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101.
The reliability of quantitative coronary angiography (QCA) measurements is of fundamental importance for the study and practice of interventional cardiology. In vivo validation results have consistently reported a tendency for QCA systems to overestimate small luminal diameters. Such a systematic error may result in the underestimation of luminal gain during intracoronary procedures and in the underestimation of progression of coronary artery disease during longitudinal studies. We report the in vivo validation results of an experimental adaptive edge-detection algorithm that was developed to reduce overestimation of small luminal diameters by incorporating a dynamic function of variable kernel size of the derivative operator and variable weighting of the first and second derivatives of the brightness profile. The results of the experimental algorithm were compared to those of the conventional parent edge detection algorithm with fixed parameters. Dynamic adjustment of the edge-detection algorithm parameters was found to improve measurements of small (lt;0.8-mm) luminal diameters as evidenced by an intercept of +.07 mm for the algorithm with variable weighting compared to +0.21 mm for the parent algorithm with fixed weighting. A slope of <1 was found for both the parent and experimental algorithms with subsequent underestimation of large luminal diameters. Systematic errors in a QCA system can be identified and corrected by the execution of objective in vivo validation studies and the consequent refinement of edge-detection algorithms. The overestimation of small luminal diameters may be overcome by the incorporation of a dynamic edge-detection algorithm. Further refinements in edge-detection algorithms will be required to address the issue of underestimation of large luminal diameters before the absolute values derived from QCA measurements can be considered accurate over the full range of clinically encountered luminal diameters. © 1995 Wiley-Liss, Inc.  相似文献   
102.
103.
Crow-Fukase syndrome (CFS) is a multisystemic disorder. Because it is characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, sclerotic bone lesions, and skin changes it is also known as POEMS syndrome. Extravascular volume overload is also one of the main symptoms. Uncontrollable extravascular volume overload is one of the major causes of death and one of the negative prognostic factors. Control of the extravascular volume overload is an important therapeutic strategy for this syndrome. We report here a case of CFS with extravascular volume overload resulting in pleural effusion and massive edema in the lower extremities, which was refractory to oral administration of melphalan and prednisolone. The patient's condition correlated with the serum level of vascular endothelial growth factor and markedly improved after administration of high-dose melphalan (200 mg/m2) followed by autologous peripheral blood stem cell transplantation. This approach should be considered in patients with CFS who fail to respond to conventional chemotherapy and have uncontrollable extravascular volume overload.  相似文献   
104.
A 32-year-old man with lung cancer involving pericarditis carcinomatosa underwent pericardiotomy, using an Inoue balloon dilating catheter, to create a non-surgical pericardial window. The procedure was performed from the thoracic wall to the left pleural effusion and parietal pericardium under local anesthesia. The effects of non-surgical pericardial window had been maintained until this patient died from his primary disease. It is concluded that percutaneous balloon pericardiotomy is helpful in the management of massive pericardial effusions particularly in patients with malignancies and poor clinical condition  相似文献   
105.
There is increasing evidence that peripheral pulse pressure measured at the brachial artery is a good predictor of coronary heart disease. However, the relation between pulse pressure and angiographically demonstrated coronary artery stenosis has not been fully elucidated. We designed the present study to investigate the association of the various components of blood pressure, such as systolic pressure, diastolic pressure, and pulse pressure of both peripheral and central arteries with angiographically determined coronary artery stenosis. Levels of aortic systolic pressure, aortic diastolic pressure, aortic pulse pressure, peripheral systolic pressure, peripheral diastolic pressure, and peripheral pulse pressure were determined in 323 patients who underwent diagnostic coronary angiography. Of these 323 patients, 215 patients had significant organic coronary artery stenosis. Aortic pulse pressure was significantly higher in patients with coronary artery stenosis (P = 0.0050). Aortic diastolic pressure was lower in patients with coronary artery stenosis (marginally significant, P = 0.0462). However, no statistically significant difference was observed between other blood pressure components and coronary artery stenosis. Multivariate analyses showed that aortic pulse pressure was associated with coronary artery stenosis independently of aortic diastolic pressure. Moreover, aortic pulse pressure was positively correlated with the number of vessels involved (P = 0.0024). The results of the present study indicate that aortic pulse pressure is significantly and independently correlated with angiographically determined coronary artery stenosis.  相似文献   
106.
We prospectively evaluated the disease-specific features of the early postoperative plasma D: -dimer value and the relationship with deep venous thrombosis and/or pulmonary thromboembolism (DVT/PE) in 95 patients following total knee arthroplasty. Patients in whom DVT/PE was highly suspected were diagnosed by high-resolution multi-detector row computed tomography scanning (MDCT). Forty-nine knees in 46 patients with rheumatoid arthritis (RA, 24 knees) or osteoarthritis (OA, 25 knees) were finally recruited. DVT/PE was detected in 28 (57.1%) of the 49 cases examined by diagnostic MDCT: 12 (50.0%) of the 24 cases of RA, and 16 (64.0%) of the 25 cases of OA. Of these, PE was found in 11 cases (39.2%), but none of them showed clinical symptomatic signs of dyspnea or chest pain. In both RA and OA cases, there were statistically significant differences in the D: -dimer value on postoperative day 3 (P = 0.027) and after day 28 (P = 0.037) between the groups with and without DVT/PE. In OA cases, there were significant differences between the two groups on postoperative days 1 (P = 0.034), 3 (P = 0.020), 5 (P = 0.005), and 7 (P = 0.045), respectively. At the baseline, perioperative D: -dimer levels in the RA group without DVT/PE were higher than in the OA group. However, multivariate logistic regression analysis showed that RA was not a significant risk factor of DVT/PE in comparison with OA. In conclusion, individual evaluation of the D: -dimer level between RA and OA should provide a more precise predictive indicator of early postoperative DVT/PE.  相似文献   
107.
Dopamine may be a modulator of aldosterone secretion in man. Whether this effect is extraadrenal or is exerted directly at the adrenal gland via local dopaminergic receptors remains uncertain. This study examined the possibility that dopaminergic binding sites exist in the human adrenal cortex using [3H]spiperone, a butyrophenone with high affinity for dopaminergic receptors of the D2 subtype. [3H]Spiperone binding to membranes prepared from the outer adrenal cortex obtained from eight patients undergoing adrenalectomy was studied. Specific [3H]spiperone binding, defined as binding displacable by 250-fold excess of unlabeled spiperone reached equilibrium within 30 minutes at 4 degrees C and was readily reversible. Binding was consistent with both high affinity (Kd1 = 0.2 to 0.8 nmol/L) and low affinity (Kd2 = 20 to 127 nmol/L) binding states. Binding capacity was 27 to 276 fmol/mg for the high affinity and 63 to 597 fmol/mg for the low affinity binding state. The relative potency in inhibition of [3H]spiperone binding was as follows: antagonists, spiperone greater than domperidone greater than metoclopramide greater than ketanserin greater than (-) sulpiride greater than (+) sulpiride; agonists, dopamine, bromocriptine greater than NPA much much greater than epinephrine. Serotonin and norepinephrine did not affect [3H]spiperone binding. These data suggest the existence of dopaminergic binding sites possibly of the D2 subtype in the human adrenal cortex. The precise location of these sites remains to be determined.  相似文献   
108.
Neuroinflammation in the brain is thought related to the emergence of various psychoses,although the identifying regional significance,the involvement of immune-cells and lymphocytic activity,and ways for the therapeutic recovery are under the effort of researchers.We recently revealed that the cerebellar acute inflammation causes the symptoms manifested in mood disorders or developmental disorders,which were associated with hyperexcitability due to immune-triggered plasticity and the overconnectivity between the inflamed cerebellum and prefrontal cortex(Yamamoto et al.,2019).  相似文献   
109.
ObjectivePrevention is difficult to decrease dental caries only via the partial application of fluoride. The GC Co. has developed a coating material adhesive containing fluoride and zinc. It is thought that this zinc has an effect which prevents dental caries. The aim of this study was to evaluate the influence of the Caredyne Shield® (CS) on biofilm generation by S. mutans, as compared to an acidulated phosphate fluoride (APF) gel.Materials and methodsWe performed the comparative study of the biofilm inhibitory effect which used the enamel of bovine teeth. Specimens were separated into a control group, an APF gel group, and a CS group. Biofilms were generated by adherent S. mutans. We observed the antibacterial weigh by the creation state of Biofilms.ResultsSignificant difference was observed in the number of bacterial colonies formed after 24 h, the number of bacterial colonies formed from detached S. mutans from the CS-treated experimental group were fewer in number than in the other group (p < 0.01). The biofilm formed by S. mutans 72 h after dissemination on the enamel surface was visible by fluorescence microscopy (Live/Dead staining method) and under the scanning electron microscope, in the CS-treated group, no plastic structures were observed, as the models were free of the biofilm and only scattered S. mutans cells were observed.ConclusionWe showed in this study the efficacy of CS in controlling the formation of biofilm. From such a result, we conclude that CS is a novel anticaries agent.  相似文献   
110.
We examined the effects of high-intensity resistance training (HIT) and low-intensity blood flow-restricted (LI-BFR) resistance training on carotid arterial compliance. Nineteen young men were randomly divided into HIT (n = 9) or LI-BFR (n = 10) groups. The HIT and LI-BFR groups performed 75 and 30 %, respectively, of one-repetition maximum (1-RM) bench press exercise, 3 days per week for 6 weeks. During the training sessions, the LI-BFR group wore elastic cuffs around the most proximal region of both arms. Muscle cross-sectional area (CSA), 1-RM strength, and carotid arterial compliance were measured before and 3 days after the final training session. Acute changes in systolic arterial pressure (SAP), plasma endothelin-1 (ET-1), nitrite/nitrate (NOx), and noradrenalin concentrations were also measured during and after a bout of training session. The training led to significant increases (P < 0.01) in bench press 1-RM and arm and chest muscle CSA in the two training groups. Carotid arterial compliance decreased significantly (P < 0.05) in the HIT group, but not in the LI-BFR group. There was a significant correlation (r = ?0.533, P < 0.05) between the change in carotid arterial compliance and the acute change in SAP during training sessions; however, ET-1 and NOx did not correlate with carotid arterial compliance. Our results suggest that muscle CSA and strength increased following 6 weeks of both HIT and LI-BFR training. However, carotid arterial compliance decreased in only the HIT group, and the changes were correlated with SAP elevations during exercise sessions.  相似文献   
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