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1.
In the treatment of massive hematuria after renal biopsy, selective percutaneous vaso-occlusion with detachable balloons is an effective alternative to urological surgery, as demonstrated in the case of a 39-year-old man. A review of the literature, which records success rate of more than 90% in nonmalignant renal hemorrhage, confirms the therapeutic value of the various parenchyma-sparing embolization techniques.  相似文献   
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F A Lederle  K L Nichol  C M Parenti 《Chest》1989,95(5):1043-1047
Six of 106 older men with hemoptysis and a nonsuspicious chest roentgenogram who underwent fiberoptic bronchoscopy were found to have cancer. Four of the five bronchogenic carcinomas appeared to be surgically resectable. Cancer patients were significantly older, had smoked within the last five years, and had a significantly higher frequency of central abnormalities on chest roentgenogram. Six additional bronchogenic carcinomas were diagnosed at follow-up. Two of these were probably present but not detected at the time of bronchoscopy. We conclude that (1) hemoptysis with a nonsuspicious chest roentgenogram carries an appreciable risk of cancer in older men with substantial smoking histories, (2) these cancers are often resectable, (3) a chest roentgenogram in which the central lung fields are obscured in any way should not be considered negative in patients with hemoptysis, and (4) a negative bronchoscopic examination does not exclude the possibility of cancer in these patients.  相似文献   
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BACKGROUND: Little is known about the rate at which new abdominal aortic aneurysms (AAAs) develop or whether screening older men for AAA, if undertaken, should be limited to once in a lifetime or repeated at intervals. METHODS: A large population of veterans, aged 50 through 79 years, completed a questionnaire and underwent ultrasound screening for AAA. Of these, 5151 without AAA on the initial ultrasound (defined as infrarenal aortic diameter of 3.0 cm or larger) were selected randomly to be invited for a second ultrasound screening after an interval of 4 years. Local records and national databases were searched to identify deaths and AAA diagnoses made during the study interval in subjects who did not attend the rescreening. RESULTS: Of the 5151 subjects selected for a second screening, 598 (11.6%) had died (none due to AAA), and 20 (0.4%) had an interim diagnosis of AAA. A second screening was performed on 2622 (50.9%), of whom 58 (2.2%; 95% confidence interval, 1.6%-2.8%) had new AAA. Three new AAAs were 4.0 to 4.9 cm, 10 were 3.5 to 3.9 cm, and 45 were 3.0 to 3.4 cm. Independent predictors of new AAA at the second screening included current smoker (odds ratio, 3.09; 95% confidence, 1.74-5.50), coronary artery disease (odds ratio, 1.81; 95% confidence interval, 1.07-3.07), and, in a separate model using a composite variable, any atherosclerosis (odds ratio, 1.97; 95% confidence interval, 1.16-3.35). Adding the interim and rescreening diagnosis rates suggests a 4-year incidence rate of 2.6%. Rescreening only in subjects with infrarenal aortic diameter of 2.5 cm or greater on the initial ultrasound would have missed more than two thirds of the new AAAs. CONCLUSIONS: A second screening is of little practical value after 4 years, mainly because the AAAs detected are small. However, the incidence that we observed suggests that a second screening after longer intervals (ie, more than 8 years) may provide yields similar to those seen in initial screening and therefore warrants further study.  相似文献   
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Although abdominal aortic aneurysm (AAA) is 4 to 6 times more common in men than in women, more than a third of all AAA deaths occur in women. In several reports from the UK Small Aneurysm Trial group, the rupture rate for women was 3-4 times that seen in men. A joint council of several vascular societies responded to these observations with the recommendation that AAA should be repaired earlier in women, at 4.5 cm to 5.0 cm rather than the 5.5 cm established in randomized trials for men. However, this recommendation does not appear to reflect a full consideration of the evidence. For example, population-based studies have reported mortality following AAA repair to be 40-60% higher in women than in men. Also, in the UK Small Aneurysm Trial itself, there was no trend toward a benefit from early repair in women. The totality of evidence available at present provides no good reason to alter for women the 5.5 cm threshold for elective repair established for men by the small AAA trials.  相似文献   
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Riboflavin is an essential vitamin for cellular metabolism and is highly upregulated in metabolically active cells. Consequently, targeting the riboflavin carrier protein (RCP) may be a promising strategy for labeling cancer and activated endothelial cells. Therefore, Ultrasmall SuperParamagnetic Iron Oxide nanoparticles (USPIO) were adsorptively coated with the endogenous RCP ligand flavin mononucleotide (FMN), which renders them target-specific and fluorescent. The core diameter, surface morphology and surface coverage of the resulting FMN-coated USPIO (FLUSPIO) were evaluated using a variety of physico-chemical characterization techniques (TEM, DLS, MRI and fluorescence spectroscopy). The biocompatibility of FLUSPIO was confirmed using three different cell viability assays (Trypan blue staining, 7-AAD staining and TUNEL). In vitro evaluation of FLUSPIO using MRI and fluorescence microscopy demonstrated high labeling efficiency of cancer cells (PC-3, DU-145, LnCap) and activated endothelial cells (HUVEC). Competition experiments (using MRI and ICP-MS) with a 10- and 100-fold excess of free FMN confirmed RCP-specific uptake of the FLUSPIO by PC-3 cells and HUVEC. Hence, RCP-targeting via FMN may be an elegant way to render nanoparticles fluorescent and to increase the labeling efficacy of cancer and activated endothelial cells. This was shown for FLUSPIO, which due to their high T(2)-relaxivity, are favorably suited for MR cell tracking experiments and cancer detection in vivo.  相似文献   
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BACKGROUND: The vascular architecture of normal lymph nodes is composed of prominent centrally located blood vessels. In malignant nodes, this pattern is distorted because of tumor infiltration and neovascularization. OBJECTIVE: To determine whether EUS imaging of central intranodal blood vessels (CIV) can be used to differentiate benign from malignant subcarinal lymph nodes in lung cancer. DESIGN: CIV was defined as a > or =1-mm-diameter tubular structure, with well-defined walls and blood flow. The diagnostic accuracy of CIV was compared with other lymph-node features in a retrospective cohort of patients who underwent EUS for lung cancer evaluation. Findings were then prospectively validated in a similar cohort. SETTING: Minneapolis Veterans Affairs Medical Center. PATIENTS: Patients who underwent EUS for lung cancer diagnosis or staging at the VA Medical Center from March 2003 to March 2005. RESULTS: Of 67 patients included in the retrospective analysis, CIV was noted in 17 of 35 patients with benign nodes (49%), compared with 5 of 32 patients with malignant nodes (16%) (P = .002). In lymph nodes > or =1 cm, CIV was noted in 14 of 16 patients with benign nodes (88%), compared with 2 of 27 with malignant nodes (7%) (P < .001). Forty-five patients were included in the prospective validation cohort, and 16 had malignant lymph nodes. For malignant lymph-node metastasis, the absence of CIV had a sensitivity of 75%, a specificity of 97%, and an accuracy of 89%. The accuracy of CIV was superior to that of lymph-node shape; margin; and internal echo pattern, singly or in combination. CONCLUSIONS: The absence of a central intranodal blood vessel was a strong and independent predictor of malignancy in lymph nodes of patients with lung cancer and can be used to select lymph nodes for FNA.  相似文献   
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Objectives

To compare mesoscopic epi-fluorescence tomography (MEFT) and EPRI-illumination reflectance imaging (EPRI) for quantitative tumour size assessment in mice.

Methods

Tumour xenografts of green/red fluorescent protein (GFP/RFP)-expressing colon cancer cells were measured using MEFT, EPRI, ultrasound (US) and micro computed tomography (μCT) at day 14 post-injection (n?=?6). Results from MEFT and EPRI were correlated with each other and with US and μCT (reference methods). Tumour volumes were measured ex vivo by GFP and RFP fluorescence imaging on cryoslices and compared with the in vivo measurements.

Results

High correlation and congruency were observed between MEFT, US and μCT (MEFT/US: GFP: r 2?=?0.96; RFP: r 2?=?0.97, both P?r 2?=?0.93; RFP: r 2?=?0.90; both P?r 2?=?0.96; RFP: r 2?=?0.99; both P?P?r 2?=?0.95; RFP: r 2?=?0.94; both P?r 2?=?0.86; RFP: r 2?=?0.86; both P?Conclusions Fluorescence distribution reconstruction using MEFT affords highly accurate three-dimensional (3D) tumour volume data showing superior accuracy compared to EPRI. Thus, MEFT is a very suitable technique for quantitatively assessing fluorescence distribution in superficial tumours at high spatial resolution.

Key Points

? Mesoscopic epi-fluorescence tomography (MEFT) is an important new molecular imaging technique. ? MEFT allows accurate size determination of superficial tumours with high resolution. ? MEFT is a suitable technique for longitudinal assessment of tumour growth. ? MEFT allows 3D reconstruction and quantification of fluorescence distributions.  相似文献   
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