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BACKGROUND: The major aldosterone metabolite 3 alpha,5 beta tetrahydroaldosterone reflects up to 45% of the aldosterone secretion. Its 24-h urinary excretion is likely to provide an accurate index of the daily aldosterone production and to be an indicator for primary aldosteronism (PA). METHODS: In a prospective study, the validity of tetrahydroaldosterone as a screening test for PA was evaluated in comparison to serum potassium, plasma aldosterone, plasma renin activity, plasma aldosterone/renin activity ratio (PARR), as well as 24-h urinary aldosterone-18-glucuronide and free aldosterone. A total of 111 normotensive individuals, 412 PA patients and 1453 essential hypertensive patients, were studied. The effect of blood sampling technique on potassium level was also investigated. RESULTS: Tetrahydroaldosterone differentiated PA from essential hypertension with a sensitivity of 96% and a specificity of 95%. The sensitivity was 89% for plasma aldosterone, 87% for free aldosterone, 85% for PARR, 71% for aldosterone-18-glucuronide and 51% for renin activity. Specificities varied between 91% and 85%. The combined use of the parameters plasma aldosterone > or =9.0 ng/dL and PARR > or =25 resulted in a sensitivity of 82% and specificity of 95%. Forearm exercise proved to be a source of erroneous elevations of potassium sufficient to obscure the suspicion of PA. CONCLUSION: The data suggest that tetrahydroaldosterone is the most reliable screening test for PA. Tetrahydroaldosterone determination in combination with aldosterone-18-glucuronide and free aldosterone increases diagnostic specificity for PA. Potassium, renin, plasma aldosterone, and basal PARR are inadequate screening procedures because they are subject to high rates of false-positive and false-negative results.  相似文献   
23.
Reoccurrence of ischemic events several months after a percutaneous transcutaneous coronary angioplasty is usually due to a restenosis. Coronary angiography rarely shows a new stenosis on another site or on the left main coronary artery. In this series, we report 5 cases of left main coronary artery stenosis which have occurred from 3 to 12 months after a prior percutaneous angioplasty. This phenomenon which has previously been described after direct cannulation of the coronaries ostia during aortic valve replacement in the 70'. This complication is related to intimal damage caused by traumatic manipulation of the left main, which can be either already minimally altered or normal. This complication is rare after percutaneous transcutaneous coronary angioplasty (0.2-1.7%) according to various series. We compare our cases to the published cases in the literature.  相似文献   
24.
All tobacco smokers should be identified and provided with a smoking cessation intervention (SCI) during tuberculosis (TB) treatment. To ensure that this occurs, the intervention process should be recorded and monitored. Monitoring is the best guarantee that care is standardised and offered equitably to all patients. It allows for evaluation of processes and outcomes so that population needs can be identified and appropriate techniques added or updated. In this article we propose steps for brief intervention as a part of the monitoring process, using model forms and suggested procedures for filling them in. The suggested forms are a modified TB treatment card that includes information about tobacco use, an SCI patient card to be added to the patient's TB treatment folder, SCI registers and SCI quarterly report forms and a tobacco use questionnaire for evaluation of services.  相似文献   
25.
The present study assessed 106 diabetic patients 2 years after beginning insulin treatment at or after 70 years of age. Ten patients (9%) had had the therapy discontinued after 2-4 months, 26 (25%) had died of causes unrelated to insulin therapy, 12 (11%) were lost to follow-up, and 58 (55%) were still alive and insulin treated. Fifty-one were at home and seven institutionalized for reasons unrelated to insulin therapy. Of these 58 patients, 50 were available for further study. Except for frequency of travel, which had decreased, lifestyle either improved or did not change. Patients' perceptions of the goals of treatment were more appropriate to a younger population of patients, who are less vulnerable to hypoglycaemic reactions. Mean fasting blood glucose was considered by the medical staff to be too low in 42% of cases. Adding insulin to the treatment of the elderly did not negatively affect their lifestyle, and indeed, insulin therapy appeared to create or strengthen the patients' existing social support network. Educational interventions must attempt to extend the effect of the specialized unit outside the hospital, to families, visiting nurses as well as general practitioners.  相似文献   
26.
Somatostatin receptors on lactotroph cells of the anterior pituitary are positively regulated by estradiol. In the present work, we investigated whether estradiol regulation of somatostatin receptors also occurred in the female rat brain. 125I-Tyr0-DTrp8-somatostatin (125I-SRIF: 780 Ci/mM) was used as a ligand. Female adult rats were ovariectomized and treated or not with estradiol benzoate (20 micrograms/day for 1 or 8 days). In female brains, 125I-SRIF binding, as assessed by film radioautography, was high in the basolateral amygdala, CA1 field and dentate gyrus of the hippocampus and locus coeruleus, moderate in the median habenula and deep layers all through the cortex. Castration or estradiol treatment did not modify 125I-SRIF binding in these regions. By light-microscopic radioautography, a subpopulation of 125I-SRIF-labeled cells was localized in the ventrolateral portion of the arcuate nucleus. Ovariectomy alone did not significantly affect the number and binding density of 125I-SRIF-labeled cells in the arcuate nucleus. However, estradiol treatment in ovariectomized animals significantly increased both parameters. Along the estrus cycle, the number of 125I-SRIF-labeled cells was not significantly modified but 125I-SRIF binding density was significantly higher in proestrus as compared to diestrus I, diestrus II and estrus. These results demonstrate that brain 125I-SRIF binding sites are positively regulated by estradiol only in the arcuate nucleus of the hypothalamus.  相似文献   
27.
The objective of this study was to evaluate the switch to once‐daily darunavir/ritonavir 800/100 mg in treatment‐experienced patients with suppressed HIV‐1 replication on a twice‐daily ritonavir‐boosted protease‐inhibitor (bid PI/r) containing regimen, that is in a setting where genotypic resistance test cannot be performed. In this open label, non‐comparative, multicenter study, patients on a bid PI/r‐containing triple combination, with suppressed viral replication, were switched to once‐daily darunavir/r 800/100 mg containing triple combination. The primary endpoint was the proportion of patients with plasma HIV‐RNA < 50 copies/ml 24 weeks after the switch. Intensive darunavir pharmacokinetic evaluation was performed at Week 4 (W4) in 11 patients. Eighty‐five patients were enrolled. All had HIV‐RNA < 50 copies/ml at screening with a pre‐exposure to a median of 2 PI/r (1–5). By intent‐to‐treat analysis (missing = failure), 78/85 patients (92%, 95% CI [83;96]) maintained an HIV‐RNA < 50 copies/ml at W24. Seven patients experienced protocol‐defined treatment failure between baseline and W24: Two had confirmed low‐level viral rebound, one discontinued study treatment for adverse event, three withdrew their consent, and one was lost to follow‐up. By on‐treatment analysis, 78/80 patients (97%, 95% CI [91;99]) maintained an HIV‐RNA < 50 copies/ml at W24. Results were similar at Week 48. The median area under the darunavir plasma concentration–time curve measured in 11 patients was 61,380 ng hr/ml; darunavir median trough concentration 1,340 ng/ml and darunavir half‐life was 12.2 hr. Tolerability of once‐daily darunavir/r 800/100 mg was excellent. Optimally suppressed, treatment‐experienced patients can switch safely from a twice‐daily PI/r regimen to a once‐daily darunavir/r 800/100 mg containing regimen. J. Med. Virol. 85:8–15, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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29.
To study if self-monitoring of glucose, urinary or capillary, could help them to improve their metabolic control through better compliance to diet and/or hypoglycaemic agents, 208 non-insulin-treated poorly controlled diabetic patients were randomized to: group A--regular HbA1c determinations but no self-monitoring, group B--self-urine glucose monitoring, twice every other day, group C--self blood glucose monitoring, twice every other day, and followed six months. At the end of the study period, the decrease of HbA1c over six months--main endpoint--was not significantly different between the three groups (mean +/- SEM; group A: -0.5 +/- 0.2%; group B: -0.1 +/- 0.3%; group C: -0.4 +/- 0.3%). However, the degree of compliance to blood glucose self-monitoring in group C appeared to relate to the outcome: a significant correlation was found between the number of blood glucose strips used and the decrease of HbA1c (r = .36, p less than .02). We conclude that regular self-monitoring has no definite advantage over the usual management for improving metabolic control in non-insulin-treated diabetic patients, though it may possibly help patients ready to comply with its use.  相似文献   
30.
Of 495 patients reported in a large urban histoplasmosis outbreak, we studied 276 whose serologic tests were done in a single laboratory. Serologic test results were positive in 96% of these patients (compared with less than 5% of controls from an endemic area), cultures were positive in 22%, and special stains in 19%. The immunodiffusion test results were negative in 13% of patients who had positive findings by complement fixation, and 1% had positive results only by immunodiffusion. The complement fixation test was almost twice as sensitive as the immunodiffusion test in patients with subclinical infection. The serologic response differed significantly among the clinical syndromes with higher titers in cavitary and lower titers in disseminated disease. Factors associated with titers of 1:64 or greater to both antigens were black race and immunocompetence. High mycelial titers were also associated with more intense exposure, and high yeast titers were associated with age less than 36 years. No prognostic significance could be proved for fourfold titer rises or falls or persistence of precipitins.  相似文献   
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