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Mentally retarded adolescents and MA-matched nonretarded children participated in three experiments designed to examine differences in language-processing efficiency. A compressed speech technique was used in Experiments 1 and 2. Experiment 3 relied on a sentence-picture verification procedure. Our results suggest that retarded and nonretarded individuals differ in the speed with which they are able to execute the semantic-analytic processes but not necessarily the phonological encoding processes that are involved in auditory language comprehension. In addition, the data suggest a possible group difference in the quality of the semantic representation encoded during sentence processing. 相似文献
3.
Evaluation of students undertaking fieldwork education placements is a critical process in the health professions. As training programs and practice evolve, systems for assessing students need to be reviewed and updated constantly. In 1995, staff of the occupational therapy training program at the University of Queensland, Australia decided to develop a new tool for assessing student fieldwork performance. Using an action research methodology, a team developed the Student Placement Evaluation Form, a flexible and comprehensive criterion-referenced evaluation tool. The present paper examines action research as an appropriate methodology for considering real-life organisational problems in a systematic and participatory manner. The action research cycles undertaken, including preliminary information gathering, tool development, trial stages and current use of the tool, are detailed in the report. Current and future development of the tool is also described. 相似文献
4.
Eser Tüfek?i Thomas E Merrill Maria R Pintado John P Beyer William A Brantley 《American journal of orthodontics and dentofacial orthopedics》2004,125(6):733-739
Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant. 相似文献
5.
The goals of the present study were twofold: first, to assess the renal excretory and hormonal responses to chronic water restriction in dogs whose sodium retaining mechanisms had been stimulated through dietary sodium (Na+) deprivation; second, to determine the mediator(s) of the natriuresis which was observed with water restriction in these sodium deprived dogs. Three groups of dogs maintained on a low Na+ diet (5 mEq/day) for two weeks underwent a three day period of water restriction. In normal, intact dogs Group 1 (N = 5), water restriction resulted in a significant increase in Na+ excretion with a net cumulative loss of 26.3 +/- 2.6 mEq over three days. The natriuresis was associated with a significant increase in plasma vasopressin (PAVP) (1.7 to 10.2 pg/mliter) and a significant fall in plasma aldosterone (PALDO) from the levels observed with Na+ restriction alone (24.9 to 12.4 ng/dliter). The natriuresis could not be explained by decreases in food intake as determined by control studies in four dogs. Group 2 (N = 6) dogs had a decrease in PALDO with water restriction that was prevented by means of continuous i.v. aldosterone infusion (6.0 micrograms/kg/day). Dogs in this group failed to demonstrate a natriuresis during three days of water restriction, despite the fact that PAVP rose from 3.3 +/- 0.8 to a peak level of 14.95 +/- 1.9 pg/mliter. Group 3 (N = 6) dogs underwent selective neurohypophysectomy, thus preventing the rise in PAVP during three days of water restriction. In this group, PALDO also remained unchanged from the Na+ deprived level during water restriction, and no natriuresis was observed. We conclude: 1) that the natriuresis which occurs with water restriction is a potent physiological response that occurs even in the Na+ restricted state; and 2) this natriuresis can be explained by a fall in PALDO and not the rise in PAVP. 相似文献
6.
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Haiyung Cheng Jules I. Schwartz Charles Lin Raju D. Amin James R. Seibold Kenneth C. Lasseter David L. Ebel Dominick J. Tocco J. Douglas Rogers 《Biopharmaceutics & drug disposition》1994,15(5):409-418
MK-679 (R(?)-3-((3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl)(3-(dimethylamino)-3-oxopropyl)thio)methyl)thio(propanoic acid) is a potent and specific LTD4-receptor antagonist. The disposition of MK-679 was investigated in a three-way crossover study in 12 healthy males receiving single intravenous doses of 75, 250, and 500 mg of MK-679. A greater than proportional increase in the area under the plasma concentration—time curve of MK-679 was observed with increase in dose. The plasma concentration data for each subject fitted well to the differential equations for a two-compartment model with linear tissue distribution and Michaelis-Menten elimination from the central compartment, indicating that the elimination of MK-679 in humans is saturable. In a previous study, the disposition of MK-679 in humans was also dose-dependent when given together with its S(+)-isomer, L-668,018. Thus, the disposition of MK-679 in humans is dose-dependent regardless of the presence of its stereoisomer. Also, the bioavailability of MK-679 was determined in six healthy males receiving simultaneously an oral dose of 250 mg of MK-679 and intravenous infusion of 1 mg 14C-MK-679. Results of this study indicate that the oral bioavailability of MK-679 is nearly quantitative. 相似文献
8.
9.
D C Merrill 《Urology》1986,28(3):185-189
The Mentor inflatable penile prosthesis (IPP) has been implanted in 206 patients with organic (95.2%) or psychologic (4.8%) impotency. The patients have been followed up for an average of 18.1 (4-42) months. A satisfactory result has been achieved in 98 per cent of these patients. A life analysis of the series shows that 88 per cent of all devices implanted will survive forty-two months without mechanical failure. One hundred sixty-four of these patients had not had previous penile surgery while 42 had had one or more penile prostheses implanted previously. The projected forty-two-month survival for the Mentor prosthesis in these subgroups is 94 per cent and 74 per cent, respectively. The improved life expectancy of the Mentor IPP, compared with the Scott IPP, is due to the superior durability of Mentor's polyurethane cylinders and to the increased reliability of the Mentor snap-on connector system. In this respect, there have been only one cylinder failure and 3 connector failures in the Mentor series. The connector failures occurred early in the series before the development of connector pliers; there have been no connector failures in the last 202 consecutive implantations. Wear-induced tubing leaks, the most common cause of device failure, occurred in 2.9 per cent of all implantations. Tubing failures were more common in patients who have had previous surgery, occurring in 9 per cent of salvage procedures and 1.3 per cent of primary implantations. The reason for the difference in tubing survival in virgin and salvage procedures is unknown; possibly the subcutaneous scar tissue present in secondary surgical procedures increases the chance of tubing segments touching and abrasing each other. Laboratory studies suggest that the nylon-reinforced tubing used in the manufacture of devices implanted since 1985 is more durable than is the standard silicone tubing used in the construction of devices implanted previously. 相似文献
10.
Sajja Lokeswara Rao Mannam Gopichand Sompali Sriramulu Reddy Karri Venkata Ravirala Bala Raju Raju Bhupathiraju Soma Raju Penmetcha Krishnam 《Indian Journal of Thoracic and Cardiovascular Surgery》2004,20(4):173-177
Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass
has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried
out to compare mortality and morbidity in the off-pump and on-pump CABG groups.
Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG
and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for
bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL)
pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared.
Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG
with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12%
although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure
between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001).
Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in
both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in
off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and
hospital stay in OPCAB group. 相似文献