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81.
Summary In young and adult spontaneously hypertensive rats (SHR), dopamine -hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) activities in discrete areas of the brainstem and spinal cord were measured as indices of noradrenergic and adrenergic neuronal activities. In young SHR, the DBH activities were elevated in the locus coeruleus (LC), A2 cell area and thoracic intermediolateral cell area (IML). The elevation disappeared at adult SHR. In young SHR, no significant change of PNMT activity was observed in the A1, A2, nucleus tractus solitarii (NTS), LC and IML areas, while, in adult SHR, the PNMT activity in the A1 cell area and DBH activity in the NTS were elevated. Lowering of blood pressure by hydralazine decreased the PNMT activity elevated in the A1 cell area and elevated it in the NTS.Plasma levels of norepinephrine and epinephrine, as measured in blood samples collected via aortic cannula at resting state, were much lower than many reported values in blood collected from the decapitated trunk. In young SHR, a significant elevation of plasma norepinephrine and DBH levels was confirmed as signs of peripheral sympathetic nervous activation. The elevation disappeared at adult SHR. Plasma epinephrine levels raised under restraint stress were much higher in SHR at all ages than in normotensive controls.In young SHR, the selective activation of noradrenergic neurons of the IML, A2 and LC areas, accompanied by activation of the peripheral sympathetic nervous system, initiates the hypertension. In adult SHR, the activation of adrenergic neurons in the A1 cell area including the nucleus reticularis lateralis may not be involved in the maintenance of hypertension but may be the results of hypertension.  相似文献   
82.
Severity of negative esophageal pressure (Pes) and apnea hypopnea index (AHI) were investigated in six cases of upper airway resistance syndrome (UARS) and 11 cases of obstructive sleep apnea syndrome (OSAS). The severity of negative Pes was represented by the highest peak (Pes Max) and the number of increased episodes (more than 13.5 cmH2O) per h (NPesI13.5). There was no significant correlation between Pes indices and AHI. Pes Max and NPesI13.5 were not different among severe OSAS (AHI > 30), mild OSAS (AHI < 30) and UARS. Apnea hypopnea index failed to represent the severity of negative Pes, which is an important aspect of the pathophysiology of sleep-disordered breathing.  相似文献   
83.
In the 22 years between March 1979 and February 2001, we treated 16 patients--10 men and 6 women aged 10-80 years (mean: 44 years)--with mucoepidermoid carcinoma (MEC) of the salivary gland, evaluating them clinically and histopathologically. Tumor sites included 12 at the parotid gland, 3 at the submandibular gland, and 1 at the minor salivary gland. All tumors were graded histopathologically based on the criteria of Goode et al. as follows: low grade (n = 10), intermediate grade (n = 1), and high grade (n = 5). Female gender was associated with low grade MEC and male gender with high grade MEC (P < 0.05). The age at onset in high grade MEC was older than that in low grade MEC (P < 0.005). Lymph-node metastasis was detected in 7 out of the 16 patients (44%) associated significantly with high grade MEC (P < 0.05). Distant metastasis was detected in 4 of 16 patients (25%). Distant metastasis was significantly associated with high grade MEC (P < 0.05). Local recurrence was detected in 3 of 15 patients undergoing surgery (20%). No difference was seen in local recurrence frequency between low and high grade MEC. Survival was calculated with Kaplan-Meier's method. In all 16, 5-year survival was 86% and 10-year survival 75%. Five-year survival in low grade MEC was 100%, whereas that in high grade MEC was 67% (P < 0.05). In MEC of the salivary gland, it was suggested that the histopathological MEC grade evaluated by Goode's criteria significantly correlated with gender, age, lymph-node metastasis, distant metastasis, and 5-year survival.  相似文献   
84.
To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases.  相似文献   
85.
OBJECTIVES: Decreased proprioception may contribute to the risk of falls in elderly patients. The purpose of this study is to determine whether patients with hip fractures have decreased hip proprioception compared with aged-matched controls, and whether hip proprioception differs in patients with repaired fractures compared with patients who have undergone prosthetic hip replacement after hip fracture. DESIGN: Retrospective. PATIENTS/PARTICIPANTS: Both hips of twenty-four hip fracture patients and age-matched patients without hip fractures were studied. Hip fracture patients were divided into osteosynthesis (twelve hips) and hemiarthroplasty (twelve hips) groups. INTERVENTION: Reproducibility of index angles (thirty hip flexion and thirty hip abduction) were compared with a six-degree-of-freedom electrogoniometer (instrumented spatial linkage; angular accuracy +/-0.5 degrees). RESULTS: There was no significant difference (flexion, p > 0.20; abduction, p > 0.67) in joint proprioception between fracture and no fracture groups. Likewise, there was no difference (flexion, p > 0.99, abduction; p > 0.74) in joint proprioception between osteosynthesis and hemiarthroplasty groups. CONCLUSIONS: Joint proprioception of hip fracture patients was not found to be diminished compared with age-matched normal controls. Additionally, replacement of the femoral head did not reduce joint proprioception compared with osteosynthesis with an intact femoral head. Maintenance of the femoral head does not seem to be necessary for the maintenance of joint proprioception in elderly hip fracture patients.  相似文献   
86.
Subependymoma of the septum pellucidum: Characterization by PET   总被引:1,自引:0,他引:1  
We report the evaluation of a subependymoma of the septum pellucidum by positron emission tomography (PET) with analysis of 18F-fluorodeoxyglucose (FDG)kinetics. The tumor showed exceedingly low rates of glucose metabolism (rCMRG1) and kinetic constants (K1, K2, and K3). This hypometabolism indicates low cellular density and slow growth.  相似文献   
87.
Treatment of Lethal Midline Granuloma Type Nasal T-Cell Lymphoma   总被引:7,自引:0,他引:7  
Nasal T-cell lymphoma of the LMG type (LMG-NTL) is characterized by progressive, unrelenting ulceration, and necrosis of the nasal cavity and midline facial tissues. The clinical behavior of this tumor in 16 patients is compared with that of a nasal lymphoma of non-LMG-NTL type (non-LMG-NTL) in 8 patients and a paranasal sinus lymphoma (PSL) in 6 patients. All patients had stage I or II disease. Fourteen of the 16 patients with LMG-NTL received chemotherapy before and/or after radiotherapy. Cause-specific 5-year survival rates for patients with LMG-NTL, non-LMG-NTL, and PSL were 22%, 75%, and 67%, respectively. Seven patients with LMG-NTL, had complete response, although 3 recurred, whereas it was incomplete in 9 patients. The data indicates that it is desirable to deliver 50 Gy or more to achieve in-field control of LMG-NTL.  相似文献   
88.
We report a 3-month-old girl with Costelio syndrome complicating fatal hypertrophic obstructive cardio-myopathy. She had typical findings of this syndrome, slight dyspnea and persistent wheezing. Doppler echocardiography revealed asymmetric septal hypertrophy and systolic anterior movement of the anterior mitral leaflet. There was grade 1 mitral regurgitation. Although once her heart failure had been controlled medically, she died suddenly following deterioration of her heart condition. Costelio syndrome can complicate fatal hypertrophic obstructive cardiomyopathy.  相似文献   
89.
90.
In the present study, we found that inostamycin increased the ability of paclitaxel to induce apoptosis in Ms-1 cells. A considerably higher concentration of paclitaxel was required for the induction of apoptosis in Ms-1 cells than in other cell lines tested. Treatment of Ms-1 cells with inostamycin, an inhibitor of phosphatidylinositol (PI) synthesis, reduced the dosage of paclitaxel required to induce cell death by apoptosis. This effect of inostamycin is specific to Ms-1 cells, and inostamycin did not increase the cytotoxicity of other antitumor drugs such as adriamycin, vinblastine, methotrexate, cisplatin, etoposide, or camptothecin in Ms-1 cells. Addition of inostamycin to paclitaxel-treated cells caused a significant increase in the sub G1 peak, representing apoptosis, which was accompanied by a decrease in the G2/M peak seen in paclitaxel-treated Ms-1 cells, without affecting paclitaxel-inhibited tubulin depolymerization. Moreover, paclitaxel did not enhance inostamycin-inhibited PI synthesis. The expression levels of Bcl-2, Bax, and Bcl-XL were not changed following the co-treatment with inostamycin plus paclitaxel, whereas the activated form of caspase-3 was markedly increased. Thus, inostamycin is a chemosensitizer of paclitaxel in small cell lung carcinoma Ms-1 cells.  相似文献   
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