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81.
Davangere P Devanand Christian G Habeck Matthias H Tabert Nikolaos Scarmeas Gregory H Pelton James R Moeller Brett D Mensh Tyler Tarabula Ronald L Van Heertum Yaakov Stern 《Neuropsychopharmacology》2006,31(6):1327-1334
Temporoparietal and posterior cingulate metabolism deficits characterize patients with Alzheimer's disease (AD). A H(2)(15)O resting PET scan covariance pattern, derived by using multivariate techniques, was previously shown to discriminate 17 mild AD patients from 16 healthy controls. This AD covariance pattern revealed hypoperfusion in bilateral inferior parietal lobule and cingulate; and left middle frontal, inferior frontal, precentral, and supramarginal gyri. The AD pattern also revealed hyperperfusion in bilateral insula, lingual gyri, and cuneus; left fusiform and superior occipital gyri; and right parahippocampal gyrus and pulvinar. In an independent sample of 23 outpatients with mild cognitive impairment (MCI) followed at 6-month intervals, the AD pattern score was evaluated as a predictor of cognitive decline. In this MCI sample, an H2(15)O resting PET scan was carried out at baseline. Mean duration of follow-up was 48.8 (SD 15.5) months, during which time six of 23 MCI patients converted to AD. In generalized estimating equations (GEE) analyses, controlling for age, sex, education, and baseline neuropsychological scores, increased AD pattern score was associated with greater decline in each neuropsychological test score over time (Mini Mental State Exam, Selective Reminding Test delayed recall, Animal Naming, WAIS-R digit symbol; Ps<0.01-0.001). In summary, a resting PET covariance pattern previously reported to discriminate AD patients from control subjects was applied prospectively to an independent sample of MCI patients and found to predict cognitive decline. Independent replication in larger samples is needed before clinical application can be considered. 相似文献
82.
Daniela Klitscher Lars P. Müller Pol Rommens 《European journal of trauma and emergency surgery》2007,33(1):69-73
Abstract 10 embalmed cadaver forearms and wrists were dissected to determine the anatomical course of the superficial branch of the
radial nerve in the distal forearm. The superficial radial nerve bifurcated in two branches at a mean of 54,7 mm proximal
to the radial styloid. From the styloid process of the radius, the mean distance to the closest dorsal branch of the superficial
radial nerve was 3,5 mm and the mean distance to the closest volar branch was 9,8 mm. The mean distance between the closest
branch of the superficial radial nerve and Lister?s tubercle was 16,4 mm. The crossing point between the nerve and the cephalic
vein was located at a mean of 54,3 mm proximal to the styloid process. At the level of styloid process the mean distance between
the closest dorsal branch of the superficial radial nerve and the first dorsal compartment was 15,2 mm and between the closest
volar branch and the first dorsal compartment 4,4 mm. Detailed knowledge of anatomic characteristics of the superficial branch
of the radial nerve may help prevent injury during operations and treat traumatic lesions of the nerve. Because of great variations
in the course of the superficial radial nerve we could not define an absolute safe zone for surgical procedures on the distal
forearm. Iatrogenic lesions of the superficial radial nerve are described complications of percutaneous procedures. Therefore
open surgical approaches are recommended.
Daniela Klitscher and Lars Peter Müller contributed equally to this work. 相似文献
83.
84.
Benign schwannoma of the pancreas 总被引:2,自引:0,他引:2
Labile Togba Soumaoro Kenichi Teramoto Tohru Kawamura Noriaki Nakamura Takahiro Sanada Kenichi Sugihara Shigeki Arii 《Journal of gastrointestinal surgery》2005,9(2):288-290
Reported cases of intrapancreatic schwannomas have recently increased in the literature. However, none of these cases were
diagnosed clearly as schwannoma preoperatively. We herein describe the clinicopathologic findings of a solitary benign schwannoma
occurring in the head of the pancreas. Additionally, the differential diagnosis versus other cystic- and solid-appearing pancreatic
masses is briefly discussed. 相似文献
85.
Detection of the center of the hip joint in computer-assisted surgery: an evaluation study of the Surgetics algorithm. 总被引:4,自引:0,他引:4
Eric Stindel Daniel Gil Jean-Louis Briard Philippe Merloz Frédéric Dubrana Christian Lefevre 《Computer aided surgery》2005,10(3):133-139
OBJECTIVE: The aim of this paper is to assess the accuracy of an algorithm implemented by PRAXIM in the SURGETICS navigation station for detection of the hip center. This study will assess the robustness and accuracy of the algorithm in various clinical situations such as those involving non-sphericity of the femoral head, motion of the pelvis during hip center detection, and restricted range of motion. MATERIALS AND METHODS: The localization of the hip center, based on kinematics, relies on the recording of n successive positions of the femoral rigid body in the localizer reference system during a passive circumduction motion of the hip joint. Therefore, the shape of the clouds of points acquired may vary from one acquisition to the next. To allow a comprehensive study of the consequences of these variations for hip center detection, we developed a simulator to generate numerous clouds of points. Results given subsequently for each test are the values of the difference between the femoral mechanical axis computed with C(c), the computed hip center, and the same axis computed with C(o), the reference hip center. RESULTS: Test 1: Sensitivity to noise. The errors ranged from 3.33 E - 12 (SD 3.29E - 12) for a noise of 0 mm to 8.18E - 1 (SD - 7.05E - 1) for a noise of 15 mm. Test 2: Sensitivity to the shape of the acquisition motion. All trajectories gave an error < 1 degrees . Test 3: Sensitivity to restricted range of motion. No value > 1 degrees was found during this test. Test 4: Sensitivity to the distance between two points of the cloud. No value > 0.5 degrees was found during this test. Test 5: Sensitivity to the number of points included in the cloud. No value > 1 degrees was found during this test. CONCLUSIONS: The Surgetics algorithm is robust to noise, can compensate for pelvic motion, and can be used even in the case of restricted range of motion. 相似文献
86.
Hung J. Kim Torrance Jackson Konrad Noben–Trauth 《Journal of the Association for Research in Otolaryngology》2003,4(1):83-90
Genetic studies on spontaneous mouse mutants with hearing defects have provided important insights into the function of genes
expressed in inner ear hair cells. Here we report on our genetic analyses of the deaf mutants varitint-waddler (Va) and jerker
(Espnje). A high-resolution genetic map localizes VaJ to a 0.14 ± 0.08 cM region between D3Mit85 and D3Mit259 on distal chromosome
3. By comparative mapping, the human ortholog resides at 1p22.3 between markers D1S3449 and D1S2252. To study the effect of
different genetic backgrounds on the hearing phenotype, Espnje and VaJ were crossed to various inbred strains. Auditory-evoked
brainstem response tests on F2 progeny demonstrate that expression, inheritance, and penetrance of the hearing phenotype are
solely controlled by the mutant allele. To test for a genetic interaction between Espnje and Cdh23v, auditory function was
analyzed in double heterozygotes; no significant increases of thresholds of sound pressure levels were observed. The results
establish the framework for cloning the Va gene and provide valuable insights into the genetics of deafness mutations in the
mouse. 相似文献
87.
Abstract Surgical treatment of proximal humeral fractures still remains a challenge. This is primarily due to the fact that sufficient
implant fixation in humeral head fractures is often not achieved due to substantial bone tissue loss with increasing age.
In the last few years the locking plates and locking nails have been introduced into clinical practice with varying results.
The biomechanical studies have focused on locking plate osteosynthesis as well. The following paper focuses on bone quality,
biomechanical studies and biology of proper osteosynthesis and reviews the most recent literature. 相似文献
88.
89.
Uta Kraus-Tiefenbacher Lelia Bauer Antonella Scheda Carola Schoeber Joerg Schaefer Volker Steil Frederik Wenz 《BMC cancer》2007,7(1):178
Background
For patients suffering of recurrent breast cancer within the irradiated breast, generally mastectomy is recommended. The normal tissue tolerance does not permit a second full-dose course of radiotherapy to the entire breast after a second breast-conserving surgery (BCS). A novel option is to treat these patients with partial breast irradiation (PBI). This approach is based on the hypothesis that re-irradiation of a limited volume will be effective and result in an acceptable frequency of side effects. The following report presents a single center experience with intraoperative radiotherapy (IORT) during excision of recurrent breast cancer in the previously irradiated breast. 相似文献90.