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111.
BACKGROUND: Closure of a large ventricular septal defect (VSD) in children with elevated pulmonary vascular resistance is associated with significant morbidity and mortality. Pulmonary hypertensive episodes continue to be a major cause of postoperative morbidity and mortality. We designed a fenestrated flap valve double VSD patch in an effort to decrease the morbidity and mortality associated with the closure of a large VSD with elevated pulmonary vascular resistance. METHODS: Eighteen children (mean age, 5.7 years) with a large VSD and elevated pulmonary vascular resistance (mean, 11.4 Wood units) underwent double patch VSD closure using moderately hypothermic cardiopulmonary bypass and cardioplegic arrest. The routine VSD patch was fenestrated (4 to 6 mm) and on the left ventricular side of the patch, a second, smaller patch was attached to the fenestration along its superior margin before closure of the VSD. RESULTS: All children survived operation and were weaned from inotropic and ventilator support within 48 hours postoperatively. Postoperative pulmonary artery pressures were significantly lower than preoperative values. One child died 9 months postoperatively. CONCLUSIONS: Closure of a large VSD in children with elevated pulmonary vascular resistance can be performed with low morbidity and mortality when a flap valve double VSD patch is used.  相似文献   
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Pediatric dual-energy X-ray absorptiometry spine scans often cannot be analyzed with standard software due to a failure to identify the bone edges of low density vertebrae. Low density spine (LDS) software improves bone detection compared with standard software. The objective of this study was to compare bone mineral density (BMD) measurements obtained with the standard and LDS software in 27 healthy nonobese, 32 obese, and 41 chronically ill children, ages 2-18 years. Lumbar spine (L1-L4) BMD, measured by standard analysis, ranged from 0.531-1.244 gm/cm2. Reanalysis with the LDS software resulted in a systematic increase (mean +/- SD) in estimated bone area of 17.0+/-5.0%, an increase in bone mineral content of 6.1+/-6.3%, and a mean decrease in BMD of 8.7+/-1.7% (all p < 0.001). This resulted in a mean decrease in BMD Z score of 0.7+/-0.2. Linear regression models, predicting standard BMD from LDS BMD, were fit for the three subject groups (R2 = 0.993-0.995). Small differences in slopes were detected across groups (p = 0.07); LDS BMD predicted higher standard BMD in obese subjects. In conclusion, LDS analysis resulted in a clinically significant decrease in measured BMD. The association between analysis methods was exceptionally high (R2 > 0.99), indicating that LDS BMD accurately predicts standard BMD. Although LDS BMD in obese subjects predicts higher standard BMD results than in nonobese subjects, the small difference is of questionable clinical significance. LDS software is a useful tool for the assessment of BMD in children.  相似文献   
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Microdialysis experiments performed in the dorsal hippocampus of freely moving rats showed that L-(E)-4-(3-phosphono-2-propenyl)piperazine-2-carboxylic acid (L-CPPene) is 10 times as potent as D-CPPene in inhibiting potassium-induced increases in extracellular levels of aspartate and glutamate. In control experiments, two 100 mM KCl stimuli (S1 and S2) applied for 10 min each (separated by a 40-min recovery period) produced substantial (300-500%) increases in the extracellular levels of aspartate, glutamate, taurine, and GABA and a 50% decrease in the glutamine level. S2/S1 ratios in the control groups were 0.67 (aspartate), 0.78 (glutamate), 0.83 (GABA), and 0.85 (taurine). In the experimental groups, D- or L-CPPene was applied via the probe during the second potassium stimulus (S2). L-CPPene (25 or 250 microM) produced selective suppression of potassium-induced increases of extracellular glutamate (S2/S1 ratio: 0.25) and aspartate (S2/S1 ratio: 0.20) levels, whereas 250 microM D-CPPene was required to inhibit the extracellular aspartate and glutamate increases. Neither enantiomer of CPPene affected the potassium-induced increases of GABA and taurine or the decrease in extracellular glutamine concentration. An additional study comparing the anticonvulsant potencies of D- and L-CPPene was performed using audiogenic DBA/2 mice. The anticonvulsant potency of D-CPPene, as assessed against sound-induced seizures in DBA/2 mice, was an order of magnitude higher than that of L-CPPene [ED50 clonic phase (intraperitoneal, 45 min): 1.64 mumol/kg and 16.8 mumol/kg, respectively]. We attribute the anticonvulsant action of D-CPPene to its antagonist action at the NMDA receptor.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A new, field-adapted, colorimetric method for detecting sulfonamide drugs in urine is described. The method uses the color reagent, p-dimethylaminocinnamaldehyde, and has a detection limit of about 1 microgram/ml. Analysis of 35 samples collected in the field, comparing results obtained with the colorimetric field test with those obtained using high-performance liquid chromatography, indicated a calculated sensitivity value of 94% and a specificity value of 94% for the test to detect the presence of sulfonamides. The field test can be modified to allow quantitation of sulfonamides in urine in field situations, using a hand-held, portable photometer for measuring the absorbance of test solutions. For this test, calculated coefficients of variation for day to day reproducibility were < or = 5% at sulfonamide concentrations > or = 3 micrograms/ml. This new test for detecting the presence of sulfonamides in urine is more sensitive and reliable than the presently used Bratton-Marshall test.  相似文献   
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The synthesis and biological activity of the novel series of 1 beta-methylcarbapenems, 1 and 2 were described. Most compounds displayed high potent antibacterial activity. The best compound in this series, 2a (IH201; R2 = NH2) showed an excellent and a broad spectrum as well as high renal DHP-I stability. It also possessed good in vivo efficacy and high safety.  相似文献   
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OBJECTIVE: To explore the feasibility of recruiting, training, and placing in the field volunteers to assist community practices in enhancing the provision of preventive care. DESIGN: A case series design followed up a cohort of volunteers prospectively as they were recruited, trained, and assigned to practices. SETTING: The New Hampshire Division of the American Cancer Society recruited and trained the volunteer facilitators. INTERVENTION: Assistance from the volunteers in implementing a preventive services office system served as the intervention for practices. Volunteers were trained and supported by professional staff and an implementation manual. MAIN OUTCOME MEASURES: Recruitment, training, and volunteer experiences in working with practices, as well as the costs of supporting the program, were assessed. RESULTS: Twenty-six volunteers were trained. Of the 15 assigned to practices, 11 had begun to assist their assigned practices to establish a preventive services office system. Extensive planning, patience, and support were required. CONCLUSION: Volunteers recruited and supported by an intermediary organization can provide assistance to practices in implementing a preventive services office system.  相似文献   
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PURPOSE: The aim of the present study was to investigate carcinoembryonic antigen (CEA), CA19.9, and CA72.4 in the serum and gastric juice of patients with gastric cancer. METHODS: Serum and gastric juice tumor markers CEA, CA19.9, and CA72.4 were measured in 59 patients who had gastric adenocarcinomas and were undergoing curative gastrectomy. The same markers were measured in 47 patients with benign gastric disorders and in 40 healthy subjects. The correlation between the serum and gastric juice levels of tumor markers and several clinicopathological factors were evaluated by univariate analysis. The significance of the tumor markers as prognostic factors was assessed both by univariate and multivariate analysis. RESULTS: The positivity rates of serum CEA, CA19.9, and CA72.4 were 57.6%, 38.9%, and 18.6% respectively. The positivity rates of gastric juice CEA, CA19.9, and CA72.4 were 62.7%, 30.5%, and 23.7% respectively. The combination of serum and gastric juice markers gave a positivity of 81.3%. There was no correlation between serum and gastric juice level of each tumor marker. Positivity of gastric juice markers did not correlate with prognosis. A significant difference in prognosis was observed between patients positive and negative for serum CEA and CA19.9. Multivariate analysis also revealed that serum CEA and CA19.9 levels were independent prognostic factors. CONCLUSIONS: Levels of both serum and gastric juice tumor markers continue to have only limited diagnostic usefulness in gastric cancer patients. CEA and CA19.9 in the preoperative sera are good prognostic factors, whereas the presence of tumor markers in the gastric juice does not play any prognostic role.  相似文献   
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