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991.
Metals and radionuclides in water systems can be easily adsorbed on suspended matter and, finally, they could eventually accumulate in the aquatic environment. The assessment of the health of a water body needs also sampling of the suspended matter fraction. In this paper sampling systems to characterise contaminants associated with the suspended matter fraction are described, with a particular attention to the collection and preservation of samples. Sampling must be representative, to obtain reliable conclusions. In this context it is stressed the importance of the evaluation of the sampling uncertainty, which contributes to a large extent to the total uncertainty.  相似文献   
992.
BACKGROUND: Outcomes of split-liver transplantation (SLT) with pediatric donors have never been specifically reported. METHODS: A prospective multicenter study on SLT using donors younger than 15 years was conducted. Thirty-nine split-liver procedures generating a left lateral segment (LLS) and an extended right graft (ERG) were performed. In three cases, no recipient was found for ERG. In all but one case, the celiac trunk was maintained with LLS. Data were available for 67 grafts (90% of the total): 38 LLSs and 9 ERGs transplanted into 46 children and 20 ERGs transplanted into 20 adults. Sixty-two (93%) grafts were used for primary transplants and five (7%) for retransplantation. SLT were performed with 15 donors 10 years of age and less and with 24 between 11 and 15 years. RESULTS: Median follow-up was 24 months. Two-year patient and graft survival were 87% and 82%. Patient and graft survivals were not significantly different between pediatric and adult recipients, between recipients from donors 10 years of age and less and those between 11 and 15 years, and between recipients of LLS and ERG. Arterial complications occurred in 6% of cases (8% in the < or = 10 year donors group, 5% in the 11-15 year donors group). The incidence of other complications was similar between groups. CONCLUSIONS: SLT with pediatric donors, even younger than 10 years, provided results comparable with those achievable using adult donors. The similar incidence of arterial complications among patients receiving LLS or ERG suggests that maintenance of the celiac trunk with LLS is not detrimental for right-sided grafts.  相似文献   
993.
BACKGROUND: The use of 24-hour ambulatory blood pressure monitoring is increasing in end-stage renal disease (ESRD) patients but the prediction power for cardiovascular complications of time-averaged ambulatory blood pressure components has been little investigated in these patients. METHODS: We analyzed the prognostic power of 24-hour ambulatory blood pressure monitoring for all-cause and cardiovascular mortality in 168 nondiabetic, events-free hemodialysis patients selected from a total dialysis population of about 450 patients. RESULTS: During the follow-up period (38 +/- 22 months), 48 patients died, 29 of them of cardiovascular causes. On univariate Cox regression analyses, the night/day systolic ratio resulted to be the sole blood pressure indicator to be associated with all-cause and cardiovascular mortality while left ventricular hypertrophy (LVH) was a strong predictor of these outcomes. In multivariable Cox models not including LVH, the night/day systolic ratio maintained an independent prognostic value for incident outcomes. However, when both risk factors, LVH and night/day systolic ratio, were introduced into Cox models, LVH was no longer a significant predictor while the night/day systolic ratio became a predictor of marginal statistical significance. CONCLUSION: The night/day ratio emerges as the sole ambulatory blood pressure monitoring-derived indicator providing significant prognostic information in patients with ESRD. However, this indicator as well as LVH loses substantial prediction power in statistical models including both risk factors. The results suggest that the night/day systolic ratio and LVH provide overlapping prognostic information, a phenomenon in keeping with the hypothesis that they represent a common pathway leading to adverse outcomes in ESRD.  相似文献   
994.
In the past 12 years, 16 thumb defects at, or distal to, the interphalangeal joint were reconstructed using a great toe mini wrap-around flap. A flap including the entire nail and most of the distal phalanx of the great toe was used. Fifteen of the grafts survived. The sensory recovery of the reconstructed thumb was good as assessed by 2-point discrimination test with an average of 10 mm (range 5-15), and there were no complaints of cold intolerance. This technique results in good cosmetic appearance, and all patients were pleased with the cosmetic aspect of the thumb and there was no significant morbidity at the great toe donor site. The final decision to reconstruct a distal thumb amputation is influenced by gender, job, and age of the patients. The great toe mini wrap-around flap is an excellent reconstruction technique in selected patients.  相似文献   
995.
BACKGROUND: Terlipressin has been suggested as the ideal drug to treat anesthesia-induced hypotension in patients under long-term renin-angiotensin system inhibitor treatment for arterial hypertension. The authors compared the effects of terlipressin and norepinephrine on systemic hemodynamic parameters and gastric mucosal perfusion using a laser Doppler flowmetry technique in patients treated with renin-angiotensin system inhibitors who experienced hypotension at induction of anesthesia. METHODS: Thirty-two patients scheduled for carotid endarterectomy under general anesthesia and treated with renin-angiotensin system inhibitors had hypotension after induction of general anesthesia. They were randomized to receive 1 mg of terlipressin (n = 16) or norepinephrine infusion (n = 16) to counteract anesthesia-induced hypotension. A laser Doppler probe was introduced into the gastric lumen. All measurements were performed just before surgery, during hypotension, at 30 min, and at 4 h. RESULTS: Terlipressin produced an increase in mean arterial pressure and a decrease in gastric mucosal perfusion detected by laser Doppler flowmetry (P < 0.05) over 30 min that were sustained for 4 h. During the infusion, norepinephrine produced an increase in mean arterial pressure and in gastric mucosal perfusion detected by laser Doppler flowmetry (P < 0.05). If compared to norepinephrine, terlipressin reduced oxygen delivery and oxygen consumption (P < 0.05) and increased arterial lactate concentrations (P < 0.05). CONCLUSION: This study showed the efficacy of terlipressin in the treatment of hypotension episodes in anesthetized patients chronically treated with renin-angiotensin system inhibitors, angiotensin converting-enzyme inhibitors, and angiotensin II receptor antagonists. However, the negative effects on gastric mucosal perfusion and the risk of iatrogenic oxygen supply dependency of terlipressin need to be taken into account.  相似文献   
996.
Persistent or recurrent disease is rare in low risk patients with papillary thyroid cancer, and follow-up of these patients is a matter of debate. Neck ultrasonography (US), serum thyroglobulin (Tg), and whole body scan (WBS) after T(4) withdrawal were performed in 456 patients, followed up to 5 yr. At the end of the first year, 335 patients were Tg negative, and 121 were Tg positive; 65 of 96 patients with Tg levels between 1 and 10 ng/ml became spontaneously Tg negative after 2 yr. During follow-up, WBS discovered node metastases in 13 subjects, and US discovered node metastases in 38 subjects (31 Tg positive and 7 Tg negative). WBS did not add any information, because all WBS-positive patients were also US and Tg positive. Fifty percent of metastases were less than 1 cm and not palpable. Finally, the negative predictive value of both negative Tg and US at first follow-up was 98.8%. We suggest a first follow-up based upon US assessment and stimulated (after T(4) withdrawal or recombinant human TSH) serum Tg determination; subsequently, 1) US should not be mandatory at each examination in initially Tg- and US-negative subjects, but is strongly suggested in all other cases; 2) Tg determination should be repeated 1 yr later, after exogenous or endogenous TSH stimulation only in initially Tg-positive patients without any other evidence of residual disease; and 3) Tg measurement during therapy should be sufficient in all other cases.  相似文献   
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OBJECTIVE: To determinate the profile of androstenedione (A), total (T), and free testosterone (FT), dehydroepiandrosterone (DHEA), DHEA-sulphate (DHEAS), sex hormone-binding globulin (SHBG), insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3) in non-smoking, postmenopausal women of normal weight and to search for correlations between hormones and carrier proteins and chronological age, number of years of postmenopause and age of onset of menopause. DESIGN: A group of 149 postmenopausal women aged 49 to 74 years were divided into three groups based on the number of years of postmenopause: 2-4 years (group A), 9-12 years (group B), and 19 years or more (group C). Seventy-two women aged 21 to 35 years were the controls. Hormones and carriers were assessed in all groups. RESULTS: A, DHEA, DHEAS, and IGF-I were significantly lower than controls in all groups, whereas T, FT, SHBG, and IGBFP-3 were lower only in groups B and C. All hormones and carriers were negatively correlated with the number of years of postmenopause; DHEA and T also showed a positive correlation with the age of onset of menopause. CONCLUSIONS: Androgens, SHBG, and IGF-I/IGFBP-3 show a diversified decline in postmenopause that is involved in the physiological aging process. Thus, a modification, in excess or deficiency, could favor the development of central symptoms or pathologies.  相似文献   
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