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11.
Cardiac surgeries especially involving crux of the heart as performed in tetralogy of Fallot (TOF) and pulmonary stenosis are mainly responsible for junctional ectopic tachycardia (JET). Diversified antiarrhythmic agents have been used in an impressive way to treat JET but showed suboptimal efficacy and varied associated adverse effects. But, ivabradine has proved as final crusader for its treatment. We report our initial experience of 4 cases in last 6 months with ivabradine in the management of postoperative JET. Encouraged by various reports and our increasing experience with ivabradine in heart failure population, we have moved to ivabradine as the first drug of choice for postoperative JET. Bradycardia was the only significant adverse effect in our series. The availability of atrial and ventricular pacing wires or at least transvenous temporary pacing should be ensured before starting ivabradine.  相似文献   
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Amyloid beta-peptide (Abeta), the major constituent in senile plaques in Alzheimer's disease (AD) brain, is thought by many researchers to be central to neurotoxicity in AD brain. Increasing evidence from many laboratories indicates that AD brain is under oxidative stress, with strong evidence of protein oxidation, lipid peroxidation, and peroxynitrite damage. A link between the central role of Abeta and oxidative stress in AD brain may be Abeta-associated free radical oxidative stress. If so, antioxidants such as vitamin E should modulate Abeta-induced oxidative damage and neurotoxicity in brain cells. This review summarizes studies of Abeta-associated free radical oxidative stress and its inhibition by vitamin E in cortical synaptosomal membranes and hippocampal neuronal cells in culture. Taken together with the recent report that vitamin E slows the progression of AD, this review strongly supports a central role of Abeta-associated free radical oxidative stress in neurotoxicity in AD brain.  相似文献   
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Primary liposarcoma of the orbit is a rare tumour. There are very few cases of orbital liposarcoma reported in the literature, mostly of the myxoid variety. In this paper, the authors report the clinical presentation, histopathological features, results of diagnostic studies and management of a case of orbital low grade myxoliposarcoma with local recurrence, together with a review of the literature.  相似文献   
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Summary This study examines the paracrine influence by human breast carcinoma cells (UISO-BCA-1) on nonmalignant breast tissuein vitro. The 17-OH-SDH-mediated reductive pathway (estroneestradiol) was significantly increased in nonmalignant breast tissue coincubated with human breast carcinoma cells, compared to control tissues incubated in the media alone. No influence on the enzyme activity was noticed in coincubated breast cancer cells. Preincubation of breast cancer cells with estradiol (10–8 M) significantly decreased the enzyme activity in coincubated nonmalignant breast tissue, which was restored to control levels by addition of R5020 (10–8 M), tamoxifen (10–6 M), or a combination of both. In nonmalignant tissues incubated in the presence of growth factor TGF, enzyme activity was reduced to between 46% and 76%. No other growth factors (IGF I, IGF II, PDGF) influenced enzyme activity. In nonmalignant tissues incubated with malignant tumor cytosol, enzyme activity was increased in 16% cases, inhibited in 21%, and not significantly changed in 63%.The data from the present study suggest that factors produced by breast carcinoma cells may influence interconversion of estradiol in nonmalignant tissue. In patients, factors produced by malignant tumor mass may have paracrine influence on surrounding nonmalignant breast tissue and, thereby, may influence the estrogen availability to tumor mass.  相似文献   
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Studies of preemptive analgesia in humans have shown conflicting results. The study design, patient population and the duration of assessment of postoperative pain are important in the evaluation of preemptive analgesia. We carried out a prospective, randomized, double-blind controlled study in 80 patients of physical status ASA 1-3 undergoing upper abdominal and thoracic surgery. Patients received two epidural injections, one 20 minutes before induction and the other at the end of surgery. Study solution was either morphine (50 micrograms/kg), with or without 0.1% bupivacaine in 10 ml of normal saline, or normal saline alone. The study groups (Pre M, Pre MB) were given either morphine or morphine-bupivacaine before induction and saline at the end of surgery. The control groups (Post M, Post MB) were given saline before induction and morphine or morphine-bupivacaine at the end of surgery. Postoperative pain was assessed with a Visual Analogue Scale (VAS) during coughing and deep breathing at six-hourly intervals for five days. Epidural morphine was given if the VAS exceeded 4. Pre MB compared to Post MB had a significantly increased interval between the analgesic top-ups (P < 0.01) and decreased total postoperative morphine requirements (P < 0.0001) and number of top-ups (P < 0.001). Pre M and Post M were comparable. Pre MB compared to Pre M had significantly decreased total postoperative morphine requirements (P < 0.0001) and number of top-ups (P < 0.0001). Epidural morphine plus bupivacaine is effective as a preemptive analgesic. Morphine plus bupivacaine has better efficacy than morphine given alone before the induction of anaesthesia.  相似文献   
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Over a period of 15 months, 11 patients with phaeochromocytoma underwent retroperitoneoscopic excision of their tumours. Five patients had bilateral tumours. All patients underwent thorough preoperative evaluation and preparation with alpha- and beta-blockade. In the majority of the patients a hypertensive response was seen during generation of pneumoretroperitoneum. However, the period of tumour dissection and excision was devoid of large haemodynamic fluctuations. The average time taken was 3.5 to 4 hours per gland. Blood loss in successful laparoscopic excision averaged 240 ml (range 120 to 700 ml). In these patients satisfactory postoperative analgesia could be provided with intramuscular pethidine or intramuscular diclofenac sodium. In three patients the procedure had to be converted to open laparotomy due to haemorrhage. All three patients had preoperative radiological evidence of inferior vena cava and aortic involvement. Patient selection plays an important role in a successful outcome.  相似文献   
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PURPOSE: The aim of this study was to assess the efficacy of portoenterostomy in biliary atresia and determine factors that predict outcomes. METHODS: The outcomes after portoenterostomy for biliary atresia from 1976 to 1996 were graded into 3 defined groups: G (good, jaundice free); I (intermediate, progressive liver disease with liver transplant if needed after 3 years of age); P (poor, liver transplant or death at less than 3 years of age). RESULTS: Twenty-seven of 49 children (55%) who underwent portoenterostomy responded. Of these, 13 (26%) were jaundice free (G). Of 14 children (28%) in I, 6 underwent liver transplant after 3 years of age. Of 22 children (44.8%) in P, 14 (28%) died before 3 years and 8 underwent liver transplant before 3 years. Thus, 42% of the children in this series are surviving with native liver. Age at operation in P was significantly different compared with G. Preoperative values of bilirubin and alanine transaminase were comparable in the 3 groups. Postoperative values of bilirubin and alanine transaminase were lower in G and I compared with P Complications were significantly lower in group G. CONCLUSIONS: Portoenterostomy alone in biliary atresia is beneficial in 40% of cases. Factors associated with the outcome include age at operation, postoperative cholangitis, and change in values of bilirubin and alanine transaminase. A classification based on decline of bilirubin and enzyme levels 3 months after portoenterostomy is proposed to predict the long-term outcome of an individual case of biliary atresia. It is particularly relevant in the intermediate group in which timing of referral may preclude or compromise liver transplant.  相似文献   
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Objectives: To determine the quality of life (QOL) after stapes surgery and whether audiological parameters for hearing correlate with specific QOL factors. Design: A retrospective cross‐sectional study. Setting: A tertiary referral centre. Participants: A series of 35 patients who underwent stapes surgery of which three were excluded because they were <18 years of age, chronically or mentally ill, or in a dependant relationship. Response rate was 93% (30/32). Nine were further excluded because they had revision or bilateral surgery, or missing data. Twenty‐one patients were included in this study. Main outcome measures: The Glasgow Benefit Inventory (GBI) was used to evaluate general QOL and the Hearing Disability and Handicap Scale (HDHS) was used as a disease‐specific measure. The Belfast Rule of Thumb and Glasgow Benefit Plot assessed hearing outcomes. Results: Operative success was 86% using the Belfast Rule of Thumb and 95% had closure of the air–bone gap to within 20 dB. 81.8% of patients reported a better overall QOL as surgery. Glasgow Benefit Inventory Social and GBI Physical scores correlated positively with the HDHS speech component (P < 0.05). The duration of hearing loss correlated inversely with the average HDHS score (P < 0.05). Conclusion: The majority of patients report a better QOL as undergoing stapes surgery. Speech impacts on people's physical and social QOL of patients. Quality of life tools, in addition to objective audiologic measurements can provide clinicians with patients’ subjective perspective that helps guide clinical decision‐making and counselling.  相似文献   
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