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101.
Many imaging methods can be used to detect pheochromocytoma, but some tumors are not detected with conventional modalities. To explore the possible usefulness of positron emission tomography (PET) after administration of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) to localize pheochromocytoma in patients with false-negative scintigrams obtained after administration of metaiodobenzylguanidine (MIBG), FDG was administered and PET was performed in two adult patients with pheochromocytomas that had never been localized despite administration of MIBG. In both patients, images were obtained dynamically for 50 minutes; then a limited truncal sequence was performed. PET enabled correct localization of the tumors. In patient 1, a tumor that had not been detected for 21 years was localized in the middle mediastinum; in patient 2, a pheochromocytoma was detected in the right adrenal gland. PET performed after administration of FDG may be useful for localization of pheochromocytomas that do not accumulate MIBG.  相似文献   
102.
The primary objective of this study was to evaluate the electrophysiologic effects of large-dose propofol, used as the sole anesthetic in patients with epilepsy. Nine patients with medically intractable complex partial epilepsy undergoing a three-stage approach to the surgical management of epilepsy were recruited. State I involved placement of the intracranial electrode array, while Stage II consisted of extraoperative localization of the seizure focus. The patients were studied during induction of anesthesia for Stage III (removal of electrodes and resection of seizure focus). Unpremedicated patients were induced with a propofol infusion (0.5 mg.kg-1.min-1) until one of the following occurred: 1) electrical seizure activity, 2) burst suppression, or 3) total dose of 10 mg/mg. Electrocorticography (ECoG) was recorded continuously during this period. Two patients were excluded from the study after experiencing delayed awakening after the Stage I procedure. Both had received propofol along with other anesthetics. No ECoG evidence of seizure activity was detected in the seven patients completing the study. Burst suppression was attained in six patients using a mean dose of 5.7 mg/kg +/- 2.6. We conclude that large dose propofol alone does not trigger electrical epileptiform activity on the ECoG of seizure patients.  相似文献   
103.
BACKGROUND: The New Approaches to Coronary Intervention (NACI) voluntary registry was designed to study the use, safety, and efficacy of new percutaneous transluminal interventional devices including directional coronary atherectomy, the transluminal extraction catheter, the rotablator, the Palmaz-Schatz stent, the Gianturco-Roubin stent, the Advanced Interventional Systems (AIS) laser, and the spectranetics laser. METHODS: To date, more than 3800 consecutive patients treated for the first time with a new device at 41 centers have been entered into the registry. Complete detailed information about the patient, lesions, device characteristics, reasons for device selection, and procedural data, such as adjunctive use of conventional balloon angioplasty (PTCA), was available for the first 2835 patients. RESULTS: The registry shows that 88% of the 3233 attempts with a new device were intended as a definitive treatment of target lesions, frequently in combination with adjunctive PTCA. The remaining 12% of attempts with a new device were unplanned, prompted by unexpected complications, unsuccessful attempts, or suboptimal results with PTCA. Although there was some overlap in the indications for selecting a given interventional device, the variation from device to device was sufficiently large to caution users against any direct comparison of either safety or efficacy between devices without careful attention to the differences in baseline patient and lesion characteristics, treatment plans, and the circumstances of device use. CONCLUSION: This report provides the first comprehensive overview of how new interventional devices are currently being used in the treatment of coronary artery lesions at the 41 centers participating in the NACI registry.  相似文献   
104.
Zucchini, Cucurbita pepo L., infested with 22-h-old eggs of Bactrocera cucumis (French) were completely disinfested using a vapor heat treatment of 45 degrees C with > 94% RH for 30 min. An estimated total of 178,219 eggs (22 h old) was treated without survivors, thus achieving probit 9 mortality. Twenty-two-h-old eggs were significantly more tolerant of heat than first, second, or third instars. All treatments were done in a Sanshu model EHK-1000B vapor heat treatment system.  相似文献   
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Muscarinic agonists were tested in two models indicative of clinical antipsychotic activity: conditioned avoidance responding (CAR) in rats and inhibition of apomorphine-induced climbing in mice. The standard muscarinic agonists oxotremorine and pilocarpine were both active in these tests but showed little separation between efficacy and cholinergic side effects. Structure-activity relationships of the alkylthio-1,2,5-thiadiazole azacyclic type muscarinic partial agonists are shown, revealing the exo-6-(3-propyl/butylthio-1,2, 5-thiadiazol-4-yl)-1-azabicyclo[3.2.1]octane analogues (4a,b and 9a, b) to be the most potent antipsychotic agents with large separation between efficacy and cholinergic side effects. The lack of enantiomeric selectivity suggests the pharmacophoric elements are in the mirror plane of the compounds. A model explaining the potency differences of closely related compounds is offered. The data suggest that muscarinic agonists act as functional dopamine antagonists and that they could become a novel treatment of psychotic patients.  相似文献   
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Receptor tyrosine kinases of the EPH class have been implicated in the control of axon guidance and fasciculation, in regulating cell migration, and in defining compartments in the developing embryo. Efficient activation of EPH receptors generally requires that their ligands be anchored to the cell surface, either through a transmembrane (TM) region or a glycosyl phosphatidylinositol (GPI) group. These observations have suggested that EPH receptors can transduce signals initiated by direct cell-cell interaction. Genetic analysis of Nuk, a murine EPH receptor that binds TM ligands, has raised the possibility that these ligands might themselves have a signalling function. Consistent with this, the three known TM ligands have a highly conserved cytoplasmic region, with multiple potential sites for tyrosine phosphorylation. Here we show that challenging cells that express the TM ligands Elk-L or Htk-L with the clustered ectodomain of Nuk induces phosphorylation of the ligands on tyrosine, a process that can be mimicked both in vitro and in vivo by an activated Src tyrosine kinase. Co-culture of cells expressing a TM ligand with cells expressing Nuk leads to tyrosine phosphorylation of both the ligand and Nuk. These results suggest that the TM ligands are associated with a tyrosine kinase, and are inducibly phosphorylated upon binding Nuk, in a fashion reminiscent of cytokine receptors. Furthermore, we show that TM ligands, as well as Nuk, are phosphorylated on tyrosine in mouse embryos, indicating that this is a physiological process. EPH receptors and their TM ligands therefore mediate bidirectional cell signalling.  相似文献   
110.
This study evaluates the efficacy of ultrasound guided percutaneous biopsy using an 18 gauge automated side-cutting needle in the diagnosis of small (< or = 3 cm) focal hepatic lesions. 137 consecutive percutaneous biopsies of 131 different small (< or = 3 cm) focal hepatic lesions were included. 11 biopsies were performed on lesions of < or = 1 cm in diameter, 56 were on lesions 1.1-2 cm in size and 70 on lesions 2.1-3 cm in size (average 2.3 +/- 0.7 cm; median 2.3 cm; range 0.7-3 cm). The biopsy specimen was sufficient for diagnosis in 135 cases (98.5%). The sensitivity for diagnosing malignancy was 96.4%; specificity was 100%, positive and negative predictive values were 100% and 94.6%, respectively; accuracy was 97.8%. There was no statistically significant difference in the diagnostic efficacy for lesions of different pathology and size. No significant post-biopsy complication occurred. It is concluded that the 18 gauge Temno needle is safe and effective in diagnosing small hepatic lesions.  相似文献   
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