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951.
If one listens to a meaningless syllable that is repeated over and over, he will hear it undergo a variety of changes that can be described systematically in terms of reorganization of the phones constituting the syllable and changes in a restricted set of phonetic distinctive features. When the repeated syllable is followed by a different syllable but in the same voice, the new (test) syllable will be misperceived in a manner related to the perceptual misrepresentation of the repeated syllable. In the present experiment subjects (N = 24) listened to 72 different experimental sequences of repeated syllables in a male voice followed by test syllables in a female voice. Identification of penultimate and test syllables was independent and in no instance were the phone constituting the syllables reorganized. These results are interpreted as evidence against both auditory and phonetic feature detector theories of speech perception. 相似文献
952.
The results of a two-year study on durability and cause of failure of electromyographic monopolar electrodes are reported. The electrodes were obtained from the regular stock of three different manufacturing sources. Durability is defined on the basis of the number of patients that could be examined before failure. The range was 3 to 110 with the averages 19.7, 33.8, and 62.5 for the three different manufacturers. Common causes of electrode failure included: Teflon retraction, 40.6%; tip dullness or burrs, 34.8%; structural failure of wire or pin, 13.1%; electrical artifacts, 9.7%; and bending of needle shank, 5.7%. Variations in manufactures' tip contour and bevel correlated with tip durability. 相似文献
953.
LM Silver 《Canadian Metallurgical Quarterly》1993,9(7):250-254
Mouse t haplotypes are descendents of a variant form of chromosome 17 that evolved the ability to propagate itself at the expense of the wild-type homolog from heterozygous +/t males. Although once enigmatic, these widespread selfish chromosomes have revealed many of their secrets in response to a combined assault with molecular, genetic and phylogenetic techniques. This review summarizes the current understanding of t haplotypes and their raison d'être. 相似文献
954.
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956.
J. P. Das et al (see record 1975-08765-001) claim that A. R. Luria's (1966) distinction between simultaneous and successive modes of information processing provides a more fruitful way of classifying cognitive processes than (a) the hierarchical models of C. Burt (see record 1973-10531-001) and P. E. Vernon (see record 1963-03855-001), A. R. Jensen's (see record 1969-09740-001) Levels 1 and 2, or A. Paivio's (see record 1976-01839-001) dual coding system of imagery and verbal mediation. Their published factor analyses are surveyed, and shown to yield only partial support for their views. A broader battery of 14 tests was given to 91 university students, and responses were factor analyzed. Two of the obtained factors involved various kinds of rote memorizing, and thus could be regarded as successive processing. Four other factors did not yield a general simultaneous factor, but classified the tests under Number-Spatial, Verbal-Spatial, Perceptual Reasoning, and a specific Digit Memory factor. Overall, the 6 factors tend to follow a multiple-factor, or a hierarchical model, rather than a dichotomous classification. (French summary) (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
957.
M Worthington LM Irvine D Crook B Lees RW Shaw JC Stevenson 《Canadian Metallurgical Quarterly》1993,59(3):522-526
OBJECTIVE: To study some of the metabolic effects of oral gestrinone on plasma lipoprotein risk markers for cardiovascular disease and on bone density, a risk marker for osteoporosis. DESIGN: Randomized double-blind study. SETTING: All patients were referred to Gynaecology Clinic of Royal Free Hospital Medical School. PATIENTS: Twenty premenopausal women with laparoscopically confirmed endometriosis. INTERVENTIONS: Subjects were randomized in a double-blind fashion to receive either 1.25 mg or 2.5 mg gestrinone two times per week for 6 months. MAIN OUTCOME MEASURE: Laparoscopy was performed before treatment, and clinical responses were determined by second laparoscopy after 6 months. Plasma lipid and bone density measurements during and after therapy were compared with baseline. RESULT: Median total endometriosis scores decreased from 7.5 to 1.0 in the 1.25-mg group and from 7.0 to 0 in the 2.5-mg group. There were no significant between-group differences in endometriosis scores. At both doses, bone density in the spine and the proximal femur was conserved, but plasma concentrations of low-density lipoproteins rose by 13% and those of high-density lipoproteins fell by 40%. CONCLUSIONS: Reducing the dose of gestrinone to 1.25 mg appeared to maintain the therapeutic effectiveness of this treatment but was still associated with potentially unfavorable effects on lipids and lipoproteins. 相似文献
958.
H-C. zur Loye R. Kershaw K. Dwight J.K. Pabst R.J. Lang A. Wold 《Materials Research Bulletin》1984,19(4):459-463
Gasification experiments were performed on Spherocarb samples containing 5 weight % calcium oxide at a gasification temperature of 760°C. The atmosphere was hydrogen/water mixture maintained at a mole ratio of 1:1. There is a correlation between the rate of gasification of Spherocarb and the degree of crystallinity of the calcium oxide residue. Segregation of the calcium oxide results in considerable loss of catalytic activity. 相似文献
959.
LM Ramonas LC Erickson H Ringsdorf DS Zaharko 《Canadian Metallurgical Quarterly》1980,40(10):3704-3708
Two cyclophosphamide (CP) derivatives, 4-S-(hexane-6-ol)-sulfidocyclophosphamide (C-1) and 4-S-(propionic acid)-sulfidocyclophosphamide (C-2), that hydrolyze spontaneously under physiological conditions to 4-hydroxycyclophosphamide, are compared to CP for antitumor activity in male C57BL/6 x DBA/2 F1 mice with ascites L1210 leukemia or solid Lewis lung carcinoma. When C-1 or C-2 is administered i.p. as a single injection at 10% lethal dose (approximately LD10) to mice bearing L1210 (1 x 10(5) cells i.p.), early treatment produces a 5- to 6-log tumor cell kill and results in substantial numbers of long-term survivors (greater than or equal to 30 days). Such antitumor activity is comparable to that of CP treatment. However, i.p. administration of either sulfido derivative produces liver atrophy and fibrosis of hepatic capsular structures. Hepatotoxicity is eliminated if single-dose C-2 (less than or equal to LD10) is administered i.v.; however, when administered by this route, C-2 results in only a 1-log cell kill of i.v. implanted leukemic cells as compared to the 4-log tumor cell kill obtained with CP given i.v. In addition to hepatotoxicity, C-2 causes an acute and dose-limiting toxicity in mice, manifested by severe muscular spasms and cessation of breathing. In the treatment of advanced L1210, C-2 shows no therapeutic advantage over CP. When mice bearing s.c. Lewis lung carcinoma receive early i.p. treatment with CP, C-1, or C-2, each drug results in long-term tumor-free survivors. However, CP (< LD10) consistently cures all mice, whereas C-1 or C-2 (approximately LD10) produces only 10 to 30% tumor-free survivors. These data suggest that, in the L1210 and Lewis lung tumor systems studied, the two activated CP derivatives offer no therapeutic advantage over CP. In addition, two forms of toxicity occur with these derivatives that do not occur with CP. 相似文献
960.