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71.
Purpose Nausea/vomiting are significant side effects associated with the use of chemotherapy in cancer patients. Treatment of nausea/vomiting caused by cisplatin, a potent chemotherapeutic agent and one of the most emetogenic stimuli, requires a combination of different antiemetic drugs. In this study, we investigated the effects of Scutellaria baicalensis, an antioxidant herbal medicine, on cisplatin-induced nausea using a rat model.Methods Rats react to emetic/nausea-producing stimuli, such as cisplatin, with altered feeding habits, manifested by pica or increased consumption of kaolin (a type of clay). We measured pica in rats to quantify cisplatin-induced nausea, and to evaluate the antinausea effect of pretreatment with S. baicalensis extract (SbE) given intraperitoneally.Results Cisplatin at 3 mg/kg induced significant pica accompanied by reduced food intake, suggesting the presence of nausea. Hence, this cisplatin dose was selected for testing the antinausea activity of SbE. Cisplatin-induced pica decreased significantly when animals were pretreated with SbE at doses of 1 mg/kg and 3 mg/kg (P<0.01). At a higher SbE dose (10 mg/kg), kaolin consumption increased, rather than further decreased, and was significantly different from that in the groups treated with low SbE doses.Conclusions SbE pretreatment decreased cisplatin-induced kaolin intake in the rat model of simulated nausea, suggesting that SbE and its active constituent(s) may play a therapeutic role in chemotherapy-induced emesis. Absence of therapeutic effect at the highest tested SbE dose could have been a result of prooxidant activity often associated with excess antioxidant concentration.This work was supported in part by NIH grants R01 CA79042, P30 CA14599, and R21 AT00381.  相似文献   
72.
S-(1,2-dichlorovinyl)-L-cysteine (DCVC), a metabolite of a common environmental contaminant, trichloroethylene, is a selective proximal tubular nephrotoxicant. The objective of our study was to examine the dose-response relationship of renal injury and repair following DCVC administration. Male Swiss-Webster mice were injected with DCVC [15, 30, or 75 mg/kg ip in distilled water (10 ml/kg)] and the extent of nephrotoxicity and tissue repair was assessed over a 14-day period. The renal injury due to the low and medium doses of DCVC peaked at 36 and 72 h after dosing, respectively, and then regressed over time due to a timely and adequate tissue repair response. At the highest dose tissue repair was inhibited, thereby causing progression of renal injury, which led to acute renal failure and death of the mice. The possibility that compromised tissue repair was a result of the extensive nephrotoxic injury attendant to the high dose of DCVC was investigated via an equinephrotoxicity study in which separate groups of mice received 40 (LD40) and 75 (LD90) mg DCVC/kg, respectively. Bioactivation-based renal proximal tubular injury measured in these two groups over a time course was identical but there was a marked difference in mortality due to an early and robust tissue repair in the first group relative to the second group. These results support the concept that quantitative evaluation of renal tissue repair in parallel with injury is useful in the assessment of the likely toxic outcome associated with exposure to nephrotoxic drugs and toxicants.  相似文献   
73.
Sigmoid colectomy-open or laparoscopic-has been advocated as the treatment of sigmoid volvulus. This has a higher incidence of morbidity and mortality. We have successfully treated 2 cases of recurrent sigmoid colon volvulus with laparoscopic sigmoidopexy by extraperitonealization of the sigmoid colon. Laparoscopic sigmoidopexy by this technique has not been reported before. The first patient was a 20-year-old male and the second was a 72-year-old female. In both patients, initial detorsion of volvulus was achieved by rectal tube. As the colon was nongangrenous, elective laparoscopic sigmoidopexy by extraperitonealization of the sigmoid colon was performed 4 days after the detortion. Operative times were 50 minutes and 70 minutes. Both patients were discharged from the hospital on the third postoperative day. There has been no recurrence of volvulus over a period of 6 and 7 months. There were no complications. In conclusion, laparoscopic sigmoidopexy by extraperitonealization of the sigmoid colon may become a superior alternative for the treatment of sigmoid volvulus with nongangrenous colon.  相似文献   
74.
75.
杜晓川  贾红梅  莫显斌 《医学争鸣》1999,20(9):S046-S046
1 病例报告 男,7岁.因双下肢不等长,右膝及右踝关节骨性肿大就诊.无明显外伤史,亦无红、肿、热、痛病史.查体:发育正常,营养良好.双下肢不等长,左60cm,右64cm,有跛行.右膝及右踝内侧肿大,肤色正常,关节活动无异常.X线:右侧半身诸关节(肩、肘、腕、髋、膝、踝)骨骺及干骺发育均较左侧增大,肢体较长,骨骺出现亦较对侧提早.如右尺骨茎突骨骺较左侧提早出现(图1).右肘关节肱骨小头骨骺较左侧增大(图2).右髋臼发育浅平,边缘毛糙,右股骨头骨骺较左侧明显增大,其距泪滴之距离较左侧大1.0cm,呈…  相似文献   
76.
77.
本文设计合成了丁公藤碱Ⅱ的C_2脱氧和C_8电子等排类似物。药理结果表明,丁公藤碱Ⅱ的C_2羟基是保持其缩瞳活性的关键部分之一;目的物2和4各自分别具有拟和抗胆碱活性;电子等排目的物16和17既无拟也无抗胆碱作用。  相似文献   
78.
Experiments were conducted to affirm hepatic cytochrome P-450 involvement in the biotransformation of the class III antiarrhythmic agent, amiodarone (Am; Cordarone X) to its major metabolite, desethylamiodarone (DEA). Male Sprague-Dawley rats and male New Zealand white rabbits were treated with phenobarbital (PB) or 3-methylcholanthrene (3-MC) (to induce cytochrome P-450 (PB-inducible cytochrome(s) P-450) or P-448 (MC-inducible cytochrome P-450). In vivo decreases in rat hepatic microsomal cytochrome P-450 were achieved either by a single ip dose of CCl4 or by a 2-day treatment with CoCl2. In vitro biotransformation of Am by hepatic microsomes from PB-induced and 3-MC-induced rats and PB-induced rabbits was significantly greater than that from noninduced animals. Conversely, in vitro DEA production was significantly decreased with hepatic microsomes from CCl4- and CoCl2-pretreated rats. The classic P-450 inhibitors, piperonyl butoxide, SKF 525A, n-octylamine, and CO provided a significant reduction in the in vitro formation of DEA by microsomes from induced animals. In vitro DEA formation by hepatic microsomes from PB- and 3-MC-induced rats was significantly decreased by 0.5 mM chloroquine (specific inhibitors of PB-inducible cytochrome(s) P-450) and 0.3 mM quinacrine (specific inhibitor of MC-inducible cytochrome(s) P-450), respectively. Further evidence for involvement of gut microsomal flavin-containing monooxygenase was provided by the inhibition of gut microsomal-mediated in vitro DEA formation in the presence of methimazole. Methimazole had no effect on hepatic microsomal DEA production in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
79.
Male Sprague-Dawley rats (200-250 g) were maintained on a normal powdered diet or on a similar diet containing 10 ppm chlordecone (CD), 10 ppm mirex (M) or 225 ppm phenobarbital (PB) for 15 days. On day 15, the animals received a single i.p. administration of CCl4 (100 microliters/kg). Hepatic DNA, RNA, protein, lipid and glycogen were determined 1, 4, 6, 12, 24 and 36 h after CCl4 administration. A significant decrease (18%) in hepatic protein was observed 24 h after CCl4 challenge in the CD-pretreated rats; significant changes were not observed in the other treatment groups. Hepatic RNA was decreased (37%) in CD-pretreated rats at 36 h; no changes were observed in the DNA content. Hepatic RNA and DNA were increased (20% and 16%, respectively) 6 h after exposure to CCl4 alone. Lipid content was increased at all time points starting at 4 h in response to CCl4 challenge in the CD-pretreated rats. In the M- and PB-pretreated rats increases in hepatic lipid (22 and 28%, respectively) were observed only at the 6-h time point. Only a transient increase occurred after CCl4 alone at 4 h. While depletion of hepatic glycogen was manifested in all groups at all time points following CCl4, that in the CD + CCl4 group was the greatest. A recovery of glycogen beginning at 12 h was observed in the rats receiving CCl4 alone and in the M and PB pretreated animals. No such recovery was evident in CD + CCl4 group. These studies indicate that biochemical changes compatible with cellular death are more pronounced in the CD-pretreated rats than in those receiving CCl4 alone, suggesting that the metabolic and supportive biochemical mechanisms for hepatocellular repair are suppressed in rats receiving CD + CCl4.  相似文献   
80.

Background  

This study aims to contribute to the knowledge of the influence of comorbidity in OA. The objectives of the study were (i) to describe the prevalence of comorbidity and (ii) to describe the relationship between comorbidity (morbidity count, severity and the presence of specific diseases) and limitations in activities and pain in elderly patients with knee or hip OA using a comprehensive inventory of comorbidity.  相似文献   
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