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51.
52.
In these studies, the physical dependence liability of butorphanol, a mixed 'agonist/antagonist' opioid analgesic, was compared to that of morphine. Male, Sprague-Dawley rats received i.c.v. infusions of saline (1 microliter/h), or an equimolar dose of butorphanol or morphine (52.3 nmol/h) for 3 days. The physical dependence liabilities of these two compounds were then compared by assessing both behavioral withdrawal signs and weight loss following naloxone-precipitated withdrawal. Body weight loss was also evaluated following abrupt (cessation of infusion) withdrawal from butorphanol or morphine. In animals receiving i.c.v. infusions of butorphanol or morphine, naloxone administration (5 mg/kg s.c.) induced an equivalent degree of body weight loss compared to saline-treated animals. In addition, the ED50 of naloxone to produce wet shakes, escape behavior, teeth chattering, urination and defecation was equivalent in rats receiving butorphanol or morphine. Infusions of butorphanol or morphine also produced an equivalent degree of weight loss in animals undergoing abrupt withdrawal. These results demonstrate then that a substantial degree of physical dependence had developed in rats which received a large dose of butorphanol. 相似文献
53.
Molecular and mechanical property changes during aging of bone cement in vitro and in vivo 总被引:2,自引:0,他引:2
The changes in mechanical properties and free radical concentration of curing Simplex P Radiopaque Bone Cement in vivo and in vitro conditions were studied. Samples were prepared so that each in vivo sample that cured and aged in the canine femoral intramedullary cavities had an in vitro counterpart that was cured and aged in a constant-temperature saline bath at 37 degrees C. An electron paramagnetic resonance (EPR) spectrometer was used to measure the growth and decay (curing) of polymerization radicals. The results of EPR measurements showed that the curing (disappearance of free radicals) of in vivo samples takes a much longer time (more than 4 weeks) than in vitro curing (less than 2 weeks). The mechanical tests indicate that, whether aged in vivo or in vitro, the strength increased rapidly for the first 1-2 weeks and then slight increases were seen for up to 6 months. 相似文献
54.
Beth Hoskins Dudley F. Peeler Kathia Lawson Angie M. Barnes Ing K. Ho 《Brain research bulletin》1991,27(2):279-281
The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents. 相似文献
55.
Ceftriaxone-associated gallbladder sludge. Identification of calcium-ceftriaxone salt as a major component of gallbladder precipitate 总被引:5,自引:0,他引:5
Ceftriaxone, a third-generation cephalosporin, is partially excreted into bile. With its clinical use, the formation of gallbladder sludge detected by ultrasonography has been reported. Four surgical specimens were examined and no gallstones were found. Instead, fine precipitates of 20-250 microns were present. Microscopically, there was a small number of cholesterol monohydrate crystals and bilirubin granules among an abundant amount of granular-crystalline material that was not morphologically cholesterol monohydrate crystals. The chemical composition of the precipitates (n = 4) was determined. There was a small amount of cholesterol (1.7% +/- 0.8%) and bilirubin (13.9% +/- 0.74%). The major component of the precipitate was a residue. On further analysis using thin-layer chromatography, high-performance liquid chromatography, and electron microprobe analysis, the residue was identified as a calcium salt of ceftriaxone. The residue also had identical crystal morphology and chromatographic elution profile as authentic calcium-ceftriaxone standards. It is concluded that ceftriaxone, after excretion and being concentrated in the gallbladder bile, can form a precipitate. The major constituent has been identified as a ceftriaxone-calcium salt. 相似文献
56.
57.
J D Lee K H Shin S N Cho J S Shin M G Lee W I Yang C Y Park H S Yoo J T Lee O D Awh 《European journal of nuclear medicine》1992,19(12):1011-1015
Immunoscintigraphy with radiolabelled monoclonal antibodies is widely used to detect solid tumours, but only a few trials have been carried out concerning the specific in vivo localization of an inflammatory process. The purpose of this study was to investigate the detectability of tuberculous foci utilizing this method with radiolabelled bacillus Calmette-Guérin (BCG)-specific F(ab')2 in rabbits. All of the tuberculous lesions (n = 8) were clearly visualized on serial scintigraphy for up to 48 h after injection of the antibody. Immunohistochemical and Ziel-Neelson staining of the tuberculous lesions confirmed the presence of the tuberculous antigens and bacilli. It failed to demonstrate any sustained retention of the BCG-specific antibody fragment in the control group with syphilitic orchitis (n = 2). Therefore, the specific in vivo localization of tuberculosis is feasible by immunoscintigraphy. 相似文献
58.
H D Lee C O Suh W H Jung K K Oh H B Park H S Chi B R Kim J S Min 《Yonsei medical journal》1992,33(3):272-276
This is the first preliminary report among two consecutive papers. Partial mastectomy(PM), axillary lymph node dissection(AD) and radiotherapy (RT) were performed on seventeen operable breast cancer patients who had been admitted from April 1991 to March 1992 to the department of surgery, Yongdong Severance Hospital for improved cosmetic appearance and better survival rate. Of seventeen patients, 47% were T1 lesion and 76% were stage I and II. Extensive intraductal component(EIC) within or around the tumor was also analyzed. Twenty nine per cent of the patients were EIC positive. The mean number of axillary lymph nodes was 21.5 after PM with AD and 20.5 after mastectomy. For radiotherapy, 4,500 rad was delivered to the breast parenchyma and 1,600 rad of boost to the primary tumor site using the electron beam method after surgery. All patients have since been living well without any local recurrence and were satisfied with breast preservation for the one-year follow-up period. We concluded that the PM, AD and RT can be another surgical treatment modality of breast cancer. A longer follow-up data will be followed on the second paper. 相似文献
59.
60.