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991.
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Chronic kidney disease is accompanied by increased large-artery stiffness, but the relation between glomerular filtration rate within the reference range and central or peripheral arterial stiffness has been understudied. The link between renal function and arterial stiffness was assessed in 305 patients with never-treated essential hypertension (men: 58%; age: 48+/-11 years, blood pressure: 151/95+/-20/11 mm Hg), free from overt cardiovascular disease and with serum creatinine values <1.4 mg/dL (men) and <1.2 mg/dL (women), who underwent noninvasive aortic and upper-limb pulse wave velocity (PWV) determination. Aortic PWV was strongly related to age (r=0.55; P<0.001), whereas upper-limb PWV had a weaker nonlinear relation with age (beta=1.392; P<0.001 for age; beta=-1.312; P<0.001 for age squared) and a weak relation with aortic PWV (r=0.22; P<0.001). Glomerular filtration rate (GFR), estimated according to the Mayo clinic equation for healthy subjects, was inversely correlated with large-artery stiffness, as assessed by aortic PWV (r=-0.34; P<0.001), and with peripheral artery stiffness, as assessed by upper-limb PWV (r=-0.25; P<0.001). In a multivariate linear regression, aortic PWV was independently predicted by age (beta=0.48; P<0.001), mean arterial pressure (beta=0.14; P=0.013), and GFR (beta=-0.13, P=0.029). Upper-limb PWV was predicted by GFR (beta=-0.24; P<0.001) and mean arterial pressure (beta=0.20; P<0.001). We conclude that, in hypertensive patients with normal renal function, an inverse relationship exists between GFR and stiffness of both central elastic and peripheral muscular arteries. These relations are in part independent from the effect of several confounders, including age, sex, and blood pressure values.  相似文献   
994.
995.
BACKGROUND AND PURPOSE: Creation of an optimal retroperitoneal space is of pivotal importance in laparoscopic retroperitoneal surgery. The aim of this study was to examine the balloon dissecting technique developed at our institution, comparing the costs of our device with that of a commercially available balloon retroperitoneal expander. PATIENTS AND METHODS: Twenty patients scheduled to undergo retroperitoneoscopic surgery were randomly divided in two groups. In group 1, retroperitoneal dilation was performed with the commercially available balloon expander. In group 2, we employed our balloon dilator created with two middle finger of No. 8 powder-free surgical gloves tied to a nondisposable 11-mm trocar and filled with 600 mL of saline employing two 60-mL syringes simultaneously. Subjective evaluation of the created space was performed blindly in both groups. Economic evaluation included the costs of the disposable materials and of the time required for dilation. RESULTS: In all cases, the dilation was considered good. In group 1, the median time required to dilate the retroperitoneal space was 3.15 minutes, whereas in group 2, the median time required was 1.16 minutes, and the time required to dissect the retroperitoneal space was 4.41 minutes (total 5.57 minutes). Considering the costs of the disposable material, the overall costs of creating the retroperitoneal space was 141.95 euro in group 1 and 60.27 euro in group 2 (P < 0.005). CONCLUSION: The original dissecting balloon employed at our institution is easy and fast and offers a valid option for the proper dissection of the retroperitoneal space. Moreover, it was revealed to be cost-effective compared with the commercially available device.  相似文献   
996.
The usefulness of treating varicocele in order to improve fertility is still a matter of debate. The aim of this study was to evaluate variations in seminal parameters and inhibin B concentrations in a group of males affected by varicocele and treated by percutaneous retrograde sclerotherapy in comparison with a group of patients who did not undergo varicocele treatment. Thirty-eight patients with left varicocele underwent spermatic vein phlebography and percutaneous retrograde sclerotherapy with hydroxy-polyaethoxy-dodecanol. Serum inhibin B, follicle-stimulating hormone (FSH), testosterone levels and seminal parameters (sperm concentration, motility and morphology) were performed before and 6 months after sclerotherapy. Forty patients with left varicocele who did not undergo sclerotherapy were studied as controls. A significant increase (p < 0.01) in serum inhibin B levels and a significant decrease (p < 0.05) in FSH levels were observed 6 months after treatment. Semen analysis showed a significant improvement in sperm concentration (p < 0.05) and progressive motility (p < 0.01) after treatment. In control group no significant variations in hormonal and seminal parameters were observed 6 months after the basal examination. Six months after the basal evaluation, inhibin B levels were significantly higher in treated subjects than in controls (p < 0.05) whereas FSH levels were significantly lower (p < 0.05). Sperm concentration and progressive motility were significantly increased (p < 0.05 and p < 0.001, respectively) in treated subjects in comparison with controls. In conclusion, varicocele sclerotherapy improves inhibin B levels and seminal parameters, confirming the positive effect of this treatment on spermatogenesis and Sertoli cell function.  相似文献   
997.
BACKGROUND: The pedicled TRAM (pTRAM) flap is one of the best options for autologous breast reconstruction, but vascular complications reported in the standard versions are about 30%. To reduce complication rate, especially in high-risk patients, surgical delay has been suggested.Individual precise preoperative location and evaluation of perforating vessels and of variations of the diameter of the deep superior epigastric artery (DSEA) are highly desirable for improving surgical strategy. Previous reports using color duplex scanning, although generally confirming the validity of the delay maneuver, have showed several pitfalls. The aim of this report was to demonstrate the usefulness of multidetector computed tomography angiography (MDCTA) for preoperative planning in patients undergoing pTRAM flap breast reconstruction after selective vascular delay. METHODS: Three patients were considered for breast reconstruction with the pTRAM flap. An MDCTA was performed before and after selective delay to locate the muscle perforators and to show increase in DSEA diameter. Axial images, multiplanar reconstruction, and 3D volume images were analyzed. RESULTS: Accurate identification of the main perforators was achieved. Location, course, and anatomic variations of DSEA were reported. The average increase in diameter of the DSEA was 29.3%. CONCLUSION: Preoperative planning of pTRAM flap with MDCTA allows surgeons to visualize and locate the dominant perforators and to select the best DSEA. Consequently, the choice between the homolateral or contralateral rectus muscle is facilitated. The high sensitivity and specificity and the ease of interpreting data have made MDCTA a highly promising diagnostic tool for planning a pTRAM flap.  相似文献   
998.
OBJECTIVES: The aim of this retrospective study was to evaluate the results of our miniperc series through comparison with results from standard percutaneous nephrolithotomy (PNL) and tubeless PNL series in the treatment of stones <2 cm in diameter. PATIENTS AND METHODS: A total of 134 percutaneous treatments were performed for renal stones <2 cm in diameter. Among the treatments, 40 were minipercs, 67 were standard PNLs, and 27 were tubeless PNLs. RESULTS: Miniperc operative time was longer than that of standard PNL (155.5 vs 106.6 min, respectively) and tubeless PNL (95.9 min). Conversely, there was an advantage for miniperc over standard PNL in terms of a significantly reduced hematocrit drop (4.49% vs 6.31%). No miniperc patients required blood transfusions, whereas two did in the standard PNL group and one in the tubeless PNL group. There was no statistical difference in terms of the amount of analgesics between the standard PNL and miniperc groups, although this difference was statistically significant between the miniperc and tubeless PNL groups (73.8 vs 41.1mg, respectively). Hospitalization for the miniperc group was shorter than that required by the standard PNL group (3.05 vs 5.07 days), but tubeless PNL offered the best result (2.18 days). The stone-free rate was 100% in the tubeless PNL group, 94% in the standard PNL group, and 77.5% in the miniperc group. CONCLUSIONS: Our retrospective study failed to demonstrate significant advantages of the miniperc technique. As such, we no longer perform miniperc but instead use tubeless PNL when possible.  相似文献   
999.
Nicotine, the major psychoactive agent present in tobacco, acts as a potent addictive drug both in humans and laboratory animals, whose locomotor activity is also stimulated. A large body of evidence indicates that the locomotor activation and the reinforcing effects of nicotine may be related to its stimulatory effects on the mesolimbic dopaminergic function. Thus, it is now well established that nicotine can increase in vivo DA outflow in the nucleus accumbens and the corpus striatum. The stimulatory effect of nicotine on DA release most probably results from its ability to excite the neuronal firing rate and to increase the bursting activity of DA neurons in the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA), and from its stimulatory action on DA terminals in the corpus striatum and the nucleus accumbens. The neurochemical data are consistent with neuroanatomical findings showing the presence of nicotinic acetylcholine receptors (nAChRs) in the SNc, the VTA, and in projection areas of the central dopaminergic system such as the corpus striatum and the nucleus accumbens. Several lines of evidence indicate that the reinforcing properties of drugs of abuse, including nicotine, can be affected by a number of transmitter systems which may act by modulating central dopaminergic function. In this paper, the neurobiological mechanisms underlying nicotine addiction will be reviewed, and the possible strategies for new pharmacological treatments of nicotine dependence will be examined.  相似文献   
1000.
Metabolic syndrome (MS) and "low grade" systemic inflammation (LGSI) are very common findings in the older population. Although MS and LGSI have been associated in adults, it is not known what is the real contribution of MS, and its single components, to LGSI in older persons, due to the potential confounding effect of comorbidity and aging. We investigated the relationship between increased C-reactive protein (CRP) plasma levels, a marker of LGSI, and MS in 1044 older (> or =65 years) community dwelling Italian individuals enrolled the InChianti study. Metabolic syndrome was defined by the NCEP-ATP III-AHA/NHLBI criteria. High sensitivity CRP (hs.CRP) levels were measured by enzyme-linked immunosorbent assay, and defined as high when >3mg/L. The overall prevalence of MS was 31%. The prevalence of high hs.CRP was 54.5% in subjects with, and 41.3% in those without MS (p<0.001). MS was associated with high hs.CRP levels after adjustment for age, gender, and comorbidity (OR: 1.93, 95% CI: 1.46-2.55). Compared to subjects with MS and no LGSI, individuals with MS and LGSI were characterized by higher waist circumference, BMI, and HOMA score. Multivariate logistic regression analysis confirmed the association between waist circumference and high hs.CRP levels in subjects with MS (waist circumference III vs. I tertile OR: 2.60, 95% CI: 1.79-3.77) independent of age, gender, and important confounding variables including comorbidity. Additional analyses, conducted with and without dichotomization of hs.CRP levels, confirmed the central role of waist circumference in the LGSI phenomenon, independent of gender and diagnosis of MS. We conclude that in older individuals, MS is associated with LGSI, but the association is mainly supported by a strong independent correlation between waist circumference and high hs.CRP levels. In the absence of this specific MS component, it seems that the contribution of MS to LGSI would be modest at best.  相似文献   
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