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91.
After bolus intravenous dosing of d-tubocurarine (d-TC) to rats, the twitch heights of the tibialis anterior muscle indirectly stimulated were followed, and its decrease was defined as pharmacologic response of d-TC. The relation between dose and response intensity was found to be well described with Hill's equation. According to a theory proposed by Smolen, Hill's equation was also applicable to the biophase d-TC concentration-response relation; the time courses of the relative biophase d-TC concentration indicated linear kinetics with dose levels 0.15 mg/kg and the occurrence of dose-dependent disposition with 0.30 mg/kg. After bolus i.v. dosing of3H-d-TC, plasma d-TC concentration obeyed a dose-independent two compartment model with doses 0.15mg/kg, but not with 0.30 mg/kg. This finding matched the above estimated with pharmacologic data. The active metabolite was not found in plasma and urine. The extent of d-TC plasma protein binding was independent of the wide range of plasma levels and its mean (±SD) value was 30.5 (±3.8). Plasma d-TC levels and pharmacologie response intensity were well correlated by Hill's equation and a three compartment model (the general two and the biophase compartments) in the dose range 0.15 mg/kg.This work was presented at the First Japanese-American Symposium on Pharmacokinetics and Biopharmaceutics, Tokyo, July 1981, which was held in memory of Dr. Sidney Riegelman.  相似文献   
92.
The clinical efficacy, dose-response relationship, and safety of TRH-T (thyrotropin releasing hormone tartrate) were assessed in 290 patients with spinocerebellar degeneration (SCD) in a 2-week, double-blind study using placebo as control. 254 patients satisfied the criteria for inclusion in evaluation of the drug efficacy. The patients were treated with TRH-T in an intramuscular dose of 2 mg, 0.5 mg or 0 mg (placebo) as TRH once a day for 2 weeks. Clinical responses to these treatments were evaluated 3 times: at the end of weeks 1 and 2 of treatment and a week after the end of treatment. The results of "global improvement rating" as well as those of "ataxia improvement rating" showed that both 2 mg and 0.5 mg TRH-T treatments were significantly superior to placebo treatment in patients with predominantly cerebellar form of SCD. The effect was well maintained a week after the end of the 2-week treatment in the patients who were given TRH-T in daily dose of 2 mg and showed improvement at the end of treatment. The results of "improvement rating of each symptom" revealed that 2 mg treatment was significantly more effective than placebo for disorders of standing, gait, speech and writing. In the patients who had no pyramidal involvement or disorder of deep sensation, the drug efficacy and dose-response relationship were evident. Adverse reactions to the drug such as headache, feeling febrile and nausea were observed in 50% of the patients on 2 mg treatment, in 38% of those on 0.5 mg treatment and in 21% of those on placebo patient, however, discontinued treatment because of adverse reactions.  相似文献   
93.
Synthetic alpha-human atrial natriuretic peptide (alpha-hANP), 1 micrograms/kg, was intravenously given to 16 cirrhotic patients with ascites and 9 control subjects (CS) to investigate major factors responsible for sodium retention and refractory ascites. The following parameters were measured before and after alpha-hANP administration; such as lithium clearance (CLi) as an index of fluid delivery to the distal tuble, mean arterial pressure (MAP), urinary sodium excretion rate (UNaV), urine volume (V), glomerular filtration rate (GFR), effective renal plasma flow (ERPF), plasma renin activity (PRA), plasma aldosterone concentration (PAC), urinary excretion of prostaglandin (PG)E2, 6-keto-PGF1 alpha (6-k-PGF1 alpha), and thromboxane B2 (TxB2). Patients were divided following alpha-hANP administration into 2 groups as "good responders (GR)" and "poor responders (PR)", in which GR was defined as the group showing 2-fold-increase in UNaV. In contrast, PR had significant lower MAP (71.8 +/- 5.04 mmHg), GFR (21.3 +/- 3.90 ml/min), ERPF (158.0 +/- 43.8 ml/min), FELi (CLi/GFR; 12.6 +/- 1.26%), and higher PRA (8.72 +/- 0.99 ng/ml/h) and PAC (12.2 +/- 3.13 ng/dl) than GR. GR demonstrated almost same natriuretic response as CS with an increase of GFR and renal PGs synthesis, and a decrease of FELi despite reduction in blood pressure. However, alpha-hANP did not suppress PRA, PAC, and distal tubular reabsorption of sodium (FDRNa = 1-FENa/FELi) in cirrhotic patients, whereas suppressed in CS. UNaV correlated with FELi (r = 0.687, p = 0.01) and GFR (r = 0.777, p = 0.01). PRA correlated with FELi r = 0.669, p = 0.015), GFR (r = -0.634, p = 0.018), and MAP (r = 0.858, p = 0.001) only in cirrhosis. These results therefore indicated that hypotension caused by hemodynamic alteration and extremely stimulated renin release might effect on proximal tubular sodium reabsorption and GFR, leading to sodium retention and diuretic resistance in cirrhosis.  相似文献   
94.
95.
The role of the sentinel lymph node in gastrointestinal cancer   总被引:38,自引:0,他引:38  
Evaluation of the clinical significance of the sentinel node concept in GI cancer has just begun. The authors' preliminary data, using intraoperative radiation techniques and the gamma probe, suggest that it is worthwhile to continue the evaluation of this procedure to determine its role in an accurate staging and a minimally invasive approach to GI cancers.  相似文献   
96.
97.
Domino liver transplantation from a living related donor   总被引:4,自引:0,他引:4  
BACKGROUND: Although domino liver transplantations (OLT) from cadaveric donors have been performed in about 50 cases since 1995, only one case in the Japanese literature has been reported on a domino OLT from a living related donor. The difficulties of the later surgery lie in the small size of the graft volume and the short length of the vascular cuffs in the graft. METHODS: The left lobe graft was procured from a 43-year-old younger brother of a familial amyloidotic polyneuropathy (FAP) patient. Next, the left lobe graft (510 g, 44% of the estimated standard liver volume of the FAP patient) was implanted into the 48-year-old female FAP patient. At surgery for the FAP patient, a sufficient length of the vascular cuffs was secured by an extended left lobe resection, although the right lobe graft was able to maintain sufficient vascular cuffs. The right lobe graft (720 g, 54% of the recipient's estimated standard liver volume) was then implanted in the 43-year-old male patient with liver cirrhosis and hepatocellular carcinoma (stage IV-A). RESULTS: The two recipients were discharged from the hospital 1 month after OLT. At 7 months after OLT, they are both doing well and the domino recipient is free of any tumor recurrence. CONCLUSION: A domino OLT from the living related donor can therefore be done safely when careful attention is paid to the graft volume and the length of the vascular cuffs for anastomosis.  相似文献   
98.
AIM: The objective of this study was to examine the effects of perioperative administration of ulinastatin, or urinary trypsin inhibitor (UTI), on inflammatory cytokines and acute-phase proteins induced by inflammatory cytokines in patients who had undergone hepatic resection. METHOD: Twenty patients admitted to the hospital for hepatic resection were equally randomized to one of two groups: the UTI group, those who were administered perioperative UTI, and the control group. RESULTS: The UTI group had no adverse effects from using UTI. Production of serum interleukin-6 (IL-6) tended to be attenuated in the UTI group when compared with the control group. Moreover, the UTI group had significantly decreased positive acute-phase C-reactive protein (p < 0.05) and significantly increased negative acute-phase protein prealbumin and retinol-binding protein (p < 0.05). Serum IL-6 levels significantly correlated with serum C-reactive protein levels on postoperative day 1 (r = 0.70, p < 0.01). CONCLUSION: These results suggest that perioperative administration of UTI might deserve further assessment for use in modulating acute-phase responses without adverse effects in patients who have undergone hepatic resection.  相似文献   
99.
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs.  相似文献   
100.
We report a case of anal canal cancer in a 65-year-old woman who had complained of bloody stool. Physical examination revealed a 2.5 cm ulcerated tumor in the anterior wall of the anal canal astride the dentate line. Histological examination of biopsy specimens confirmed the diagnosis of moderately differentiated squamous cell carcinoma. Chemoradiation therapy included whole pelvic irradiation amounting to 4140 cGy followed by conformal boost irradiation of 2000 cGy and 5-fluorouracil div 750 mg/24 hr 3 days, mitomycin C iv 10 mg day 1, and cisplatinum div 50 mg day 2. Six weeks later the tumor had completely regressed, and there was no evidence of recurrence 21 months later. Her anorectal function was retained.  相似文献   
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