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951.
M. C. Constantinou M. D. Symans 《The Structural Design of Tall and Special Buildings》1993,2(2):77-92
This paper presents a review of supplemental damping devices used for the control of the seismic response of structures. The mechanical properties of these devices are discussed and considerations in the design of energy absorbing systems are presented. 相似文献
952.
Comments on K. S. Pope and V. A. Vetter's (see record 1992-25072-001) survey results on ethical dilemmas faced by members of psychology organizations. The author notes 2 specific concerns about psychology organizations accepting financial sponsorship from organizations that financially benefit from the sponsorship: the potential for a conflict of interest and the financial burden on the clients of psychology organizations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
953.
P Granone G Cardillo E Rumi D D'Ugo C Rumi S Ciletti S Margaritora D Terribile A Picciocchi 《Canadian Metallurgical Quarterly》1993,7(7):351-355
Fresh surgical specimens of tumors from 60 patients with previously untreated non-small cell lung carcinoma (NSCLC) who underwent radical surgery between January 1991 and October 1992 were investigated by means of flow-cytometry. The nuclear DNA measurement was carried out using a Facscan (Becton, Dickinson, USA). Analysis of the DNA content was performed in all 60 patients whilst cell cycle analysis was possible in 41 cases (68.3%). Forty-two of the 60 cases (70%) were aneuploid and 18 (30%) were diploid. The overall mean value of DNA index was 1.5. Diploid NSCLC were compared with aneuploid tumors: no significant differences in age distribution, sex ratio, histology and staging were found between the two groups (P > 0.05). An S-phase proportion of more than 10% was found in 30 out of 41 patients (73.2%). Early cancer deaths were reported in four patients (6.6%): the aneuploidy rate was very close in these patients (75%) and in the remaining surviving patients (69.6%). An S-phase proportion of more than 10% was found in 100% of early cancer deaths and in 70.2% of the remaining cases; such a difference seems of some importance although it was not statistically significant (P = 0.071). In conclusion, flow-cytometry studies seem to be a useful tool in the understanding of the biological behavior of patients with NSCLC. In the present prospective report there were no significant correlations between DNA measurements and clinical outcome, however, these results suggest that a high S-phase proportion should be seen as a possible prognostic indicator.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
954.
S Knecht M Deppe EB Ringelstein M Wirtz H Lohmann B Dr?ger T Huber H Henningsen 《Canadian Metallurgical Quarterly》1998,29(6):1155-1159
BACKGROUND AND PURPOSE: Since functional transcranial Doppler ultrasonography (fTCD) allows convenient and fully automated quantification of language lateralization, it seems ideal for longitudinal studies of perfusion changes during deterioration as well as recovery of language functions. However, during serial examinations, the technical, stochastic, and physiological variabilities of cerebral blood flow velocities (CBFV) have to be considered. Therefore, before fTCD is accepted as a tool for evaluation of changes in lateralization in the diseased state, its reliability in healthy subjects needs to be determined. METHODS: We performed fTCD during a word generation task based on a previously validated technique with automated calculation of the averaged CBFV differences in the middle cerebral arteries providing an index of lateralization (LI). RESULTS: (1) The accuracy of the LI as assessed by the confidence interval was better than 1% of the mean hemispheric difference. (2) On repeated examination, LIs obtained from 10 subjects showed a high test-retest reproducibility (Pearson product moment correlation coefficient r = 0.95, P < 0.0001). (3) On 10 repeated assessments of LI in the same subject, no practice effects were detected. CONCLUSIONS: Functional TCD is a suitable and very robust tool for the longitudinal quantitative measurement of cerebral language lateralization. 相似文献
955.
MG Tozzi-Ciancarelli C Di Massimo G Ascani A Corbacelli 《Canadian Metallurgical Quarterly》1998,18(2-3):151-156
A number of retinal proteins are phosphorylated by a variety of kinases, resulting in well-known regulatory effects. The identity and role of corresponding phosphatases is less clear. We simultaneously measured the activity of serine/ threonine protein phosphatases type 1, 2A and 2C in bovine retinae. The enzymes were classified according to substrate specificity, divalent cation requirement and the effect of phosphatase subtype-specific inhibitors. The total- and specific activity of phosphatase type 2A was prevalent. Type 2C was 10-fold less abundant. 80% of type 1 and 50% of type 2A and type 2C, respectively, were soluble. An economic purification scheme was developed. We demonstrated the presence of phosphatase isozymes 2Calpha and 2Cbeta in bovine rod outer segments by enzymatic analysis as well as immunological techniques. The results suggest a yet unknown role of phosphatase type 2C in phototransduction. On the other hand, the immense amount of protein phosphatases found to be soluble - therefore not associated with rod outer segment membranes - points towards participation of these enzymes in the process of visual transduction not considered thus far. 相似文献
956.
957.
OBJECTIVE: To describe pediatric housestaff resuscitation experience and their ability to perform key resuscitation skills. DESIGN: Cohort study of 63 pediatric residents in a university-based training program. PARTICIPANTS AND METHODS: Investigators observed, scored, and timed resident performance on 4 key resuscitation skills. Cognitive ability was tested with 4 written scenarios. Housestaff provided self-reports of the number of months since their last American Heart Association Pediatric Advanced Life Support course, number of mock and actual codes attended, number of times skills were performed, and self-confidence with respect to resuscitation. RESULTS: A total of 45 pediatric residents (71%) participated. Median cognitive score was 5 (range, 1-5). Of all residents, 44 (97%) successfully bag mask-ventilated the mannequin; 24 (53%) and 36 (80%) used the correct bag and mask size, respectively. Thirty-nine residents (87%) placed a tube in the mannequin trachea, 12 (27%) checked that suction was working prior to intubation, and 30 (67%) chose the correct endotracheal tube size. Forty residents (89%) discharged the defibrillator, and 25 (56%) and 32 (71%) correctly chose asynchronous mode and infant paddles, respectively. Thirty-eight residents (84%) inserted an intraosseous line; 35 (78%) had correct placement. Median times for successful skill completion were 83 seconds for bag mask ventilation, 136 seconds for intubation, 149 seconds for defibrillation, and 68 seconds for intraosseous line placement. CONCLUSION: Pediatric housestaff previously trained in pediatric advanced life support were generally able to reach the end point of 4 key resuscitation skills but less frequently performed the specific subcomponents of each skill. This poor performance and the prolonged time to skill completion suggest the need for greater attention to detail during training. 相似文献
958.
MI Matee EF Lyamuya E Simon EC Mbena C Kagoma LP Samaranayake F Scheutz 《Canadian Metallurgical Quarterly》1996,73(5):292-294
The present study, based on 158 HIV seropositives and 167 HIV seronegatives, demonstrates that saliva collected with the Omni-SAL device and tested with GACELISA (an IgG antibody capture ELISA) is an effective non-invasive alternative to serum for anti-HIV IgG antibody screening. The study also shows that a conventional serum Western blot kit can be used, with slight modifications, for confirmatory testing of saliva specimens. Collecting saliva with the Omni-SAL device had a very good acceptance rate among Tanzanian subjects, and although this diagnostic method is not yet known by the general public, 65% of the study participants preferred to give saliva instead of blood for HIV testing. 相似文献
959.
In a prospective study of 79 patients with arthrographically verified acute ruptured lateral ankle ligaments we have evaluated the long-term results of three different treatments: operation and walking-cast, walking-cast alone and elastic bandage. The average follow-up period was 11 (9-13) years, and 32 parameters concerning interview, clinical and radiographic examinations were statistically analysed. The three kinds of treatment were found to be equal, since only one parameter showed significant difference at a 5% level using Fisher's exact and the Mann-Whitney test, and no difference by using the Kruskal-Wallis test for homogeneity. Residual disabilities and late complications, such as instability, pain on activity, and the number of secondary ligament reconstructions and talocrural arthroses were low. It was concluded that nonoperative treatment provided adequate results even after a decade. 相似文献
960.