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1.
Early changes in lipid metabolism and appearance of atherosclerosis risk factors play a key role in the development of cardiovascular disease of chronic renal failure (CRF). In the effort to evaluate the effects of protein restricted diet on dyslipidemia, we studied 122 patients with CRF (S-creatinine 1.3-9 mg/dl); 58.2% of whom were on antihypertensive drugs treatment. Patients had been separated into 6 groups: group 1 was kept on a free diet; groups 2, 3, 4, 5, 6 were kept on a protein-restricted diet from 12, 24, 36, 48, 60 months, respectively. We found hypertriglyceridemia, pathologic levels of esterified cholesterol in high density lipoprotein (HDL-C) and pathologic apolipoprotein A1/B ratio in group 1; the comparison with other groups--whose values were normal range after 12, 24 months of treatment--showed significant differences. The lipidic parameters were independent of the duration of CRF and of patients' age. Serum creatinine showed a significant correlation with tryglicerides and HDL-C values only in group 1. Total cholesterol and apolipoprotein B were significantly greater in hypertensives than in normotensives. In our opinion, a moderate restriction in protein intake could be effective in preventing and in halting the early alterations of lipid metabolism in CRF.  相似文献   
2.
BackgroundWe aim to evaluate the impact of multiparametric magnetic resonance imaging and fusion-target biopsy for early reclassification of patients with low-risk Prostate Cancer in a randomized trial.Materials and methodsBetween 2015 and 2018, patients diagnosed with Prostate Cancer after random biopsy fulfilling PRIAS criteria were enrolled and centrally randomized (1:1 ratio) to study group or control group. Patients randomized to study group underwent multiparametric magnetic resonance imaging at 3 months from enrollment: patients with positive findings (PIRADS-v2>2) underwent fusion-target biopsy; patients with negative multiparametric magnetic resonance imaging or confirmed ISUP - Grade Group 1 at fusion-target biopsy were managed according to PRIAS schedule and 12-core random biopsy was performed at 12 months. Patients in control group underwent PRIAS protocol, including a confirmatory 12-core random biopsy at 12 months. Primary endpoint was a reduction of reclassification rate at 12-month random biopsy in study group at least 20% less than controls. Reclassification was defined as biopsy ISUP Grade Group 1 in >2 biopsy cores or disease upgrading.ResultsA total of 124 patients were randomized to study group (n = 62) or control group (n = 62). Around 21 of 62 patients (34%) in study group had a positive multiparametric magnetic resonance imaging, and underwent fusion-target biopsy, with 11 (17.7%) reclassifications. Considering the intention-to-treat population, reclassification rate at 12-month random biopsy was 6.5% for study group and 29% for control group, respectively (P < 0.001).ConclusionsThe early employment of multiparametric magnetic resonance imaging for active surveillance patients enrolled after random biopsy consents to significantly reduce reclassifications at 12-month random biopsy.  相似文献   
3.
Until recently, MR examinations of the pancreas were limited by motion artifacts, vascular pulsatility and poor spatial resolution. Today, new techniques have been developed, which allow to overcome these problems and provide additional information such as selective images of biliary and pancreatic ducts and vascular structures. MR examinations of the pancreas need to include either breath-hold or nonbreath-hold morphological T1- and T2-weighted images; a contrast agent is required when the study is performed with fast imaging which allow the acquisition of dynamic images in arterial and portal venous phases. Recently, a new liver-specific contrast agent (Mn-DPDP) has been demonstrated to provide selective pancreatic enhancement. As a complement to baseline sequences, MR cholangiopancreatography images can be acquired, possibly integrated by functional examination after secretin administration. Finally, contrast-enhanced MR angiography opens new perspectives for vascular studies, particularly for the locoregional staging of pancreatic cancer.  相似文献   
4.
OBJECTIVE: To determine the role of MR imaging in the localization of pancreatic insulinomas in patients with clinical and laboratory diagnosis of insulin-producing tumor. MATERIAL AND METHODS: Thirty-one patients presenting with signs and symptoms of pancreatic insulinomas were prospectively included in our study. Twenty-six patients underwent surgery, and pathologic specimens were examined: 5 patients, in whom the initial diagnosis of insulinoma was excluded, were also studied and then followed up. All patients were studied with a high gradient power 0.5 T magnet. Images were evaluated by 2 radiologists blinded to previous investigations, tests and results. RESULTS: MR imaging correctly localized 24 of the 26 insulinomas (2 were false-negative and 1 false-positive) and was correctly negative in the 5 control patients. The interobserver agreement had a kappa value of 0.89. CONCLUSION: MR imaging was accurate in localizing pancreatic insulinomas and as a consequence, patients in our institution are now submitted to surgery directly after the MR examination. Invasive methods are considered only in cases in which, despite clear biochemical results, MR imaging has not demonstrated a pancreatic focal lesion.  相似文献   
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6.
Blood and plasma viscosity, as well as erythrocyte filtration rates were studied in 44 osteopenic (20 men and 24 women) and in 40 non-osteopenic (20 men and 20 women) patients, all over 65 years of age. Pathological hemorheological parameters were observed only in 12 subject of the osteopenic group, and 10 controls. The results indicate that although the hemorheological parameters do not show a direct correlation with the osteopenia, it is worthwhile following these parameters, among others, in order to optimize the treatment with anti-osteoporotic drugs which are able to regulate them.  相似文献   
7.
Pectoral flippers of cetaceans function to provide stability and maneuverability during locomotion. Directional asymmetry (DA) is a common feature among odontocete cetaceans, as well as sexual dimorphism (SD). For the first time DA, allometry, physical maturity, and SD of the flipper skeleton—by X‐ray technique—of Pontoporia blainvillei were analyzed. The number of carpals, metacarpals, phalanges, and morphometric characters from the humerus, radius, ulna, and digit two were studied in franciscana dolphins from Buenos Aires, Argentina. The number of visible epiphyses and their degree of fusion at the proximal and distal ends of the humerus, radius, and ulna were also analyzed. The flipper skeleton was symmetrical, showing a negative allometric trend, with similar growth patterns in both sexes with the exception of the width of the radius (P ≤ 0.01). SD was found on the number of phalanges of digit two (P ≤ 0.01), ulna and digit two lengths. Females showed a higher relative ulna length and shorter relative digit two length, and the opposite occurred in males (P ≤ 0.01). Epiphyseal fusion pattern proved to be a tool to determine dolphin's age; franciscana dolphins with a mature flipper were, at least, four years old. This study indicates that the flippers of franciscana dolphins are symmetrical; both sexes show a negative allometric trend; SD is observed in radius, ulna, and digit two; and flipper skeleton allows determine the age class of the dolphins. Anat Rec, 297:1181–1188, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
8.
Bexarotene is approved for the treatment of cutaneous T cell lymphomas in patients refractory to at least one prior systemic therapy. Associated hypertriglyceridaemia requires monitoring, but can readily be managed with concomitant medication, such as fenofibrate. Here we report three cases of hypertriglyceridaemia secondary to bexarotene assumption, which was adequately managed with omega-3 fatty acids. If fenofibate-related side effects occur, or a statin is required to control low-density lipoprotein-cholesterol, omega-3 fatty acids should be considered as a good alternative therapy to lower lipid levels during bexarotene treatment.  相似文献   
9.
OBJECTIVE: To compare the plasma pharmacokinetics of lamivudine 150mg twice daily and 300mg once daily in patients with HIV-1 infection. DESIGN: Nonblind, sequential, pharmacokinetic study. PARTICIPANTS: 13 patients with HIV-1 infection (median age 36 years). METHODS: Patients were tested during twice daily and then once daily regimens of lamivudine. In both regimens, the total daily dose of lamivudine was identical (300 mg/day). Blood samples for pharmacokinetic analysis were taken over a 12-hour period after > or =7 days of twice daily administration, and again over a 24-hour period after 7 days of once daily administration,. RESULTS: 12 patients completed the study. Lamivudine pharmacokinetic parameters (mean +/- SD) after administration of 150mg twice daily were: peak plasma concentration (Cmax) 2077+/-816 microg/L; trough plasma concentration (Cmin) 332+/-219 microg/L; elimination half-life (t 1/2beta) 6.1+/-1.9h; time to Cmax (t(max)) 1.6+/-0.7h; average concentration over the dosage interval (Cav) 711+/-269 microg/L; and area under the concentration-time curve (AUC) over 2 dosage intervals (24h) 17085+/-6464 microg x h/L. Corresponding values after administration of 300mg once daily were: Cmax 3461+/-854 microg/L; Cmin 146+/-87 microg/L; t1/2 7.9+/-3.4h; t(max) 2.2+/-1.3h; Cav 705+/-177 microg/L; and AUC over 1 dosage interval (24h) 16644+/-4150 microg x h/L. Statistical analysis showed a significant difference (p < 0.05) between the 2 schedules for Cmax and Cmin values, whereas no significant differences emerged for the other parameters. CONCLUSIONS: Once daily lamivudine leads to a similar exposure in plasma as twice daily administration of the same total daily dose. Since once daily administration may result in improved compliance, these results provide the pharmacokinetic basis for using lamivudine in a once daily regimen. Randomised clinical studies are needed to confirm this pharmacokinetic finding.  相似文献   
10.
MK-852, a cyclic heptapeptide, is a potent platelet fibrinogen receptor antagonist. When administered to normal healthy male subjects by 1- and 4-hour constant rate intravenous infusions, it provides a generally well-tolerated and reversible means of inhibition of platelet function. At infusion rates of 1 microgram/kg/min for 1 hour and 0.44 microgram/kg/min for 4 hours, respectively, MK-852 extended baseline bleeding time by greater than 2.2-fold and 2.6-fold, inhibited ADP-induced platelet aggregation by 76% and 69%, and inhibited collagen-induced platelet aggregation by 65% and 67%, respectively. The pharmacokinetics of MK-852 include an elimination half-life of approximately 2 hours, total clearance of about 150 ml/min, and volume of distribution of about 18 liters. Examination of the relationship between MK-852 whole-blood concentration in vitro and inhibition of platelet aggregation showed an EC50 of about 55 ng/ml and a Hill coefficient of 1.55. The infusions were generally well tolerated, with no study drug-related changes in blood counts or biochemical profiles.  相似文献   
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