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61.
This paper examines temporal changes in the organisation of the cytoskeleton within isolated articular chondrocytes cultured
for up to 7 days in agarose constructs. Fluorescent labelling and confocal microscopy were employed to visualise microtubules
(MT), vimentin intermediate filaments (VIF) and actin microfilaments (AMF). To quantify the degree of cytoskeletal organisation
within populations of cells, a novel image analysis technique has been developed, and fully characterised. Organisation was
quantified in terms of an Edge Index, which reflects the density of ‘edges’ present within the confocal images as defined
by a Sobel digital filter. This parameter was shown to be independent of image intensity and, for all three cytoskeletal components,
was validated statistically against a visual assessment of organisation. Both MT and VIF exhibited fibrous networks extending
throughout the cytoplasm, while AMF appeared as punctate units associated with the cell membrane. The use of the Edge Index
parameter revealed statistical significant temporal variation, in particular associated with VIF and AMF. These findings indicate
the possibility of cytoskeletal mediated temporal variation in many aspects of cell behaviour following isolation from the
intact tissue. Furthermore, the image analysis techniques are likely to be useful for future studies aiming to quantify changes
in cytoskeletal organisation. 相似文献
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64.
Cold application is commonly used before strenuous exercise due to its hypalgesic effects. Some have questioned this procedure because of reports that cold may reduce isokinetic torque. However, there have been no investigations of actual physical performance following cold application. The purpose of this study was to determine if a 20-minute ice immersion treatment to the foot and ankle affected the performance of three agility tests: the carioca maneuver, the cocontraction test, and the shuttle run. Twenty-four male athletic subjects were tested during two different treatment sessions following an orientation session. Subjects were tested following a 20-minute 1°C ice immersion treatment to the dominant foot and ankle and 20 minutes of rest. Following each treatment, subjects performed three trials of each agility test, with 30 seconds rest between each trial, and 1 minute between each different agility test. The order in which each subject performed the agility tests was determined by a balanced Latin square. A MANOVA with repeated measures was used to determine if there was an overall significant difference in the agility times recorded between the cold and control treatments and if the order of the treatment sessions affected the scores. Although the mean agility time scores were slightly slower following the cold treatment, cooling the foot and ankle caused no difference in agility times. Also, there was no difference resulting from the treatment orders. We felt that the slightly slower scores may have been a result of tissue stiffness and/or subject's apprehension immediately following the cold treatment. Cold application to the foot and ankle can be used before strenuous exercise without altering agility. 相似文献
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66.
In 1989, Trent Regional Health Authority set up a Commission to enquire into the organization of day case surgery and encourage its use. Improved methods for measuring and comparing day surgical activity were developed using routine data sources. These revealed even greater variation between hospitals and specialties in the amount of day surgery performed than did the usual analyses. Arrangements for day surgery differed considerably between specialties. Few theatres, beds, or surgeons' sessions were dedicated to day surgery, but general surgery and gynaecology used dedicated facilities more than other specialties such as ENT and ophthalmology. The Commission visited each hospital and found that day case facilities, organization and resources were poor in many of them. It was able to make specific recommendations for improvements. Day case surgery increased substantially over the period that the Commission operated, most hospitals reported that it had influenced changes in day surgery and that it had been useful, especially for local managers. Schemes to increase day surgery were funded. Highlights two elements for managing change: the need for good information about a problem, and the need to extend ownership of the issue throughout the organization. 相似文献
67.
Junkins EP Knight S Lightfoot AC Cazier CF Dean JM Corneli HM 《The Journal of school health》1999,69(10):409-412
68.
Previous research has suggested that a relationship exists between craniofacial morphology and tooth wear. The primary objective of this study was to determine whether an individual's craniofacial morphology during childhood is related to the degree of tooth wear that occurs in that same individual's adult dentition. Pretreatment orthodontic records taken during the mixed dentition (T1) and follow-up records taken an average of 20 years later (T2) were available for 165 orthodontic patients. Incisal/occlusal tooth wear was measured on a tooth-by-tooth basis from T1 and T2 casts using a four-category scoring system. Measures of craniofacial morphology were made from the T1 lateral cephalometric radiograph. Multiple regression analysis indicated that adult wear was associated with the T1 cephalometric measures of ANB (p = 0.017) and the interaction between ramal height and sex (p = 0.039). These results suggest that the craniofacial morphology observed during childhood has a small but significant relationship to adult tooth wear. 相似文献
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Three populations active in human spontaneous cytotoxicity have been identified. Two of these are E-rosette positive, and differ in their adherence to nylon wool. The third is E-rosette negative. The E-rosette positive fraction which does not adhere to nylon consistently does not lyse a breast-cancer-derived target, MDA-157. When tested simultaneously on 4 other tumour target cells lines--Raji, Chang, K562 and Molt 4--however, all three populations are cytolytic. The MDA-157 target is consistently lysed by a nylon-adherent T-cell fraction, irrespective of whether the E rosettes are formed under optimal or the limiting conditions giving only "high-affinity" T cells. The observation that a given effector fraction can lyse one target but not another, whereas other fractions are cytolytic on both, implies that different targets may differentiate effector populations differing in their lytic mechanism. 相似文献