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71.
The amoebicidal activity of a contact lens multipurpose disinfecting solution (MPDS) containing polyquaternium-1 and myristamidopropyl dimethylamine was compared to a disinfection/neutralisation peroxide system against Acanthamoeba castellanii and Acanthamoeba polyphaga trophozoites and cysts. A quantitative microtitre method was used to evaluate the solutions. The MPDS showed similar amoebicidal activity to the disinfection/neutralisation peroxide system against the trophozoites of both species and equal or more rapid activity against the cysts of both species.  相似文献   
72.
[Correction Notice: An erratum for this article was reported in Vol 28(2) of Health Psychology (see record 2009-03297-015). There was a typographical error in the text on page 521, in the first sentence of the first full paragraph. The corrected sentence is provided in the erratum.] Objective: To assess the effects of a communication skills training program for physicians and patients. Design: A randomized experiment to improve physician communication skills was assessed 1 and 6 months after a training intervention; patient training to be active participants was assessed after 1 month. Across three primary medical care settings, 156 physicians treating 2,196 patients were randomly assigned to control group or one of three conditions (physician, patient, or both trained). Main Outcome Measures: Patient satisfaction and perceptions of choice, decision-making, information, and lifestyle counseling; physicians' satisfaction and stress; and global ratings of the communication process. Results: The following significant (p  相似文献   
73.
50 Ss (mean age 51.1 yrs) with essential hypertension were randomly assigned to 1 of 4 conditions: individualized relaxation, group relaxation (GR), GR plus contingency contracting (CC) for home practice, or a waiting list. Treated Ss were given tape players and relaxation tapes and were instructed to practice daily for 10 wks. Unknown to the Ss, the tape players had a concealed capacity to electronically monitor the amount of relaxation practice. All relaxation conditions showed significantly greater reductions in both systolic and diastolic blood pressure than waiting-list controls but did not differ from each other. Monitored relaxation predicted systolic but not diastolic changes. Self-reports exceeded monitored practice by 91%, and only 32% of the Ss averaged 1 practice/day. GR plus CC Ss showed the lowest rate of practice across most weeks. Rated self-efficacy, age, and pretreatment expectations of benefit were positively correlated with relaxation compliance. Data support the use of relaxation for hypertension but suggest that noncompliance is common in both individual and group relaxation training. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
75.
The use of stem cells for reparative medicine was first proposed more than three decades ago. Hematopoietic stem cells from bone marrow, peripheral blood and human umbilical cord blood (CB) have gained major use for treatment of hematological indications. CB, however, is also a source of cells capable of differentiating into various non-hematopoietic cell types, including neural cells. Several animal model reports have shown that CB cells may be used for treatment of neurological injuries. This review summarizes the information available on the origin of CB-derived neuronal cells and the mechanisms proposed to explain their action. The potential use of stem/progenitor cells for treatment of ischemic brain injuries is discussed. Issues that remain to be resolved at the present stage of preclinical trials are addressed.  相似文献   
76.
The viability of developing an SiC fibre-reinforced titanium/titanium aluminide hybrid matrix composite was explored. The hybrid composites are expected to be used at temperatures beyond those attainable in conventional titanium matrix composites while improving the damage tolerance of the titanium aluminide matrix composites. The room-temperature mechanical characteristics studied were tensile strength, fracture toughness, low-cycle fatigue life and fatigue crack growth rate. The mechanisms of damage initiation and propagation under various loading conditions were also characterized. The directions for developing a satisfactory composite with hybrid titanium/titanium aluminide matrix are also addressed.  相似文献   
77.
Construct validity is one of the most central concepts in psychology. Researchers generally establish the construct validity of a measure by correlating it with a number of other measures and arguing from the pattern of correlations that the measure is associated with these variables in theoretically predictable ways. This article presents 2 simple metrics for quantifying construct validity that provide effect size estimates indicating the extent to which the observed pattern of correlations in a convergent-discriminant validity matrix matches the theoretically predicted pattern of correlations. Both measures, based on contrast analysis, provide simple estimates of validity that can be compared across studies, constructs, and measures meta-analytically, and can be implemented without the use of complex statistical procedures that may limit their accessibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
This study determined the test-retest reliability of the polysomnographic findings in narcolepsy. The diagnosis of narcolepsy was based on clinical symptoms and polysomnographic signs. Control subjects were screened before participation and were split based on their screening multiple sleep latency test (MSLT) into high- and low-MSLT groups. Subjects completed two polysomnographic evaluations with at least 5 days between laboratory tests. Narcoleptics had lower sleep efficiencies and high stage 1% when compared to the low MSLT control group. They had more awakenings and less stage 2% than the control groups. Narcoleptics had a shorter latency to 1 when compared to the high-MSLT group but comparable to that of the low-MSLT group. Narcoleptics had a higher number of sleep-onset rapid eye movement periods (SOREMPs) than both control groups. The MSLT scores were stable across the two evaluations and showed a statistically significant correlation. Twenty-eight of the 30 narcoleptic subjects had two or more SOREMPs on reevaluation. None of the controls had multiple SOREMPs. Thus, multiple SOREMPs were shown to be a reliable finding in patients with narcolepsy.  相似文献   
79.
Changes in the health care delivery system have obliged rehabilitation service providers to consider alternatives to the traditional model of comprehensive acute inpatient rehabilitation. An option of growing popularity among third-party payers is subacute rehabilitation. This type of rehabilitation is usually provided within a skilled nursing home, provides fewer hours of therapeutic intervention, and uses less professional staff, but may achieve similar outcomes. As subacute rehabilitation has grown, rehabilitation psychologists have been used in these settings, but uncertainties exist as to appropriate roles and reimbursement opportunities. This article provides a framework for understanding the current status of subacute rehabilitation as a part of the rehabilitation continuum of care and how rehabilitation psychologists can maximize their effectiveness in this environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
One of the main challenges in implementing wireless sensor networks (WSN) is to minimize power consumption in order to maximize network lifetime. To accomplish this, we derive an upper bound on the average network lifetime. The upper bound was derived for a code division multiple access (CDMA) communication system. The communication procedure that consumes most of the energy is transmission. But, it is possible to reduce energy consumption by increasing the antenna gain of the base station which collects information from the sensors. However, a problem that arises is that the spot size of high gain antenna is smaller than low gain antenna and as a result the base station provides only partial coverage to the network, which is obviously an undesirable situation. Therefore we propose to shape the base-station antenna gain in such a way that maximizes network lifetime, by taking advantage of the spatial nonuniformity distribution of the sensors on the ground.  相似文献   
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