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41.
Apparent diffusion coefficients of breast tumors: clinical application.   总被引:2,自引:0,他引:2  
PURPOSE: To evaluate the usefulness of apparent diffusion coefficient (ADC) for the differential diagnosis of breast tumors and to determine the relation between ADC and tumor cellularity. MATERIALS AND METHODS: One hundred and thirty-six female patients (age range, 17-83 years; average age, 51.7 years) with 140 histologically proven breast tumors underwent diffusion-weighted magnetic resonance (MR) imaging (DWI) using the spin-echo echo-planar technique, and the ADCs of the tumors were calculated using 3 different b values, 0, 500, and 1000 s/mm(2). The diagnoses consisted of fibroadenoma (FA, n=16), invasive ductal carcinoma, not otherwise specified (IDC, n=117), medullary carcinoma (ME, n=3) and mucinous carcinoma (MU, n=4). Tumor cellularity was calculated from surgical specimens. The ADCs of breast tumors and cellularity were compared between different histological types by analysis of variance and Scheffe's post hoc test. The correlation between tumor cellularity and ADC was analyzed by Pearson correlation test. RESULTS: Significant differences were observed in ADCs between FA and all types of cancers (P<0.05) and between MU and other types of cancers (P<0.01) and in cellularity between FA and cancers except MU (P<0.01) and between MU and other types of cancers (P<0.01). There was an inverse correlation between ADC and tumor cellularity (P<0.01, r(2)=0.451). CONCLUSIONS: The ADC may potentially help in differentiating benign and malignant breast tumors. Tumor ADC correlates inversely with tumor cellularity.  相似文献   
42.
Postoperative delirium is a serious and commonly encountered problem in the field of surgery. But in plastic surgery, this problem is rarely reported. We restrospectively examined the incidence of delirium using the 12-point Delirium Rating Scale in 364 inpatients treated over a 3-year period, whose ages ranged from 56 to 96 years. Surgery for malignant tumors was the most frequent type of surgery. The overall incidence of delirium was 1.4%; but when distributed by disease, patients with extramammary Paget’s disease showed the highest incidence. We then examined the records of patients with extramammary Paget’s disease or carcinoma treated in the ten previous years. The incidence in this group was 20.7%, and all of them were men. The average age of the male patients manifesting delirium was 79.8 years and that of those who did not develop delirium was 73.2 years. As many reports suggest, in our patients, precipitating factors such as physical restraints, bladder catheterization, and risk factors such as old age, seemed to have been strongly related to the occurrence of delirium. In conclusion, postoperative delirium is rarely observed in the field of dermatologic or plastic surgery. In our practice, the incidence of delirium was particularly high in patients with extramammary Paget’s disease, especially in elderly male patients. Close attention must be paid to this subset of patients to prevent delirium.  相似文献   
43.
Six patients with advanced prostatic cancer who had been treated by long-term administration of LH-RH agonistic preparations (Buserelin or Leupron) were tested for their pituitary-testicular endocrine functions. Serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), prolactin (PRL), estradiol (E2) and dihydrotestosterone (DHT) were measured consecutively. In all medically castrated patients, serum levels of LH, FSH, T, DHT and E2 were suppressed and particularly serum T levels were below the castration level of 1.0 ng/ml. On the other hand, serum PRL levels were unchanged after the long-term treatment with the agonists. Serum LH and FSH levels failed to respond to LH-RH stimulation after the treatment, whereas serum T responded to stimulation by human chorionic gonadotropin (hCG) to various degrees. It was remarkable that, in 4 out of 6 medically castrated patients treated up to more than 3 years, serum T response levels above 1.0 ng/ml were noted. It is suggested that testicular endocrine function to secrete T and DHT in patients under treatment with long-term LH-RH agonist administration are still preserved in response to hCG stimulation.  相似文献   
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The cortical blood flow adjacent to arteriovenous malformations was monitored in six patients before, during, and after excision of arteriovenous malformations using a thermal diffusion probe. In a large arteriovenous malformation, a progressive increase in cortical blood flow up to two times the preexcision value was noted with occlusion of the feeding arteries. Lowering arterial pressure to keep normal cortical blood flow during and after operation resulted in minimum brain edema and an excellent result. Direct measurement of cortical blood flow is of value in determining the precise level of hypotension to prevent brain edema and ischemia that may occur with excision of a large arteriovenous malformation.  相似文献   
46.
PURPOSE: Interleukin (IL)-1alpha and IL-6 levels in the cornea are greatly elevated during the early stages after an alkali burn in mice. The authors investigated the effect of synthetic inhibitor of matrix metalloproteinase (SIMP) on the expression of inflammatory cytokines in alkali-burned murine corneas and evaluated the clinical appearance of the eyes. METHODS: After 0.5N NaOH-alkali burns to 400 corneas of ICR mice, 200 received 400 microg/ml of SIMP topically 4 times a day while 200 corneas were similarly treated with vehicle only. At days 4, 7 and 14 after injury, each cornea was assigned a clinical score for corneal opacity, corneal epithelial defect, hyphema and cataract. Extracts of injured corneas in each group were then assayed for cytokine production using ELISA systems for IL-1alpha, IL-1beta, IL-6 and tumor necrosis factor-alpha (TNF-alpha). RESULTS: The levels of IL-1alpha, IL-1beta and IL-6 were significantly lower in the SIMP-treated group than in the vehicle-treated group 7 days after the burn. However, levels of these cytokines were similar in the SIMP and non-SIMP groups at days 4 and 14. Levels of TNF-alpha did not differ between both groups at any postinjury time. In the SIMP-treated corneas, there was less opacification and hyphema formation and epithelial regeneration was faster. CONCLUSIONS: Topical application of SIMP in alkali-burned murine corneas reduced the expression of IL-1alpha, IL-1beta, and IL-6 and lessened the severity of the injury.  相似文献   
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48.
Oxygen-induced retinopathy (OIR) has been widely studied as an animal model of retinal neovascularization diseases. Evaluation using this model is mainly performed by counting cell nuclei above the internal limiting membrane in serial cross-sections or by scoring in flat-mounted retinas. Quantitative evaluation is important for accurate elucidation of pathological conditions and the drug evaluations. We therefore attempted quantification using new imaging software and high-resolution images taken with a high-resolution CCD camera. Neonatal mice were exposed to 75% oxygen from postnatal day 7 (P7) to P12, then returned to room air until P17. At each evaluation time, mice were perfused with fluorescein-dextran, and flat-mounted retinas were prepared. Total images of the retinal vasculature were collected and analyzed using the imaging software. P17 normal retinas showed increases in computerized total tube area, total tube length, number of segments, and number of branch points (versus P7 normal retinas). These increases coincided with the development of the retinal vasculature between P7 and P17. P17 OIR retinas similarly showed increases in those parameters, and the number of nodes (thick regions exceeding the maximum width of the vessel) and the node area (abnormality induced by OIR) were markedly increased (versus P17 normal retinas). Accordingly, this approach is considered most suitable for evaluating the number of nodes and node area in this model. Quantification using the present imaging software should be useful for evaluating physiological and pathological neovascularizations in this OIR model.  相似文献   
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50.
Clinical Significance of FLT3 in Leukemia   总被引:4,自引:0,他引:4  
  相似文献   
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