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991.
In the macaque, the posterior parietal cortex (PPC) integrates multimodal sensory information for planning and coordinating complex movements. In particular, the areas around the intraparietal sulcus (IPS) serve as an interface between the sensory and motor systems to allow for coordinated movements in space. Because recent imaging studies suggest a comparable functional and anatomical organization of human and monkey IPS, we hypothesized that in humans, as in macaques, the medial intraparietal cortex (area MIP) subserves visuomotor transformations. To test this hypothesis, changes of neural activity were measured using functional magnetic resonance imaging (fMRI) while healthy subjects performed a joystick paradigm similar to the ones previously employed in macaques for studying area MIP. As hypothesized, visuomotor coordinate transformation subserving goal-directed hand movements activated superior parietal cortex with the local maximum of increased neural activity lying in the medial wall of IPS. Compared to the respective visuomotor control conditions, goal-directed hand movements under predominantly proprioceptive control activated a more anterior part of medial IPS, whereas posterior medial IPS was more responsive to visually guided hand movements. Contrasting the two coordinate transformation conditions, changing the modality of movement guidance (visual/proprioceptive) did not significantly alter the BOLD signal within IPS but demonstrated differential recruitment of modality specific areas such as V5/MT and sensorimotor cortex/area 5, respectively. The data suggest that the human medial intraparietal cortex subserves visuomotor transformation processes to control goal-directed hand movements independently from the modality-specific processing of visual or proprioceptive information. 相似文献
992.
Mycobacterium marinum is an unusual atypical mycobacterium with low pathogenicity for humans in comparison with Mycobacterium tuberculosis. Among the non-tuberculous mycobacterial pathogens, Mycobacterium marinum is the most common pathogen to cause skin infections. Mycobacterium marinum infection causes chronic cutaneous lesions and in some cases deeper infections such as tenosynovitis, septic arthritis and rarely osteomyelitis. We report the case of a male patient presenting with tenosynovitis of the distal upper extremity secondary to Mycobacterium marinum infection. 相似文献
993.
BACKGROUND: A high risk of loosening has been reported in replacements performed because of avascular necrosis. PATIENTS AND METHODS: To study cementless total hip replacement (THR) in younger patients with avascular necrosis (AVN), we analyzed retrospectively the outcome in 129 cases: 46 Mittelmeier monobloc ceramic hips (22 cases with AVN), and 83 Zweymüller total hip systems (35 cases with AVN) clinically and radiographically. RESULTS: At follow-up, 17 Mittelmeier prostheses (10 AVN) and 4 Zweymüller prostheses (none with AVN) had been revised. The diagnosis did not affect the implant survival, but the Zweymüller THR fared better than the Mittelmeier system. The main reason for revision of Mittelmeier implants was aseptic loosening, 3 of 4 Zweymüller revisions were necessary due to polyethylene wear. This difference was confirmed by the radiographic evaluation of the still intact implants: Zweymüller THR showed better values for signs of osseointegration, radiolucent lines around the implants and migration, but more acetabular wear. None of these differences was affected by the AVN diagnosis. INTERPRETATION: We could not confirm that AVN is a risk factor in total hip replacement. 相似文献
994.
Rönkä R Krogerus L Leppänen E von Smitten K Leidenius M 《American journal of surgery》2004,187(4):491-496
BACKGROUND: The objective of the study was to evaluate the feasibility of radio-guided occult lesion localization (ROLL) in breast-conserving surgery for nonpalpable breast cancer. METHODS: Altogether 215 breast cancer patients were included in a prospective study. Ultrasonographically guided intratumoral injection of radioactive tracer was used for tumor localization in 64 patients with nonpalpable tumors, visible in breast ultrasonography (the ROLL group). Nonpalpable tumors, visible only in mammography, were localized with a help of a guidewire in 14 patients (the WGR group). The remaining 137 patients had palpable tumors. RESULTS: The proportion of specimens with close or involved margins (0 to 3 mm) was the same in the ROLL group (6%) and among cases with palpable tumors (5%). In addition the median length of the closest margin did not differ significantly between the groups. CONCLUSIONS: The results of ROLL for nonpalpable breast cancer are comparable with those for resection of palpable tumors. 相似文献
995.
Girardi LN Krieger KH Lee LY Mack CA Tortolani AJ Isom OW 《The Annals of thoracic surgery》2004,77(4):1309-14; discussion 1314
BACKGROUND: End-organ malperfusion is a dreaded complication of type A aortic dissections. Different strategies have been proposed to manage this complex cohort of patients. Ideal management includes the rapid restoration of organ perfusion while avoiding catastrophic rupture and tamponade. We present our experience with primary aortic repair as the optimal method of patient management. METHODS: From July 1997 until April 2003, 101 patients underwent dissection repair and were assessed for malperfusion of the central nervous system, renal, visceral or extremity circulation. Patients with coronary artery malperfusion were analyzed separately. Aortic repair was performed expeditiously utilizing femoral bypass, circulatory arrest, and antegrade perfusion after completion of the distal anastomosis. Persistent malperfusion led to additional procedures. In-hospital morbidity, end-organ salvage, and mortality were determined. Chi-square analysis defined variables contributing significantly to outcome. RESULTS: Twenty-three patients presented with malperfusion. The operative mortality for the entire cohort with malperfusion, 4.4% (n = 1), was not greater than those without it, 5.1% (n = 4). Five patients required additional procedures following aortic repair, a majority in patients with persistent extremity ischemia. All deficits resolved except for one patient with spinal ischemia and one with visceral ischemia. Visceral malperfusion was highly lethal with a mortality of 33% (n = 1). All other patients presenting with malperfusion survived to discharge. CONCLUSIONS: Patients with malperfusion in the setting of acute type A dissection should undergo immediate aortic reconstruction as the primary means of reestablishing end-organ perfusion. Early postoperative intervention for persistent deficits leads to a gratifyingly high rate of end-organ salvage. 相似文献
996.
Miller SP McQuillen PS Vigneron DB Glidden DV Barkovich AJ Ferriero DM Hamrick SE Azakie A Karl TR 《The Annals of thoracic surgery》2004,77(5):1698-1706
BACKGROUND: The objective was to determine the timing and mechanism of brain injury using preoperative and postoperative magnetic resonance imaging (MRI) and three-dimensional MR spectroscopic imaging (MRSI) in newborns with transposition of the great arteries (TGA) repaired with full-flow cardiopulmonary bypass. METHODS: Ten term newborns with TGA undergoing an arterial switch operation were studied with MRI, MRSI, and neurologic examination preoperatively and postoperatively at a median of 5 days (2 to 9 days) and 19 days (14 to 26 days) of age, respectively. Five term historical controls were studied at a median of 4 days (3 to 9 days). Lactate/choline (marker of cerebral oxidative metabolism) and N-acetylaspartate (NAA)/choline (marker of cerebral metabolism and density) were measured bilaterally from the basal ganglia, thalamus, and corticospinal tracts. RESULTS: Four TGA newborns had brain injury on the preoperative MRI. The only new lesion detected on the postoperative study was a focal white matter lesion in one newborn with a normal preoperative MRI. The MRSI of age-adjusted lactate/choline was quantitatively higher in newborns with TGA compared with those without heart disease (p < 0.0001), even in newborns without MRI evidence of preoperative brain injury. Lactate/choline decreased after surgery but remained elevated compared with controls. In newborns with TGA, those with preoperative brain injury on MRI had lower NAA/choline globally (p = 0.04) than those with normal preoperative MRI. Five newborns had a decline in NAA/choline from the preoperative to postoperative studies. CONCLUSIONS: Abnormal brain metabolism and injury was observed preoperatively in newborns with TGA. Brain injury is not solely related to the operative course. 相似文献
997.
998.
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1000.
Sotlar K Horny HP Simonitsch I Krokowski M Aichberger KJ Mayerhofer M Printz D Fritsch G Valent P 《The American journal of surgical pathology》2004,28(10):1319-1325
The diagnosis of systemic mastocytosis (SM) is based primarily on the histologic and immunohistochemical evaluation of a bone marrow trephine biopsy specimen. Although mast cell (MC) specific antigens like tryptase and chymase are detectable in routinely processed tissue, no immunohistochemical markers that can be used to discriminate between normal and neoplastic MCs are yet available. We have investigated the diagnostic value of an antibody against CD25 for the immunohistochemical detection of MCs in bone marrow sections in 73 patients with SM and 75 control cases (reactive marrow, n = 54; myelogenous neoplasms, n = 21) and correlated the results with the presence of c-kit mutations. While MCs in almost all patients with SM (72 of 73) expressed CD25, none of the control samples contained CD25-positive MCs. Irrespective of the SM subtype, most of neoplastic MCs expressed CD25. In 3 patients with advanced MC disease, pure populations of neoplastic MCs were obtained and found to express CD25 mRNA by RT-PCR analysis. In addition, all patients with CD25-positive MCs contained c-kit mutations, while all control cases exhibited wild type c-kit. CD25 therefore appears to be a reliable immunohistochemical marker for the discrimination of neoplastic from normal/reactive MCs, with potential as a diagnostic tool in SM. 相似文献