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991.
PURPOSE: We report our experience of diagnosing and treating hepatic angiomyolipoma (HAML), a rare benign mesenchymal tumor. METHODS: We analyzed retrospectively the clinicopathologic, radiological, and operative data of 25 patients who underwent surgery for HAML at our institute between November 2001 and May 2006. RESULTS: Most patients (20/25) were asymptomatic and had normal liver function. Ultrasonography (US) showed a heterogeneous hyperechoic mass in 13 of 23 patients, precontrast computed tomography (CT) showed that all of 12 lesions scanned were hypodense, and magnetic resonance imaging (MRI) showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in most (5/6) lesions. Marked enhancement in the arterial phase was seen in 10 of 12 lesions on CT scans and in 6 of 6 lesions on MRI scans. All tumors were composed of varying proportions of smooth muscle, adipose tissue, and blood vessels, and showed positive immunohistochemical staining for HMB-45. All patients underwent partial hepatectomy and there was no evidence of recurrence after a median follow-up of 43 months. CONCLUSION: The radiological features of HAML vary according to its histological components. The definitive diagnosis of HAML is challenging and depends on the presence of HMB-45-positive myoid cells. Hepatic angiomyolipoma is treated effectively with surgery and the prognosis is good. 相似文献
992.
Bruno Guedes Baldi Alexandre Todorovic Fabro Andreia Craveiro Franco Marília Helena C Machado Robson Aparecido Prudente Estefnia Thom Franco Sergio Ribeiro Marrone Simone Alves do Vale Talita Jacon Cezare Marcelo Padovani de Toledo Moraes Eloara Vieira Machado Ferreira Andr Luis Pereira Albuquerque Marcio Valente Yamada Sawamura Suzana Erico Tanni 《Jornal brasileiro de pneumologia》2022,48(3)
993.
This study evaluated the application of quantitative tissue velocity imaging (QTVI) in assessing regional myocardial systolic and diastolic functions in dogs with acute subendocardial ischemia. Animal models of subendocardial ischemia were established by injecting microspheres (about 300 μm in diameter) into the proximal end of left circumflex coronary artery in 11 hybrid dogs through cannulation. Before and after embolization, two-dimensional echocardiography, QTVI and real-time myocardial contrast echocardiography (RT-MCE) via intravenous infusion of self-made microbubbles,were performed, respectively. The systolic segmental wall thickening and subendocardial myocardial longitudinal velocities of risk segments before and after embolization were compared by using paired t analysis. The regional myocardial video intensity versus contrast time could be fitted to an exponential function: y=A·(1-exp-β·t), in which the product of A and β provides a measure of myocardial blood flow. RT-MCE showed that subendocardial normalized A·β was decreased markedly from 0.99±0.19 to 0.35±0.11 (P〈0.05) in 28 left ventricular (LV) myocardial segments after embolization, including 6 basal and 9 middle segments of lateral wall (LW), 8 middle segments of posterior wall (PW) and 5 middle segments of inferior wall (IW). However, there was no statistically significant difference in subepicardial layer before and after embolization. Accordingly, the ratio of A·β of subendocardial myocardium to subepicardial myocardium in these segments was significantly decreased from 1.10±0.10 to 0.31±0.07 (P〈0.05). Although the systolic wall thickening did not change 5 min after the embolization in these ischemic segments (29%±3% vs 31%±5%, P〉0.05), the longitudinal peak systolic velocities (Vs) and early-diastolic peak velocities (Ve) recorded by QTVI were declined significantly (P〈0.05). Moreover, the subendocardial velocity curves during isovolumic relaxation predominant 相似文献
994.
995.
996.
In order to explore the expression of PI-3K in T lymphocytes of asthmatic rats and the relationship between PI-3K and activation of T lymphocytes, 24 Wistar rats were randomly divided into 4 groups: normal control group, asthmatic one-week group, asthmatic two-week group and asth-matic four-week group. T cells were purified from blood of each rat and the expression of PI-3K was observed by immunocytochemical fluorescence staining, the semiquantitative fluorescence intensity was measured by HPIAS-2000 analytic software, and the expression of IL-4 in supernatants was de-tected by ELISA. The results showed that the fluorescence intensity of T lymphocytes in asthmatic groups was significantly higher than that in normal control (P<0.001), indicating that the expression of PI-3K in T lymphocytes of asthmatic rats was significantly higher than that in those of normal controls, and the difference between acute and chronic stage asthmatic groups was significant (P<0.05). The expression levels of IL-4 protein in supernatants of asthmatic T lymphocytes were sig-nificantly higher than those in the normal controls (P<0.05). There was a significant positive correla-tion between the expression of PI-3K in T lymphocytes and the IL-4 protein expression in super-natants (r=0.583, P<0.01). It was suggested that PI-3K signal pathway may participate in the proc-esses of activation and other cytological effects of asthmatic T lymphocytes, thus may play an impor-tant roles in the pathogenesis of asthma. 相似文献
997.
998.
Whether inhibiting the activity of nuclear factor (NF)-κB potentiates cisplatin-induced apoptosis in non-small cell lung cell line A549 cells was investigated. The recombinant plasmid pcDNA3.1(+)/IκBα expressing IκBα was constructed. The in vitro cultured A549 cells were transfected with pcDNA3.1 (+)/IκBα alone, or pcDNA3.1(+)/IκBα combined with cisplatin. The mitochondrial membrane potential (△ψm) was determined by rhodamine 123, the activity of caspase-3 was tested by colorimetric assay, and cell apoptosis was detected by flow cytometry with the annexin V/propidium iodide assay. The results showed that the activity of NF-κB in A549 cells was inhibited by transfecting pcDNA3.1(+)/IκBα. Transfection of pcDNA3.1(+)/IκBα alone did not promote apoptosis. Treatment of cisplatin alone had a little effect on cell apoptosis. Transfection of pcDNA3.1(+)/IκBα combined with cisplatin treatment significantly induced apoptosis of A549 ceils. It was concluded that inhibiting the activity of NF-κB potentiated cisplatin-induced apoptosis of A549 cells. 相似文献
999.
Ferrero A Viganò L Polastri R Muratore A Eminefendic H Regge D Capussotti L 《World journal of surgery》2007,31(8):1643-1651
Background The future remnant liver (FRL) limit for safe major hepatectomy with low risk of postoperative liver failure has not yet been
well defined.
Methods Between April 2000 and September 2004, every patient scheduled for major hepatectomy in our institution underwent CT-volumetry
of FRL. Patients with FRL <25% underwent portal vein embolization (PVE). Exclusion criteria were PVE, associated vascular
resection and liver cirrhosis. The FRL was correlated with short-term results in patients with normal liver (group A) and
those with impaired liver function secondary to neoadjuvant chemotherapy or cholestasis (bilirubin >2 mg/100 ml) (group B).
Liver dysfunction was defined as both PT <50% and serum bilirubin level >5 mg/100 ml for three or more consecutive days.
Results A total of 119 patients were analyzed, 72 in group A and 47 in group B. The FRL value was the only significant risk factor
for postoperative liver dysfunction in the univariate and multivariate analysis (p = 0.009). The FRL did not correlate with postoperative mortality and morbidity. Bilirubin and prothrombin time (PT) on days
3 and 7 were significantly correlated to FRL in both groups. In group A, patients with postoperative liver dysfunction had
a FRL<30% (3 versus 0; p = 0.005). According to receiving operator characteristic (ROC) curve analysis, a FRL value of 26.5% predicted postoperative
liver dysfunction with 66.7% sensitivity, 97.1% specificity, 50% positive predictive value (PPV), and 98.5% negative predictive
value (NPV). In group B, patients with postoperative liver dysfunction had a FRL <35% (4 versus 0; p = 0.027). According to ROC curve analysis, a FRL value of 31.05% predicted postoperative liver dysfunction with 75% sensitivity,
79.1% specificity, 25% PPV, and 97.1% NPV.
Conclusions Hepatectomy can be considered safe when FRL is >26.5% in patients with healthy liver and >31% in patients with impaired liver
function. 相似文献
1000.
Robotic surgery is being performed more frequently for a variety of urologic procedures. Since the first robotic adrenalectomy
less than a decade ago, this modality has gained increased acceptance in the urologic community and has been employed with
increased frequency in minimally invasive centers. This review evaluates the current literature on robotic adrenalectomy,
its indications, as well as its advantages and limitations compared with other forms of surgical management of adrenal pathology. 相似文献