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BACKGROUND: Increased troponin I (TnI) has been detected in congestive heart failure (CHF) patients. We demonstrate that occurrence of LVH, and systolic and diastolic blood pressure values (SBP and DBP, respectively) correlate with increasing levels of serum TnI in a selected CHF population. METHODS: Our team reviewed the medical records of 40 consecutive patients admitted with CHF symptoms, low clinical suspicion of myocardial infarction (MI), and serum TnI measured upon admission. Twenty numerical and categorical parameters were screened. Patients were divided in to seven non-exclusive groups by increasing cutoff values of serum TnI (0, 0.1, 0.2, 0.3, 0.4, 0.6, and 1.5 ng/ml). In each group the average value of numerical parameters and the occurrence of categorical ones were calculated. The correlation between these values and the seven TnI cutoffs were analyzed. RESULTS: Occurrence of electrocardiographic left ventricular hypertrophy (ECG-LVH), and average values of SBP and DBP significantly correlated with the TnI cutoffs by means of multiple regression analysis (P = 0.001, 0.02 and 0.007, respectively). CONCLUSION: ECG-LVH and values of SBP and DBP significantly correlate with increasing cutoff levels of serum TnI in hospitalized patients with CHF and low clinical suspicion of MI.  相似文献   
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Role of Ang1 and its interaction with VEGF-A in astrocytomas   总被引:2,自引:0,他引:2  
Angiopoietins (Ang1 and Ang2) modulate the activity of the endothelial cell (EC)-specific receptor tyrosine kinase Tie2, which together with vascular endothelial growth factor (VEGF-A) and its EC-specific receptors, VEGFR1 and VEGFR2, regulate normal physiological vessel development. The functional role of angiopoietins in tumor angiogenesis, in particular astrocytoma angiogenesis, remains unclear. In this study, we focus on the specific contribution of Ang1 to the vascular growth of glioblastoma multiforme (GBM) and its interactive role with VEGF-A. Subcutaneous and intracranial GBM xenografts were generated using 3 established astrocytoma cell lines (U87, U373, and U343) that were transfected to stably over-express Ang1. GBM xenografts were also generated to express low levels of VEGF-A and high Angl. We found that Ang1 increases the vascular growth of both subcutaneous and intracranial xenografts of GBM by approximately 3-fold. However, the increased vascular growth was only seen in xenografts with concurrent VEGF-A elevation, since decreasing VEGF-A expression resulted in a loss of the pro-angiogenic growth advantage seen with Ang1. Collectively, our data suggest that Ang1 regulates GBM vascularity in a VEGF-A dependent manner, synergizing the initial pro-angiogenic response that is triggered by VEGF-A and promoting the vascular growth of GBM.  相似文献   
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BACKGROUND: Doses of renally eliminated drugs should be adjusted according to kidney function to prevent adverse drug events and cost. Dose adjustment can be based on serum creatinine level, subsequent creatinine clearance estimation, and dosage calculation with consideration of the renal elimination properties of the respective compound. OBJECTIVE: Our objective was to quantify the impact and relevance of serum creatinine measurement error on dose adjustment in renal failure. METHODS: We analyzed 27914 measurements from external quality assessment surveys of 1878 German laboratories that used a kinetic alkaline picrate (69% of results) or an enzymatic method (25%) for creatinine determination. Linear models were fit for both methods combined and separately. On the basis of 95% confidence intervals (CIs) for creatinine values, 95% CIs for drug dosing were calculated. RESULTS: The 95% CI for a measured serum creatinine value was 0.80. Measured value < Reference method value < 1.28. Measured value for the kinetic alkaline picrate method and 0.87. Measured value < Reference method value < 1.21. Measured value for the enzymatic method. Applied to a data set of 6.5 million simulated patients with all possible combinations of characteristics relevant for drug dosing, the dosing error caused by serum creatinine measurement error did not exceed 25% in patients with creatinine clearance estimates lower than 50 mL/min according to the Cockcroft-Gault equation. For drugs completely eliminated by the kidneys in active form, the dosing error was up to 6-fold smaller than that which would occur if doses were not adjusted. CONCLUSION: The serum creatinine measurement error of current laboratory methods is small and is comparable to other errors influencing dose adjustment.  相似文献   
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Toljanic JA  Heshmati RH  Walton RL 《Annals of plastic surgery》2003,50(2):188-91; discussion 192
Postsurgical facial defects often pose a challenge to patient rehabilitation. Such defects can have a severe adverse effect on patient perceptions of body image and self-esteem. When immediate surgical repair of the defect is not feasible, an interim removable facial prosthesis may be considered. This prosthesis can be fabricated and placed as soon as several days after surgery to provide a cosmetically acceptable appearance, permitting the patient to more comfortably and confidently resume social interactions during the postoperative healing period. This article presents two case reports describing the use of interim facial prostheses to provide rapid patient rehabilitation.  相似文献   
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OBJECT: This study was conducted to investigate the familial and genetic contribution to intracranial, abdominal aortic, and all other types of aneurysms, and to define familial relationships among patients who present with the different aneurysm types. METHODS: The authors used a unique Utah resource to perform population-based analysis of the familial nature of aneurysms. The Utah Population Data Base is a genealogy of the Utah population dating back eight generations, which is combined with death certificate data for the state of Utah dating back to 1904. Taking into account the genetic relationships among all aneurysm cases derived from this resource, the authors used a previously published method to estimate the familiality of different aneurysm types. Using internal, birth-cohort-specific rates of disease calculated from the database, they estimated relative risks by comparing observed to expected rates of aneurysm incidence in defined sets of relatives of probands. CONCLUSIONS: Each of the three aneurysm types investigated showed significant evidence for a genetic component. Relatives of patients with intracranial aneurysms do not appear to be at increased risk for abdominal or other lesions, but relatives of patients with abdominal aortic aneurysms appear to be at increased risk for other types of these lesions.  相似文献   
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This study evaluates the efficacy and side effects of a low dose of epidural morphine combined with clonidine for postoperative pain relief after lumbar disc surgery. In 36 of 51 patients who accepted the procedure, an epidural catheter was inserted (L1-L2 level). General anesthesia was induced with propofol and sufentanil, and maintained with sevoflurane in O2/N2O. After emergence from anesthesia, epidural analgesia was initiated according to two randomly assigned protocols: 1 mg of morphine with 75 microg of clonidine (Group M) or 12.5 mg of bupivacaine with 75 microg of clonidine (Group B), in 10 mL saline. Piritramide was administered during the first postoperative 24 hours using a patient-controlled analgesia device (PCA). The following parameters were recorded: piritramide consumption during the first 24 hours; pain at rest during the first postoperative hours (D0), during the first night (D1), and during the first mobilization; [visual analogue scale (VAS)]; and the occurrence of drowsiness, motor blockade, respiratory depression, nausea, vomiting, itching, micturition problems, and bladder catheterization during D0 and D1. Epidural administration of morphine-clonidine significantly improved postoperative pain relief and reduced piritramide consumption as compared to epidural bupivacaine-clonidine. Side effects did not differ between groups except for a higher incidence of micturition problems in Group M during D1. The occurrence of bladder catheterization was not significantly higher in that group. We conclude that a low dose of epidural morphine combined with clonidine offers a better postoperative analgesia than does bupivacaine-clonidine. The excellent analgesic conditions were obtained at the expense of a higher incidence of difficulties in initiating micturition.  相似文献   
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