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11.

Purpose

To define microwave ablation (MWA) charts according to time and power in human renal tumors and to compare them to the charts given by the HS AMICA manufacturer.

Materials and methods

A total of 54 patients with 54 renal cancers who underwent MWA were included. There were 36 men and 18 women with a mean age of 72.5 ± 10 [SD] years (range: 40–91 years). The system used for MWA was HS AMICA with the Amica-probe V4 applicator. The following variables (antero-posterior diameter, transverse diameter, cranio-caudal diameter and volume were measured on computed tomography examinations performed one month after MWA. The dimensions of the ablation zone were correlated with power (40 or 60 W) and exposure time (5, 10 and 15 min) used for MWA. Actual ablation dimensions were compared to the manufacturer's data.

Results

The variation of diameters, with a longer ablation time, was linear at 40 W with a volume increase of 30% for each additional 5 minutes. At 60 W, a more pronounced variation (volume increase of 112%) was observed. Compared to the manufacturer's chart, significantly larger ablation zones were obtained (P < 0.05), the differences being mainly marked for the antero-posterior diameter (≥ 1 cm).

Conclusion

MWA using AMICA generator produces reproducible ablation area for given time and power in renal tumor ablation. The charts presented here should be used instead of the manufacturer's chart, which is based on porcine liver and is significantly different.  相似文献   
12.
The effect of uremia on the binding of diazoxide to plasma proteins was studied. An equilibrium dialysis technique, using diazoxide-minus14C at approximately 30 and 300 mug/ml in the plasma phase, was used to measure diazoxide binding to plasma. Serum albumin concentration (Alb) and serum creatinine (Cr) or blood urea nitrogen (BUN) were negatively correlated. By single regression analysis, per cent free diazoxide (%FD) correlated negatively with Alb and positively with Cr or BUN. When %FD was regressed simultaneously against Alb and Cr or BUN, Alb emerged as the sole determinant of %FD (p less than 0.001), indicating that creatinine or BUN correlated with %FD by their inverse correlation to Alb rather than by an effect on drug protein binding. At the levels of Alb studied, %FD varied over a 2-fold range. In a retrospective study of the influence of uremia on diazoxide effect in hypertensive patients, a relatively low correlation (r, 0.59) was found between BUN and hypotensive effect. Prospective studies involving correlations of drug effect with renal function and %FD are required to assess the clinical importance of decreased binding of diazoxide to uremic plasma.  相似文献   
13.
Hypertension is a very common condition and the most important risk factor for the occurrence of cardiovascular events. The hyperactivity of the renin-angiotensin-aldosterone system is considered a cardiovascular risk factor in subjects with essential hypertension. The intrinsic vascular abnormality in which the renin-angiotensin-aldosterone system is clearly the milieu for the development of the pathologic changes in blood vessel walls is one of the causes of the establishment of hypertension. Many drugs with different mechanisms of action have been used for the treatment of hypertension and its vascular complications. Nevertheless, the utilities of many drugs are limited by their adverse effects. Continuous research in the search for new pharmacological agents for the treatment of hypertension has led to the development of angiotensin II receptor type AT1 blockers. The most important functions mediated by AT1 receptors include: vasoconstriction, induction of the production and release of aldosterone, renal reabsorption of sodium, cardiac cellular growth, proliferation of vascular smooth muscle, increase of peripheral noradrenergic action and the central activity of the sympathetic nervous system, stimulation of vasopressin release, and inhibition of renin release from the kidney. The angiotensin II receptor type AT1 blockers inhibit the interaction of angiotensin II with its AT1 receptor. These agents lower blood pressure without producing cough as a side effect since, unlike the angiotensin-converting enzyme inhibitors they do not influence the levels of bradykinin or substance P. Hence, these drugs are suitable for the treatment of hypertensive patients who require therapy with a drug blocking the effect of angiotensin-converting enzyme but cannot use angiotensin-converting enzyme inhibitors due to cough as a side effect.  相似文献   
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Graphene-related materials (GRMs) such as graphene quantum dots (GQDs), graphene oxide (GO), reduced graphene oxide (rGO), graphene nanoribbons (GNRs), and so forth have recently emerged as photovoltaic (PV) materials due to their nanodimensional structure and outstanding properties such as high electrical and thermal conductivity, large specific surface, and unique combination of mechanical strength and flexibility. They can be a crucial part of transparent electrodes, hole/electron transport materials, and active layers in organic solar cells (OSCs). Besides their role in charge extraction and transport, GRMs act as device protectors against environmental degradation through their compact bidimensional structure and offer good durability. This review briefly presents the synthesis methods of GRMs and describes the current progress in GRM-based OSCs. PV parameters (short circuit current, open circuit voltage, power conversion efficiency, and fill factor) are summarized and comparatively discussed for the different structures. The efficiency recently surpassed 15% for an OSC incorporating polymer-modified graphene as a transparent electrode. The long-term stability of OSCs incorporating GRMs is also discussed. Finally, conclusions and the outlook for future investigation into GRM-based devices for PVs are presented.  相似文献   
20.
Background: An adequate hydration status is critical to ensure efficiency during mental and physical activities.Our goal was to assess the hydration status of a Spanish group of aeronautical military men and to determine the association of hydration status with body composition and anxiety.Methods: A total of 188 men were evaluated through a validated hydration questionnaire, anthropometric and biochemical parameters, and an anxiety questionnaire. Based on these methods, the criteria of hydratio...  相似文献   
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