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71.
Ramsay D Marshall M Song S Zimmerman M Edmunds S Yusoff I Cullingford G Fletcher D Mendelson R 《Australasian radiology》2004,48(2):154-161
Pancreatic malignancy can be staged by a number of different investigations, either alone or in combination. The purpose of the present study was to compare the use of endoscopic ultrasound, CT and mangafodipir trisodium-enhanced MRI for the staging of pancreatic malignancy, particularly with respect to determining resectability prior to surgery. Twenty-seven patients referred for the investigation of a suspected pancreatic malignancy were entered into the trial. All patients had contrast-enhanced CT, gadolinium and mangafodipir trisodium-enhanced MRI, and endoscopic ultrasound (EUS). Images were assessed for nodal staging, tumour staging and resectability for each investigation, and the results compared with findings at surgery. The results for the accuracy of MRI, CT and EUS, in detecting T4 disease versus T3 or lower was 78, 79 and 68%, respectively; nodal involvement was 56, 63 and 69%, respectively; and overall resectability (including the T stage, presence of involved nodes and metastases) was 83, 76 and 63%, respectively. There was no significant difference demonstrated between the three tests. The present study suggests that for patients referred for investigation and staging of pancreatic malignancy, EUS and MRI scanning convey little advantage over contrast-enhanced CT. Furthermore, although mangafodipir trisodium improved the conspicuity of pancreatic tumours, it has little influence on T staging. 相似文献
72.
OBJECTIVE: Buprenorphine and buprenorphine/naloxone combinations are effective pharmacotherapies for opioid dependence, but doses are considerably greater than analgesic doses. Because dose-related buprenorphine opioid agonist effects may plateau at higher doses, we evaluated the pharmacokinetics and pharmacodynamics of expected therapeutic doses. DESIGN: The first experiment examined a range of sublingual buprenorphine solution doses with an ascending dose design (n = 12). The second experiment examined a range of doses of sublingual buprenorphine/naloxone tablets along with one dose of buprenorphine alone tablets with a balanced crossover design (n = 8). PARTICIPANTS: Twenty nondependent, opioid-experienced volunteers. METHODS: Subjects in the solution experiment received sublingual buprenorphine solution in single ascending doses of 4, 8, 16 and 32 mg. Subjects in the tablet experiment received sublingual tablets combining buprenorphine 4, 8 and 16 mg with naloxone at a 4 : 1 ratio or buprenorphine 16 mg alone, given as single doses. Plasma buprenorphine, norbuprenorphine and naloxone concentrations and pharmacodynamic effects were measured for 48-72 hours after administration. RESULTS: Buprenorphine concentrations increased with dose, but not proportionally. Dose-adjusted areas under the concentration-time curve for buprenorphine 32 mg solution, buprenorphine 1 6 mg tablet and buprenorphine/naloxone 16/4 mg tablet were only 54 +/- 16%, 70 +/- 25% and 72 +/- 17%, respectively, of that of the 4 mg dose of sublingual solution or tablet. No differences were found between dose strengths for most subjective and physiological effects. Pupil constriction at 48 hours after administration of solution did, however, increase with dose. Subjects reported greater intoxication with the 32 mg solution dose, even though acceptability of the 4 mg dose was greatest. Naloxone did not change the bioavailability or effects of the buprenorphine 16 mg tablet. CONCLUSION: Less than dose-proportional increases in plasma buprenorphine concentrations may contribute to the observed plateau for most pharmacodynamic effects as the dose is increased. 相似文献
73.
Pinchoff RJ Kaufman SS Magid MS Erdman DD Gondolesi GE Mendelson MH Tane K Jenkins SG Fishbein TM Herold BC 《Transplantation》2003,76(1):183-189
BACKGROUND: The purpose of this study was to determine the prevalence of adenoviral infection in pediatric small bowel transplantation (SBT) recipients, examine risk factors for progression to histologic disease, and examine the impact of adenovirus on outcome. METHODS: Beginning in July 2000, all SBT recipients had viral cultures for adenovirus, cytomegalovirus (CMV), and herpes simplex virus (HSV) obtained routinely during graft biopsies. The medical records were retrospectively reviewed for frequency and site of viral culture, types and doses of immunosuppressive drugs, episodes of rejection, histology of allograft biopsies, and other infections. Adenoviral isolates were typed by polymerase chain reaction and type-specific neutralization assays. RESULTS: All 14 SBT recipients who met enrollment criteria had evidence of adenoviral infection (intestinal graft, 13; liver graft, 1). Eight of 14 developed histologic disease with identifiable adenoviral intranuclear inclusions. In contrast, CMV enteritis was identified in only one patient, who subsequently also developed adenoviral disease. No other viruses were detected. Adenoviral cultures were first positive within 30 days of transplant in nine. Patients with histologic disease were more likely than those without to have received intensive corticosteroid therapy (P<0.007), had virus isolated from more than one site (P=0.03), and had persistent positive cultures (P<0.01). CONCLUSIONS: Adenovirus was commonly isolated from children undergoing intestinal transplantation. Progression to disease may be associated with more intensive immunosuppressive therapy and inability to clear virus. 相似文献
74.
BACKGROUND: Concurrent use of cocaine and alcohol results in formation of a cocaine homolog and metabolite-cocaethylene. METHODS: To characterize cocaethylene pharmacology, ten paid volunteer subjects were given deuterium-labeled (d(5)) cocaine (0.3, 0.6, and 1.2 mg/kg and cocaine placebo) by a 15-min constant rate intravenous injection 1 h after a single oral dose of ethanol (1 g/kg) or ethanol and cocaine placebo using a double-blind, crossover design. Six of the same volunteers subsequently received a 1.2 mg/kg dose of cocaine alone. A small (7.5 mg) nonpharmacologically active dose of deuterium-labeled cocaethylene-d(3) was concurrently administered with the cocaine to enable calculation of absolute cocaethylene formation and clearance. Plasma and urine cocaine, cocaethylene, and benzoylecgonine concentrations, physiologic and subjective effects were measured. RESULTS: When co-administered with ethanol, 17+/-6% (mean+/-S.D.) of the cocaine was converted to cocaethylene. Cocaethylene peak plasma concentrations and AUC increased proportionally to the cocaine dose. Ethanol ingestion prior to cocaine administration decreased urine benzoylecgonine levels by 48% and increased urinary cocaethylene and ecgonine ethyl ester levels. Subjects liked and experienced more total intoxication after the combination of cocaine and ethanol than after either drug alone. CONCLUSIONS: In the presence of ethanol, the altered biotransformation of cocaine resulted in 17% of an intravenous cocaine dose being converted to cocaethylene and relatively lower urinary concentrations of benzoylecgonine. 相似文献
75.
Harris D Jones RT Shank R Nath R Fernandez E Goldstein K Mendelson J 《Journal of addictive diseases》2000,19(3):89-103
In order to assess the relationships between medical marijuana users' reasons for use, side effects, and drug use patterns, 100 participants were recruited from the San Francisco Cannabis Cultivator's Club. Users, averaging 14 years pre-illness use, perceived marijuana to be more effective than other treatments and to have less severe side effects. Urine drug assays showed recent use of other drugs, particularly stimulants. History of substance abuse or dependence and other psychiatric disorders was common. Those with greater past dependence on other drugs thought marijuana to be more effective but also reported worse side effects and quality of life. Quality of life was associated more with marijuana side effects rating than effectiveness. Patients reported potentially serious marijuana side effects on some questionnaires but not others. Inconsistencies in reporting made interpretation of results difficult. Physician supervision of medical marijuana use would allow more effective monitoring of therapeutic and unwanted effects, some unrecognized by patients. 相似文献
76.
77.
Louis Mendelson David Cook Mario Cruz-Rivera Sherahe Fitzpatrick Joseph A Smith 《The Journal of asthma》2002,39(3):227-237
A retrospective analysis, based on a randomized, placebo-controlled, 12-week study in children 6 months to 8 years of age with persistent asthma, was performed to compare the efficacy and safety of budesonide inhalation suspension 0.25 mg and 0.5 mg twice daily vs. placebo in children < 4 and > or = 4 years of age. Both age groups demonstrated significant (p < or = 0.050) improvement in nighttime and daytime asthma symptom scores and decreased bronchodilator use compared with placebo. In addition, the safety profile of twice-daily budesonide inhalation suspension was favorable in both age groups. 相似文献
78.
J H Mendelson N K Mello S K Teoh J G Lloyd-Jones J M Clifford 《Journal of clinical psychopharmacology》1989,9(2):105-109
The effects of parenterally-administered buprenorphine and simultaneous injection of naloxone was evaluated in six healthy adult males. Each subject was studied on six occasions, an average of 10 days apart, and received either two simultaneous intramuscular injections of saline, buprenorphine 0.3 mg and saline, or buprenorphine 0.3 mg and 0.6 mg, 0.45 mg, 0.3 mg, or 0.15 mg of naloxone. Simultaneous injection of buprenorphine 0.3 mg and saline resulted in an average increase in plasma prolactin above baseline levels of approximately 10 and 25 ng/ml, 30 and 55 minutes after injection. Buprenorphine-induced stimulation of plasma prolactin levels was statistically significantly greater than basal prolactin values (p less than 0.01). When 0.6 mg of naloxone was simultaneously injected with 0.3 mg buprenorphine, peak plasma prolactin levels were significantly lower (p less than 0.05) than prolactin values after administration of 0.3 mg buprenorphine and saline. Simultaneous injection of 0.45 mg naloxone and 0.3 mg buprenorphine also resulted in a significant attenuation (p less than 0.05) of buprenorphine-stimulated prolactin levels. Injection of 0.3 mg or 0.15 mg of naloxone did not inhibit prolactin stimulation produced by buprenorphine 0.3 mg. These findings demonstrate a dose-effect relationship between naloxone concentration and suppression of the increase in plasma prolactin levels produced by administration of buprenorphine 0.3 mg. As prolactin stimulation occurs shortly after opioid agonist administration and is temporally concordant with the rapid induction of pharmacologic reinforcement associated with opiate abuse, naloxone added to buprenorphine parenteral preparations may reduce the abuse potential of buprenorphine. 相似文献
79.
We report a patient with recurrent ovarian carcinoma who developed a mediastinal mass due to extravasated Intralipid hyperalimentation fluid secondary to catheter induced occlusion of the left innominate vein. 相似文献
80.