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991.
A rat model of hereditary renal carcinoma (RC) was found in a rat colony of the Sprague-Dawley strain in Japan and named the "Nihon" rat. In heterozygotes, RCs, predominantly the clear cell type, develop from early preneoplastic lesions, which began to appear as early as 3 weeks of age, to adenocarcinomas by the age of 6 months. The Nihon rat is an example of a Mendelian dominantly inherited predisposition for development of RCs like the Eker (Tsc2 gene mutant) rat. We have previously shown that the Nihon mutation was tightly linked to genes that are located on the distal part of rat chromosome 10. The order of the genes is the Eker (Tsc2 gene (human 16p13.3)-Il3 gene-Nihon gene-Llgl1 locus- Myhse gene. We now describe a germ-line mutation in the Birt-Hogg-Dubé gene (Bhd) (human 17p11.2) caused by the insertion of a single nucleotide in the Nihon rat, resulting in a frameshift and producing a stop codon 26 aa downstream. We found that the homozygous mutant condition was lethal at an early stage of fetal life in the rat. We detected a high frequency of loss of heterozygosity (LOH) in primary RCs (10/11) at the Bhd locus and found a point mutation (nonsense) in one LOH-negative case, fitting Knudson's "two-hit" model. The Nihon rat may therefore provide insights into a tumor-suppressor gene that is related to renal carcinogenesis and an animal model of human BHD syndrome.  相似文献   
992.
BACKGROUND: It is unclear whether early initiation of low-dose pravastatin therapy can reduce the occurrence of major adverse cardiac events after acute myocardial infarction (AMI). METHODS AND RESULTS: The study group comprised 353 patients with AMI who had plasma total cholesterol levels of 200-250 mg/dl and triglyceride levels <300 mg/dl. The patients were randomly assigned to either receive pravastatin (10 mg/daily, n=176) or not (n=177). The primary endpoint was a composite of death, nonfatal myocardial infarction (MI), unstable angina (UA), stroke, revascularization, and rehospitalization because of other cardiovascular disease. The follow-up period was 9 months. The primary endpoint occurred in 31 patients (17.9%) in the pravastatin group and 55 patients (31.4%) in the non-pravastatin group (relative risk, 0.56; 95% confidence interval, 0.36-0.87). There were no significant differences in the risk of death, nonfatal MI, UA, and stroke between the 2 groups, although the pravastatin group had a lower risk of need for revascularization. CONCLUSION: For patients with AMI, early and low-dose pravastatin therapy (10 mg/daily) reduces recurrent major adverse cardiac events, mostly the requirement for revascularization.  相似文献   
993.

Aims

Continuous glucose monitoring (CGM) is not available for all patients with type 2 diabetes (T2D) at risk of nocturnal hypoglycemia (NH). This study was performed to predict the lowest nocturnal blood glucose (LNBG) levels.

Methods

An LNBG prediction formula was developed by multivariate analysis using the data including self-monitoring of blood glucose from a formula making (FM) group of 29 insulin-treated T2D patients with CGM. The validity of the formula was assessed by nonparametric regression analysis of actual and predicted values in a formula validation group consisting of 21 other insulin-treated patients. The clinical impact on prediction was evaluated using a Parkes error grid.

Results

In the FM group with a median age of 64.0, the following formula was established: Predicted LNBG (mg/dL)?=?127.4–0.836?×?Age (y)?+?0.119?×?Self-monitored fasting blood glucose (mg/dL)?+?0.717?×?Basal insulin dose (U/day) (standard error of calibration 17.2?mg/dL). Based on the validation results, standard error of prediction was 31.0?mg/dL. All predicted values fell within zones A (no effect on clinical action) and B (little or no effect on clinical outcome) on the grid.

Conclusions

LNBG could be predicted, and may be helpful for NH prevention.  相似文献   
994.
Expression of muscarinic receptor genes in the human coronary artery   总被引:1,自引:0,他引:1  
Niihashi M  Esumi M  Kusumi Y  Sato Y  Sakurai I 《Angiology》2000,51(4):295-300
  相似文献   
995.
Summary The hemodynamic and clinical effects of OPC-8212, a newly synthesized, orally effective inotropic agent, were assessed for the first time in ten patients with severe congestive heart failure by means of right heart catheterization with a Swan-Ganz catheter. Cardiac output was determined by the thermodilution technique. Patients received a single oral dose of 6 mg/kg. To determine the magnitude and time-course of the effects of OPC-8212, measurements were made during an observation period before and 2, 4, 8, and 12 h after administration. Blood was also taken at these times for measurement of the concentration of plasma OPC-8212. No large meals were allowed during the first 4 h. After the single oral dose of OPC-8212, plasma concentrations increased rapidly, reaching an effective level after 8 h and peaking at 12 h. Hemodynamic performance improved as the mean OPC-8212 plasma level increased, with the maximum effect being observed between 8 and 12 h after acute administration of the drug. At 8 h, the cardiac index was increased from the baseline value of 2.4±0.2 (SEM) to 2.8±0.3 l/min/m2 (P<0.01). The stroke work index rose from 26.2±5.1 to 31.7±60 g · m/m2. The excessive pulmonary artery diastolic pressure fell from 22±2 to 17±3 mmHg at 8 h (P<0.001) and to 16±2 mmHg (P<0.001) at 12 h. The incidence of ventricular premature beats was not increased and no other side effects were observed. These changes were not associated with significant changes in heart rate or systolic blood pressure. Thus, this drug appears to be very promising for the long-term treatment of congestive heart failure.  相似文献   
996.
The effect of green tea on iron absorption from tablets containing sodium ferrous citrate was investigated in four elderly patients with iron deficiency anemia and in eleven normal elderly subjects. In both groups, the serum iron level reached a maximum value from 2 to 4 hours after taking iron tablets and returned to the baseline value after 24 hours. No inhibitory effect of green tea on iron absorption was recognized.  相似文献   
997.
Endoscopic mucosal resection   总被引:14,自引:0,他引:14  
  相似文献   
998.
999.
1000.
The effects of sodium intake on blood pressure and platelet function were evaluated in 19 subjects with essential hypertension (10 men and 9 women; mean age 49.7 years). The study was conducted under 3 conditions: (1) normal sodium diet (12 g/day of salt was used in cooking), (2) after 5 days of mild sodium restriction diet (6 g/day of salt was used in cooking) and (3) after moderate sodium restriction (no salt was used in cooking). Blood pressure was significantly reduced following sodium restriction without any change in heart rate. The ratio of the plasma level of beta-thromboglobulin to platelet factor IV, regarded as the most reliable index for platelet activation in vivo, increased significantly after mild sodium restriction; this change was maintained after moderate sodium restriction. Plasma thromboxane B2, a stable metabolite of thromboxane A2, increased significantly after sodium restriction; the level of 6-ketoprostaglandin F1 alpha, a stable metabolite of prostacyclin, was unaffected. These results indicate that dietary sodium restriction induces both a reduction of blood pressure and an activation of platelet function in vivo. Thus, one must consider both antihypertensive effects and effects on platelet function as factors in adjusting the dietary sodium intake in the course of antihypertensive therapy.  相似文献   
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