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991.
992.
We report 3 cases of muscle tension dysphonia (MTD), all involving women 44 to 68 years old, recovered using proton pump inhibitors (PPI). Case 1 had open posterior commissure (MTD Type I) and Cases 2 and 3 supraglottis compression (MTD Type II, III). It is generally assumed that functional dysphonia with maladjustment of laryngeal muscle tension is caused by improper phonation and/or emotional disorder. Our cases, however, suggest that laryngopharyngeal reflux (LPR) may also relate to the occurrence of MTD.  相似文献   
993.
Ultrasound can be perceived by bone conduction, and its characteristics differ from those of air-conducted audible sound (ACAS) in some respects. Despite many studies on ultrasonic hearing, the details have not yet been clarified. In this study, to elucidate the perception mechanism, the masking of bone-conducted ultrasound (BCU) produced by ACAS and the sensitivity of BCU in hearing impaired subjects were evaluated. We found that BCU was masked by high frequency ACAS, especially in the frequency range of 10-14 kHz. The most effective masker frequency depended on masker intensity. For hearing impaired subjects, the pure tone thresholds at 1-8 kHz and the maximum audible frequencies at cut-off intensities of 70-100 dB HL were significantly associated with the BCU threshold (p < 0.01 or p < 0.05). No subjects with estimated total loss of the inner hair cell system in the cochlear basal turn could hear BCU. These results suggest the peripheral perceptual region to be located in the cochlea. The results of masking show the faster excitation spread to the lower frequency range, depending on the intensity. This faster excitation spread may be due to nonlinearity in cochlear mechanics, which may work even without cochlear amplifier, and induce unique characteristics of BCU.  相似文献   
994.
For a large hepatic neoplasm existing in the right hepatic lobe, hepatic resection using an anterior approach is required. We have reported an operative procedure for hepatic transection using absorbable polyglycolic acid tape. In patients with suspected tumor invasion of the inferior vena cava, on the other hand, considering the range of the residual tumor while sparing the inferior vena cava as much as possible, combined resection and reconstruction of the inferior vena cava is conducted only if operative curativity is expected. We conducted hepatic transection while maintaining the blood flow of the residual liver by applying the liver hanging maneuver method of Belghiti et al. and polyglycolic acid tape in patients with giant liver tumors of the right hepatic lobe compressing the hepatic inferior vena cava. Strong angled dissecting forceps were inserted into the ventral side of the inferior vena cava from the caudal side, and the tip was induced between hepatic veins. Two strips of polyglycolic acid tape were pinched with forceps and strongly ligated on the right and left sides of the cutoff line. Subsequently, hepatic transection was conducted using electrocautery spray coagulation and CUSA without blocking the inflow blood of the residual liver, and the right hepatic lobe was extirpated. This procedure has already been performed in 5 patients suspected of inferior vena cava invasion, and the inferior vena cava was able to be preserved in all the patients.  相似文献   
995.
Left ventricular (LV) aneurysm has been recognized to frequently become a substrate of ventricular tachyarrhythmias. We report a case of a 66-year-old woman with symptomatic sustained monomorphic ventricular tachycardia (SMVT) originating from saccular apical LV aneurysm without definite underlying diseases. We performed catheter ablation using electroanatomical and conventional bipolar potential mapping. During SMVT, we found an area of fragmented potential -40 ms preceding the earliest wide QRS complex in the area of the apical LV aneurysm. Radiofrequency applications were delivered to this area. Since then, SMVT was no longer inducible by programmed electrical stimulation. The patient has remained free of VT recurrences during a subsequent 12-month follow-up period.  相似文献   
996.
Pelus LM  Bian H  King AG  Fukuda S 《Blood》2004,103(1):110-119
Mobilized peripheral blood stem cells (PBSCs) are widely used for transplantation, but mechanisms mediating their release from marrow are poorly understood. We previously demonstrated that the chemokines GRObeta/CXCL2 and GRObetaT/CXCL2Delta4 rapidly mobilize PBSC equivalent to granulocyte colony-stimulating factor (G-CSF) and are synergistic with G-CSF. We now show that mobilization by GRObeta/GRObetaT and G-CSF, alone or in combination, requires polymorphonuclear neutrophil (PMN)-derived proteases. Mobilization induced by GRObeta/GRObetaT is associated with elevated levels of plasma and marrow matrix metalloproteinase 9 (MMP-9) and mobilization and MMP-9 are absent in neutrophil-depleted mice. G-CSF mobilization correlates with elevated neutrophil elastase (NE), cathepsin G (CG), and MMP-9 levels within marrow and is partially blocked by either anti-MMP-9 or the NE inhibitor MeOSuc-Ala-Ala-Pro-Val-CMK. Mobilization and protease accumulation are absent in neutrophil-depleted mice. Synergistic PBSC mobilization observed when G-CSF and GRObeta/GRObetaT are combined correlates with a synergistic rise in the level of plasma MMP-9, reduction in marrow NE, CG, and MMP-9 levels, and a coincident increase in peripheral blood PMNs but decrease in marrow PMNs compared to G-CSF. Synergistic mobilization is completely blocked by anti-MMP-9 but not MeOSuc-Ala-Ala-Pro-Val-CMK and absent in MMP-9-deficient or PMN-depleted mice. Our results indicate that PMNs are a common target for G-CSF and GRObeta/GRObetaT-mediated PBSC mobilization and, importantly, that synergistic mobilization by G-CSF plus GRObeta/GRObetaT is mediated by PMN-derived plasma MMP-9.  相似文献   
997.
BACKGROUND: Oolong tea has been studied for its effect on cardiovascular disease and obesity. Plasma adiponectin levels are reduced in obesity, in patients with type 2 diabetes mellitus and in coronary artery disease (CAD). OBJECTIVE: To investigate prospectively, whether intake of Oolong tea influences plasma adiponectin levels, low-density lipoprotein (LDL) particle size, total cholesterol, high-density lipoprotein (HDL) cholesterol, LDL cholesterol, serum triglyceride and plasma glucose levels in patients with CAD. METHODS: Twenty two patients in our study consumed Oolong tea (1000 ml) or water for 1 month in our randomized cross-over study design. RESULTS: There was a significant difference in plasma adiponectin levels before and after 1 month intake of Oolong tea (6.26 +/- 3.26 microg/ml versus 6.88 +/- 3.28 microg/ml, P < 0.05), and in plasma level LDL particle size (25.02+/-0.67 nm versus 25.31+/-0.60 nm, P < 0.01). The water-consuming control group showed no changes (6.28+/-3.28 microg/ml versus 6.23+/-3.21 microg/ml) in adiponectin levels or LDL particle sizes (25.03+/-0.70 nm versus 25.02+/-0.72 nm). We also observed a significant difference in hemoglobin A1c levels (7.23 +/- 4.45% versus 6.99 +/- 4.30%, P < 0.05) before and after intake of Oolong tea. CONCLUSION: Oolong tea may have beneficial effects on the progression of atherosclerosis in patients with CAD.  相似文献   
998.
BACKGROUND: Measurement of left ventricular (LV) volumes and ejection fraction (EF) is important in managing patients with coronary artery disease (CAD). Introduction of free-hand three-dimensional echocardiography (3DE) system which is equipped with small magnetic tracking system and average rotational geometry for LV volumes may provide easy and accurate quantification of LV systolic function in CAD patients. PURPOSE: To evaluate the feasibility and accuracy of LV volumes and EF measurement by free-hand 3DE with rotational geometry in patients with CAD. METHODS AND RESULTS: The study subjects consisted of consecutive 25 patients with CAD who were scheduled for quantitative gated single-photon emission computed tomography (QGS). LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF were determined by conventional two-dimensional echocardiography (2DE), 3DE, and QGS. Three-dimensional echocardiography data acquisition and analysis were possible in 22 of 25 subjects (feasibility 88%). In this 3DE system, image acquisition time was 2 minutes, and 5 minutes were needed for off-line analysis of LV volumes and EF. Correlations and the limits of agreement between 3DE and QGS (r = 0.97, 0.0 +/- 9.1 ml for EDV, r = 0.99, 0.0 +/- 5.0 ml for ESV, and r = 0.97, 0.5 +/- 3.3% for EF, respectively) were superior to those between 2DE and QGS (r = 0.85, 12.6 +/- 26.8 ml for EDV, r = 0.85, 9.7 +/- 26.1 ml for ESV, and r = 0.90, -1.3 +/- 6.9% for EF, respectively). Inter- and intra-observer variabilities of 3DE were smaller than that of 2DE (5% vs 10%, 5% vs 10% for EDV, 6% vs 13%, 5% vs 9% for ESV, and 4% vs 11%, 4% vs 6% for EF, respectively). CONCLUSION: Three-dimensional echocardiography using magnetic tracking system and average rotational geometry offered a feasible and accurate method for quantification of LV volumes and EF in patients with CAD.  相似文献   
999.
BACKGROUND: Smooth muscle cells proliferation and extracellular matrix (ECM) protein deposition are key features of diabetic macroangiopathy. In the present study, we have studied the role of endothelin(A) (ET(A)) receptor, the predominant receptor on smooth muscle cells, in diabetes-induced vascular hypertrophy and remodeling. METHODS: Streptozotocin-induced diabetic rats were administrated a selective ET(A) receptor antagonist, TBC3214, for 26 weeks. Following treatment, aortas were harvested and subjected to gene expression and morphometric analyses. We quantified fibronectin (FN) and plasminogen activator inhibitor-1 (PAI-1) expression as indicators of increased ECM protein synthesis. ET-1, ET-3, transforming growth factor-beta1 (TGF-beta1) and angiotensinogen mRNA levels were measured to elucidate genes involved in FN expression. We have investigated an embryonic splice variant of FN, oncofetal FN, and nonmuscle myosin heavy chain (SMemb) as vascular remodeling indicators. RESULTS: Our results show that diabetes leads to upregulation of FN, PAI-1, ET-1, ET-3, TGF-beta1 and angiotensinogen mRNA levels in association with increased medial thickness. Immunohistochemical analyses revealed concurrent protein level changes. Diabetes also upregulated oncofetal FN and SMemb mRNA levels. Treatment with TBC3214 attenuated the mRNA levels of several genes and prevented increased medial thickness. CONCLUSIONS: These results indicate that diabetes-induced vascular hypertrophy and remodeling is associated with reexpression of embryonic forms of FN and myosin heavy chain. Such changes are ET-dependent and may be mediated via TGF-beta1 and angiotensin.  相似文献   
1000.
OBJECTIVES: This study investigated the possibility of achieving angiogenesis by using gene-modified cells as a vector. BACKGROUND: Although gene therapy for peripheral circulation disorders has been studied intensively, the plasmid or viral vectors have been associated with several disadvantages, including unreliable transfection and uncontrollable gene expression. METHODS: Human hepatocyte growth factor (hHGF) and thymidine kinase (TK) expression plasmids were serially transfected into NIH3T3 cells, and permanent transfectants were selected (NIH3T3 + hHGF + TK). Unilateral hindlimb ischemia was surgically induced in BALB/c nude mice, and cells were transplanted into the thigh muscles. All effects were assessed at four weeks. RESULTS: The messenger ribonucleic acid expression and protein production of hHGF were confirmed. Assay of growth inhibition by ganciclovir revealed that the 50% (median) inhibitory concentration of NIH3T3 + hHGF + TK was 1000 times lower than that of NIH3T3 + hHGF. The NIH3T3 + hHGF + TK group had a higher laser Doppler blood perfusion index, higher microvessel density, wider microvessel diameter, and lower rate of hindlimb necrosis, as compared with the plasmid- and adenovirus-mediated hHGF transfection groups or the NIH3T3 group. The newly developed microvessels were accompanied by smooth muscle cells, as well as endothelial cells, indicating that they were on the arteriolar or venular level. Laser Doppler monitoring showed that the rate of blood perfusion could be controlled by oral administration of ganciclovir. The transplanted cells completely disappeared in response to ganciclovir administration for four weeks. CONCLUSIONS: Gene-modified cell transplantation therapy induced strong angiogenesis and collateral vessel formation that could be controlled externally with ganciclovir.  相似文献   
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