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The study of the underground parts of plants is often difficult, and as a result roots are often treated as homogeneous physiological entities with respect to root respiration. In this study we demonstrate a partitioning of respiration within root tissues using nitro blue tetrazolium staining and an incident light optical system that permits detailed observations of intact roots. The assay is rapid and easy to perform, and reveals that respiratory activity in roots is not uniform in space and time. The results show that root hairs in particular may be regions of enhanced respiratory activity in some species or in certain developmental or physiological states. This fact has important implications for the role of root hairs in the overall respiratory budget of roots and the energetics of nutrient assimilation. The results suggest that root respiration studies should consider differential respiratory activities of root cell types within roots. 相似文献
74.
MB Connolly P Crits-Christoph A Demorest K Azarian L Muenz J Chittams 《Canadian Metallurgical Quarterly》1996,64(6):1213-1221
This investigation explored the nature of transference of interpersonal patterns in patients' psychotherapy narratives. The relation between interpersonal patterns with significant others in a patient's life and the pattern with the therapist early in treatment was examined. Cluster analysis was used to categorize similar relationships for each of 35 patients. Many patients revealed multiple interpersonal themes in their relationship narratives. Furthermore, these interpersonal themes correlated significantly with the interpersonal pattern extracted from narratives told about the therapist for many of the patients who discussed the therapeutic relationship during therapy. However, the interpersonal pattern evident in the relationship with the therapist was not necessarily the most pervasive pattern exhibited in the narratives about significant others. 相似文献
75.
Comments on D. M. Buss' (see record 1995-21138-001) comment on A. H. Eagly's (see record 1995-21141-001) discussion comparing the sexes in scientific research. The author disputes Buss' use of particular assumptions as facts and his concepts of culture, social behavior, and sexual selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
If video cameras could be used to measure colours directly, many technical and commercial possibilities would opened up. Christine Connolly, William Leung and Jim Nobbs describe how this is now close to being a reality. 相似文献
77.
The applications of information technology in health care are now widespread and continue to grow. Medical imaging is at the forefront of this revolution and the introduction of digital detection methods to replace film is now addressing the diagnostic X-ray market, the most routinely employed imaging modality. The introduction of picture archiving and communication systems, hospital and radiology information systems is well underway, and the integration of radiation protection initiatives into these developments is desirable. In north-west UK, a project aimed at developing and implementing IT-driven radiation protection strategies has been underway for the past 10 y. Such strategies are geared towards the support of European Commission patient dose directive 97/43 EURATOM, in particular the need to implement clinical audit, patient dose audit and to establish dose reference levels. This paper demonstrates the national and local requirements for establishing a central dose data management system for use in radiation protection strategies. In particular, such a system can help develop and support the role of a medical physics expert in optimisation. The scientific requirements for such an approach are presented in this paper, and a prototype system is described. Preliminary results obtained with the central data management facility are also presented and the implication for analysing multiple site dose data in optimisation strategies for digital radiographic technology is highlighted. 相似文献
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79.
The fatty acid composition of ceramides has been determined in kidney and cerebellum of a patient with Farber's disease, which
is characterized by ceramidase deficiency. Farber cerebellum and kidney contained a five- and ten-fold excess, respectively,
of free ceramides. The nonhydroxy fatty acid patterns of the ceramides from Farber kidney and cerebellum showed considerable
similarities to those from control tissues, whereas large amounts of ceramides containing hydroxy fatty acids are found in
Farber's disease tissues. 相似文献
80.
T Muldoon K Milligan P Quinn DC Connolly K Nilsson 《Canadian Metallurgical Quarterly》1998,80(5):680-681
We have compared the analgesia and motor block produced by extradural infusions of ropivacaine and bupivacaine after total knee arthroplasty. Fifty-two patients received 8 ml h1 of either 0.2% ropivacaine or 0.2% bupivacaine by extradural infusion for 24 h after operation. Analgesia was assessed by postoperative visual analogue scale (VAS) and morphine consumption. At rest these were low in both groups; median VAS was 0-13.3 mm for the ropivacaine group and 0-0.5 mm for the bupivacaine group. Over the 24 h of the infusion, the estimated (ropivacaine bupivacaine) difference in wound pain at rest was 5.6 mm (P = 0.017) and on passive movement 11.6 mm (P = 0.016). Median morphine consumption was 30.7 mg in the ropivacaine group and 20.5 mg in the bupivacaine group. In the ropivacaine group, 50% of patients compared with 19% in the bupivacaine group had no motor block 2 h after operation, increasing to 88% for ropivacaine and 56% for bupivacaine by 24 h. Bupivacaine produced significantly more frequent and intense motor block over the 24 h (P = 0.015). 相似文献