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991.
Is High Job Strain Associated With Hypertension Genesis?   总被引:2,自引:0,他引:2  
BACKGROUND: The aim of this analysis was to test, in a large sample of normotensive subjects, the short-term influence of job strain on the onset of hypertension. METHODS: According to the questionnaire of Karasek et al, job strain was divided into four modalities: (high strain, low strain, passive, and active) based on job demand (eg, the need to work hard and quickly) and job latitude (eg, control over skill use, time allocation, and organizational decisions) scores. High strain (HS) was defined by a high demand and a low job decision latitude. Individual data obtained in 926 (age 41 +/- 6 years) healthy normotensive or newly diagnosed hypertensive subjects were analyzed. Subjects participated in two prospective work site surveys designed to assess the influence of job strain on hypertension development. Relationships between job strain modalities and work site blood pressure (BP) levels were assessed using a general linear model. A complementary analysis using the the Pearson Phi coefficient (Z analysis) was implemented to explore nonlinear or scattered relationships between job strain and onset of hypertension. RESULTS: Systolic BP (SBP) was linearly related significantly to BMI and alcohol consumption, whereas diastolic BP (DBP) was related to age. The linear model did not find any relationship between SBP or DBP and job strain modalities. Using the Z analysis, development of systolic hypertension (SBP >140 mm Hg) was significantly associated with high job strain (P < .001). CONCLUSIONS: Our results suggest that there is no global relationship between job strain and BP levels. However our methodology revealed a significant association between job strain and work site BP in a predominantly male subgroup of newly diagnosed hypertensive subjects exposed to high job strain.  相似文献   
992.
OBJECTIVES: The aim of this retrospective study was to assess the long term results of long-lasting endoscopic stenting for benign biliary strictures related to laparoscopic cholecystectomy. Additional biological and morphological data were collected from these patients during follow-up. METHODS: Patients undergoing ERCP for post-laparoscopic cholecystectomy biliary stricture in one of the three participating centers between 1990 and December 2001 were identified. Only patients with successful endoscopic stenting were subsequently included and analyzed. Follow-up data were obtained from referring centers, general practitioners and patients or relatives. Hepatic blood tests and abdominal ultrasound were proposed to all the patients who had not undergone further treatments after stent removal. RESULTS: Eight-eight patients had undergone ERCP for benign biliary stricture related to laparoscopic cholecystectomy. Stenting failed in 19 patients. Balloon dilatation alone was used in four patients. Strictures were successfully stented in 65 patients. The mean number of stents inserted at the same time was 1.6. The mean duration of stenting was 14 months (range 1-120 months). Eighteen patients (28%) developed biliary or pancreatic symptoms during stenting. ERCP was considered satisfactory at the end of stenting (i.e. no remaining stricture or minor remaining change on ERCP) in 45 patients (69%). Twenty-two patients were lost to follow-up. Twenty-nine out of forty-three patients (67%) remained symptom-free with normal updated blood tests and abdominal ultrasound during a mean follow-up of 28 months (range 12-117 months) after stent removal. None of the patients with a normal ERCP at the end of stenting developed stricture recurrence during follow-up. Eleven patients were operated (8 with persistence of stricture, 2 for stricture recurrence up to 63 months after stent removal, 1 for pancreatitis). CONCLUSION: Based on clinical, morphological and biological criteria, a long-term success was obtained in 70% of patients with post-laparoscopic cholecystectomy benign biliary strictures, after several months of endoscopic stenting.  相似文献   
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CONTEXT: Prevalence of masked hypertension (MH) is far from negligible reaching 40% in some studies. The SHEAF study (Self measurement of blood pressure at Home in the Elderly: Assessment and Follow-Up) and others clearly showed that masked hypertension (MH) as detected by home blood pressure measurement (HBPM) is associated with poor cardiovascular prognosis. OBJECTIVE: Systematic HBPM to detect MH is not yet routine. The aim of this work is to better define the clinical profile of masked hypertensives within a population with controlled office blood pressure (BP) and the factors associated with a higher prevalence of MH. MATERIALS AND METHODS: BP was measured at the clinic by the doctor and at home by the patient himself. Risk factors for MH were analysed in a cohort of 1150 treated hypertensive patients over the age of 60 (mean age 70 +/- 6.5, 48.9% men) with controlled office BP. (SBP < 140 mmHg and DBP < 90 mmHg). RESULTS: 463 patients (40%) were masked hypertensives (SBP > or = 135 mmHg or DBP > or = 85 mmHg at home). Three parameters were associated with MH (odds ratio OR): office SBP (OR = 1.110), male gender (OR = 2.214) and age (OR = 1.031). Decision trees showed a 130 mmHg SBP was an efficient threshold to propose HBPM with a higher probability to detect MH. Subsequent variables were male gender and age over 70 in males. CONCLUSION: To detect masked hypertension, it would be logical to first of all select patients whose office SBP is between 130 and 140 mmHg.  相似文献   
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A 1H Nuclear Magnetic Resonance (NMR) spectroscopic investigation of the effects of single doses of four model hepatotoxins on male Sprague–Dawley rats showed that hypertyrosinemia was induced by three of the treatments (ethionine 300 mg/kg, galactosamine hydrochloride 800 mg/kg and isoniazid 400 mg/kg) but not by the fourth (thioacetamide 200 mg/kg). Concomitant histopathological and clinical chemistry analyses showed that hypertyrosinemia could occur with or without substantial hepatic damage and that substantial hepatic damage could occur without hypertyrosinemia. However, in the rats dosed with galactosamine hydrochloride, which showed highly variable amounts of liver damage at ca. 24 h after dosing, a clear relationship was found between the degree of hypertyrosinemia and the extent of the hepatic necrosis induced. In line with the cause of clinically observed Type II Tyrosinemia, we consider that the critical event in the onset of hepatotoxin-induced hypertyrosinemia is likely to be a reduction in hepatic tyrosine aminotransferase (TAT) activity. We discuss mechanisms by which TAT activity could be lost with special consideration given to pyridoxal 5′-phosphate (P5P) depletion and to the inhibition of protein synthesis. This analysis may have implications for the interpretation of clinical measures of liver status such as Fischer’s ratio and the branched-chain tyrosine ratio (BTR).  相似文献   
999.
OBJECTIVE: The measurement of PSA serum levels is central to all early detection programs for prostate cancer. Although individual PSA values were known to fluctuate in the short and long term, the influence of insolation and seasons on PSA had not been addressed to date. To assert the relationship between total and free PSA and meteorological data in 8644 participants (55-70 years) in the French arm of the ERSPC study. METHODS: Blood sample was taken at the local laboratory after informed consent and frozen sera were sent for central testing of total and free PSA. PSA measurement was performed within 7 days on the Access 1.0 automat with Hybritech reagents. Monthly meteorological data -- insolation, daily temperatures and rain precipitations -- were obtained from the local branches of the National Meteorology Agency. RESULTS: Total PSA -- but not free PSA -- was correlated with insolation, that is the monthly accrual in hours of sunshine during which the intensity was higher than 120 Watt x m(-2) (r = 0.05 (95%CI: 0.03-0.07; p < 0.0001)) while no relationships were shown between insolation and percent-free PSA (free PSA divided by the total PSA). Interdependence between total PSA and insolation was also apparent with respect to the 3 ng/mL ERSPC cutoff for recommending biopsies (213.1 vs. 206.2 hours, p = 0.004). Such relationship was even more evident in summer when the tested participants more often had a PSA > 3 ng/mL (17.1% vs. 14.3%, p = 0.0006) than in the rest of the year, resulting in 23% more chances of being referred for biopsies (Odds ratio 1.23, 95%CI: 1.10-1.40). CONCLUSIONS: Total PSA was shown to be strongly associated with insolation and seasons while the percent-free PSA was not influenced.  相似文献   
1000.
The aim of this study was to assess in rats the effect of protein feeding on the: 1) distribution of endogenous glucose production (EGP) among gluconeogenic organs, and 2) repercussion on the insulin sensitivity of glucose metabolism. We used gene expression analyses, a combination of glucose tracer dilution and arteriovenous balance to quantify specific organ release, and hyperinsulinemic euglycemic clamps to assess EGP and glucose uptake. Protein feeding promoted a dramatic induction of the main regulatory gluconeogenic genes (glucose-6 phosphatase and phosphoenolpyruvate carboxykinase) in the kidney, but not in the liver. As a consequence, the kidney glucose release was markedly increased, compared with rats fed a normal starch diet. Protein feeding ameliorated the suppression of EGP by insulin and the sparing of glycogen storage in the liver but had no effect on glucose uptake. Combined with the previously reported induction of gluconeogenesis in the small intestine, the present work strongly suggests that a redistribution of glucose production among gluconeogenic organs might occur upon protein feeding. This phenomenon is in keeping with the improvement of insulin sensitivity of EGP, most likely involving the hepatic site. These data shed a new light on the improvement of glucose tolerance, previously observed upon increasing the amount of protein in the diet, in type 2 diabetic patients.  相似文献   
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