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101.
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103.
T Piironen BO Villoutreix C Becker K Hollingsworth M Vihinen D Bridon X Qiu J Rapp B Dowell T L?vgren K Pettersson H Lilja 《Canadian Metallurgical Quarterly》1998,7(2):259-269
In comparison with pyeloplasty, endourologic procedures for the treatment of ureteropelvic junction obstruction offer good success rates with less morbidity and a shorter hospitalization; however, studies have found lower success rates and increased complications in patients with crossing vessels. Conventional diagnostic angiography and intravenous urography have both been used to identify crossing vessels at the UPJ; but, a reliable, less invasive, less costly, and simpler preoperative procedure to identify crossing vessels is needed. Helical CT with CT angiography is a promising noninvasive technique for the identification of crossing vessels at the ureteropelvic junction, which can be used for surgical planning of endourologic treatment of UPJ obstruction. 相似文献
104.
S Strand WJ Hofmann A Grambihler H Hug M Volkmann G Otto H Wesch SM Mariani V Hack W Stremmel PH Krammer PR Galle 《Canadian Metallurgical Quarterly》1998,4(5):588-593
We gave auditory examples of two semantic categories through headphones to 100 surgical patients anaesthetized with propofol and enflurane. This presentation was made during certain stages of the procedure, potentially associated with arousal, and during steady-state anaesthesia. Postoperative review using category generation tests showed successful priming in a pre-induction group but no evidence of implicit memory in the anaesthetized groups. These results suggest that timing an auditory input to coincide with surgical stimulation does not increase the probability of retrieval of information by this type of testing. 相似文献
105.
KN Furuya PR Durie EA Roberts SJ Soldin Z Verjee L Yung-Jato E Giesbrecht L Ellis 《Canadian Metallurgical Quarterly》1995,28(5):531-540
N-Acetyl aspartate (NAA) is the second most abundant amino acid in the human brain. NAA is synthesized by L-aspartate N-acetyl transferase or by cleavage from N-acetyl aspartyl glutamate by N-acylated alpha-linked L-amino dipeptidase (NAALADase); and it is catabolized to acetate and aspartate by N-acetyl aspartate amino hydrolase (amino acylase II). NAA is localized primarily to neurons, where it is concentrated in the cytosol. Although NAA is devoid of neurophysiological effects, it serves as an acetyl donor, an initiator of protein synthesis or a carbon transfer source across the mitochondrial membrane. The concentration of NAA in human brain increases 3-fold between midgestation and adulthood. In Canavan's Disease, an autosomal recessive disorder due to a null mutation in amino acylase II, NAA levels in brain are markedly increased and disrupt myelination. NAA levels have been found to be reduced in neurodegenerative disorders, including Alzheimer's Disease and Huntington's Disease. Since endogenous NAA can be readily detected in human brain by magnetic resonance spectroscopy, it is increasingly being exploited as a marker for functional and structural integrity of neurons in an expanding number of disorders. 相似文献
106.
107.
This paper is an extension of, and complementary to, an earlier paper by Wheatley, Vilches, and Abel. Some important fundamental questions which lead to degradation in the performance of a dilution refrigerator are considered: namely, convection on the dilute side and superfluid on the concentrated side. Experimental results are presented for a film suppressing still used in conjunction with a continuous-heat exchanger (several designs are considered) and a variable number (0–6) of step-heat exchangers of a copper-foil type with a high surface-area-to-viscous-impedance ratio. The first quantitative measurements of viscous heating on the dilute side are presented as well as measurements of thermal resistance on the dilute and concentrated side. Finally, the properties of the refrigerator under external heat load are considered.Supported by the U.S. Atomic Energy Commission under Contract AT(04-3)-34, P.A. 143. 相似文献
108.
A case of right atrial myxoma is described. The patient had vague and variable symptoms and it was not until five years after first presentation that she had developed clinical and electrocardiographic evidence of right atrial hypertrophy, and angiocardiographic evidence of a fist-sized myxoma which was subsequently removed surgically. 相似文献
109.
The sera of 30 healthy male beagles were analyzed by reversed-phase high-performance liquid chromatography. The profiles were compared with those obtained from the sera of 30 healthy human donors. The chromatograms of each group were very reproducible; however, there were characteristic differences between the two groups. The compounds observed in both the human and canine profiles were identified as creatinine, uric acid, tyrosine, hypoxanthine, xanthine, kynurenine, inosine and tryptophan. Compounds present only in the canine profiles were identified as cytindine, riboflavin and 5-methyl-cytidine. Compounds present only in the human profiles include uridine, guanosine, hippuric acid and the dietary dependent compounds theobromine and caffeine. The compounds present in both human and canine sera were quantitated and compared statistically. The amounts of these compounds were very similar, except for uric acid. 相似文献
110.
Departments of public health and agriculture in all 50 states of the United States and the District of Columbia were queried in 1977 to determine which of some selected zoonoses are reportable, the method of reporting and the diagnostic stage at which reporting is required. Fifty-three of the 62 diseases on the public health questionnaire were listed as reportable, with hepatitis A required by 49 of the 51 jurisdictions. Telephone reporting was required in nearly 19% of the disease-jurisdiction combinations and, in nearly 55%, reporting was required when the disease first was suspected. Thirty-three of the 41 diseases on the agriculture questionnaire were reportable, with anthrax most frequent. Telephone reporting was required in 30% of the reportable situations and suspected diagnoses were reportable in 54%. The disease lists varied markedly between the public health and agriculture agencies. 相似文献