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991.
992.
Jackson  VP; Lex  AM; Smith  DJ 《Radiology》1988,168(2):421-423
Vigorous compression is required to minimize radiation dose and maximize image quality for screen-film mammography. Of 356 women who adequately completed a questionnaire following mammography, 171 (48%) reported mammography to be comfortable, 135 (38%) uncomfortable but tolerable, 39 (11%) very uncomfortable, and only 11 (3%) found the examination to be intolerable. Only 14 women (4%) indicated that they would not return for mammography at our facility in the future. Because of this high level of acceptance of compression by women, technologists and radiologists should not hesitate to use vigorous compression to optimize image quality and decrease radiation dose to the patient.  相似文献   
993.
We monitored urinary aluminium excretion in 60 renal allograftrecipients for the first 6 months following transplantation.Plasma and urinary aluminium values steadily decreased duringthe study period. Patients who suffered two or more bacterialinfections during this period excreted more urinary aluminiumthan those with only one or no infections. Twenty patients experienced a two-fold or greater sudden unexpectedincrease in urinary aluminium excretion; 14 of these patients(60 per cent) had evidence of infection (10 bacterial and fourviral), at this time. Both urinary aluminium and fractionalaluminium excretion were greater in the 10 patients with bacterialinfection than in the other 10 patients. Thus, patients who suffered bacterial infections had higherbase-line urinary aluminium excretion, suggesting a higher bodyburden of aluminium. In addition, bacterial sepsis was associatedwith aluminium release from tissue stores with an associatedincrease in urinary aluminium excretion. This implies that patientswith an increased body burden of aluminium are more prone tobacterial sepsis, and that aluminium excretion is increasedduring sepsis.  相似文献   
994.
995.
Summary: Mediators released by glomerular macrophages may stimulate glomerular visceral epithelial cells (GVEC) to produce cytokines, growth factors or extracellular matrix components. This study describes that human GVEC produce monocyte chemoattractant protein-1 (MCP-1), a monocyte-specific chemotactic factor, and the effects of interleukin-lα (IL-1α) and tumour necrosis factor-α (TNF-a) on the production of MCP-1 by GVEC.
We observed that the intensity of MCP-1 staining in GVEC is stronger in membranous nephropathy and glomerulosclerosis than in normal kidneys. Various cell lines of GVEC produced significant amounts of MCP-1, as assessed by inhibition radio-immunoassay. the presence of IL-1α and TNF-α during culture of GVEC enhanced the production of MCP-1 in a dose- and time-dependent manner. Glomerular visceral epithelial cells in culture express mRNA for MCP-1 and the expression is upregulated 2.0- and 1.4-fold in the presence of optimal concentration of IL-1α and TNF-α, respectively. De novo synthesis of MCP-1 is supported by the observation that MCP-1 production is fully inhibited by cydoheximide. Monocyte chemoattractant protein-1 isolated from GVEC supernatants exhibits a molecular size of 12 and 10 kDa as determined by gel filtration chromatography. Both sizes of MCP-1 is chemotactically active for monocytes.
This study shows increased MCP-1 production by cultured human GVEC after stimulation with the inflammatory cytokines IL-1α and TNF-α. the expression of MCP-1 in GVEC was found to be upregulated in membranous nephropathy and glomerulosclerosis. These findings suggest that MCP-1 may be involved in glomerular injury in these diseases. the possible role of MCP-1 in the pathogenesis of human glomerulonephritis is discussed.  相似文献   
996.
Summary— Cyclophosphamide pharmacokinetics were investigated following administration to patients with systemic necrotizing angiitis. Ten patients (eight women and two men) received cyclophosphamide as a 1-h-rate-constant intravenous infusion at doses ranging from 600 to 1200 mg. All patients received concomitant oral prednisone (1 mg/kg/d). Blood samples were collected at the end of drug infusion and 0.25, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24 h later. Serum cyclophosphamide concentrations were assayed by high pressure liquid chromatography. The peak serum cyclophosphamide levels ranged from 15.7 to 29.4 mg/L. The mean cyclophosphamide elimination half-life was 6.2 ± 1.3 h (mean ± SD). The mean apparent volume of distribution and mean total plasma clearance were, respectively, 0.75 ± 0.22 L/kg (mean ± SD) and 83 ± 22 mL/min (mean ± SD). These results obtained in systemic vasculitic diseases were consistent with those observed in other studies with cancer patients receiving comparable doses of cyclophosphamide.  相似文献   
997.
998.
Adrenal tissue characterization using MR imaging   总被引:3,自引:0,他引:3  
Using a superconducting magnet operating at 0.35 T, the authors investigated the adrenal tissue characterization potential of magnetic resonance (MR) in 28 patients with 33 adrenal masses. There were 13 adrenal adenomas (12 non-hyperfunctioning, one aldosteronoma), nine adrenal metastases, four pheochromocytomas, two neuroblastomas, two adrenal lymphomas, two myelolipomas, and one adrenal cortical carcinoma. Spin-echo pulse sequences were obtained at TR 0.5, 2.0 sec and TE 28, 56 msec. Both qualitative (visual assessment) and quantitative (absolute signal intensity, intensity ratios, T1, T2) data were used for tissue characterization. The results suggest that non-hyperfunctioning adrenal adenomas can be distinguished from non-adenomas using both qualitative and quantitative data: 16/19 non-adenomas were visually hyperintense compared with liver at TR 2.0 sec, TE 56 msec, while none of the non-hyperfunctioning adenomas was relatively hyperintense at any pulse sequence used. Of the quantitative data, the intensity ratios of adrenal lesion/liver at TR 0.5 sec, TE 56 msec were most useful in diagnosis: all adenomas had ratios less than 0.83, while 19/20 non-adenomas had ratios exceeding this value. It is concluded that MR has considerable promise in adrenal tissue characterization.  相似文献   
999.
Khan  O; Cosgrove  DO; Fried  AM; Savage  PE 《Radiology》1986,159(1):111-113
Ultrasound (US) was compared with surgical findings in 98 patients with carcinoma of the ovary undergoing follow-up laparotomy after chemotherapy. US had an overall accuracy of 94% in the pelvis, with only small and sheetlike lesions escaping detection. It was more sensitive than clinical examination. Overall accuracy for the liver was 91% with very few false-positive results. For the peritoneal cavity in general, however, accuracy was low, with even large masses escaping detection. Ascites is reliably detected (accuracy of 97%) but is a poor indicator of peritoneal involvement. US is a useful noninvasive complement to laparoscopy in the follow-up of patients with carcinoma of the ovary.  相似文献   
1000.
Summary. Thirty-five single rooted teeth were biomechanically instrumented with salaine, following' which they were subjected to different methods of irrigation. Four groups of teeth were irrigatied using and Endomate unit with NaOCl in combination with H2O2, or EDTA, or glutaraldehde or saline.
Two groups were irrigated with 5 per cent NaOCl in combination with ultrasound; one of them was further irrigated with 3 per cent H2O2 using the Endomate system.
The control group was irrigated with NaOCl and H2O2 using the conventional technique. The prepared root canals were examined for the presence of smear layer under SEM.
All groups irrigated with the ultrasonic technique and the group irrigated with the endomate system using EDTA solution showed significantly cleaner surfaces; the smear layer was also greatly reduced.  相似文献   
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