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81.
82.
Lee YJ Nam SW Seo DW Ahn SH Ko YK Sung DS Han JW Hong SY Lee HW 《Archives of pharmacal research》1997,20(3):239-246
In the present study, liver regeneration rate (%) was increased up to 70% 3 days after partial hepatectomy (PH). Nitric oxide
synthase (NOS) activity in liver tissue as well as serum nitrite/nitrate content had no timed response, revealing no significant
difference between shamoperated and partially hepatectomized rat liver. Contents of free methylarginines in liver tissue were
increased biphasically in a time-dependent manner after PH. However, those in serum did not exhibit the same patterns as in
liver. Taken together, the results suggest that NG-monomethyl-L-arginine (MMA) and NG, NG-dimethylarginine (DMA) play a role in inhibiting nitric oxide (NO) synthesis in regenerating rat liver because the increase
of their contents was synchronized with NOS expression. 相似文献
83.
The hydrolysis of metampicillin to ampicillin was investigated using high performance liquid chromatography. We developed the simultaneous determination of metampicillin and ampicillin using a Zorbax CN column and 5% acetonitrile and 8% methanol in 0.02 M phosphate buffer (pH 7.0) as mobile phase. Metampicillin was hydrolyzed to ampicillin with half life of 41.5 min at physiological pH and temperature. In acidic pH, metampicillin was rapidly hydrolyzed to ampicillin within a chromatographic separation. 相似文献
84.
When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin. 相似文献
85.
Effect of biphenyl dimethyl dicarboxylate on the cellular and nonspecific immunosuppressions by ketoconazole in mice 总被引:4,自引:0,他引:4
The effect of biphenyl dimethyl dicarboxylate (PMC) on the cellular and nonspecific immunosuppressions by ketoconazole (KCZ) was investigated in ICR mice. PMC at a dose of 6 mg/kg was administered orally to mice daily for 14 consecutive days. KCZ was suspended in RPMI 1640 medium and orally administered at 160 mg/kg/day 2 hrs after the administration of PMC. Immune responses of the delayed-type hypersensitivity (DTH) reaction to sheep red blood cells (SRBC), phagocytic activity and natural killer (NK) cell activity were evaluated. DTH reaction to SRBC was enhanced to normal level by the combination of PMC and KCZ, compared with treatment of KCZ alone. In the combination of PMC and KCZ, as compared with the treatment of KCZ alone, there were also significant increases in activities of natural killer (NK) cells and phagocytes along with circulating leukocytes. These findings indicate that PMC shows a significant restoration from the immunotoxic status induced by KCZ. 相似文献
86.
Aliphatic esters of protocatechuic acid (PA,1), vanillic acid (VA,9) and gallic acid (GA,18) were prepared and their anti-thrombotic effects were evaluated in the mouse model of thrombosis. The aliphatic groups included methyl, ethyl,n-propyl,i-propyl,n-butyl,i-butyl,n-amyl and cyclohexyl.n-Amyl ester of PA (7), i-propyl and cyclohexyl esters of VA (13 and17 respectively) and ethyl ester of GA (20) treatment significantly lowered the death rate and increased the recovery from paralysis due to the thrombotic challenge. From the limited analogs available, it was tentatively concluded that the structural conformation, where carboxy oxygen (=O or-O?) of the carboxyl group (COOH) at C1 and the oxygen function at C3 (either OH or OCH3) are closely situated, is favorable for the esters of PA, VA and GA to be more antithrombotic. 相似文献
87.
The Gastric Bypass for Failed Bariatric Surgical Procedures 总被引:1,自引:0,他引:1
Background: Revision of failed bariatric surgical procedures is a significant challenge for every bariatric surgeon. Methods:
Evaluated are surgical difficulties, management problems and weight loss in patients with distal gastric bypass as a revisionary
procedure. Eighty patients were followed up to 3 years; four were lost to follow-up. Mean age was 43; mean prebariatric surgery
weight 134 kg; height 1.65 meters; body mass index 40.1; ideal body weight 62.7 kg; excess weight 70.5 kg; per cent excess
weight 214%. A 250 cm stomach-to-ileocecal valve segment of small bowel was used, and the biopancreatic secretions were brought
into the terminal ileum 100 cm from the ileocecal valve. Mean pouch size was 63 cc; length of hospital stay 5 days; operative
blood loss 616 cc; operative time 130 min. Results: Intraoperative complications included three splenic injuries (without
splenectomy). Early complications included one deep vein thrombosis, two marginal ulcers, one GI hemorrhage, one wound dehiscence,
one pouch outlet obstruction and one pancreatitis. Late complications included: one death from protein malnutrition/ARDS;
21 hypoproteinemia; six protein malnutrition, and of these, three had hyperalimentation; three cholecystitis; 27 anemia; 22
incisional hernia; two staple-line disruption (reoperated); 26 low serum iron; 11 prolonged (> 6 months) diarrhea; three prolonged
frequent vomiting; and two unrelated deaths (chronic myelogenous leukemia and amyotrophic lateral sclerosis). Mean excess
weight loss was 83% at 12 months; 89% at 24 months; and 94% at 36 months. Conclusion: The distal gastric bypass is fraught
with the operative and immediate post-operative complications experienced in any revisionary bariatric surgery. Distal gastric
bypass is very effective in producing long-term weight loss. Nutritional problems are common but usually easily corrected.
The most serious nutritional complication is protein malnutrition, which must be identified and corrected early. Success of
this procedure is dependent upon patient compliance with proper nutrition and supplements, and regular office follow-up with
monitoring of laboratory data. Patients who are noncompliant are at significant risk for complications. 相似文献
88.
Dong M. Shin Alan M. Kramer Isaiah W. Dimery Martin N. Raber Michael Ewer Waun Ki Hong 《Investigational new drugs》1991,9(1):89-91
Summary Fourteen patients previously treated with surgery, radiotherapy, and/or chemotherapy for primary squamous cell carcinoma of the head and neck were treated with 4-O-tetrahydropyranyl-Adriamycin (THP-adriamycin) for locally or distantly recurrent disease. The starting dose was 60 mg/m2 by i.v. infusion, with courses repeated every 3 to 4 weeks. A total of 34 courses of treatment were delivered (median, 2; range, 1–6). All patients were evaluable for response and toxicity. There were no responses. Severe (grade 3 or 4) neutropenia occurred in 11 patients. Thrombocytopenia, anemia, and gastrointestinal toxicity were modest, and no hepatic, renal, or cardiac toxicity was observed. The lack of response in association with severe neutropenia and moderate other toxicities using this dose and schedule of THP-Adriamycin should be taken into consideration prior to the pursuit of further study of this compound in a similar patient population. 相似文献
89.
Histoclinical Analysis of Early Colorectal Cancer 总被引:5,自引:0,他引:5
To evaluate the clinicopathologic characteristics of early colorectal cancer (ECC), histopathologic and clinical features
of 90 ECC patients who underwent surgical resection (not including the endoscopic polypectomized cases) and 1704 patients
with advanced colorectal cancer were analyzed. Smaller size, better histologic differentiation, less lymph node (LN) metastasis,
and better clinical outcome were observed in those with ECC than in patients with more advanced lesions. LN metastasis was
found in 5 patients with ECC among the 56 patients who underwent bowel resection (8.9%). Tumors with LN metastasis were more
frequently associated with deep submucosal invasion, absence of an adenomatous component within the tumor, sessile configuration,
and lymphovascular invasion. Tumors showing deep submucosal layer invasion were associated with a more unfavorable histologic
grade, lymphovascular invasion, LN metastasis, sessile morphology, and absence of an adenomatous component within the tumor.
Recurrence was observed in two patients who underwent local excision for their submucosal cancer. One of the patients was
salvaged after bowel resection, but one patient died of distant metastasis. From our data analysis and literature review,
extensive submucosal invasion, lymphovascular invasion, sessile configuration, and tumors with no adenomatous component should
be considered high risk factors for LN metastasis and recurrence after limited therapy. 相似文献
90.
The effects of intracerebroventricular (i.c.v.) and intrathecal (i.t.) 3-isobutyl-1-methylxanthine (IBMX), cholera toxin (CTX) and pertussis toxin (PTX) administration on immobilization-induced antinociception were studied in ICR mice. Antinociception was assessed by the tail-flick assay. Immobilization of the mouse increased inhibition of the tail-flick response for at least 1 h. The pretreatment with i.t. IBMX (0.01-1 ng), but not i.c.v. IBMX, significantly attenuated immobilization-induced inhibition of the tail-flick response. The pretreatments with i.c.v. PTX (0.05-0.5 microg) as well as i.t. CTX, but neither i.c.v. CTX (0.05-0.5 microg) nor i.t. PTX, potentiated the inhibition of the tail-flick response induced by immobilization stress. Our results suggest that spinally located phosphodiesterase appears to be involved in the production of immobilization stress-induced antinociception. In addition, inactivation of supraspinally located PTX-sensitive G-proteins and spinally located CTX-sensitive G-proteins may modulate immobilization stress-induced antinociception. 相似文献