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971.
972.
973.
Introduction: Laparoscopic appendectomy (LA) can be performed safely and effectively using endoloops (EL) or endostaples (ES). We compared EL and ES for stump closure during LA for complicated appendicitis in children. Methods: All LA for complicated appendicitis performed between July 2005 and August 2009 were assessed prospectively. EL were used in 37 procedures and ES in 31. Apart from choice of technique which was the personal preference of the attending surgeon, all patients were managed according to the same intraoperative and postoperative protocols. Results: There was no significant difference between mean age at operation; gender ratio; mean preoperative and postoperative white blood cell; mean preoperative and postoperative white blood cell C‐reactive protein; histopathology; mean operating time (EL: 71 minutes; ES: 64 minutes); mean hospitalization (EL: 5.3 days; ES: 5.1 days); febrile period (EL: 2.1 days; ES: 1.9 days); white blood cell normalization (EL: 2.6 days; ES: 2.4 days); and intravenous antibiotic usage (EL: 3.8 days; ES: 3.7 days). There were no intraoperative complications or ICU admissions in either group, but two EL cases required conversion to open surgery (P=NS). Incidences of intra‐abdominal abscess (EL: n=1 or 2.7%; ES: n=1 or 3.2%), transient ileus (EL: n=2 or 5.4%; ES: n=2 or 6.4%), small bowel obstruction (EL: n=0; ES: n=0), and wound infection (EL: n=1 or 2.7%; ES: n=1 or 3.2 %) were not significantly different. Rate of rehospitalization for EL was 2.7% (n=1; colitis), and for ES, it was 3.2% (n=1; intra‐abdominal abscess) (P=NS). Mean cost for EL was US$890, and for ES, it was US$1300. Conclusion: This is the first prospective study comparing EL and ES during LA for complicated appendicitis in children. ES is more expensive, but there was no significant difference in morbidity for this technique, particularly with regard to incidence of postoperative intra‐abdominal abscess.  相似文献   
974.
Type IV collagen is a major component of the glomerular and tubular basement membrane. We used a specific radioimmunoassay to determine (mean +/- SD) the concentration of carboxy terminal non-collagenous fragment (NC1) of type IV procollagen in the serum (normal 6.0 +/- 1.2 ng ml-1) and urine (normal 1.5 +/- 2.0 ng ml-1) of 142 patients with various kidney diseases. The 15 patients with active glomerulonephritis displayed (ANOVA, Scheffé test) significantly elevated NCl values in their serum (14 +/- 8.2 ng ml-1) as compared with the 32 patients with chronic interstitial nephritis (7.8 +/- 3.0 ng ml-1), the 17 patients with various other chronic kidney diseases (8.1 +/- 2.4 ng ml-1) and the 23 ambulatory kidney transplant patients (9.1 +/- 1.7 ng ml-1). The highest serum NCl concentrations were found in nine patients with membranoproliferative glomerulonephritis (16 +/- 9.4 ng ml-1). Sequential serum NCl concentrations in the one patient with active Goodpasture's syndrome were marginally elevated (less than 11 ng ml-1). Serum NCl did not increase with acute interstitial rejection episodes in six kidney transplant patients. The highest urinary NCl concentrations were found in seven patients with minimal change glomerulonephritis (7.5 +/- 3.2 ng ml-1). No correlation was found between serum NCl and serum creatinine, NCl and creatinine clearance, or renal NCl clearance and creatinine clearance. There was a significant correlation between serum NCl and proteinuria. Serum and urinary NCl concentrations were elevated independently from renal function, thus indicating intrinsic renal disease.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
975.
Cytochrome P450(CYP) comprises a large superfamily of hemoproteins that plays a vital role in the biotransformation of variety of xenobiotics as well as endobiotics. CYPs 1-4 metabolize foreign compounds such as drugs, environmental pollutants and carcinogens influencing drug-drug interactions, drug or carcinogen activation and detoxification, and in addition, xenobiotics induce CYP genes. CYPs 1-4 also metabolize endogenous compounds, including steroid hormones, retinoid, bile acids, prostagrandins, and thus have roles in not only elimination but also production of endobiotic signaling molecules. Some of the orphan receptors may function as the receptors of these signaling molecules.  相似文献   
976.
Hitherto, seminal plasma maltase has been measured with maltose as substrate; this method is time consuming and lacks specificity. The use of a synthetic substrate, p-nitrophenol-alpha-D-glucopyranoside, allows accurate and rapid determination of this activity. When maltase is added to the incubation medium (the substrate and reduced glutathione in potassium phosphate buffer, pH 6.8), maintained at 37 degrees C, hydrolysis of the original substrate to p-nitrophenol goes at a constant rate during 4 h. Under optimal conditions of incubation, the Michaelis constant of the reaction, calculated by the Hanes method, was 2.92 +/- 0.84 (SD) X 10(-3) for six different semen samples. Isomaltase appeared to be absent from seminal plasma. The enzyme is stable to freezing and slow thawing and can be stored for at least 26 days at -80 degrees C. Its molecular weight is 259 000. Tris(hydroxymethyl)aminomethane (pH 6.8) exerts a noncompetitive inhibition on the enzyme activity. In 68 men 23 to 45 years old, whose semen analyses were normal, the seminal plasma maltase activity was 467 +/- 135 (SD) mU/g of protein. It was generally decreased in patients with infertility disorders.  相似文献   
977.
978.
Transglutaminase (TGase)-induced activation of small G proteins via 5-hydroxytryptamine (HT)(2A) receptor signaling leads to platelet aggregation (Cell 115:851-862, 2003). We hypothesize that stimulation of 5-HT(2A) receptors in neurons activates TGase, resulting in transamidation of serotonin to a small G protein, Rac1, thereby constitutively activating Rac1. Using immunoprecipitation and immunoblotting, we show that, in rat cortical cell line A1A1v, serotonin increases TGase-catalyzed transamidation of Rac1. This transamidation occurs in both undifferentiated and differentiated cells. Treatment with a 5-HT(2A/2C) receptor agonist 2,5-dimethoxy-4-iodoamphetamine, but not the 5-HT(1A) receptor agonist 5-hydroxy-2-dipropylamino tetralin, increases transamidation of Rac1 by TGase. In A1A1v cells, 5-HT(2A) receptors mediate the transamidation reaction because expression of 5-HT(2C) receptors was not detectable and the selective 5-HT(2A) receptor antagonist blocked transamidation. Time course studies demonstrate that transamidation of Rac1 is significantly elevated after 5 and 15 min of serotonin treatment, but returns it to control levels after 30 min. The activity of Rac1 is also transiently increased following serotonin stimulation. Inhibition of TGase by cystamine or small interfering RNA reduces TGase modification of Rac1, and cystamine also prevents Rac1 activation. Serotonin itself is bound to Rac1 by TGase following 5-HT(2A) receptor stimulation as demonstrated by coimmunoprecipitation experiments and a dose-dependent decrease of serotonin-associated Rac1 by cystamine. These data support the hypothesis that Rac1 activity is transiently increased due to TGase-catalyzed transamidation of serotonin to Rac1 via stimulation of 5-HT(2A) receptors. Activation of Rac1 via TGase is a novel effector and second messenger of the 5-HT(2A) receptor-signaling cascade in neurons.  相似文献   
979.
BACKGROUND AND STUDY AIMS: As endoscopic techniques continue to develop, endoscopic mucosal resection is increasingly being used in the treatment of intramucosal gastric tumors. The aim of this study was to explore the feasibility of piecemeal endoscopic aspiration mucosectomy for large superficial intramucosal tumors of the stomach. PATIENTS AND METHODS: The study group consisted of five consecutive patients with large superficial intramucosal tumors of the stomach, 4 cm or more in diameter. Piecemeal endoscopic aspiration mucosectomy using a cap-fitted panendoscope was carried out. The initial resection was undertaken at the oral side of the lesion. Subsequent resections were carried out along the anal margin of the previous resection site, until the marks around the boundary of the tumor completely disappeared. RESULTS: The shape of the tumors was slightly elevated in four cases and slightly depressed in one. The mean diameter of the tumors was 4.8 cm. The diameters of the resected specimens ranged from approximately 1.0 cm to 2.3 cm. The numbers of piecemeal resection procedures needed per lesion ranged from five to 18 (mean 11). The visual field was well ensured by the cap, and the tumors were macroscopically completely resected without any complications in all patients. The final histological diagnoses in the specimens were adenoma in one case and mucosal carcinoma in adenoma in four. One patient had residual or recurrent tumor, and received full treatment with additional endoscopic procedures. CONCLUSIONS: Piecemeal endoscopic aspiration mucosectomy is a simple and very useful technique for treating large superficial intramucosal tumors of the stomach.  相似文献   
980.
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