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11.
The purpose of this study is to describe a subset of atypical hepatic hemangiomas that enhance rapidly and diffusely and to determine whether heavily T2-weighted images could distinguish between atypically enhancing liver hemangiomas and hypervascular malignancies. A retrospective search of MR records identified seven patients with liver hemangiomas that demonstrated diffuse early enhancement and 23 patients with biopsy-proven malignant liver lesions that were hypervascular on dynamic gadolinium-enhanced MR images. Quantitative analysis of signal intensity measurements was performed on the T2-weighted images, heavily T2-weighted (TE < 140), and dynamic gadolinium-enhanced images. Blinded reader comparison of the T2-weighted images and gadolinium-enhanced images was performed. Hypervascular hemangiomas enhanced to a greater degree than hypervascular malignant liver lesions on the early phase gadolinium-enhanced images. Perilesional parenchymal enhancement was demonstrated in five cases of rapidly enhancing hemangiomas. Signal intensity and contrast-to-noise ratios on the heavily T2-weighted images of the hemangiomas were significantly greater than that of the hypervascular malignant lesions (P < .05). Hemangiomas were differentiated from the hypervascular malignant liver lesions with high accuracy (97–100%) by three blinded readers based on the T2-weighted images. A subset of hemangiomas have atypical rapid diffuse enhancement on dynamic gadolinium-enhanced images. These atypical hemangiomas can be distinguished from hypervascular malignant liver lesions on T2-weighted MR images.  相似文献   
12.
OBJECTIVE: The purpose is to define factors influencing long-term patency of the internal thoracic artery (ITA) to optimize the operative strategy. METHODS: 1482 left internal thoracic artery (LITA) and 636 right internal thoracic artery (RITA) symptom-directed angiograms were studied in 1434 patients. Data were prospectively collected from patients who had primary coronary artery bypass surgery during the period 1982-2002. The mean age of patients was 59 years; 85% were male. The mean period from operation to re-angiogram was 80 months. LITA was grafted to left anterior descending coronary artery (LAD) in 82% of cases, RITA to right coronary artery (RCA) in 40% and circumflex artery in 35% of cases. Graft failure was defined as > or =80% stenosis. RESULTS: 96.3% of LITA and 88.1% of RITA grafts were patent. No patient variables were significantly associated with graft patency (age, gender, diabetes, hypertension, LVEF, NYHA, AMI). Target coronary artery was associated with patency of both LITA and RITA grafts with maximum patency when grafted to LAD (P = 0.02) RITA had the worst patency to RCA, patency for the left system was identical to LITA. Proximal anastomosis to aorta (free RITA) had significantly better patency when compared with in situ RITA to RCA system (P = 0.005) while similar patency when grafted to left system. ITA diameter and target artery diameter were not associated with graft patency. Recent operations had better RITA patency (P = 0.03). The interval from operation to angiogram was not associated with ITA patency (96% patency for LITA and 88% patency for RITA, remained stable when studied at <1, 1-4, 5-9, 10-14 and >15 years). CONCLUSIONS: Even in a patient cohort that had adverse symptoms, excellent LITA and RITA patency was achieved which almost remained constant through all time intervals studied.  相似文献   
13.
Detection of fetal hydronephrosis in utero, subsequent investigation, and surgical treatment is described. With the increasing use of ultrasound for obstetrical problems and greater experience with fetal sonography, more urologic abnormalities will be diagnosed prenatally.  相似文献   
14.
Background: Methicillin‐resistant Staphylococcus aureus (MRSA) infections continue to increase in UK hospitals despite the introduction of various control measures. These infections have serious clinical and economic implications, particularly in relation to elective orthopaedic surgery. Methods: A prospective study was performed from August 2003 to July 2004 to assess the effect of preadmission screening and ‘ring fencing’ of beds on the incidence of infection in an elective orthopaedics unit. Results: The preoperative incidence of MRSA colonization was 2.25% and 53% of these patients had at least one risk factor. There were no postoperative MRSA infections in the ring‐fenced orthopaedic unit. Conclusions: Preoperative screening and ring fencing reduced the MRSA incidence to zero in the operated patients. Mechanisms need to be developed where screening and isolation of MRSA cases can be performed in most, if not all, hospital admissions.  相似文献   
15.
We report outcome of 9-year follow-up of 50 Charnley cemented primary arthroplasties in 47 patients performed between 1996 and 1999. The minimum follow-up period was 5 years with a mean of 7 years. All hip joints were thoroughly assessed preoperatively to document patients’ functional level and Harris hip score was calculated. All the patients were disabled because of pain in hip and 45 (90%) had used walking aids. At follow-up all patients were living. The radiographs of all patients were available for the entire follow-up period. Of the 50 operated hips, only 2 patients (4%) complained of pain while all the rest were free of pain. Postoperatively only 10 (20%) patients used support for walking. At follow-up none of the hips were revised. Two patients (4%) had dislocation in postoperative period in which reduction was done under anesthesia. In one patient (2%) prosthesis and cement was removed because of deep infection. In two patients (4%) radiolucent clear zone was seen at bone cement interface on acetabular side and three (6%) patients had it on femoral component. None of the patients developed deep vein thrombosis or heterotopic bone. In postoperative period the Harris hip score was calculated in each case and compared with the preoperative score to evaluate the outcome. Significant improvement was found in Harris hip score after surgery.  相似文献   
16.
Two children out of three siblings of a family presented with tiredness, fatigue, and breathlessness for more than 6 months. Examination of peripheral blood smear, bone marrow aspirate, and a positive acidified serum test (HEMPAS) revealed these children to be a case of congenital dyserythropoietic anemia type II. This case is reported because of its rarity.  相似文献   
17.
OBJECTIVE: The purpose of this study was to examine the effect of peri-operative red blood cell (RBC) transfusion on 30-day and 1-year mortality following coronary artery bypass grafting (CABG). METHODS: We retrospectively analysed 3024 consecutive patients who underwent isolated CABG between January 1999 and December 2001. Patient records were linked to the National Strategic Tracing Service, which records all mortality in the UK. Thirty-day and 1-year mortality were derived from Kaplan-Meier curves. Confounding variables were controlled for by constructing a propensity score for the probability of receiving a transfusion from core patient characteristics including the lowest recorded laboratory haemoglobin (LL Hb) from a clinical chemistry database (C statistic 0.81). The propensity score and the comparison variable (transfusion versus no transfusion) were included in a Cox proportional hazards analysis, allowing calculation of adjusted hazard ratios (HR) and Kaplan-Meier survival curves. RESULTS: Nine hundred and forty (31.1%) patients received RBC transfusion during or within 72h of surgery. Predictors of the need for transfusion were LL Hb and lower body mass index, use of cardiopulmonary bypass, female sex, number of grafts, renal dysfunction, increased age, extent of disease, and prior CABG; these factors were all included in the propensity score. After 1-year of follow-up, 122 (4.03%) deaths occurred. The crude HR for 1-year mortality in patients transfused was 3.0 (P<0.001). After adjusting for the propensity score, re-operation for bleeding, peri-operative blood loss and post-operative complications, the adjusted 30-day mortality was 1.9% in transfused patients compared to 1.1% in patients not transfused (P<0.05). The adjusted HR for 1-year mortality in patients transfused was 1.88 (P<0.01). CONCLUSIONS: Peri-operative RBC transfusion after CABG is associated with an increased risk of mortality during a 1-year follow-up period, with a large proportion of deaths occurring within 30-days.  相似文献   
18.
Background: Animal and volunteer studies indicate that ropivacaine is associated with less neurologic and cardiac toxicity than bupivacaine. Ropivacaine may offer advantages when used for thoracic paravertebral block. This study was designed to describe the pharmacokinetics of ropivacaine after thoracic paravertebral block.

Methods: Twenty female patients undergoing elective unilateral breast surgery were randomly assigned to receive a single bolus thoracic paravertebral injection of 2 mg/kg ropivacaine, with or without 5 [mu]g/ml epinephrine. Simultaneous arterial and venous blood samples were obtained for plasma ropivacaine assay. Data were analyzed with NONMEM, using two possible absorption models: conventional first-order absorption and absorption following the inverse gaussian density function.

Results: Epinephrine reduced the peak plasma concentrations and delayed the time of peak concentration of ropivacaine in both the arterial and venous blood. The time course of drug input into the systemic circulation was best described by two inverse gaussian density functions. The median bioavailability of the rapid component was approximately 20% higher when epinephrine was not used. The mean absorption times were 7.8 min for the rapid absorption phase and 697 min for the slow absorption phase, with wide dispersion of the absorption function for the acute phase. The half-time of arterial-venous equilibration was 1.5 min.  相似文献   

19.
Family resources in terms of their qualitative (process) and quantitative (structure) nature influences the development of social competence in children/adolescents. Present study aims at exploring the relationship of family resource variables with three measures of social competence of 300 adolescent belonging to different socio-cultural status. Socio-culturally advantaged group samples were found to have healthy family environment, whereas, socio-culturally disadvantaged group perceived themselves as at disadvantages and were deprived in seeking positive intra-family support. However inspite of their disadvantages, they were found to be more self-competent. On the other hand, advantaged group adolescents were found to be more competent in the areas of peer and teacher related social competence. Product-moment coefficient correlation analysis revealed that parental education, occupation and family income were found to be significantly associated with positive peer and teacher related social competence in case of the samples belonging to the advantaged socio-cultural group. However, negative responses and outside family support was found to be positively associated with the development of disadvantaged group adolescent's self-related competence. In general, present study supports the hypothesis that Indian family system still continues to be considered as the major source of support for the adolescents, in spite of their growing tendency for independence, self-definition and autonomy.  相似文献   
20.
Adsorption and movement of carbofuran (a systemic nematicide) were studied using two Indian soils (clay loam and silt loam) of alluvial origin. Equilibrium adsorption coefficient (K) values measured using a batch-slurry technique follows the order clay loam greater than silt loam soil. The distribution coefficients (Kd) for both the soils in batch adsorption as well as in columns were also calculated. Carbofuran movement in soil columns during water infiltration in both air-dried and water-saturated columns was estimated. The order was as anticipated from K and Kd values. A larger amount of water was needed for leaching the carbofuran to 152 cm in clay loam soil than in silt loam soil. Carbofuran appears to increase in drier soils and in finer textured soils.  相似文献   
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