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991.
The effect of selectively decreasing renal angiotensin II type 1 (AT1) receptor expression on renal function and blood pressure has not been determined. Therefore, we studied the consequences of selective renal inhibition of AT1 receptor expression in normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) in vivo. Vehicle, AT1 receptor antisense oligodeoxynucleotides (AS-ODN), or scrambled oligodeoxynucleotides were infused chronically into the cortex of the remaining kidney of conscious, uninephrectomized WKY and SHR on a 4% NaCl intake. Basal renal cortical membrane AT1 receptor protein was greater in SHR than in WKY. In WKY and SHR, AS-ODN decreased renal but not cardiac AT1 receptors. AT1 receptor AS-ODN treatment increased plasma renin activity to a greater extent in WKY than in SHR. However, plasma angiotensin II and aldosterone were increased by AS-ODN to a similar degree in both rat strains. In SHR, sodium excretion was increased and sodium balance was decreased by AS-ODN but had only a transient ameliorating effect on blood pressure. Urinary protein and glomerular sclerosis were markedly reduced by AS-ODN-treated SHR. In WKY, AS-ODN had no effect on sodium excretion, blood pressure, or renal histology but also modestly decreased proteinuria. The major consequence of decreasing renal AT1 receptor protein in the SHR is a decrease in proteinuria, probably as a result of the amelioration in glomerular pathology but independent of systemic blood pressure and circulating angiotensin II levels.  相似文献   
992.
A 50-year-old male with left cervical lymphadenopathy visited our hospital. Infectious and lymphomatous diseases were suspected in the patient. Since the patient owned a dog, which often licked the patient's face, Bartonella infection was also suspected. Histopathological examination in the lymph node biopsy revealed the epithelioid granuloma, but B. henselae was not detected from the culture of the lymphnode. B. henselae DNA also was not detected from the lymph node. Since the antibody titer (lgG) to B. henselae showed 1:128 by immunofluorescent antibody technique (IFA), he was serdogicalg diagnosed as cat-scratch disease. 'Cat-scratch disease' is named after cat scratch, however we propose 'B. henselae infection' which is more appropriate since other animals could serve as a cause of infection.  相似文献   
993.
We determined intima-media thickness (IMT) and diameter of carotid artery and estimated their correlations with cardiovascular risk factors in 1129 men aged 60-74 years, who participated in a cardiovascular risk survey in three Japanese communities. The multivariate odds ratios (95% confidence interval) for the maximum IMT > or = 1.1 mm in the common carotid artery (CCA) were 1.3 (1.1-1.5) per 4 years of age, 1.8 (1.4-2.5) for hypertension, 1.4 (1.2-1.7) for a 34.4 mg/dl increase in serum total cholesterol, 0.7 (0.6-0.8) for a 14.7 mg/dl increase in serum HDL-cholesterol, and 2.4 (1.1-5.0) for history of stroke, while the maximum IMT > or = 1.5mm in the internal carotid artery (ICA) were 1.6 (1.4-1.8) per 4 years of age, 1.9 (1.5-2.4) for hypertension, 1.6 (1.2-2.1) for current smoking, and 3.5 (1.6-7.6) for history of stroke. Age, height, hypertension, current smoking, ethanol intake and history of coronary heart disease were independent determinants of both the outer and inner CCA diameter. Maximum IMT correlated positively with the outer diameter and inversely with the inner diameter in the CCA. Carotid atherosclerosis suggests to be a risk factor for stroke among Japanese elderly men, although future prospective studies are required to confirm this finding.  相似文献   
994.
Sato M  Saito Y  Endo C  Sakurada A  Feller-Kopman D  Ernst A  Kondo T 《Chest》2004,126(1):108-113
OBJECTIVE: An overdiagnosis bias occurs with the diagnosis of a disease that does not produce signs or symptoms before the patient dies from other causes. We sought to determine whether overdiagnosis bias is a factor when screening for squamous cell carcinoma of the lung. DESIGN: Retrospective study of the Miyagi Population-Based Lung Cancer Screening Registry for high-risk patients who were seen between January 1, 1982 (when sputum cytology tests were added for men with long smoking histories), and December 31, 1996. SETTING: Miyagi Prefecture, Japan. PATIENTS: A total of 251 patients (all men) who had sputum cytology test results that were positive for squamous cell carcinoma but had normal radiograph findings, 44 of whom declined cancer treatment (mean age, 70 years) and 207 of whom were treated with resection within 12 weeks of diagnosis (mean age, 65.5 year). END POINTS: Five-year and 10-year survival rates from primary lung cancer in both groups as of August 15, 2001. RESULTS: Among the 44 untreated patients, 15 (34%) remained asymptomatic. The survival rate due to primary lung cancer death in the untreated group was 53.2% at 5 years and 33.5% at 10 years. The survival rate among treated patients was 96.7% at 5 years and 94.9% at 10 years. Of the 125 treated patients who died, 14 (11.2%) died from primary lung cancer. CONCLUSION: Given that the two thirds of the untreated patients with squamous cell carcinoma of the bronchus died from lung cancer within 10 years, overdiagnosis bias does not appear to be a factor in screening for this disease. Thus, we recommend that patients with radiographically occult squamous cell carcinoma of the bronchus undergo tumor treatment after localization.  相似文献   
995.
996.
The level of circulating endotoxin was determined in the sera from children hospitalized for treatment of diarrhea at the International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh. A significant level of endotoxin was detected in the sera from 23 (54%) of 42 children. On the other hand, in 32 normal controls, endotoxin was below the limits of detection of the assay. Antibiotic and fluid therapy markedly reduced the level of serum endotoxin and improved the general condition of most patients. Non-survivors (n = 5) had higher levels of circulating endotoxin before treatment than survivors (n = 37), suggesting a significant correlation between the serum endotoxin level before treatment and mortality. Malnutrition did not affect the serum endotoxin level in the patients with diarrhea. It was suggested that infection of Gram-negative bacteria might be involved in a significant number of patients with diarrhea in Bangladesh and that endotoxin might play a pathogenic role in those patients.  相似文献   
997.
BACKGROUND: The relationship between enhanced myocardial oxidative stress and impaired beta-adrenergic signaling remains to be characterized during the development of dilated cardiomyopathy. METHODS AND RESULTS: Alterations in myocardial oxidative stress and beta-adrenergic signaling, as well as left ventricular (LV) functional and structural changes, were evaluated during the development of cardiomyopathy in TO-2 hamsters; F1B hamsters served as controls. LV dysfunction was first apparent at 8 weeks of age and deteriorated thereafter in the TO-2 hamsters. At 32 weeks, the animals exhibited heart failure with an increased plasma norepinephrine concentration. Cardiac myolysis, as demonstrated by elevated plasma concentration of cardiac troponin T, peaked at 8 weeks. The glutathione redox ratio revealed increased oxidative stress in the LV myocardium in TO-2 hamsters even at 4 weeks and became manifest after 8 weeks. The hearts of TO-2 hamsters had significantly reduced superoxide dismutase activity from 8 weeks onward compared with control hamsters. However, glutathione peroxidase activity was unchanged at any time point. The LV functional response to isoproterenol was markedly reduced at 8 weeks, without any apparent changes in the amount of beta-adrenergic signaling molecules, and it deteriorated thereafter. Adenylyl cyclase activity was significantly decreased, despite increased amounts of both G(s) alpha mRNA and protein, in the LV myocardium at 18 weeks. CONCLUSIONS: Myocardial oxidative stress is actually enhanced in the initial development of LV dysfunction. Both activation of myocardial oxidative stress and impairment of beta-adrenergic signaling become prominent at the stage of severe LV dysfunction. Myocardial oxidative stress may be involved in the development of beta-adrenergic desensitization.  相似文献   
998.
The present study was designed to develop a method to continuously measure Holter electrocardiogram (ECG) and physical activity in terms of metabolic costs to examine circadian dynamics of RR intervals and physical activity in patients with heart failure. A total of 7 healthy subjects and 3 heart failure patients performed cardiopulmonary exercise test using four-stage graded treadmill walking at 0% grade to examine whether the acceleration signals in the vertical direction could reflect actual body energy expenditure during physical activity. Then, using this new method, 24-hr monitorings of ECG and physical activity were performed in 24 inpatients with heart failure while they were allowed to walk around freely. Our results showed the integral of rectified acceleration signals was closely correlated with actual metabolic cost in all subjects. Instantaneous changes in heart rate were quite concordant with physical activity. As compared with the asymptomatic patients (n = 12), the symptomatic patients (n = 12) had lower energy expenditure during 8-hr daytime periods but higher mean heart rate. Furthermore, a more prominent ultradian rhythm of circadian changes in heart rate and physical activity was found in 50% of all subjects studied. The simultaneous analysis of Holter ECG and physical activity as the same time series revealed that in patients with heart failure, sympathovagal balance shifted toward sympathotonic conditions and their physical activity could become subject to intrinsic ultradian dynamics of body's homeostasis.  相似文献   
999.

Background/Purpose

Between 1988 and 2003, 38 patients underwent biliary resection for pancreaticobiliary maljunction (PBM). We reviewed the histopathologic findings for the surgically resected specimens to compare the clinical and pathologic features and assess the relationship between changes in the background biliary epithelium and the development of neoplasms.

Methods

Papillary hyperplasia (PHP) seen in the biliary epithelium of patients with PBM, was classified into grades 0–III in the gallbladder and grades 0–II in the extrahepatic bile duct, according to the extent, and was assessed for links with tumors in the same specimens.

Results

The incidence of gallbladder carcinoma was 13/21 in grades I–II, versus 0/16 in grade III, while the incidence of bile duct carcinoma was 4/20 in grade I versus 0/5 in grade II. Furthermore, these incidences for patients below age 50 years and age 50 or older were 1/18 versus 12/20, and 0/14 versus 6/17, respectively.

Conclusions

PHP of the biliary epithelium in PBM patients is an important precursor lesion, especially for gallbladder cancer, and the risk becomes greater with age, regardless of the type of pancreatobiliary junction (PBJ) and its location in the biliary tract.  相似文献   
1000.
A 54-year-old woman was admitted to our hospital following the diagnosis of decompensated liver cirrhosis with hepatitis C. She underwent living-donor liver transplantation, performed using the left hepatic lobe with the middle hepatic vein donated by her husband. After the transplantation, the patient suffered from massive ascites with liver dysfunction. Computed tomography demonstrated stenosis of the suprahepatic inferior vena cava (IVC) with focal collection of fluid. A second laparotomy was performed 19 days after the transplantation. When the encapsulated localized ascites on both sides of the IVC was opened, the ascites was flushed away. Subsequently, the grafted liver was easily mobilized and it was placed in the natural position without any tension, and the pressure gradient of the IVC was improved. Herein, we report a very rare case of compression stenosis of the IVC resulting in Budd-Chiari syndrome caused by localized encapsulated ascites.  相似文献   
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