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151.
The fine-needle aspiration (FNA) cytology of two cases of granulocytic sarcoma involving the breast is reported along with the FNA cytology of one case of myeloid metaplasia (extramedullary hematopoiesis) involving an axillary lymph node. Two patients had known myeloproliferative disorders, while granulocytic sarcoma of the breast was the initial presentation of an unsuspected acute granulocytic leukemia in the other patient. Diff-Quik-stained preparations aided in the diagnosis of all three cases. Immunoperoxidase stains for factor VIII-related antigen helped confirm the megakaryocytic differentiation of the cells in the FNA cytology of myeloid metaplasia. Electron microscopic (EM) examination performed on the aspirated material also showed megakaryocytic differentiation of the bizarre cells. FNA cytology can make a specific diagnosis of granulocytic sarcoma and myeloid metaplasia. The workup of these unusual extramedullary myeloproliferative masses was aided when immunocytochemistry and EM were performed on the aspirated material.  相似文献   
152.
We describe a novel method of reconstructing images of an anisotropic conductivity tensor distribution inside an electrically conducting subject in magnetic resonance electrical impedance tomography (MREIT). MREIT is a recent medical imaging technique combining electrical impedance tomography (EIT) and magnetic resonance imaging (MRI) to produce conductivity images with improved spatial resolution and accuracy. In MREIT, we inject electrical current into the subject through surface electrodes and measure the z-component Bz of the induced magnetic flux density using an MRI scanner. Here, we assume that z is the direction of the main magnetic field of the MRI scanner. Considering the fact that most biological tissues are known to have anisotropic conductivity values, the primary goal of MREIT should be the imaging of an anisotropic conductivity tensor distribution. However, up to now, all MREIT techniques have assumed an isotropic conductivity distribution in the image reconstruction problem to simplify the underlying mathematical theory. In this paper, we firstly formulate a new image reconstruction method of an anisotropic conductivity tensor distribution. We use the relationship between multiple injection currents and the corresponding induced Bz data. Simulation results show that the algorithm can successfully reconstruct images of anisotropic conductivity tensor distributions. While the results show the feasibility of the method, they also suggest a more careful design of data collection methods and data processing techniques compared with isotropic conductivity imaging.  相似文献   
153.
A "pseudo-pseudo" aneurysm of the left ventricle due to mid-ventricular obstruction from asymmetric septal hypertrophy is presented. A case of mid-ventricular hypertrophic obstructive cardiomyopathy (MVHOCM) was evaluated by means of echocardiography, angiocardiography, gated cardiac blood pool scanning, and a TI-201 myocardial scan. The gated cardiac blood pool scan appearance of MVHOCM is similar to pseudoaneurysm of the left ventricle. TI-201 myocardial imaging, however, was able to distinguish between MVHOCM and pseudoaneurysm of the left ventricle.  相似文献   
154.
Two experiments were performed to determine if bilateral parasagittal hypothalamic knife-cuts (KCs), which produce long-term overeating and obesity, after biochemical indices of brown adipose tissue (BAT) reactivity to thermogenic stimuli. In the first study, responses to environmental cold were tested. Four weeks after surgery, KC rats had gained 4-5 times more weight than controls and were obese (increased Lee Obesity Index and weight of gonadal white fat). Before being sacrificed, groups of KC and control rats were exposed to 4 degrees C for 21 hr or remained at 28 degrees C. Interscapular BAT weighed 300% more in KC rats, due largely to increased white fat content. Functional indices of BAT thermogenic capacity (protein content, DNA content, cytochrome oxidase activity and mitochondrial guanosine diphosphate (GDP) binding) were normal at 28 degrees C. Exposure to 4 degrees C produced greatly enhanced responses but these were equivalent for both groups. This suggested an intact capacity for non-shivering thermogenesis in obese KC rats. In the second study, the same BAT responses were examined in other rats fed a palatable "cafeteria" diet (CAFE). One week after surgery, KC and control rats were subdivided into groups that received chow alone or chow plus four different palatable foods daily. Before sacrificing 4-5 weeks later, KC rats had gained 3-4 times more weight than controls and were obese. Interscapular BAT weighed 200-300% more in KC rats. CAFE feeding produced larger increments in all variables for KC vs. control rats. Most importantly, GDP binding was reduced in both KC groups, and significantly more so after CAFE feeding.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
155.
Early detection of an inflammatory process involving bone and joints is very important in children with extremity pain. We reviewed the efficacy and pitfalls of three-phase bone scans in 100 consecutive children with acute extremity pain. Sixty-one of the subjects showed abnormalities on bone scans. The sensitivity and specificity of three-phase bone scans for acute osteomyelitis were 84% and 97%, respectively. Sensitivity and specificity for both acute septic joint and cellulitis were 93% and 100%, respectively. Pitfalls in interpretation of three-phase bone scans include simulation of infection by fracture and obscuration of osteomyelitis by septic arthritis, prior antibiotic treatment, and the occasional "cold" defect due to ischemia.  相似文献   
156.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
157.
From 1962 to 1983, 117 patients between the ages of 16 and 72 years (mean, 25 years) underwent total correction of tetralogy of Fallot. All patients were operated on because of recent deterioration. Eighty (68%) had had previous surgical palliation. Complications occurred in 38 cases (32%) before total correction and were more frequent in older patients. The hospital mortality was 7.8% and was highest in older patients and those with a previous Potts shunt. Fifty-nine patients were followed up for as long as 23 years (mean, 9.2 years) after total correction. The probability of survival at 5, 10, and 15 years after total correction was 96%, 96%, and 84%, respectively. The actuarial freedom from any significant cardiovascular event at 5, 10, and 15 years was 84%, 73%, and 50%, respectively. Reoperation was required in ten cases (17%), in which there was one operative death. Late death occurred in four cases (6.8%). Left ventricular dysfunction was documented in ten patients (17%), three of whom had mural thrombi and two of whom had cerebrovascular accidents. A significant rhythm disorder was present in 13 patients. Fifty-four of the 55 surviving patients were in New York Heart Association (NYHA) functional class I or II at last follow-up. We conclude that 1) total correction of tetralogy of Fallot in adults is associated with a low operative mortality, similar to that in children, and offers symptomatic relief in most cases; 2) the long-term survival is excellent, but late sequelae become more frequent at late follow-up; 3) "corrective" reoperation can be done with a low risk; and 4) most of the survivors are in NYHA functional class I or II and lead normal, productive lives.  相似文献   
158.
A fibronectin substrate will significantly enhance the strength of endothelial cell attachment on grafts constructed of polyester elastomer (PE) and polytetrafluoroethylene (e-PTFE). This experiment was undertaken to determine the short-termin vivo stability of endothellum on these fibronectin coated surfaces. Eight mongrel dogs underwent bilateral carotid artery replacement with both graft materlals. All grafts were inoculated with 2,000 cells/mm2 using cultured autogenous venous endothelium labelled with Indium-111-oxine. The Indium-111 label in the grafts was measured immediately prior to implantation, after 1 hour ofin vivo perfusion, and at explantation after 24 hours. The percentage of inoculated cells attached to the grafts before perfusion was simillar for both materials, 93.3±3.0% versus 92.2±7.2%, for PE and e-PTFE respectively. All grafts were patent at one hour after implantation. PE grafts were found to have 93.8±3.9 % of the attached cells present at one hour while e-PTFE grafts had only 54.5 ± 10.8 % remaining, p<.001. After 24 hours, 5/8 (62.5%) e-PTFE grafts and 2/8 (25.0 %) PE grafts remained patent, p=.13. Of the patent grafts however, endothelial cell retention was still superior on the PE grafts with 78.0±0.6% of the attached cells remaining compared to only 24.5±6.1% on e-PTFE, p<.001. Occluded PE grafts had fewer cells remaining at 24 hours than patent ones, 78.0±0.6% versus 31.1±32.8%, respectively, p=.13. Histologically, patent PE grafts demonstrated nearly confluent endothelial monolayers while e-PTFE had patches of endothelial cells surrounded by, a platelet-fibrin carpet. We conclude that short-term patency appears to be determined by the extent of endothelial retention on PE but not e-PTFE.  相似文献   
159.
The 13C-triolein breath test is a method giving evidence of extent and rate of fatty acid oxidation in newborn infants on parenteral nutrition. The test has the special advantage of being non-invasive. Triolein labeled with the stable carbon isotope 13C and emulsified in soybean-oil is used as a tracer. 10 mg of 13C triolein per kg body weight are administered intravenously. The 13CO2 resulting from the fatty acid oxidation is analysed in expired breath by ratio-mass-spectrometry. The calculated 13C elimination is representative of the rate of fatty acid oxidation during the examination period. First studies on 15 premature infants have shown that an average of 27.0 +/- 1.8% of the dose administered is oxidized within 4 h. The present results suggest that the oxidation rate may be related to the maturity of the prematurely born infants.  相似文献   
160.
International Urology and Nephrology - A systemic inflammation response index (SIRI) has been recently introduced as a tool for the assessment of the prognosis of several critical medical...  相似文献   
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