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951.
952.
OBJECTIVES: The analytical performance of a new automated HPLC system, for the determination of HbA1C in blood (Tosoh HLC-723 G7), was studied. DESIGN AND METHODS: The study design included the evaluation of imprecision, linearity, interference and carryover. Comparison study was performed by comparing HbA1C results with those obtained from an established method (Bio-Rad Variant II). RESULTS: Total imprecision was less than 1.34% and the results were linear up to 17.2% HbA1C. The method showed a wide analytical range, and no carryover between specimens. Comparison study yielded, r=0.989, Sy.x=0.255, regression equation (y=0.9895x-0.35); Bland-Altman plot showed a mean bias=- 0.43% HbA1C with confidence limits ranging from -0.48% to -0.38% HbA1C. The presence of abnormal hemoglobin was clearly revealed, and no interference from labile HbA1C was apparent. CONCLUSION: The HLC-723 G7 instrument seems to be a reliable system for routine assay of HbA1C.  相似文献   
953.
Gianni C  Caretta G  Romano C 《Mycoses》2003,46(9-10):430-432
Geomyces pannorum var. pannorum is an ubiquitous saprophytic fungus frequently isolated from the soil and from air samples. It has rarely been reported as an animal or plant pathogen and it is an occasional aetiological agent of superficial infection of skin and nails in humans. Here, we report a case of superficial infection of the skin due to this fungus in a healthy man. The patient was treated orally with terbinafine 250 mg daily and topic bifonazole with complete resolution in 2 months.  相似文献   
954.
The association of doxorubicin (DOX) and paclitaxel (PTX) is very active in breast cancer. Unfortunately, PTX may potentiate the cardiotoxic effects of anthracyclines: it causes nonlinear disposition of DOX and its metabolites, leading to persistant of elevated plasma concentrations of the anthracyclines. However, this pharmacokinetic interference is not sufficient to explain the enhanced cardiotoxicity of the combination. Recent data suggest that PTX stimulates the conversion of DOX to cardiotoxic metabolites (namely doxorubicinol) inside cardiomyocytes. Docetaxel (DTX) does not have a major influence on DOX plasma concentration because it does not interfere with its elimination. Clinical data suggest that DTX may not enhance anthracycline cardiotoxicity, but patients seldom received a total anthracycline dose compatible with increased risk. Furthermore, there are experimental data indicating that DTX can also stimulate the metabolism of DOX to toxic species in human heart.  相似文献   
955.
956.
RA is a systemic autoimmune disorder primarily involving the joints. Extra-articular manifestations of RA often include lung involvement with heterogeneous clinical presentation and radiological findings. Autopsy studies reveal that the percentage of RA patients with pathological changes in the lung is significantly higher than that of patients with clinical manifestations. Lung alterations in RA may be primary or secondary to pharmacological treatments and may involve the alveoli, the interstitium, the airways and/or the pleura. These alterations may significantly impair lung function and some of them are potentially life-threatening. Thus, clinical examination and lung function testing should be performed in all patients with RA at the time of diagnosis and during follow-up. Those patients with clinical alterations and/or impaired lung function should undergo a complete radiological study.  相似文献   
957.
Glucosylceramide synthase (GCS), the key enzyme in the biosynthesis of glycosphingolipids, has been implicated in many biological phenomena, including multidrug resistance. GCS inhibition, by both antisense and the specific inhibitor (D-threo)-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), results in a drastic decrease of apoptosis induced by the p53-independent chemotherapeutic agent N-(4-hydroxyphenyl)retinamide in neuroepithelioma cells. By using the yeast two-hybrid system, we have identified a member of the reticulon (RTN) family (RTN-1C) as the major GCS-protein partner. Interestingly, RTN-1C not only interacts with GCS at Golgi/ER interface but also modulates its catalytic activity in situ. In fact, overexpression of RTN-1C sensitizes CHP-100 cells to fenretinide-induced apoptosis. These findings demonstrate a novel p53-independent pathway of apoptosis regulated by Golgi/endoplasmic reticulum protein interactions, which is relevant for cancer combined therapy.  相似文献   
958.
BACKGROUND: There is little evidence in the literature on the benefits of cold blood cardioplegia in pediatric cardiac surgery. This study investigates the effects of cold crystalloid versus cold blood cardioplegia on myocardial metabolism, reperfusion injury, and clinical outcomes in patients undergoing ventricular septal defect (VSD) repair. METHODS: Patients were randomly assigned to receive antegrade cold (4 to 6 degrees C) St Thomas's I crystalloid (CCC) or blood (CBC) cardioplegia. Changes in myocardial adenine nucleotides and purine levels were monitored in right ventricular biopsies and postoperative serum troponin I (TnI) and lactate release were measured. RESULTS: Forty patients were randomly assigned to CCC (n = 21; age 21.1 +/- 40.8 months) or to CBC (n = 19; age 27.4 +/- 39.3 months). Patient characteristics were similar in the two groups and there was no mortality. After the ischemic period there was a significant drop in adenosine triphosphate levels compared with control values in the CCC (40.4 +/- 9.9 versus 27.5 +/- 12.5 nmol/mg protein, p = 0.01) but not in the CBC group (40.3 +/- 23.2 versus 37.3 +/- 18.9 nmol/mg protein). The fall was more marked in infants compared with children (40% versus 10%, respectively, p = 0.01). Mean total TnI release was 42% lower in the CBC than the CBC group (95% confidence interval 10% to 62%, p = 0.015). Total TnI release was significantly associated with age (p < 0.001) but as levels in infants in the CBC group were the same as for children, the reduction with age was seen almost entirely in the CCC group. There were no differences in the duration of inotropic support, ventilation time, intensive care unit, or hospital stay in the two groups. CONCLUSION: The use of CBC is associated with less metabolic myocardial ischemic stress and reperfusion injury when compared with CCC in pediatric patients undergoing VSD repair.  相似文献   
959.
BACKGROUND: Right ventricular assist devices (RVADs) have been proposed to improve exposure of the coronary arteries in off-pump surgery. In this study we investigated the impact of the A-Med RVAD on inflammatory response and organ function in patients undergoing coronary artery bypass grafting. METHODS: Sixty patients were prospectively randomized to conventional surgery with cardiopulmonary bypass (CPB) and cardioplegic arrest, beating heart surgery (off-pump), or beating heart surgery with the RVAD. Serial blood samples were collected postoperatively, for analysis of inflammatory markers, troponin I, protein S100, and free hemoglobin. Renal tubular function was assessed by measuring urine N-acetyl-glucosaminidase activity. RESULTS: No hospital deaths or major postoperative complications occurred in the study population. Interleukin-6, interleukin-8, C3a, and troponin I levels after surgery were significantly higher in the CPB group compared with the off-pump and RVAD groups. Free hemoglobin levels immediately after the operation, peak and total S100 levels, and N-acetyl-glucosaminidase activity were also significantly higher in the CPB group. CONCLUSIONS: Off-pump coronary revascularization, with or without RVAD, reduces inflammatory response, myocardial, neurologic, and renal injury, and decreases hemolysis when compared with conventional surgery with CPB and cardioplegic arrest.  相似文献   
960.
BACKGROUND: This study analyses the development of off-pump coronary artery bypass (OPCAB) surgery training at a single institution, and compares the early and midterm clinical outcomes of OPCAB and conventional coronary artery bypass grafting (CABG) procedures performed by trainees with or without direct consultant cardiothoracic surgeon supervision. METHODS: Analysis was undertaken on data prospectively recorded on a computer database (Patient Analysis and Tracking System). Of the 2,422 CABG operations performed between January 1999 and December 2001, 969 (40%) were carried out by trainees either off pump (422) or on pump (547). RESULTS: Although the total number of CABG operations performed by trainees remained constant, there was a significant increase in the number of OPCAB operations during the study period compared with conventional CABG, as well as an increase in the average number of grafts per patient in the OPCAB group (both p < 0.05). Furthermore, a significant trend towards using two or more arterial conduits in the OPCAB group was observed in the study period. The number of OPCAB operations performed by trainees as independent operators without direct consultant supervision also increased significantly (p < 0.05). Early and midterm clinical outcomes were similar between patients operated by trainees on pump or off pump as independent operators versus under direct consultant supervision. CONCLUSIONS: The significant increase in OPCAB operations performed by trainees as independent operators or under direct consultant supervision, as well as the increase in the number of grafts per patient and arterial conduits used for myocardial revascularization, demonstrate a progression of training in beating heart surgery for cardiothoracic trainees. Improvements in the techniques have made it safe to teach trainees off-pump multivessel coronary artery revascularization.  相似文献   
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