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71.
A novel glutathione-conjugated metabolite of morphine has been isolated from the bile of guinea pigs given morphine. The metabolite was separated by preparative HPLC on a reverse phase column (YMC-GEL C18) using methanol/water (1:4, v/v) as eluate and purified by HPLC on another reverse phase column (mu-Bondapak phenyl) using water/acetonitrile/trimethylamine/acetic acid (150:3:2:1, v/v) as a mobile phase. The unambiguous structure assignment of the metabolite was performed by fast atom bombardment mass spectrometry and 400 MHz fourier transform NMR spectrometric analysis, and it was identified as (8S)-glutathion-S-yl)dihydromorphinone, in comparison with the synthetic morphinone-glutathione adduct.  相似文献   
72.
A case of acute pancreatitis induced by salicylazosulfapyridine (Salazopyrin, SASP) was reported. A 33-year-old man with ulcerative colitis was given SASP. Five weeks later, P-type serum amylase was found to be elevated. The amylase/creatinine clearance ratio (ACCR) and serum lipase were also elevated. There were neither subjective symptoms nor abnormal ultrasound findings in the pancrease. Lymphocyte stimulation test (LST) to SASP was positive. Asymptomatic pancreatitis by SASP was suspected and SASP administration was halted. Afterwards the abnormal data became normal. Readministration of SASP because of relapse caused an episode of pancreatitis similar to the first occasion. LST was negative before SASP intake and became positive after intake. Desensitization to SASP was unsuccessful. LST was negative before attempting desensitization and became positive when the dosage of SASP increased to 100 mg daily. This is the second case of acute pancreatitis reported to be induced by SASP and this is the first case in which LST to SASP was described. To our knowledge, this is also the first case in which a positive LST was described in drug-induced pancreatitis. This case provides evidence for the role of delayed type hypersensitivity in the etiopathogenesis of SASP allergy and of dose-independent drug-induced pancreatitis.  相似文献   
73.
Are cytokines possible mediators of cancer cachexia?   总被引:1,自引:0,他引:1  
The possible role of cytokines in the development of cancer cachexia was reviewed from the literature. Tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6, interferon (IFN)-gamma and leukemia inhibitory factor (LIF) can elicit many but not all host changes seen in cancer cachexia, including loss of appetite, loss of body weight, and the induction of acute-phase protein synthesis. However, these cytokines are not always demonstrated in the circulation of the cancer patients. The inability to detect circulating cytokines may be due to their low rate of production, their short half-life and rapid clearance from plasma, or their mode of action (autocrine or paracrine). Different cytokines are induced to stimulate the same response. This is very different from hormonal regulation, where a hormone acts on a cell directly through a specific receptor without depending on other mediators. Specific antibodies including anti-IFN-gamma, anti-TNF and anti-IL-6 antibodies, as well as the cyclooxygenase inhibitor indomethacin, have been used to reverse cancer cachexia. Overlapping physiologic activities make it unlikely that a single substance is the sole cause of cancer cachexia. It is hoped that further investigation on other cytokines and their possible relationships with hormones will help to clarify the mechanisms of cancer cachexia in the near future.This work was supported by a grant from the Japan-Sweden Foundation in 1991.  相似文献   
74.
Nitric oxide (NO) has recently been shown to modulate the hypothalamic–pituitary–adrenal axis response to interleukin-1β (IL-1β). We measured levels of nitrite (NO2) and nitrate (NO3) in the hypothalamic paraventricular nucleus (PVN) region using an in vivo brain microdialysis technique in conscious rats. Intraperitoneally administered IL-1β produced a significant increase in both NO2 and NO3 levels in the PVN region. We also examined the possible involvement of the abdominal vagal afferent nerves in this effect. In abdominal-vagotomized rats, the increase was significantly attenuated compared to that in sham-operated rats. Our results suggest that the abdominal vagal afferent nerves are involved in intraperitoneally administered IL-1β-induced NO release in the PVN region.  相似文献   
75.
Neurons survive when their activity is maintained. An influential hypothesis on the cellular mechanism underlying this phenomenon is that there is an appropriate range of intracellular Ca2+ concentration ([Ca2+]i) for survival. The rat cerebellar granule neuron in culture serves as the most often used model system for the analysis of activity-dependent survival, since it does not survive unless an excitant (KCl or glutamate) is added to the culture medium. Against the above-mentioned hypothesis, we found in our previous examination no difference between steady-state [Ca2+]i in granule neurons cultured under high KCl (i.e., survival) and low KCl (i.e., death) conditions. In this report, we present the quantitative background of unchanged [Ca2+]i between the two culture conditions. Influx of Ca2+ due predominantly to L-type voltage-dependent calcium channels was higher in high KCl cultures than in low KCl cultures. At the same time, efflux of Ca2+ due to the activity of Ca2+/Na+ antiport was also higher in high KCl cultures. Additionally, we found that the endocytotic activity was greater in high KCl cultures than in low KCl cultures, as monitored by the rate of uptake of horseradish peroxidase added to medium. Since the uptake was blocked by an internal Ca2+ chelator, the increased endocytotic activity in high KCl cultures might be a consequence of the enhanced Ca2+ turnover.  相似文献   
76.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
77.
The initiation site of seizure discharges and the relationship between behavioral manifestations and electroencephalography were investigated in the El mouse, a hereditary epilepsy model. The chronic depth electrodes were implanted stereotaxically into the frontal cortex, parietal cortex, temporal cortex, hippocampus, striatum, amygdaloid complex, non-specific nuclei of thalamus and substantia nigra. Electrical activities were recorded in freely moving condition with use of the buffer amplifier devised in the laboratory and behaviors were monitored simultaneously. Seizure spike discharges started in the parietal cortex and spread out into other brain areas. When the hippocampus was involved, the tonic convulsion occurred behaviorally. The paper describes the first direct evidence of the initiation and propagation of seizure discharges in the brain of El mouse.  相似文献   
78.
Radiographs were examined in 35 patients who had had posterior decompression without fusion of the lumbar spine. Spondylolysis was found in 10 patients. Segmental range of motion, degree of vertebral slippage and width of decompression were analyzed by radiography. There was greater vertebral slippage after surgery in patients with postoperative spondylolysis than in those without spondylolysis. We conclude that excessive bony decompression may cause postoperative spondylolysis.  相似文献   
79.
A multiclinic study of gentamicin (GM) given by intravenous drip infusion was carried out by the Gentamicin Pediatric Study Group. The results are summarized as follows: 1. Upon intravenous drip infusion of GM at a dose range of 2.0-2.5 mg/kg over a period of 0.5-1 hour, therapeutically effective serum concentrations of 4-12 micrograms/ml were obtained. These values are similar to reported values in previous studies using GM intramuscular injection. 2. High urinary concentrations were observed up to 6 hours after administration, and the urinary recovery rate was approximately 60%. 3. Of a total of 142 cases collected, 117 cases were evaluated. Efficacy rates by diseases were: 100% in pneumonia (30/30), 98.3% in urinary tract infections (59/60), and 92.3% in other infections (skin and soft tissue) (12/13), with an overall efficacy rate of 94.9% (including 77 "excellent" cases). 4. Bacteriological examinations showed high eradication rates with the use of GM; i.e., 80% with Staphylococcus aureus (8/10), 60% with Pseudomonas aeruginosa (3/5), 100% with Haemophilus influenzae (7/7) and 97.8% with Escherichia coli (44/45), achieving an overall eradication rate of 92.4%. In mixed infections, the eradication rate was 85.7% (6/7). 5. No ototoxicity, nephrotoxicity or allergic reactions was observed. Abnormal laboratory findings observed were: GOT elevation in 3.1% of cases, GPT elevation in 3.9%, platelet increase in 1.5% and eosinophil increase in 0.8%, thus an overall rate of the appearance of abnormality was 5.6%. The above results indicate that an intravenous drip infusion of GM is a useful method for treating infections in pediatrics.  相似文献   
80.
Y Ishida  S Ishiuchi 《Gan no rinsho》1989,35(11):1205-1212
Three-tiered system dividing supratentorial astrocytic neoplasms into the astrocytoma, anaplastic (malignant) astrocytoma and the glioblastoma multiforme has been widely used. However, the pathology of anaplastic astrocytoma is defined in different ways according to different classifications. A total of 42 biopsy specimens from 35 cases diagnosed as anaplastic astrocytoma were reviewed pathologically and their features were correlated with a follow-up clinical study to discuss the prognostic usefulness of the subdivision of anaplastic astrocytoma. In WHO classification, anaplastic astrocytoma is defined as "astrocytoma containing areas of anaplasia". Follow-up study of 7 cases with the histology as such revealed that 5 cases had survived more than one year and seven months. The other 28 cases showed a varied histology and were subclassified into an astrocytoma in which moderately anaplastic cells are found throughout the tumor, an astrocytoma formed by anaplastic fusiform cells, an astrocytoma composed of predominantly rounded anaplastic cells, and a pleomorphic astrocytoma with or without intracytoplasmic hyaline inclusions. A follow-up study of cases with these types of astrocytoma disclosed death in 15 cases within one year and 7 months following the first surgery and that three cases displayed typical histological features of glioblastoma at autopsy. It is considered that there would be a considerable overlap between the group of anaplastic astrocytoma and that of glioblastoma, if we use the term "anaplastic astrocytoma" in a broader category.  相似文献   
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