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51.
To assess the pathophysiological role of atrial natriuretic factors in the regulation of blood pressure, we studied the effect of chronic infusion of a synthetic atrial natriuretic factor of 25 amino-acid residues on blood pressure and sodium-water excretion. Experimental subjects were rats with hypertension made by chronic infusion of vasopressin on regular intakes of sodium or on sodium loading with 1% NaCl as drinking water. When a subdepressor dose (150 micrograms/kg/day) of synthetic atrial natriuretic factor was delivered via an osmotic minipump into the jugular vein simultaneously with 7.2 U/kg/day of vasopressin infused intraperitoneally by another osmotic minipump, the expected elevation of systolic blood pressure was completely inhibited. This was not accompanied by any changes in urine volume and urinary sodium excretion. The antihypertensive effect was sustained throughout the experimental period lasting 3 days in rats on regular sodium intake (p less than 0.01) or on sodium loading with 1% NaCl as drinking water (p less than 0.01). These results indicate that a subdepressor dose of synthetic atrial natriuretic factor can modulate the vasopressor effect of vasopressin. Therefore it is suggested that an atrial natriuretic factor may be involved in the regulation of blood pressure via its antagonizing effect to vasopressin.  相似文献   
52.
CONTEXT: Health disparities between rural and urban communities are well documented. There are many suggested causes and many proposed solutions but no one-size-fits-all answer. The most successful community interventions have been introduced by communities themselves. However, before communities invest in such interventions, each group must identify and prioritize their needs. PURPOSE: This article describes the Hoshin facilitation method as a practical option assisting communities in assessing their needs and gaining consensus for future steps. METHODS: Thirty-four meetings were held in 11 rural communities in Hawaii using the Hoshin process to identify factors that impact rural health. Themes were identified by constant comparative analysis and thematic frequency described. Commonality of responses between communities was examined. Informal feedback was collected from meeting participants. FINDINGS: There was a great deal of commonality between community responses, with economic factors, drug use, lack of community leadership, lack of health care services and access to services, lack of healthy activities for youth, and poor public education being the most common issues noted. Group involvement in the meetings was high, and the facilitation method received positive feedback from participants. CONCLUSIONS: The Hoshin facilitation method is a very useful tool to help communities rapidly identify and prioritize areas for programmatic attention.  相似文献   
53.
OBJECTIVE AND DESIGN: JTE-607, a multiple cytokine inhibitor, was evaluated in lipopolysaccharide (LPS)-induced acute lung injury in rats in vivo and in vitro. MATERIALS AND METHODS: LPS instillation into airways of rats was performed. JTE-607 at 3-30 mg/kg and dexamethasone at 3 mg/kg were administered intravenously at 10 min and 0 min for JTE-607, and 60 min for dexamethasone prior to the LPS instillation (n = 8). Cytokine-induced neutrophil chemoattractant (CINC)-1 level and myeloperoxidase (MPO) activity in lung were measured at 4 h after LPS instillation, and at 24 h for lung wet weight measurement and histological study. LPS-induced CINC-1 production by rat alveolar macrophages were also measured in vitro. RESULTS: JTE-607 and dexamethasone showed a significant reduction of increased CINC-1 level and MPO activity in lung after LPS treatment in vivo. Increased wet weight was also significantly inhibited. Histological studies revealed that JTE-607 and dexamethasone significantly inhibited LPS-induced accumulation of peribronchial neutrophils and eosinophils, and perivascular edema. JTE-607 and dexamethasone suppressed CfNC-1 synthesis by rat alveolar macrophages in vitro with IC50 values of 12.4 microM and 2.3 nM, respectively. CONCLUSIONS: These results indicate that JTE-607 has an inhibitory effect on LPS-induced rat lung inflammation in parallel with CINC-1 reduction. The effect of JTE-607 was suggested to be through direct inhibition of CINC-1 production from rat alveolar macrophages. JTE-607 may thus be efficacious in cytokine-mediated lung inflammation such as acute respiratory distress syndrome.  相似文献   
54.
A study was made on the effect of detection wavelength and separation mode of HPLC on determination of urinary hippuric acid (HA) and three isomers of methylhippuric acid (MHA). The interference of other constituents of urine in the determination was effectively decreased by detection at a short wavelength of 227.6 nm. Meta and para MHAs were separated by the addition of beta-cyclodextrine to the mobile phase. Four metabolites were successfully separated from other components of urine by the combination of ODS-silica packed-column and mobile phase (method F). The detection limits were found to be 50 and 5 mg/l for HA and MHAs, respectively. MHAs could not be detected in the non-exposed subjects. Average levels (+/- SD) of HA in non-exposed males and females were 272.2 (+/- 210.8) and 393.0 (+/- 269.8) mg/l, respectively. The urinary levels of HA in females were significantly higher than those in males.  相似文献   
55.
We conducted a clinical study on respiratory infections complicating bronchial asthma. Transtracheal aspiration (TTA) was performed 37 times in 22 patients. The most frequently isolated organism was H. influenzae. The patients in whom organisms were isolated on TTA had a high incidence of fever and evidence of inflammation. Antimicrobial therapy caused a decrease in indices of inflammation (white blood cell count and ESR), but was less effective against the asthmatic symptoms. Respiratory infection may play a complex role in the clinical picture of bronchial asthma.  相似文献   
56.
The serum triglyceride concentration (TG) tested in health checks after meals cannot properly sort out hypertriglyceridemia with reference to the upper normal limit of fasting TG (150 mg/dl) set by the Japan Arteriosclerosis Society, because TG goes up considerably after a meal. In our survey of a large number of health check examinees (free of abnormal biochemical data other than TG and diseases under medical treatment), the mean (M) of fasting TG + 2 standard deviations (SD) was close to 150 mg/dl. When the screening level was set at M + 2SD for each time span after a meal, the ratio of the screened was distributed between 19.9 and 21.8%, which was close to 23.5%, the ratio of the screened on fasting. Accordingly, the nearest round number ending with zero for the first digit is suggested to be of practical use for the screening level of after-meal TG. The average TG in females was definitely lower than that of males, though proportionately increasing with age. The ratio of the screened among females aged between 20 and 49 was 5.3% on fasting and 3.2-5.8% for after-meal time spans, and that of the screened aged in their fifties was 11.3% and 8.2-12.9% respectively.  相似文献   
57.
58.
Crystal-matrix interrelations in brushite and uric acid calculi   总被引:1,自引:0,他引:1  
Brushite and uric acid calculi were studied by means of scanning electron microscopy with the partial dissolution method and transmission electron microscopy. Brushite calculi consist of radially oriented columnar crystals which have sheet-like substructure. The organic matrix is identified chiefly at the outside of the crystals but partly included between the substructure. The concentric matrix bands are often dislocated between the neighbouring crystals. Uric acid calculi also consist of radially oriented columnar crystals, and a fine meshwork of the organic matrix is incorporated within the crystals. The concentric matrix layers of different density are angled according to the crystal lattice. These findings indicate that the organic matrix arose from a mucinous surface coat, at least in the radially striated calculi. The crystals continued to grow in this gel-state milieu, either thrusting the matrix aside or incorporating it within the crystals.  相似文献   
59.
The aims of the present study were to observe the daily habituation to night sleep in a laboratory environment and to make clear the daily and individual sleep variations by using polygraph parameters, including electroencephalography (EEG). Sleep EEG records were obtained from a subject who slept ten successive nights, and from six subjects who each slept one night in the laboratory. The parameters used were as follows: sleep stage %, sleep latency (SL), REM latency (RL), number of stage shifts, subjective sleep, integral EMG, and slope (a) and intersect (b) of a regression equation used to estimate the sleep depth against sleep time. Stage WAKE and SL, slope (a), intersect (b) and the mean depth of sleep were found to become stable from the fifth night. Stage MT, the number of stage shifts, and integral EMG increased significantly from the fifth night and later, showing p less than 0.01, p less than 0.01, and p less than 0.05, respectively. Judging from these findings, the sleep habituation of the subject in the laboratory was completed within the first four nights. Coefficients of variation of sleep stage 2 and stage REM of the ten-nights' EEG were the lowest among all the sleep parameters examined. Almost all the parameters of day-to-day sleep of the subject who slept for ten successive nights in the laboratory showed smaller variations than those of the other six subjects. It may be concluded that the mist effect on sleep could be assessed more precisely by using an individual repeatedly than by using a group of subjects.  相似文献   
60.
Background: Pancreatic carcinoma is one of the most lethal cancers. Because pancreatic carcinoma is still very difficult to diagnose in its early stage, many of these patients will be considered unsuitable for surgery. If a cytological diagnosis is obtained at initial endoscopic retrograde cholangiopancreatography (ERCP), suitable treatment will be initiated without delay. Methods: To increase the number of exfoliated cells from the pancreatic duct, we devised a new technique, pancreatic duct lavage fluid (PDLF), following bronchoalveolar lavage fluid. The present paper reports the effectiveness of cytological examination using PDLF in the diagnosis of pancreatic carcinoma. We examined 18 pancreatic carcinoma cases. After the endoscopic retrograde pancreatography (ERP), PDLF was collected from a double‐lumen catheter inserted into the main pancreatic duct. Saline injected from the lumen for the injection, and PDLF was aspirated from the other lumen for the guidewire at the same time. The cytological examination was performed using PDLF. Results: Exfoliated cells were more frequently found in PDLF from all patients. In 15 cases (83%), cytological examination of PDLF revealed positive cytological results as the diagnosis of pancreatic carcinoma. Conclusion: Cytological examination using PDLF has a high sensitivity for detection of pancreatic carcinoma. The new examination, PDLF, is simple, safe and effective, so we expect PDLF to become widely popular.  相似文献   
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