.9 days, underwent stage I Norwood using an SVG BT shunt. Common heart defects were aortic atresia (n = 8), mitral atresia and double-outlet right ventricle (n = 5), and unbalanced AVC (n = 5). Mean BT shunt size was 3.2 mm, with 12 patients having shunts that were 3 mm or smaller. RESULTS: Thirty-day hospital mortality was 8% (2 of 25). No shunt thrombosis was seen, despite banding the BT shunt in 3 patients. One patient had BT revision because of an anatomic issue not directly related to the shunt material. CONCLUSIONS: Excellent results may be achieved using SVG BT shunts in the Norwood operation. This conduit seems less likely to thrombose, both acutely and chronically, allowing the use of appropriately smaller-sized shunts in small neonates. 相似文献
54.
William P. Grant DPM Laurence G. Rubin DPM Guy R. Pupp DPM George Vito DPM Dwayne Jacobus DPM Erin A. Jerlin DPM Harry S. Tam DPM 《The Journal of foot and ankle surgery》2007,46(5):325-335
The purpose of this study was to assess 7 methods of fixation for a midtarsal osteotomy. Polyurethane foam models (N = 6) and cadaver specimens (N = 4-7) were used to examine the force generated by the different constructs of fixation. A midtarsal osteotomy was performed on each specimen in the test groups. The osteotomies were fixated either with 2 parallel 0.062-in Kirschner wires and 40-mm-long, 4-mm partially threaded, cancellous, cannulated titanium screws, an external ring fixator (frame), a frame with wires tensioned (tension), a frame with wires tensioned and compressed toward the osteotomy (tension and compression), a frame with tension, compression, and parallel Kirschner wires, or a frame with tension, compression, and two 4.0 cannulated parallel screws, respectively. Each model was fixated, and the force generated by the construct across the osteotomy was recorded via the use of pressure-sensitive film. Statistical analysis of the data in the polyurethane foam group determined that the use of frame with tension, compression, and two 4.0 parallel cannulated screws was statistically superior to 1) frame, 2) frame with tension, 3) 2 parallel Kirschner wires, 4) two 4.0 cannulated parallel screws, and 5) frame with tension and compression. A cadaver study determined that the frame with tension, compression, and 2 parallel Kirschner wires was statistically superior to 1) frame and 2) two parallel Kirschner wires. These findings suggest that there is a difference in the force generated by the type of fixation construct across a midtarsal osteotomy. 相似文献
55.
56.
X. L. Tang L. Qin A. W. Kwok T. Y. Zhu E. W. Kun V. W. Hung J. F. Griffith P. C. Leung E. K. Li L.-S. Tam 《Osteoporosis international》2013,24(6):1817-1826
Summary
Compared to controls, HR-pQCT at distal radius of SLE patients on chronic glucocorticoid (SLE/GC) revealed reduced bone area, vBMD, deteriorated microarchitecture, and unevenly distributed stresses limited to cortical bone. Despite similar trabecular quality, whole bone strength decreased in patients. These alterations may partly explain high fracture rates in SLE/GC.Introduction
To assess bone geometric, densitometric, microarchitectural, and biomechanical properties in patients with systemic lupus erythematosus (SLE) on long-term glucocorticoid (GC) (SLE/GC) as compared with healthy controls.Methods
A total of 180 female SLE patients and 180 healthy controls were in this cross-sectional study to assess areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) and microfinite element analysis (μFEA) was performed at distal radius.Results
In addition to significantly lower aBMD at femoral neck, total hip and lumbar spine, cortical area, average volumetric BMD (vBMD) and cortical vBMD also significantly reduced by 5.3, 5.7, to 1.9 % in SLE patients, respectively. Deteriorations of cortical microarchitecture were pronounced in patients, with 6.3 % reduction in cortical thickness and 13.6 % higher in cortical porosity. Local stresses were more unevenly distributed through cortical bone in patients. SLE/GC patients had decreased whole bone stiffness, estimated failure load, and apparent modulus. Parameters related to trabecular bone density and microarchitecture were comparable between patients and controls.Conclusion
In SLE/GC patients, despite a reduction in bone area, vBMD and deteriorated microarchitecture and unevenly distributed stresses limited to the cortical compartment, whole bone strength decreased. HR-pQCT and μFEA were promising in elucidating the potential underlying pathophysiology of bone loss and propensity to fracture in SLE/GC and provide us additional information about alterations of bone quality which might better predict fracture risk beyond aBMD in SLE/GC. 相似文献57.
Estrera AL Miller CC Porat E Mohamed S Kincade R Huynh TT Safi HJ 《The Annals of thoracic surgery》2004,78(3):837-845
Background
The purpose of this study was to investigate the cause of ascending aorta and aortic arch reoperations and to identify determinants of early and late outcome.Methods
Between January 1991 and March 2003 we repaired aneurysms of the proximal aorta in 597 patients. Of these patients, 104 had reoperations for replacement of the ascending aorta, aortic root, or transverse aortic arch. Previous surgery was defined as any previous cardiac or proximal aortic repair. Median age was 60 years, and 29 of the patients (28%) were female. Indications for reoperation and replacement of the proximal aorta included acute type A dissection in 6 patients (5.8%), aneurysm with chronic dissection in 60 (57.7%), progression of aneurysm in 23 (22.1%), infection in 12 (1.5%), inflammatory disease in 2 (1.9%), and atheromatous disease in 1 (1.0%). Reoperations included aortic root replacement in 20 patients (19.2%), total arch replacement with elephant trunk in 28 (26.7%), ascending and proximal arch in 39 (37.5%), and ascending aorta in 27 (26.0%). The median interval between operations was 69 months. Retrograde cerebral perfusion was used in 80 (77%) cases.Results
Chronic dissection was the most common indicator for reoperation in our population, followed by progression of aneurysm and infection. Thirty-day and in-hospital mortality was 13.5% (14 of 104) and 15.4% (16 of 104), respectively. Chronic obstructive pulmonary disease, renal dysfunction, and increased pump time were risk factors for mortality. Median follow-up was 5.02 years. Eight patients died during that period. Estimated survival at 1, 5, and 10 years was 83%, 80%, and 62%, respectively. Freedom from second proximal reoperations was 97.1% (10 of 104). Freedom from subsequent distal thoracic aortic repair was 84.6% (8 of 104).Conclusions
Reoperations of the ascending aorta and aortic arch can be performed safely with good long-term results. Patients with previous proximal aortic dissection repair need long-term surveillance. Renal dysfunction and chronic obstructive pulmonary disease must be carefully considered before reoperations of the proximal aorta. 相似文献58.
Molecular cloning and nucleotide sequence of the alpha and beta subunits of allophycocyanin from the cyanelle genome of Cyanophora paradoxa. 总被引:13,自引:1,他引:13 下载免费PDF全文
59.
Wayne Hsu Ching-Shyang Chen Hung-Chia Lee Hung-Hua Liang Li-Jen Kuo Po-Li Wei Ka-Wai Tam 《World journal of surgery》2012,36(10):2311-2319
Background
Chronic groin pain after inguinal hernia repair, a serious problem, is caused by entrapment of the ilioinguinal nerve either by mesh or development of fibrosis. Division of the ilioinguinal nerve during hernioplasty has been found to reduce the incidence of chronic groin pain. However, the traditional approach favors preservation of the ilioinguinal nerve during open hernia repair.Methods
We conducted a systematic review and meta-analysis of randomized controlled trials that compared the outcomes of preservation versus division of the ilioinguinal nerve during open mesh repair of inguinal hernia. The primary outcome was the incidence of groin pain; secondary outcomes were numbness and sensory loss.Results
We reviewed six trials with 1,286 patients. We found no difference between the groups for the incidence of groin pain or numbness at 1, 6, and 12 months after open mesh inguinal repair. The incidence of sensory loss or change was significantly higher in the division group than in the preservation group at 6 months [risk ratio (RR) 1.25; 95?% confidence interval (CI) 1.02–1.53] and at 12 months (RR 1.55; 95?% CI 1.01–2.37) postoperatively. No significant differences between the groups were noted at any other points in time.Conclusions
Preservation of the ilioinguinal nerve during open mesh repair of inguinal hernia is associated with a decreased incidence of sensory loss at 6 and 12 months postoperatively compared with that of the division technique. No significant differences were found between the groups for chronic groin pain or numbness. 相似文献60.
Tracy Y. Zhu James F. Griffith Ling Qin Vivian W. Y. Hung Tsz-Ning Fong Anthony W. Kwok Ping-Chung Leung Edmund K. Li Lai-Shan Tam 《Calcified tissue international》2012,91(5):343-355
We assessed the relationship of bone density and microarchitecture between hand, peripheral, and axial skeletal sites using high-resolution peripheral quantitative computed tomography (HR-pQCT) and dual-energy X-ray absorptiometry (DXA) in patients with rheumatoid arthritis (RA) and which factors influence these parameters. This was a cross-sectional study of 100 female patients (53.4?±?9.3?years) with RA. HR-pQCT scans at distal radius and the second metacarpal head were performed to assess cortical and trabecular volumetric bone mineral density (vBMD) and microarchitecture. DXA scans at the hip, lumbar spine, and ultradistal radius were performed to assess areal BMD. There was significant correlation in vBMD and microarchitectural parameters between the second metacarpal head and distal radius (r?=?0.201?0.628). Areal BMD at the axial skeleton was moderately associated with vBMD at the peripheral sites (r?=?0.354–0.558). Factors related to disease severity/chronicity significantly correlated with vBMD and microarchitecture at the distal radius and the second metacarpal head. Factors related to disease activity were more likely to correlate with vBMD and microarchitecture at the second metacarpal head but not those at the distal radius. HR-pQCT is a promising technique that is capable of providing detailed quantitative assessment of disease-associated periarticular bone loss at both cortical and trabecular bone compartments in patients with RA. Future longitudinal studies will be needed to investigate whether assessment by HR-pQCT can be used as a marker of disease activity and a predictor of disease progression in RA. 相似文献