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31.
CJ Laruelle GB Brueren SM Ernst ET Bal GE Mast MJ Suttorp A Brutel de la Rivière TH Plokker 《Canadian Metallurgical Quarterly》1998,79(2):148-152
The effect of bone plug length and Kurosaka screw (DePuy, Warsaw, IN) diameter on graft holding strength of the bone-tendon-bone construct was determined. Random length porcine bone plugs were assigned to fixation with 7 or 9 mm Kurosaka screws. Peak load to failure was determined. There was a significant decrease in peak load to failure of the 5-mm long bone plugs compared with longer bone plugs. No difference was found between longer lengths of bone plug in either the 7- or 9-mm screw diameter groups. The 9-mm diameter screws significantly increased peak load to failure for both 1- and 2-cm bone plug lengths. 相似文献
32.
MJ Marttunen MM Henriksson ET Isomets? ME Heikkinen HM Aro JK L?nnqvist 《Canadian Metallurgical Quarterly》1998,33(131):669-681
The characteristics of male adolescent suicide victims with (n = 84) and without (n = 8) a diagnosable psychiatric disorder were compared. Using psychological autopsy methods--interviews with victims' family members and health care professionals, and review of records (e.g., medical, school, police)-data were collected on all adolescent suicides in Finland during a 12-month period. Compared with adolescents with a psychiatric disorder, those with no disorder tended to come from less disturbed families, had shown less antisocial behavior, and had less frequently utilized health care and social services. Adolescents with no disorder more often communicated suicidal thoughts for the first time just before the suicide, and difficulties with the law (discipline problems) were more common precipitants than among those with a disorder. It was concluded that the process leading to suicide seems to be relatively short among male adolescents with no diagnosable psychiatric disorder. Communication of suicidal intent and problems with discipline are among the few clinical warning signs. 相似文献
33.
PH Dennehy GC Rodgers RL Ward AJ Markwick M Mack ET Zito 《Canadian Metallurgical Quarterly》1996,15(11):1012-1018
OBJECTIVE: To compare the safety and immunogenicity of two dosages of tetravalent rhesus rotavirus vaccine (RRV-TV) and the effect of age at dosing. METHODS: A total of 195 infants were stratified by age into 2 groups, 6 to 12 weeks and 16 to 24 weeks, and randomly assigned to receive a single dose of placebo or RRV-TV containing either 4 x 10(5) or 4 x 10(6) plaque-forming units (pfu). Symptoms were recorded for 5 days after vaccination. Anti-rotavirus IgA and neutralizing antibody to human rotavirus serotypes G1 to G4 and RRV were measured in serum obtained pre- and postvaccination. RESULTS: Rates of fever > 38 degrees C (9%), diarrhea (6%) and vomiting (8%) were similar in all groups. IgA (69% vs. 49%, P = 0.02) and RRV (85% vs. 66%, P = 0.004) seroconversion rates were significantly higher in the 4 x 10(6) pfu vaccine group as were antibody titers to RRV (440.2 vs. 263.7, P = 0.04). Older infants demonstrated significantly higher seroconversion rates and antibody titers for IgA (71% vs. 52%, P = 0.03; and 110.6 vs. 54.8, P = 0.004) and RRV (92% vs. 66%, P = 0.05 and 498.3 vs. 205.6, P = 0.01) at either dose level than did the younger infants. There were no significant differences in seroconversion rates or antibody titers to human rotavirus types G1 to G4 between the two vaccination groups. CONCLUSIONS: RRV-TV at a dose of 4 x 10(6) pfu can be safely administered to infants 6 to 24 weeks of age. A single dose of 4 x 10(6) pfu of RRV-TV was significantly more immunogenic than a single dose of 4 x 10(5) pfu but did not improve responses to the human serotypes. Older vaccine recipients demonstrated significantly higher IgA and neutralizing antibody seroconversion rates and antibody titers than younger infants independent of dosage. 相似文献
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Conducted 4 experiments with 4 male rhesus monkeys in which food was diverted from the stomach, the small intestine, or both. Results demonstrate that (a) food acting at the pregastric level was not sufficient to produce normal-sized meals, (b) accumulation of food in the small intestine was necessary to produce normal-sized meals, and (c) a potent preabsorptive or postabsorptive satiety signal originated at the intestinal level. It is concluded that this unidentified satiety signal is sufficient to elicit satiety, can be dissociated from gastric emptying, and does not require the presence of gastic distention to operate. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
ED Kouvelas CE Savakis ET Tzebelikos G Bonatsos S Mitrossilis 《Canadian Metallurgical Quarterly》1976,32(9):1136-1138
The specific activity of histamine methyltransferase of rat brain increases rapidly from the 16th until the 25th day of gestation (7 days after birth). The specific activity of phenylethanolamine-N-methyl-transferase shows a rapid increase during the 1st and the 2nd week after birth, the adult values being obtained by the end of the 2nd week. 相似文献
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Invariant object recognition in the visual system with error correction and temporal difference learning 总被引:1,自引:0,他引:1
It has been proposed that invariant pattern recognition might be implemented using a learning rule that utilizes a trace of previous neural activity which, given the spatio-temporal continuity of the statistics of sensory input, is likely to be about the same object though with differing transforms in the short time scale. Recently, it has been demonstrated that a modified Hebbian rule which incorporates a trace of previous activity but no contribution from the current activity can offer substantially improved performance. In this paper we show how this rule can be related to error correction rules, and explore a number of error correction rules that can be applied to and can produce good invariant pattern recognition. An explicit relationship to temporal difference learning is then demonstrated, and from this further learning rules related to temporal difference learning are developed. This relationship to temporal difference learning allows us to begin to exploit established analyses of temporal difference learning to provide a theoretical framework for better understanding the operation and convergence properties of these learning rules, and more generally, of rules useful for learning invariant representations. The efficacy of these different rules for invariant object recognition is compared using VisNet, a hierarchical competitive network model of the operation of the visual system. 相似文献
39.
H Tanaka CA Desouza PP Jones ET Stevenson KP Davy DR Seals 《Canadian Metallurgical Quarterly》1997,83(6):1947-1953
Using a meta-analytic approach, we recently reported that the rate of decline in maximal oxygen uptake (VO2 max) with age in healthy women is greatest in the most physically active and smallest in the least active when expressed in milliliters per kilogram per minute per decade. We tested this hypothesis prospectively under well-controlled laboratory conditions by studying 156 healthy, nonobese women (age 20-75 yr): 84 endurance-trained runners (ET) and 72 sedentary subjects (S). ET were matched across the age range for age-adjusted 10-km running performance. Body mass was positively related with age in S but not in ET. Fat-free mass was not different with age in ET or S. Maximal respiratory exchange ratio and rating of perceived exertion were similar across age in ET and S, suggesting equivalent voluntary maximal efforts. There was a significant but modest decline in running mileage, frequency, and speed with advancing age in ET. VO2 max (ml . kg-1 . min-1) was inversely related to age (P < 0.001) in ET (r = -0.82) and S (r = -0.71) and was higher at any age in ET. Consistent with our meta-analysic findings, the absolute rate of decline in VO2 max was greater in ET (-5.7 ml . kg-1 . min-1 . decade-1) compared with S (-3.2 ml . kg-1 . min-1 . decade-1; P < 0. 01), but the relative (%) rate of decline was similar (-9.7 vs -9. 1%/decade; not significant). The greater absolute rate of decline in VO2 max in ET compared with S was not associated with a greater rate of decline in maximal heart rate (-5.6 vs. -6.2 beats . min-1 . decade-1), nor was it related to training factors. The present cross-sectional findings provide additional evidence that the absolute, but not the relative, rate of decline in maximal aerobic capacity with age may be greater in highly physically active women compared with their sedentary healthy peers. This difference does not appear to be related to age-associated changes in maximal heart rate, body composition, or training factors. 相似文献
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