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J Dow M A Petty J M Grisar E R Wagner K D Haegele 《Drug metabolism and disposition》1991,19(6):1040-1045
MDL74270 (6-acetyloxy-3,4-dihydro-N,N,N,2,5,7, 8-heptamethyl-2H-1-benzopyran-2-ethanaminium, 4-methylbenzenesulfonate) is a quaternary amine analogue of alpha-tocopherol with free radical scavenger properties. Rats were injected iv with [14C]MDL74270 (0.91 mg/kg), and whole blood and heart tissue were sampled. Five min after drug, the heart tissue/blood ratio (T/B) of radioactivity was 3.5, whereas at 1 hr it was 20.1 and remained at this value up to at least 6 hr. After iv administration the t 1/2 of radioactivity in blood was 6.3 hr, but po blood levels could not be quantified. The 0- to 96-hr urinary elimination of radioactivity was 39.9 +/- 5.7% of the dose after iv and only 1.2 +/- 0.4% after po administration, conversely, 44.7 +/- 5.2% was excreted in feces after iv and 79.1 +/- 17.4% after po administration. These results confirmed poor oral absorption of the compound. Tissue distribution of [14C]MDL74270 was compared with that of its tertiary amine analogue [14C]MDL74366 in rat heart, skeletal muscle, brain, and whole blood, after iv administration (1 mg/kg). The heart T/B was above 20, 1-6 hr after [14C]MDL74270, whereas it was less than 2 after [14C]MDL74366. Over the 1- to 6-hr time interval, skeletal muscle T/B varied from 1.8 to 5 compared with 1.5 to 0.6 for [14C] MDL74366. Brain T/B was higher after the tertiary amine compound. Results showed marked cardioselectivity of radioactivity after [14C] MDL74270. Differential centrifugation of heart homogenates showed that radioactivity was equally distributed between the major subcellular fractions studied.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Laparoscopic-assisted percutaneous endoscopic gastrostomy in children and adolescents. 总被引:3,自引:0,他引:3
Sherman C Yu John K Petty Denis D Bensard David A Partrick Jennifer L Bruny Richard J Hendrickson 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(3):302-304
OBJECTIVE: Pediatric gastric access for long-term enteral feeding may be performed via a laparotomy, laparoscopy, or a percutaneous approach. In children and adolescents, laparoscopic-assisted gastrostomy may be difficult due to a thick abdominal wall. Therefore, if the abdominal wall is estimated to be >2 cm on physical examination, or in children in whom a percutaneous endoscopic gastrostomy was unsuccessfully attempted by a gastroenterologist, we routinely perform a laparoscopic-assisted percutaneous endoscopic gastrostomy. METHODS: From January 1998 through February 2003, we retrospectively reviewed 15 cases of a laparoscopic-assisted percutaneous endoscopic gastrostomy. Instruments used to perform this technique are a percutaneous endoscopic gastrostomy kit, an Olympus flexible endoscope, and one 5-mm STEP port placed through an infraumbilical incision for a 5-mm, 30-degree scope. RESULTS: Age range was 2 years to 20 years (mean, 10). Operative time ranged from 20 minutes to 45 minutes. When a concurrent laparoscopic Nissen fundoplication was performed (n = 6), the percutaneous endoscopic gastrostomy was placed after completion of the Nissen fundoplication. No intraoperative complications occurred, and all tubes were successfully placed. Feeds were instituted the following day and advanced to goal. To date, no postoperative complications have occurred, and revision has not been necessary. CONCLUSIONS: Laparoscopic-assisted percutaneous endoscopic gastrostomy in children and adolescents is safe and effective. Utilizing laparoscopy permits evaluation of the peritoneum and lysis of adhesions, if necessary. Moreover, laparoscopy provides excellent exposure for accurate placement of the PEG, while avoiding injury to other organs. 相似文献
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AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice. 相似文献