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81.
We previously reported the hyperosmolarity response (a decrease of the ocular standing potential by hyperosmolarity) as a new clinical test of the retinal pigment epithelium (RPE) activity. In the present study a hypertonic solution (Fructmanit, 1.4 × 103 m0sm/1) was intravenously injected for 20 min in proportion to a subject's total blood volume (TBV). At the injection speed of 5, 10, and 15% of the subjects' TBV per hour the mean amplitude of the hyperosmolarity response in normal subjects was 19.7, 30.1 and 36.4% respectively. The amplitude of the hyperosmolarity response depends on the logarithm of the dose of the hypertonic solution within the range of the dose tested.We previously found that hyperosmolarity suppresses the light rise. The present study investigated this suppressive effect in a quantitative manner. The light rise (a full-field illumination of 1.2 × 103 cdl/m2) was dose-dependently suppressed by Fructmanit. The mean of the light rise to dark trough ratio in normal subjects was 1.81 with no osmotic stress, and 1.64, 1.41 and 1.29 respectively at the injection speeds of 5, 10, and 15%. The suppression of the light rise by hyperosmolarity is compatible with the view that the hyperosmolarity response and the light rise share the basal membrane of the RPE as the main site of their generation.  相似文献   
82.
Abstract: We have evaluated the relationship between bone mass and mechanical properties of bone from male and female rats treated with YM175, a novel bisphosphonate, for 104 weeks. YM175 [disodium (cycloheptylamino) methylenediphosphonate monohydrate] was given via the drinking water at a concentration of 0, 0.005, 0.015, 0.05, or 0.15%. Since the mortality in the male 0.15% group exceeded the exclusion criteria (75%) at week 88, this group was omitted from the study. Mean daily intake of YM175 was 2.2-22.1 mg/kg for males and 3.6-104 mg/kg for females. After the treatment, mechanical properties and ash weight of the humerus were determined. In males, 0.015 and 0.05% of YM175 (6.6–22.1 mg/kg) significantly increased failure load of the midshaft. In females, failure load and stiffness of the midshaft tended to be increased by YM175 (up to 104 mg/kg). Furthermore, ultimate compressive load at the humeral metaphysis treated with the highest dose of YM175 was 2- or 3.5-fold greater than that of untreated male or female control. Ash weight of the humerus was increased dose-dependently and was positively correlated with failure load of the midshaft. These findings indicate that treatment for 2 years with YM175 increased bone mass and mechanical strength without blocking bone mineralization.  相似文献   
83.
Background. [123I]Metaiodobenzylguanidine (MIBG) imaging has been used to assess cardiac sympathetic nerve abnormalities. We evaluated the clinical significance of myocardial MIBG imaging as a measure of cardiac sympathetic nervous system function by comparing it to heart rate variability and plasma norepinephrine level.Methods and Results. In 211 subjects, we analyzed heart rate variability with 24-hour electrocardiography, performed scintigraphy with MIBG, and measured plasma norepinephrine levels. Time and frequency domain measures of heart rate variability were calculated with the Marquette heart rate variability program (Marquette Electronics, Milwaukee, Wis.). Early and late myocardial MIBG uptakes were measured at 15 and 150 minutes after injection, respectively. MIBG clearance rate from the heart and heart-to-lung and heart-to-mediastinum ratios of MIBG activities were calculated. On the whole, heart rate variability, including low-frequency power, correlated positively, but modestly so, with late MIBG uptake and negatively with MIBG clearance rate. The plasma norepinephrine level correlated negatively with late MIBG uptake and with heart rate variability, including low-frequency power, and positively with MIBG clearance rate. Similar correlations were also observed in patient subgroups with coronary artery disease, diabetes mellitus, and renal failure, but these correlations were weak (R2 < 0.5).Conclusions. Increased cardiac sympathetic nervous system activity may be associated with increased myocardial MIBG clearance and decreased heart rate variability, including low-frequency power. Because these associations were not strong, however, the combination of heart rate variability with MIBG may allow an interactive assessment of the cardiac autonomic nervous system.  相似文献   
84.
Although the dry powder type inhaled steroids, such as Fluticasone Propionate Diskhaler (FP-DH), FP Diskus (FP-DK), Budesonide Turbuhaler (BUD-TH), are widely distributed in daily clinical fields, we clinicians are required to evaluate whether it is effectively inhibiting inflammation of distal airway or not. We also investigated the effect of Hydrofluoroalukan-beclomethasone dipropionate (HFA-BDP), a new type of inhaled steroid which forms super micro aerosol particles, in the distal small airway. METHOD: 85 patients with moderate asthma, who daily used dry powder type inhaled steroid for at least more than 6 months with stable asthmatic condition, were the subject of this study. All subjects underwent sputum induction with the inhalation of 10% of hypertonic saline solution for 15 min and eosinophil counts and eosinophil cationic protein (ECP) in individual induced sputum were measured. Then, patients who had eosinophils detected in their induced sputum changed their previously inhaled steroid to HFA-BDP inhalation (400 i.g./day). Their eosinophil counts and the values of eosinophil cationic protein (ECP), Eotaxin, RANTES and neutrophil elastase (PMN-E) in their induced sputum were also examined before and 4weeks after changing HFA-BDP inhalation. RESULT: Increased eosinophils were found in the induced sputum of 40.5% patients of the FP-DK group, 36.3% of the FP-DH group and 32.4% of the BUD-TH group, respectively. Compared with group of patients in which no sputum eosinophil were detected, the sputum ECP values, in which sputum eosinophils were detected, were significantly high. 4 weeks after changing to HFA-BDP inhalation, eosinophil counts, ECP, Eotaxin, RANTES and PMN-E in their induced sputum were decreased in every group. CONCLUSION: Compared with the ordinary dry powder type inhaled steroids, HFA-BDP can effectively diminish distal airway inflammation, suggesting the possibility that HFA-BDP can effectively reach to the distal small airway by forming super micro aerosol particles.  相似文献   
85.
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor.  相似文献   
86.
To study the hemodialysis period following cadaveric renal transplantation, we reviewed 18 consecutive cadaver donor kidney pairs of which one kidney was transplanted at Shiga University of Medical Science (SUMS) while the contralateral kidney was transplanted at Kyoto Prefectural Medical University (KPMU) between January 1983 and September 1988. Of these 18 pairs, graft function was satisfactory and the recipient was free from hemodialysis in 13 pairs. However, the postoperative hemodialysis periods were different between the two centers. To clarify the factors causing this difference, recipient factors, such as age, HLA matching, total ischemic time of the graft (TIT), immunosuppression, onset of diuresis and postoperative complications were studied. There were no significant differences in age, HLA matching, or immunosuppression. TIT of cases at SUMS was significantly longer than that of cases at KPMU. The postoperative hemodialysis period at SUMS was 25.8 days and that at KPMU was 17.8 days, however, the difference was not statistically significant. The results of this study indicate that TIT seems to be a major factor relating to delayed graft function in cadaveric renal transplantation.  相似文献   
87.
A 74-year-old woman suffered from progressive muscle atrophy and weakness of her arms since she was seventy two years old. Before referral to our department, she was diagnosed as having cervical spondylotic myeloradiculopathy and received spinal fusion. Though spinal decompression was successful, muscle weakness of her upper limbs were progressive even after the surgery. On admission, neurological examinations revealed marked atrophy and weakness of her bilateral upper limbs with absent deep tendon reflexes showing man-in-the-barrel syndrome. Her lower extremities had normal muscle strength, but fasciculations were seen in her all four limbs. Electrophysiologically, motor nerve conduction velocity was almost normal but the amplitude was remarkably decreased, conduction block was not detected, and electromyography showed neurogenic patterns on her all extremities. Spinal progressive musclar atrophy (SPMA) accompanied with Sj?gren's syndrome was the likely diagnosis. Because 50 kDa anti-neuronal antibodies were found in her serum, we assumed that anterior horn cells were impaired by an autoimmune mechanism. Thus we treated her with corticosteroid pulse therapy, plasma exchange (PE) and intravenous immunoglobulin infusion therapy (IVIG). Although steroid pulse therapy only had a minimal effect, PE and IVIG promoted a remarkable improvement on her weakness, and the effect lasted for about three months. This is the first case of SPMA with Sj?gren's syndrome which showed good response to PE and IVIG in the early course of the disease. We considered that some SPMA-like motor neuron syndrome accompanied with autoimmune features may require immunomodulating therapies.  相似文献   
88.
Background Cat cry syndrome is an autosomal disease accompanying abnormal deletion of chromosome 5 and occurs in only 1 of 50,000 neonates. Scoliosis has been reported as a skeletal complication in cat cry syndrome. The characteristics and causes of scoliosis in this rare syndrome are unknown. The purpose of this study was to present the characteristics of scoliosis in cat cry syndrome and to speculate on its causative mechanisms. Methods We report on 11 cases (5 boys and 6 girls) of cat cry syndrome. Detailed investigations of scoliosis, as well as physical and imaging examinations, were performed to characterize scoliosis and its causes. Average age at initial diagnosis of scoliosis was 4.3 years, and average age at final examination was 11.8 years. Results The incidence of scoliosis was as high as 73% (8/11). Most cases show a single right thoracic curve. Of the 8 patients with scoliosis, 3 patients who had increased muscular tone showed marked progression of scoliosis with growth. Conclusions Muscular hypertonia may play a key role in the progression of scoliosis in cat cry syndrome.  相似文献   
89.
Pharmacological properties of 5-(3-((2-(3,4-dimethoxyphenyl)ethyl)-amino)-1- oxopropyl)-2,3,4,5-tetrahydro-1,5-benzothiazepine fumarate (KT-362), a newly synthesized calcium release blocker, were studied by comparing its vascular selectivity and cardiovascular actions with those of verapamil, a calcium entry blocker. The relaxing effect of KT-362 in rabbit femoral and basilar artery strips contracted with norepinephrine was greater than that in aortic and coronary artery strips. In anesthetized mongrel dogs, KT-362 (0.1-3.0 mg/kg, i.v.) decreased the mean blood pressure, heart rate and total peripheral resistance in a dose-dependent manner, while cardiac output increased slightly despite a decrease in left ventricular pressure. This is consistent with the data on verapamil. Both i.a. and i.v. injections of KT-362 produced a marked dose-dependent increase in vertebral and femoral blood flow. Pretreatment of atropine, propranolol or diphenhydramine exerted no significant effect on the KT-362-induced vasodilation. Verapamil caused a marked increase in the vertebral and coronary blood flows after the injections, but only a slight increase in femoral blood flow. KT-362 at the dose of 10 mg/kg, i.v., had no significant effect on the PQ interval on the electrocardiogram in anesthetized dogs, but 0.1 mg/kg of verapamil increased this interval significantly. These results suggest that KT-362 has properties similar to calcium entry blockers such as verapamil on systemic hemodynamic actions except for the reactivity of vasculatures.  相似文献   
90.
BACKGROUND: There have been few multicenter studies using intravascular ultrasound (IVUS) to assess the process of atherosclerosis in a Japanese population with hypercholesterolemia that is being treated with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors for control of low-density lipoprotein-cholesterol. METHODS AND RESULTS: An open-label multicenter study is planned to evaluate with IVUS whether treatment with rosuvastatin for 76 weeks results in regression of coronary artery atheroma volume in patients who have coronary heart disease (CHD) and hypercholesterolemia. Sample size is 200 subjects with CHD who are to undergo percutaneous coronary intervention. The planned duration is between October 2005 and October 2008. CONCLUSIONS: The COSMOS study will be the first multicenter cardiovascular study in a Japanese population and may provide new evidence on the effects of rosuvastatin on the progression of coronary atherosclerotic lesions.  相似文献   
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