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S J Graafsma L J van Tits P van Heijst J Reyenga J F Rodrigues de Miranda T Thien 《Journal of cardiovascular pharmacology》1989,14(4):598-602
The effect of handgrip (HG) isometric exercise on plasma catecholamines, alpha 2-adrenoceptors on platelets and beta 2-adrenoceptors on lymphocytes was studied in normotensive subjects (NT) and essential hypertensive subjects (HT). Whereas systolic blood pressure (SBP) increases were similar in NT and HT subjects, diastolic blood pressure (DBP) and heart rate (HR) increased more in the former group. Baseline values and changes in plasma epinephrine (E) and norepinephrine (NE) did not differ between both groups. No differences were apparent in alpha 2-adrenoceptor density and affinity between NT and HT subjects before or after the test. HG isometric exercise induced a similar increase in beta 2-adrenoceptors on lymphocytes of 22 +/- 7 and 13 +/- 5% in NT and HT subjects, respectively. Affinity to the beta 2-adrenoceptors under baseline conditions was somewhat lower in HT (8.1 +/- 0.4 pM) than in NT subjects (6.5 +/- 0.5 pM), and this difference persisted during the test. Our results indicate that there are no differences in alpha 2- and beta 2-adrenoceptor densities either at baseline conditions or after HG isometric exercise between NT and HT subjects. Small differences noted in affinity to the beta 2-adrenoceptors require further investigation. 相似文献
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P M A van Haaren H P Kok C A T van den Berg P J Zum V?rde Sive V?rding S Oldenborg L J A Stalpers M S Schilthuis A A C de Leeuw J Crezee 《International journal of hyperthermia》2007,23(3):303-314
PURPOSE: The aim of this study was to verify hyperthermia treatment planning calculations by means of measurements performed during hyperthermia treatments. The calculated specific absorption rate (SAR(calc)) was compared with clinically measured SAR values, during 11 treatments in seven cervical carcinoma patients. METHODS: Hyperthermia treatments were performed using the 70 MHz AMC-4 waveguide system. Temperatures were measured using multisensor thermocouple probes. One invasive thermometry catheter in the cervical tumour and two non-invasive catheters in the vagina were used. For optimal tissue contact and fixation of the catheters, a gynaecological tampon was inserted, moisturized with distilled water (4 treatments), or saline (6 treatments) for better thermal contact. During one treatment no tampon was used. At the start of treatment the temperature rise (DeltaT(meas)) after a short power pulse was measured, which is proportional to SAR(meas). The SAR(calc) along the catheter tracks was extracted from the calculated SAR distribution and compared with the DeltaT(meas)-profiles. RESULTS: The correlation between DeltaT(meas) and SAR(calc) was on average R = 0.56 +/- 0.28, but appeared highly dependent on the wetness of the tampon (preferably with saline) and the tissue contact of the catheters. Correlations were strong (R approximately 0.85-0.93) when thermal contact was good, but much weaker (R approximately 0.14-0.48) for cases with poor thermal contact. CONCLUSION: Good correlations between measurements and calculations were found when tissue contact of the catheters was good. The main difficulties for accurate verification were of clinical nature, arising from improper use of the gynaecological tampon. Poor thermal contact between thermocouples and tissue caused measurement artefacts that were difficult to correlate with calculations. 相似文献
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Williamson Kathleen A.; Hever Ann M.; Rainger Joe; Rogers R. Curtis; Magee Alex; Fiedler Zdenek; Keng Wee Teik; Sharkey Freddie H.; McGill Niolette; Hill Clare J.; Schneider Adele; Messina Mario; Turnpenny Peter D.; Fantes Judy A.; van Heyningen Veronica; FitzPatrick David R. 《Human molecular genetics》2006,15(12):2030
Table 1 相似文献
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Marieke Peeters Ludo Verhoeven Jan de Moor Hans van Balkom 《Research in developmental disabilities》2009,30(4):712-726
The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness, Phonological Short-term Memory (STM), Speech Perception, Speech Production and Nonverbal Reasoning were considered reading precursors. Children with cerebral palsy lag behind on all reading precursors at the beginning of the second year of kindergarten. For the children without disabilities, early reading skills in Grade 1 were best predicted by Phonological Awareness and Phonological STM while Speech Production was the most important predictor of early reading success for the children with cerebral palsy, followed by Phonological Awareness and Speech Perception. Furthermore, for children with cerebral palsy, Speech Production appears to dominate reading development, as Speech Production measured at the beginning of the second year of kindergarten was strongly predictive of all other reading precursors measured at the end of the second year of kindergarten. The results of this study reveal that children with cerebral palsy with additional speech impairments are at risk for limited literacy development. Clinical implications are discussed. 相似文献
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