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101.
During insertion of a central venous sheath an inferior vena cava stainless steel Greenfield filter was dislodged to the right brachiocephalic vein without a free end. Successful retrieval was achieved by using a combination of a guidewire and a snare. Percutaneous retrieval of this vena cava filter is feasible with minimal risk using this method.  相似文献   
102.
BACKGROUND: In 1989, skin-sparing mastectomy started at a number of breast centers in the United States because of an increasing demand for immediate reconstruction and a desire for better cosmetic outcomes. METHODS: To ensure the safety of this new approach, we have reviewed the personal series of a single surgeon using a standardized skin-sparing technique during 1989 to 2004. RESULTS: Skin-sparing mastectomy with immediate reconstruction was performed on 225 patients, and standard mastectomy was performed on 1,022 patients. The age distribution was 8 years younger on average in the reconstructed group. The average follow-up for each group was 49 months. The local recurrence for each group was 1.7% and 1.5% (P > .80). The regional recurrence was 3.8% and 3.9% (P > .80). The average time to local recurrence was similar in each group (33.1 and 32.6 months, P > .80). CONCLUSIONS: A skin-sparing mastectomy does not change the local, regional, or systemic risk to breast cancer patients.  相似文献   
103.
Neovascularization in acute venous thrombosis   总被引:1,自引:0,他引:1  
OBJECTIVE: The aim of this study was to describe the phenomenon of arteriovenous fistula (AVF) formation in venous thrombus. METHODS: Patients referred to the vascular laboratory for evaluation for deep venous thrombosis were included. Duplex ultrasound scanning was used to detect flow within the thrombus. The flow patterns and the resistivity index were obtained in the veins above/proximal and below/distal to the thrombus, in the adjacent arteries, and within the perivenous vessels. Patients with trauma, hemodialysis access, endovenous ablation, known AVF, or inflammatory conditions were excluded. RESULTS: There were 22 patients with AVF flow in thrombosed veins. Deep veins were involved in 15 cases and superficial veins in the remainder. Perivenous vessels feeding the AVF in the thrombus could be clearly identified in 16 patients (19 vein segments). In 21 of 22 patients, multiple flow channels were present throughout the involved thrombosed vein segment. These flow channels were isolated to a single vein segment. They measured <4 cm in length in 19 cases and were more extensive in the remaining three. Reflux within the vein segment was identified in 13 cases. Local symptoms that could be attributed to the arterialization of thrombosed veins occurred in four cases, and none of the patients manifested systemic symptoms. The flow within the thrombus had high end-diastolic velocities with a mean resistivity index of 0.48 (SD, 0.08), which is typical of a fistula flow pattern. The flow in the main arteries was unaffected. CONCLUSION: Neovessels were found with AVF flow in thrombi of superficial and deep veins. They had variable length and multiple flow channels, with inflow from perivenous arteries. The flow in the adjacent main arteries was not affected, and no systemic symptoms were detected. The exact etiology and natural history of this phenomenon are not known, and its clinical significance is unclear.  相似文献   
104.
The aim of this in vitro study was to evaluate the depth of effectiveness of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation on microorganism reduction. From human roots, dentin slices of 100 μm to 1,000 μm thickness were prepared. These specimens were sterilized and then inoculated with 1 μl of Enterococcus faecalis suspension. The backs of the specimens were then irradiated with Er,Cr:YSGG radiation at a pulse energy of 3.13 mJ, delivered at an incidence angle of 5° to the dentin slice surface. A control group was left without irradiation. The remaining bacteria were collected in 1 ml sterilized NaCl solution, serially diluted and seeded in Columbia-Agar plates. Despite the low pulse energy of 3.13 mJ, the Er,Cr:YSGG laser irradiation resulted in significant bacterial reduction up to a dentin thickness of 500 μm (P < 0.05). Scanning electron microscopy (SEM) micrographs of the contaminated and irradiated surfaces showed the absence of a smear layer and opened dentinal tubules.  相似文献   
105.
Regional correlation of PET and CT in senile dementia of the Alzheimer type   总被引:1,自引:0,他引:1  
Alzheimer disease is manifested by both widespread and regionally restricted brain changes, some of which have recently been identified in vivo with computed tomography (CT) and positron emission tomography (PET). This is a report of the regional correlation of CT and PET measurements in 19 carefully diagnosed subjects comprising 11 controls and eight patients with senile dementia of the Alzheimer type. Regional CT attenuation values did not discriminate between the two groups, but PET using 18F-2-deoxy-2-fluoro-D-glucose demonstrated significant regional reductions (range, 21%-28%) in glucose utilization in the Alzheimer group. PET measures were also more consistently related to cognitive decline. The correlation between CT structural measures and PET metabolic measures demonstrated consistent relations between widespread PET regions and CT changes in the thalamus, posterior limb of the internal capsule, and temporal lobes. However, CT changes in the frontal white matter, caudate nucleus, and anterior limb of the internal capsule were not related to any regional PET changes. These data support previous findings of temporal lobe involvement in Alzheimer disease and suggest the involvement of structures in the region of the third ventricle.  相似文献   
106.
107.
Grade progression and regression in recurrent urothelial cancer   总被引:3,自引:0,他引:3  
PURPOSE: Recurrent urothelial cancers are reported to have characteristics similar to those of the primary tumor, with 10% to 25% of low grade tumors recurring as high grade disease. We determined how often grade progression and regression occur and whether abnormalities in p53 protein expression in original tumors are preserved in recurrences. MATERIALS AND METHODS: Two groups of patients treated for recurrent stages Ta/T1 urothelial bladder cancers with at least 1 tumor-free examination between the index and recurrent tumors were reviewed. Group 1 included 115 patients in whom the first available tumor was compared with the last recurrence and group 2 included 42 in whom the initial tumor was compared with the first recurrence. Immunohistochemical analysis of p53 expression was performed on a subset of 34 tumor pairs. RESULTS: In group 1, 33 grade 3 tumors (45%) recurred as grade 1 or 2 tumors, while 9 of 82 grades 1 and 2 tumors (11%) recurred as grade 3 tumors. Five of 7 group 2 grade 3 tumors (71%) recurred as grade 1 or 2 disease, while 1 of 35 grades 1 and 2 tumors (3%) recurred as grade 3 disease. In the 34 pairs studied immunohistochemically 6 of 14 grade 3 tumors recurred at lower grades. Nuclear p53 over expression occurred in 21 index tumors (12 of 14 grade 3, 8 of 17 grade 2 and 1 of 3 grade 1) and in 9 recurrences (6 of 10 grade 3, 2 of 17 grade 2 and 1 of 7 grade 1). Only 7 of 21 p53 positive and 2 of 12 p53 negative index tumors were p53 positive on recurrence. CONCLUSIONS: While progression from low to high grade occurred in less than 15% of patients, grade regression was observed in almost 50%. The loss of p53 positivity in regressing tumors indicates that these recurrences are molecularly distinct from the corresponding initial tumor.  相似文献   
108.
Anaplastic thyroid cancer is a rare but nearly universally fatal tumor. Epidemiologic data suggest that many anaplastic thyroid carcinomas arise from transformation of preexisting or coexisting well-differentiated thyroid carcinomas. At the molecular level, the mutations responsible for the anaplastic transformation are incompletely understood, although the mutational events are thought to involve tumor suppressor genes. To examine transformation from a well-differentiated thyroid carcinoma to anaplastic carcinoma, we studied coexisting well-differentiated (Hürthle cell and papillary carcinoma) and anaplastic tumors with a molecular genotyping panel of tumor suppressor genes associated with thyroid neoplasia. The patterns of allelic loss in our results showed that the majority of cases have a core of conserved mutations in the two morphologically distinct areas and substantial increases in mutation rates in the anaplastic components.  相似文献   
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