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The purpose of this study was to examine the effects of object self-stimulation on the task-interrupting self-stimulatory behavior and prevocational work responses of a 13-year-old autistic boy. Using a multiple-baseline design across three diferent prevocational tasks, a systematic manipulation of object self-stimulation was associated with increases in correct rates and decreases in task-interrupting self-stimulatory behaviors. An analysis of these data indicates that self-stimulatory behavior may be shaped to facilitate performance proficiencies. Social validation information suggests that favorable generalized responding had occurred. On the basis of findings from this study, future research needs are discussed. 相似文献
43.
Behavior, genetics and biochemistry of an allele of the mutant mouse spastic, spaAlb 总被引:1,自引:0,他引:1
A new autosomal recessive mutation, characterized by an early defect in righting reflex and stiffened gait, progression to severe spasticity, tremor and rigidity, and death before weaning, appeared spontaneously on the C57BL/6 background. It was shown to be an allele of the mutant spastic spa, and shall be known as spaAlb. Mutant levels of [3H]strychnine binding are less than 10% of control levels in the brainstem and spinal cord. Autoradiographic examination of the distribution of [3H]strychnine binding sites in the mutant confirm a greatly reduced level of binding compared to control in all areas of the spinal cord, brainstem, and midbrain. 相似文献
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45.
The first case report of systemic evenomation by the five-ringed brown snake, Pseudonaja modesta, is presented. The patient had mild general symptoms of envenomation only, with no coagulopathy or evidence of paralysis. Data on P. modesta venom is presented, which shows an absence of a coagulant component in this venom. The venom gives a positive reaction to brown snake venom in the CSL Venom Detection Kit. 相似文献
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47.
Randee Breiterman White 《Nephrology nursing journal》2004,31(4):432-435
Nonadherence is common in the U.S. dialysis population. No single strategy has been definitely proven to yield universal and/or lasting improvements in adherence. However, using a patient-centered approach, including the removal of barriers to adherence, ongoing education, and cognitive behavioral strategies, may generate increased opportunities for patients and the nephrology staff to improve both adherence and outcomes. 相似文献
48.
49.
D Purves L E White 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(18):8339-8342
Faced with an unobstructed view, both foveas can be readily aligned with a distant visual target. The minor difference in the view of the two eyes (which arises from slightly different lines of sight) presents no special problem and is, indeed, the basis of stereopsis. However, when obstructing objects are present in the foreground, the view provided by one eye becomes wholly or partially incompatible with the view of the other. We have investigated how we cope with this everyday situation by having volunteers observe distant targets through a fenestrated screen. In this circumstance, subjects naturally position themselves to view a target of interest with one eye--usually the right eye. This monocular habit in normal viewing reinforces other evidence for the unorthodox idea that visual perception arises from a union in consciousness of monocular images that are elaborated independently. 相似文献
50.
Venous duplex imaging: should it replace hemodynamic tests for deep venous thrombosis? 总被引:2,自引:0,他引:2
A J Comerota M L Katz L L Greenwald E Leefmans M Czeredarczuk J V White 《Journal of vascular surgery》1990,11(1):53-9; discussion 59-61
Noninvasive diagnosis of deep venous thrombosis has traditionally relied on detection of alterations in venous hemodynamics. Although phleborheography is among the most sensitive tests, it is inadequate for diagnosing infrapopliteal and nonocclusive proximal thrombi and for surveillance of patients at high risk for deep venous thrombosis. Venous duplex imaging is a new technique being rapidly accepted, however, without the same critical analysis given to previous diagnostic modalities. The purpose of this study is to evaluate the diagnostic acumen of venous duplex imaging compared to phleborheography and ascending phlebography in two distinct patient groups, and to determine whether patient selection, and thus the location or magnitude of thrombi have significant influence on these diagnostic tests. One hundred ten extremities in 103 patients were prospectively evaluated with venous duplex imaging, phleborheography, and ascending phlebography within the same 24-hour period. Patients were categorized into one of two groups: Diagnostic--patients evaluated because of clinical suspicion of acute deep venous thrombosis; and Surveillance--patients at high risk of postoperative deep venous thrombosis after total joint replacement, but not symptomatic. Patients in the diagnostic group had a greater frequency of deep venous thrombosis (p less than 0.001) and significantly more occluding above-knee thrombi (p = 0.054) compared to those in the surveillance group. Phleborheography detected 73% (27/37) of above-knee thrombi in the diagnostic group compared to 29% (2/7) in the surveillance group (p = 0.036). This difference was not noted with venous duplex imaging, which detected 100% of above-knee thrombi in both diagnostic and surveillance groups and 78% (7/9) of all below-knee thrombi.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献