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排序方式: 共有386条查询结果,搜索用时 15 毫秒
1.
Eric E Rasmussen Autumn Shafer Malinda J. Colwell Shawna White Narissra Punyanunt-Carter Rebecca L. Densley 《Journal of Children and Media》2016,10(4):443-461
This study explored the relationship between active mediation, exposure to Daniel Tiger’s Neighborhood, and key indicators of preschoolers’ social and emotional development. One hundred and twenty-seven children aged 2–6 either watched or did not watch 10 episodes of Daniel Tiger’s Neighborhood over a two-week period. Results revealed that preschoolers who watched the program exhibited higher levels of empathy, self-efficacy, and emotion recognition when their regular TV-watching experiences are frequently accompanied by active mediation. This was especially true for younger preschoolers and preschoolers from low-income families. Implications for policy-makers, parents, producers of prosocial programming, and educators are discussed. 相似文献
2.
A series of C(3)-cyclopropyl cephems and carbacephems has been prepared by palladium catalyzed addition of diazomethane to the corresponding C(3)-vinyl derivatives. The phenylglycyl cyclopropyl cephem derivatives exhibit better Gram-positive activity than cephalexin or cefaclor, while the aminothiazole oxime cyclopropyl cephem derivatives were not as active as the corresponding C(3)-vinyl cephems. 相似文献
3.
Clare E Herbert Martin A Ebert D Barclay David S Whittall David J Joseph Chris S Harper Nigel A Spry 《Medical Dosimetry》2003,28(1):27-30
A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate. 相似文献
4.
Lentell G Cashman PA Shiomoto KJ Spry JT 《The Journal of orthopaedic and sports physical therapy》1988,10(5):177-183
The purpose of this study was to compare the effect of knee position on the magnitude of torque generated during the isokinetic movements of inversion and eversion at the ankle. Mean peak torque values at 30 and 120 degrees /sec were collected from 12 subjects, ages 21-31, from two test positions. The knee was stabilized in 10 degrees of flexion for the first test position and 70 degrees for the second. Additionally, mean peak amplitude of hamstring motor unit action potentials was compared between the two test positions to demonstrate differences in hamstring activity. At both speeds, mean peak torque values of the inversion-eversion movements, as well as mean peak amplitude of hamstring motor unit action potentials, was significantly lower in 10 degrees compared to 70 degrees of knee flexion (p < 0.01). It was concluded that isokinetic testing at the ankle with the knee in a close packed position, near full extension, provides a more valid representation of isolated muscular performance than testing with the knee in a loose packed position of midrange flexion.J Orthop Sports Phys Ther 1988;10(5):177-183. 相似文献
5.
The effects of complement activation by cobra venom factor on the migration of T and B lymphocytes into rat thoracic duct lymph.
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Experiments were done to see whether C3 or C3-split products are involved in lymphocyte recirculation, with particular reference to B lymphocytes which have C3b receptors. Rats were injected with cobra venom factor (CVF), and the output of subclasses of lymphocytes was measured in thoracic duct lymph in hourly collections during the subsequent 24 h. During the period of acute C3 activation which lasted for 2-8 h, the output of lymphocytes decreased by 47%, but returned to normal at later times, when C3 levels were reduced to less than 20% normal. There was no effect on the output of C3b receptor lymphocytes, and this receptor was not blocked probably because initial C3 levels in lymph were only 13% of blood levels, so that only small amounts of C3b were generated in lymph. When these lymphocytes were labelled and injected i.v. they migrated with the slow rate which is characteristic of normal B lymphocytes. The main effect of CVF was to reduce the output of T lymphocytes by 58% during the phase of acute C3 activation. When normal thoracic duct lymphocytes were labelled and injected, their rate of reappearance in thoracic duct lymph was only reduced during this phase. It was concluded that recirculation of lymphocytes is not C3 dependent, and that insufficient C3b is generated in lymphoid tissues to block C3b receptors on B lymphocytes during periods of rapid C3 activation. However the migratory rate of T lymphocytes through these tissues is reduced during this period, and it is suggested that this may be due to an effect of C3 split products on macrophages which lie along T-lymphocyte traffic routes. 相似文献
6.
7.
OBJECTIVES: To compare the costs of monitoring stable glaucoma patients by community optometrists and hospital ophthalmologists. METHODS: A cost analysis was conducted alongside a randomised controlled trial which compared the accuracy and acceptability of measurement in each form of care. The viewpoints of the health service and of patients were considered. Costs were assessed using a number of different methods. Sensitivity analysis was conducted for key variables. RESULTS: The baseline analysis reflected heavily the different length of time between follow-up in the two arms of the trial (10 months (average) for hospital, 6 months for optometrists). It showed annual cost per patient for hospital ophthalmologists varied from 14.50 pounds to 59.95 pounds, and community optometrist costs varied from 68.98 pounds to 108.98 pounds. Assuming a 6-month follow-up interval for the hospital ophthalmologists, costs varied from 24.16 pounds to 99.92 pounds. CONCLUSIONS: Recommendations about the least costly form of follow-up must depend on the context in which the decision is being taken and the scale of change envisaged. If the aim is to recoup resources from hospitals in order to pay for monitoring in the community, community monitoring is unlikely to be the least costly option. 相似文献
8.
Hamilton C Poulsen M Walker Q Krawitz H Hindley A Spry N Peters L Lamb D Denham J Steigler A 《Australasian radiology》1999,43(2):227-232
The Trans-Tasman Radiation Oncology Group (TROG) initiated a randomized trial, testing accelerated (twice daily) radiotherapy against conventional radiotherapy for stage III and stage IV squamous cell carcinoma of the head and neck in 1991. In 1996, the Trial Management Committee arranged for a technical audit of 76 cases from 11 institutions, conducted by investigators from interstate institutions. A 10% unacceptable protocol violation rate was detected, which compares favourably with initial Radiation Therapy Oncology Group (RTOG) experience in the late 1970s. Infrastructural deficits with poor quality of documentation, incomplete retrieval of films and document return have been demonstrated in some cases. The Trans-Tasman Radiation Oncology Group is actively pursuing procedural and resourcing issues in order to redress this and is actively expanding its Quality Assurance (QA) Programme with an intercentre dosimetry study. Ultimately, comprehensive clinical and technical QA site visits are planned. 相似文献
9.
The Bristol Shared Care Glaucoma Study: reliability of community optometric and hospital eye service test measures. 总被引:1,自引:0,他引:1
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P G Spry I C Spencer J M Sparrow T J Peters S T Brookes S Gray I Baker J E Furber D L Easty 《The British journal of ophthalmology》1999,83(6):707-712
BACKGROUND/AIMS: Primary open angle glaucoma patients and glaucoma suspects make up a considerable proportion of outpatient ophthalmological attendances and require lifelong review. Community optometrists can be suitably trained for assessment of glaucoma. This randomised controlled trial aims to assess the ability of community optometrists in the monitoring of this group of patients. METHODS: Measures of cup to disc ratio, visual field score, and intraocular pressure were taken by community optometrists, the hospital eye service and a research clinic reference "gold" standard in 405 stable glaucoma patients and ocular hypertensives. Agreement between and within the three centres was assessed using mean differences and intraclass correlation coefficients. Tolerance limits for a change in status at the level of individual pairs of measurements were also calculated. RESULTS: Compared with a research clinic reference standard, measurements made by community optometrists and those made in the routine hospital eye service were similar. Mean measurement differences and variability were similar across all three groups compared for each of the test variables (IOP, cup to disc ratio, and visual field). Overall, the visual field was found to be the most reliable measurement and the cup to disc ratio the least. CONCLUSIONS: Trained community optometrists are able to make reliable measurements of the factors important in the assessment of glaucoma patients and glaucoma suspects. This clinical ability should allow those optometrists with appropriate training to play a role in the monitoring of suitable patients. 相似文献
10.
Sean A Bydder David J Joseph Nigel A Spry 《Journal of Medical Imaging and Radiation Oncology》2004,48(1):25-28
The abstract to publication ratio (APR) is a measure of the quality of scientific meetings. The aim of the present study was to determine the publication rate of abstracts presented at annual Royal Australian and New Zealand College of Radiologists (RANZCR) conferences, and to identify the publishing journals. All free paper research abstracts (oral or poster) presented by RANZCR radiologists, radiation oncologists and trainees at the four consecutive meetings between 1996 and 1999 were identified retrospectively from conference programmes. The PubMed database ( http:www.ncbi.nlm.nih.govPubMed ) was searched to determine whether or not the abstract had been published as a full paper. Of the 480 free paper research abstracts, 168 (35%) had been published as full articles. The overall abstract to publication ratio for radiology was 29% and for radiation oncology was 41%. Papers were published in a variety of journals but Australasian Radiology accounted for 27%. The mean time between presentation and publication was 16.5 months (median 17 months). These overall abstract to publication ratios are lower than those reported for overseas‐based meetings in each respective area. Guidelines to scientific committees could increase the APR by more rigorous selection of abstracts. Future research should look at barriers to the publication of research findings, and identify ways to assist the publication process. 相似文献