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BackgroundIn rectal cancer, extramural vascular invasion (EMVI) is the presence of tumour cells in blood vessels outside the muscular layer, which is associated with poor prognosis. Regression of EMVI on MRI following neoadjuvant chemoradiotherapy or its persistence may have prognostic implications.MethodsThis retrospective study included 52 patients with rectal cancer who underwent total mesorectal excision following long-course neoadjuvant chemoradiotherapy (CRT). EMVI assessments were done on previous pelvic MRIs obtained before neoadjuvant CRT and eight weeks after the completion of neoadjuvant chemoradiotherapy in initially EMVI positive cases.ResultsPersistently EMVI positive patients had worse overall survival and disease-free survival compared to initially EMVI negative patients and patients who returned to negative (p < 0.001 for both). Multivariate analysis identified persistent EMVI positivity after neoadjuvant treatment (HR, 102.9; p = 0.003) as significant independent predictor of worse overall survival; and persistent EMVI positivity (HR, 17.0; p = 0.002), mesorectal fascia involvement after neoadjuvant treatment (HR, 8.0; p = 0.017), and poor differentiation (HR, 10.3, p = 0.012) as significant independent predictors of worse disease-free survival.ConclusionPersistent EMVI positivity after neoadjuvant therapy appears to be an independent factor for poor overall survival; and persistent EMVI positivity as well as mesorectal fascia involvement on post neoadjuvant therapy MRI and poor differentiation appears to be important predictors of poor disease-free survival in rectal cancer patients.  相似文献   
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BACKGROUND: The present study was performed to assess the value of ambulatoryblood pressure monitoring (ABPM) in determining the adequacyof blood pressure (BP) control, and its relationship to echocardiographicfindings in haemodialysis (HD) patients. METHODS: We studied 40 non-diabetic adult patients who had been on regularHD treatment for a median duration of 43 months. Twenty-four-hourABPM was performed using a non-invasive ABP monitor (Pressurescan,ERKA). Casual BP (cBP) was defined as the average of two measurementsobtained at two HD sessions, one preceding and one followingthe ABP recordings, and was calculated for both the predialysisand postdialysis phases. Two-dimensional and M-mode echocardiographywere performed in each patient to determine interventricularseptal thickness (IVS), left ventricular posterior wall thickness(LVPW), left ventricular fractional shortening (FS), and leftventricular mass index (LVMI) RESULTS: According to average 24-h BP levels, 50% of the patients hadsystolic hypertension (HT) (>139 mmHg), and 72.5% had diastolicHT (>87 mmHg), while only 25% had been diagnosed as HT bycBP measurements (P>0.01 and P>0.0001 respectively). Diurnalvariation in BP was not present in about 80% of the patients.Echocardiography was normal in only four patients (10%). LVMIand LV wall thickness were correlated to ABPM data better thanto cBP measurements. Using stepwise linear regression analysis,LVMI and FVS were positively correlated with systolic BP load(P> 0.0001 and P=0.0001 respectively), and LVPW was positivelycorrelated with night-time systolic BP level (P>0.001). CONCLUSIONS: ABPM is necessary to assess the adequacy of BP control, andis well correlated to end-organ damage of HT in HD patients.  相似文献   
4.
The effects of unilateral testicular torsion on the blood flow of the contralateral testis were investigated. Fourteen adult male dogs were recruited. Seven dogs underwent unilateral testicular torsion of 4 h duration, and the other seven dogs had a control operation. Testicular blood flow was determined by colour Doppler ultrasonography before and after the testicular torsion. Bilateral orchidectomy was performed at the end of the study and histopathological changes were evaluated. Values of peak systolic velocity, end diastolic velocity, and resistive index were not statistically significant between ipsilateral and contralateral testes in the study group (p > 0.05). On comparison with the control group, blood flow in the contralateral testes showed no statistically significant difference (p > 0.05). Oedema and congestion were seen on ipsilateral testes in the study group. No histopathological changes were noted on the contralateral testes. Minimal oedema and congestion secondary to manipulation were found in the control operation testes. We conclude that unilateral testicular torsion does not decrease contralateral testicular blood flow as shown by colour Doppler ultrasonography.  相似文献   
5.
An 83‐year‐old male patient presented to the outpatient clinic with complaint of swelling at right antecubital area. Ultrasonographic examination of the right upper extremity revealed a mass lesion within the right cephalic vein, which was consistent with thrombus. A computed tomography (CT) venography showed contrast enhancement in cephalic vein at distal arm and an aneurysmatic thrombus area displaying regular borders with a size of 28*30 mm; there was no contrast enhancement at more proximal levels at the cephalic vein.  相似文献   
6.
A 42‐year‐old female patient was referred our clinic for investigation of a history of acute retinal artery occlusion. Transthoracic echocardiography showed a cyst‐like, mobile formation on posterior mitral valve leaflet. 2D and real time 3D transesophageal echocardiography showed a flexible circular mobile structure which was attached to posterior mitral valve leaflet. Echocardiographic appearance and morphological characteristics were suggestive of accessory mitral valve tissue.  相似文献   
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A 36‐year‐old female was admitted to hospital exhibiting chest pain, dyspnea, and a heart murmur on the right upper sternal border, radiating to both carotid arteries. The blood pressure of the patient's right arm exceeded the pressure in the left by 25 mm Hg (Coanda effect). In spite of laboratory results that did not fall outside the expected range, the left ventricle was revealed to be hypertrophic following electrocardiography. Transthoracic echocardiography revealed a severe supravalvular aortic stenosis (SVAS) with a peak Doppler velocity of 6.04 cm/s and an estimated mean pressure gradient of 89 mm Hg, with moderate aortic and mitral regurgitation. Contrast‐enhanced computed tomography (CCT) indicated a partial hourglass‐shaped narrowing of the ascending aorta. Lesions associated with supravalvular stenosis of the pulmonary artery, patent ductus arteriosus, and aortic coarctation were ruled out by the CCT. Congenital SVAS is a rare heart condition, and three anatomically distinct forms have been described. The most common type is the “hourglass,” which produces a marked thickening and disorganization of the aortic tissue, producing a constricting annular ridge at the superior margin of the sinuses of Valsalva.  相似文献   
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OBJECTIVE: As the endothelium and inflammatory cells play a crucial role in the development of collaterals after a sudden or slowly progressing stenosis of coronary arteries, the levels of soluble endothelial adhesion molecules (CAMs) including vascular cell adhesion molecule (VCAM-1) intercellular adhesion molecule-1 (ICAM-1) and E-selectin were compared between patients with poor coronary collaterals and patients with well-developed collaterals. METHODS: In the study, 97 non-diabetic subjects with single-vessel disease were included. Collateral supply to the stenotic coronary artery was determined by angiographic grading system of 0-3 (Rentrop et al. J Am Coll Cardiol 1985; 5:587-592). Serum levels of adhesion molecules were measured by enzyme-linked immunosorbent assay. RESULTS: Patients were divided into two groups according to the collateral degree (group A: 50 patients with grade 0 and 1; group B: 47 patients with grade 2 and 3 collaterals). The groups were well matched with respect to baseline clinical and angiographic characteristics. Levels of soluble VCAM-1 (mean+/-SEM; 875+/-26.6 versus 742.7+/-35.1 ng/ml; P=0.004), ICAM-1 (322.4+/-12.4 versus 269.4+/-13.3 ng/ml; P=0.005), and E-selectin (43.6+/-2.6 versus 33+/-2.4 ng/ml; P=0.004) were found to be significantly higher in group A in comparison with group B. In addition, when patients were divided into four groups according to the collateral degree, patients with grade 0 collaterals had the highest values and those with grade 3 collaterals had the lowest values for all these molecules. CONCLUSIONS: We concluded that poor collateral circulation is associated with increased levels of soluble CAMs in patients with obstructive coronary artery disease. However, further studies are needed to elucidate the exact role of these inflammatory markers in the setting of poor collateral circulation.  相似文献   
9.
OBJECTIVES: To identify the risk factors for nosocomial imipenem-resistant Acinetobacter baumannii (IRAB) infections. METHODS: A prospective case-control study, set in an 1100-bed referral and tertiary-care hospital, of all patients who had nosocomial A. baumannii infections between January 1 and December 31, 2004. Only the first isolation of A. baumannii was considered. RESULTS: IRAB was isolated from 66 (53.7%) patients and imipenem-sensitive Acinetobacter baumannii (ISAB) was isolated from 57 (46.3%) patients during the study period. The mean duration of hospital stay until A. baumannii isolation was 20.8+/-13.6 days in IRAB infections, whereas it was 15.4+/-9.4 days in ISAB infections. Of the patients, 65.2% with IRAB infections and 40.4% with ISAB infections were followed at the intensive care unit (ICU). Previous carbapenem use was present in 43.9% of the patients with IRAB and 12.3% of the patients with ISAB infection. In univariate analysis female sex, longer duration of hospital stay until infection, ICU stay, emergent surgical operation, total parenteral nutrition, having a central venous catheter, endotracheal tube, urinary catheter or nasogastric tube, previous antibiotic use, and previous administration of carbapenems were significant risk factors for IRAB infections (p<0.05). In multivariate analysis, longer duration of hospital stay until A. baumannii isolation (odds ratio (OR) 1.043; 95% confidence interval (CI) 1.003-1.084; p=0.032), previous antibiotic use (OR 5.051; 95% CI 1.004-25.396; p=0.049), and ICU stay (OR 3.100; 95% CI 1.398-6.873; p=0.005) were independently associated with imipenem resistance. CONCLUSIONS: Our results suggest that the nosocomial occurrence of IRAB is strongly related to an ICU stay and duration of hospital stay, and that IRAB occurrence may be favored by the selection pressure of previously used antibiotics.  相似文献   
10.
The success of tissue engineering strategy is strongly related to the inflammatory response, mainly through the activity of macrophages that are key cells in initial immune response to implants. For engineered tissues, the presence of resident macrophages can be beneficial for maintenance of homeostasis and healing. Thus, incorporation of macrophages in engineered tissues can facilitate the integration upon implantation. In this study, an in‐vitro model of interaction was developed between encapsulated naive monocytes, macrophages induced with M1/M2 stimulation and incoming cells for immune assisted tissue engineering applications. To mimic the wound healing cascade, naive THP‐1 monocytes, endothelial cells and fibroblasts were seeded on the gels as incoming cells. The interaction was first monitored in the absence of the gels. To mimic resident macrophages, THP‐1 cells were encapsulated in the presence or absence of IL‐4 to control their phenotype and then these hydrogels were seeded with incoming cells. Without encapsulation, activated macrophages induce apoptosis in endothelial cells. Once encapsulated no adverse effects were seen. Macrophage‐laden hydrogels attracted more endothelial cells and fibroblasts compared to monocytes‐laden hydrogels. The induction (M2 stimulation) of encapsulated macrophages did not change the overall number of attracted cells; but significantly affected their morphology. M1 stimulation by a defined media resulted in more secretion of both pro‐ and anti‐inflammatory cytokines compared to M2 stimulation. It was demonstrated that there is a distinct effect of encapsulated macrophages on the behaviour of the incoming cells; this effect can be harnessed to establish a microenvironment more prone to regeneration upon implantation.  相似文献   
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