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991.
PURPOSE: It has been claimed that oral creatine supplementation might have potential cytotoxic effects on healthy consumers by increasing the production of methylamine and formaldehyde. Despite this allegation, there has been no scientific evidence obtained in humans to sustain or disprove such a detrimental effect of this widely used ergogenic substance. METHODS: Twenty young healthy men ingested 21 g of creatine monohydrate daily for 14 consecutive days. Venous blood samples and 24-h urine were collected before and after the 14th day of supplementation. Creatine and creatinine were analyzed in plasma and urine, and methylamine, formaldehyde, and formate were determined in 24-h urine samples. RESULTS: Oral creatine supplementation increased plasma creatine content 7.2-fold (P < 0.001) and urine output 141-fold (P < 0.001) with no effect on creatinine levels. Twenty-four-hour urine excretion of methylamine and formaldehyde increased, respectively, 9.2-fold (P = 0.001) and 4.5-fold (P = 0.002) after creatine feeding, with no increase in urinary albumin output (9.78 +/- 1.93 mg x 24 h(-1) before, 6.97 +/- 1.15 mg x 24 h(-1) creatine feeding). CONCLUSION: This investigation shows that short-term, high-dose oral creatine supplementation enhances the excretion of potential cytotoxic compounds, but does not have any detrimental effects on kidney permeability. This provides indirect evidence of the absence of microangiopathy in renal glomeruli.  相似文献   
992.
PURPOSE: To prospectively assess the use of cardiac MRI with delayed contrast enhancement (DCE) for identifying patients with active myocarditis among those presenting with acute coronary syndrome (ACS) but no coronary stenosis. MATERIALS AND METHODS: A total of 27 consecutive patients (age = 45 +/- 17 years; 14 male) presenting with ACS (chest pain, positive troponin-I) and no coronary stenosis, underwent cardiac MRI 9 +/- 7 days after pain onset and 8 +/- 5 months later (N = 19). Steady-state free-precession pulse (SSFP) sequence was applied for the assessment of myocardial function and both inversion-recovery (IR) and SSFP sequences were used for analyzing the topography and extent of DCE areas. Rest sestamibi-gated-single photon emission CT (SPECT) was also systematically performed. RESULTS: Subepicardial DCE pattern typical of acute myocarditis was documented in 12 patients (44%). Ischemic DCE pattern (transmural or subendocardial focal DCE) was documented in 12 of the 15 remaining patients (44%). Patients with subepicardial DCE had: higher C-reactive protein (CRP) levels (38 +/- 32 vs. 14 +/- 24 mg/mL; P = 0.04), lower Framingham cardiovascular risk (3 +/- 3% vs. 9 +/- 5%; P < 0.001), lower incidence of perfusion SPECT defects (17% vs. 73%; P = 0.01), higher left ventricular (LV) end-diastolic volume (77 +/- 16 vs. 64 +/- 10 mL/m(2); P = 0.02), and higher regression of DCE areas at follow-up (-65 +/- 17% vs. -18 +/- 23%; P = 0.002). CONCLUSION: DCE pattern of active myocarditis can be seen in patients presenting with ACS but no coronary stenosis.  相似文献   
993.
OBJECTIVES: To evaluate magnetic resonance imaging (MRI) at 3 T in the diagnosis and characterization of lesions of the finger flexor A2 pulley in patients with clinically suspected A2 pulley lesions. MATERIALS AND METHODS: Eight consecutive patients with clinically suspected lesions of the A2 pulley were included in this retrospective study. 3 T MRI was performed with T1-weighted, T2-weighted fat suppressed, and T1-weighted fat suppressed contrast enhanced sequences. The A2 pulley of all the fingers visible on the images were analyzed and pulley lesions characterized. RESULTS: All asymptomatic pulleys were normal at MRI. In the 8 symptomatic fingers 7 pulleys were abnormal at MRI. With the clinical examination as gold standard, sensitivity, specificity, positive predictive value, and negative predictive value of MRI were 87.5%, 100%, 100%, and 95.2% respectively. Characterization of the different pulley lesion was possible. CONCLUSION: MRI at 3 T allows reliable direct visualization and characterization of traumatic A2 pulley lesions.  相似文献   
994.
Sir, We read with great interest the recent article by Van Biesenet al. [1] on the standardization of creatinine and the implicationsfor chronic kidney disease (CKD) management. We fully agreewith the general conclusions. However, we would  相似文献   
995.

Purpose:

To assess the feasibility of magnetic resonance imaging (MRI) enhanced with ultrasmall superparamagnetic particles of iron oxide (USPIO) for assessing excitotoxic brain lesions in an experimental model of neonatal periventricular white matter (PWM) lesions.

Materials and methods:

Brain lesions were induced by intracerebral injection of ibotenate in 14 newborn rats. Pre- and post-USPIO T2-weighted MRI was performed in seven of them (group A) and in five control newborns (group C). In seven newborns with induced cerebral lesions, USPIO-enhanced MRI was not performed (group B). We compared the signal intensity of the lesion to the contralateral unaffected brain (lesion-to-brain contrast, LBC) and the lesion signal-to-noise ratio (SNR) before and after USPIO injection. MR imaging was correlated with histology.

Results:

USPIO injection significantly (P?<?0.05) decreased LBC and SNR of brain lesion but induced no changes in normal controls. The densities of macrophages and iron-laden cells were higher on the lesion side than on the contralateral side (P?<?0.05). Neither lesion size nor the surrounding macrophage infiltrate was significantly different between groups A and B.

Conclusion:

Post-USPIO T2-weighted MRI demonstrated negative enhancement of neonatal excitotoxic brain lesion. USPIO injection does not appear to exacerbate brain lesions.  相似文献   
996.
997.
We present the results at 8 years of the Spiesser study, a randomized trial comparing de novo sirolimus and cyclosporine in kidney transplant recipients at low immunologic risk. We assessed estimated glomerular filtration (eGFR), graft, patient, and death‐censored graft survival (log‐rank compared), de novo DSA appearance, risk of malignancy, post‐transplant diabetes mellitus (PTDM), and anemia. Intent‐to‐treat and on‐treatment analyses were performed. Graft survival was similar in both groups (sirolimus: 73.3%, cyclosporine: 77.7, P = 0.574). No difference was observed between treatment groups concerning patient survival (P = 0.508) and death‐censored graft survival (P = 0.858). In conditional intent‐to‐treat analysis, mean eGFR was greater in sirolimus than in cyclosporine group (62.5 ± 27.3 ml/min vs. 47.8 ± 17.1 ml/min, P = 0.004), in particular because graft function was excellent in patients maintained under sirolimus (eGFR = 74.0 ml/min). Importantly, no detrimental impact was observed in patients in whom sirolimus has been withdrawn (eGFR = 49.5 ml/min). Overall, 17 patients showed de novo DSAs, with no difference between the two groups (P = 0.520). Malignancy did not differ by treatment. An initial maintenance regimen based on sirolimus provides a long‐term improvement in renal function for kidney transplant patients, especially for those maintained on sirolimus.  相似文献   
998.
The efficacy and safety of tacrolimus twice‐a‐day (BID) and once‐a‐day (QD) formulations are similar. However, the available information regarding the initiation and management of tacrolimus QD is sparse and practical information is lacking. A panel of French experts extensively reviewed the available literature on tacrolimus pharmacokinetics, clinical efficacy, and safety in kidney transplantation and, based on their own day‐to‐day experience, provided the practitioners with practical guidelines for the daily use and management of tacrolimus QD in de novo initiation or early conversion.  相似文献   
999.
Altered expression of the genes that control apoptosis and proliferation may influence the response of cancer cells to cytotoxic agents. The primary aim of this study was to determine the role of the novel antiapoptotic and cell cycle gene, survivin, in apoptotsis and proliferation in esophageal cancer and to evaluate whether the survivin, p53, and bcl-2 status were able to predict a patient's response to neoadjuvant therapy. A total of 104 patients with esophageal tumors were studied. Tumor tissue was immunostained for survivin, p53, and bcl-2 proteins. Proliferative and apoptotic activity was measured using ki-67 immunohistochemical analysis and the TUNEL method, respectively. Forty-eight patients whose pretreatment biopsies were analyzed received neoadjuvant chemoradiation therapy or chemotherapy followed by surgery. Outcome was graded as a complete response, a partial response, or no response according to the results of histologic examination and CT imaging. Expression of survivin was found to correlate significantly with the proliferative index but not the apoptotic index. Patients who received neoadjuvant treatment were more likely to achieve a complete response if their tumors had high proliferative activity, and p53 positive tumors were more likely to contain residual tumor after treatment. In conclusion, survivin expression appears to foster proliferative activity in esophageal cancer, and tumors with a high proliferative index or a functioning p53 gene are more responsive to neoadjuvant chemoradiation therapy.  相似文献   
1000.
Laparoscopic versus open left lateral hepatic lobectomy: a case-control study   总被引:26,自引:0,他引:26  
BACKGROUND: After technical advances in hepatic surgery and laparoscopic surgery, some teams evaluated the possibilities of laparoscopic liver resections. The aim of our study was to assess the results of laparoscopic left lateral lobectomy (bisegmentectomy 2-3) and to perform a case-control comparison with the same operation performed by open surgery. STUDY DESIGN: From 1996 to 2002, 60 laparoscopic resections were performed in selected patients, including 18 left lateral lobectomies. The resected lesions were benign tumors, hepatocellular carcinomas with compensated cirrhosis, and metastases. Surgical procedures were performed with a harmonic scalpel, an ultrasonic dissector, linear staplers, and portal pedicule clamping when necessary. Results were compared with those of patients who underwent open left lateral lobectomies selected from our liver resection database in a case-control analysis. Both groups were similar for age, type and size of the tumor, and presence of underlying liver disease. RESULTS: Compared with laparotomy, laparoscopic left lateral lobectomies were associated with a longer surgical time (202 versus 145 minutes, p < 0.01), a longer portal triad clamping (39 versus 23 minutes, p < 0.05), and a decreased blood loss (236 versus 429 mL, p < 0.05). There were no deaths in either group, and the morbidity rates were 11% in the laparoscopic group and 15% in the open group. There were no specific complications of hepatic resection after laparoscopy (no hemorrhage, subphrenic collection, or biliary leak), but some were observed in the open group. CONCLUSIONS: This study demonstrates the safety of laparoscopic left lateral lobectomy. Despite longer operation and clamping time, without any clinical consequences, the laparoscopic approach was associated with decreased blood loss and absence of specific complications of the hepatic resection.  相似文献   
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