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683.
Walker Don W.; Messer Linda G.; Freund Gerhard; Means Larry W. 《Canadian Metallurgical Quarterly》1972,80(3):469
Trained 7 unoperated male Long-Evans hooded rats and 14 Ss with bilateral hippocampal or cortical lesions made by aspiration on a go, no-go task in which bar presses were reinforced on alternate trials. Performance was evaluated with both latency ratios (latency to 1st response on go trials/latency to 1st response on no-go trials) and response ratios (total responses on no-go trials/total responses on go trials). Ss were trained to criterion at successively increasing durations of ITI (10, 20, 40, and 80 sec.). While Ss with hippocampal lesions acquired the task more rapidly than controls with the initial 10-sec ITI, they were severely impaired when tested with the longer ITIs. (23 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
684.
A Szold O Zamir D Eimerl D Keret I Deutsch HR Freund 《Canadian Metallurgical Quarterly》1995,128(9):537-9, 599
We present our initial experience with laparoscopic colonic resection in 15 patients: adenocarcinoma of the colon, 10 cases, giant villous adenoma (2), arteriovenous malformation (2), and a case of benign stricture. Mean operating time was 190 minutes and there were no intraoperative complications. The margins of resection and number of resected lymph nodes in patients with malignancy were comparable to those in the conventionally operated. Mean postoperative hospital stay was 6.1 days. During a maximum follow-up of 15 months there were no wound or trocar-site recurrences. We conclude that laparoscopic colonic resection is technically feasible and safe. However, its use for treating malignant diseases of the colon needs further study. 相似文献
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Thomas A. Zevaco Jakub Sypien Annette Janssen Olaf Walter Eckhard Dinjus 《Catalysis Today》2006,115(1-4):151-161
Reacting triethyl aluminum and diethyl aluminum chloride with the chelating bisphenol ligands mdtbpH2 and mmcpH2 [mmcpH2: 2,2′-methylenebis(4-methyl-6-(1-methyl-cyclohexyl)phenol); mdtbpH2: 2,2′-methylenebis(4,6-di-tert-butyl-phenol)] afforded monomeric and dimeric aluminum bisphenoxides with reactive Al–Cl and Al–C2H5 moieties. We present here the X-ray structure determination of some of the isolated compounds as well as the preliminary catalytic tests in copolymerization reactions with cyclohexene oxide and carbon dioxide. 相似文献
688.
Trichothecene mycotoxins in animal feed and human food can cause fatalities in livestock and disease in humans. In addition, these toxins are suspected chemical warfare agents. Therefore, development of a simple and sensitive method for the screening of trichothecenes is important to prevent economic loss and health hazards. A simple and inexpensive method for the detection of type-B trichothecene mycotoxins has been developed in our laboratory. By hydrolyzing the toxin under basic conditions at 80 degrees C for 1 h it is possible to detect the toxin with simple electrochemical techniques. Deoxynivalenol (DON), commonly known as vomitoxin, was used as a representative compound for type-B trichothecenes in this detection scheme. The detection limit for DON using our procedures was determined to be 9.1 microM in solution, corresponding to 0.24 ppm in a 25-g grain sample if the final extraction volume is 2.2 mL. The linear dynamic detection range was determined to be from 0.32 ppm to greater than 32 ppm. In addition to standard solutions, this method was used on rice samples spiked with DON. It was demonstrated that there is no electrochemical interference from rice extract and that 1 ppm of DON in rice samples can be quantified. This method may be ideal for toxin screening in animal feeds or in runoff from sites that produce the compounds as chemical warfare agents. Since the active moiety in DON is common to virtually all type-B trichothecenes, our approach may be ideal for type-specific screening. 相似文献
689.
Morgan R.A. Guth G.D. Zimmer C. Leibenguth R.E. Focht M.W. Freund J.M. Glogovky K.G. Mullally T. Judd F.F. Asom M.T. 《Photonics Technology Letters, IEEE》1994,6(8):913-917
We present the design, fabrication, and demonstration of a 10×10 matrix-addressed vertical-cavity top-surface-emitting laser (VCSEL) array. These arrays are batch-fabricated from full 3-in diameter GaAs/AlGaAs wafers. We show that no performance-penalty is paid using top-contacted matrix addressed pixels over conventional planar VCSEL devices. A computer-controlled display system for electrically addressing the array was designed and constructed to permit video demonstration and array testing 相似文献
690.
N Lingens M Freund T Seeman K Witte B Lemmer K Sch?rer 《Canadian Metallurgical Quarterly》1997,86(7):719-723
Ambulatory blood pressure monitoring over 24 h was applied in 31 children with kidney disease, aged 3-19 (median 11) years, in the absence of renal insufficiency and without antihypertensive therapy. Median creatinine clearance was 112 ml/min/1.73m2. Ambulatory blood pressure monitoring revealed that eight patients (26%) were hypertensive during the daytime, compared to 62% through casual recordings obtained in the office and 38% when blood pressure was taken at home. Nocturnal hypertension was detected by ambulatory monitoring in six patients, two of whom had normal blood pressure in the daytime. Median nocturnal dipping was 13% for systolic and 21% for diastolic blood pressure, i.e. similar to healthy children. Rhythm analysis recognized a distorted circadian pattern for systolic and/or diastolic blood pressure in eight patients. In conclusion, ambulatory blood pressure monitoring allows the evaluation of hypertension more reliably than casual recordings in the office. Nocturnal hypertension, as a major risk factor for renal deterioration, is detected in a similar proportion as daytime hypertension in almost 20% of untreated children with kidney disease and normal renal function. 相似文献