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91.
The reliability of helical CT as sole preoperative diagnostic technique for abdominal aortic aneurysms (AAA) and its accuracy in detecting vascular anomalies in the abdominal region was evaluated retrospectively in 42 patients with asymptomatic AAA > 40 mm. A single breath-holding helical scan was performed with 5 mm slice thickness, during a single injection of contrast medium, resulting in a 20 cm z-axis coverage. Axial images were reconstructed and used to generate high quality multiplanar reformatted images. Digital subtraction angiography (DSA) was performed in the first 18 patients and then in case of associated peripheral vascular disease (6 patients). Helical CT exactly showed, in all cases, the proximal and distal extent of the AAA. The visceral vessels as well as the inferior vena cava and renal veins were always clearly depicted, showing anatomical variants or pathological involvement in 19 patients. DSA gave sufficient details on the distal run-off but did not allow a reliable visualization of the visceral branches, venous anomalies and true extent of AAA. In our experience helical CT should be considered as the sole method for preoperative imaging of AAA. It allows a complete and precise evaluation; it is fast, with low doses of radiations and does not require hospitalization.  相似文献   
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BACKGROUND: The dysregulation of both myc gene expression and retinoid signaling pathways commonly occurs in small cell lung carcinoma (SCLC). Because preclinical data showed that all-trans-retinoic acid (RA) inhibited SCLC growth, altered myc expression, and blocked transition to a treatment-resistant phenotype, a Phase II trial was designed to determine the effects of the combination of RA, cisplatin, and etoposide in patients with SCLC. METHODS: Patients with untreated, extensive stage SCLC were treated with up to 8 cycles of cisplatin, 60 mg/m2, intravenously (i.v.) on Day 1 and etoposide, 120 mg/m2, i.v. on Days 1-3 in addition to up to 1 year of oral RA, 150 mg/m2/day. RESULTS: Of 22 assessable patients 1 had a complete response and 9 had a partial response, for an overall response rate of 45% (95% confidence interval, 24-68%). The median survival was 10.9 months and the 1-year survival was 41%. The median duration of chemotherapy was 6 cycles and the median duration of RA treatment was 2.8 months. Thirteen patients discontinued RA prematurely due to toxicity and only 4 responders were receiving RA at the time of recurrence. Toxicity-limiting RA treatment mainly was comprised of mucocutaneous changes and headaches. CONCLUSIONS: RA at a dose of 150 mg/m2/day was tolerated poorly in combination with cisplatin plus etoposide, leading to early discontinuation of RA in the majority of patients. The hematologic toxicity, response rate, and survival were similar to those associated with cisplatin and etoposide in prior trials. Further studies with more active and less toxic agents will be required to determine the role of retinoids in the treatment of SCLC.  相似文献   
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The nucleus basalis magnocellularis (NBM) is one element in the limbic cortical-ventral striatal circuitry that has been implicated in reinforcement processes. The present study examined the involvement of the cholinergic neurons of the NBM in mediating aspects of cocaine reinforcement. Lesions of the NBM were made by injecting 0.01 M AMPA into the subpallidal basal forebrain. Following 4 days' recovery, rats were implanted chronically with catheters in the jugular vein. In three separate experiments, rats were trained to acquire cocaine self-administration under a FR1 schedule of reinforcement at doses of 0.25, 0.083 and 0.028 mg/injection. A dose-effect function was also determined at the end of the acquisition experiments using five different doses of cocaine (0.009, 0.028, 0.083, 0.25, 0.50 mg/injection) and saline which were presented once daily in a Latin square design. There were no significant differences between groups in the acquisition of cocaine self-administration at any of the three doses studied (0.028, 0.083 and 0.25 mg/injection), although at the lowest dose, lesioned animals responded at greater levels on both active and inactive levers. However, a shift to the left in the cocaine dose-response function was observed revealing that the lesioned group self-administered significantly higher amounts of low doses of cocaine than control rats. These data suggest that the integrity of the NBM is not a critical determinant of the reinforcing effects of cocaine during the acquisition of self-administration of the drug, but that NBM-dependent cholinergic mechanisms may nevertheless interact with the neural substrates mediating the reinforcing properties of cocaine. The data are relevant to recent hypotheses of functional interactions between the dopaminergic system and the cholinergic NBM.  相似文献   
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BACKGROUND: This report describes the complication of pulmonary vein stenosis with resultant severe pulmonary hypertension that developed in 2 patients after successful catheter ablation of chronic atrial fibrillation. METHODS AND RESULTS: Three months after successful catheter ablation of atrial fibrillation, both patients developed progressive dyspnea and pulmonary hypertension. Both were found to have severe stenosis of all 4 pulmonary veins near the junction with the left atrium. Balloon dilation of the stenotic pulmonary veins was performed in these patients, with improvement in dyspnea and pulmonary hypertension. CONCLUSIONS: The complication of pulmonary vein stenosis is potentially life-threatening, and the application of radiofrequency current within the pulmonary veins with standard catheter technology should be avoided. This complication can be treated with balloon dilation, although the long-term course is unknown.  相似文献   
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Estracyt (estramustine phosphate) injected intraperitoneally, 100 mg, per Kg. three days a week for four weeks, retarded growth of the R-3327 tumor in intact rats and in orchiectomized rats given androgen. The growth inhibition was accomplished by reduction of tumor deoxyribonucleic acid concentration and of the activities of acid phosphatase, leucine aminopeptidase, and other hydrolases. Histologic examination revealed cellular necrosis particularly prominent in the orchiectomized, androgen-treated rats. Estracyt did not affect the uptake of 65-Zn in the tumors but markedly reduced the high uptake in the dorsolateral prostate. There was no accumulation of 3H or 14C in the tumors after intravenous administration of 3H, 14C-labeled Estracyt, but the isotope concentrations decreased much in the same way as they decreased in the dorsolateral prostate. The isotopes were retained in the ventral prostate, where their concentrations were approximately twenty times higher than those in the muscle four hours after injection. The results demonstrate the value of the R-3327 tumor in the evaluation of drugs of potential clinical use for the treatment of prostatic cancer. The results also show that Estracyt has an antitumor effect which is not dependent on the antigonadotropic action of the drug.  相似文献   
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Stoichiometric polycrystalline InP, GaAs and (InGa)As were prepared by hydrogen reduction of phosphate and arsenate precursors precipitated from aqueous solution. These ill-defined phosphate and arsenate precipitates were dried and heated at elevated temperatures in a stream of pure hydrogen to produce the phosphides and arsenides. It was found necessary to introduce elemental phosphorus or arsenic in a heated region upstream of the reaction to establish the necessary pressure of P or As in the H2 stream to inhibit the dissociation of the newly formed InP or GaAs.  相似文献   
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