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Meta-analysis: a review of pros and cons 总被引:8,自引:0,他引:8
J H Abramson 《Public health reviews》1990,18(1):1-47
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Our previous work on a social insect model of ethanol-induced behavior focused on behavioral studies of honeybees (Apis mellifera L.). We now investigate the dependence of honeybee blood ethanol concentration on both the amount of ethanol consumed and time elapsed since ingestion. Blood ethanol level was determined using gas chromatograph using hemolymph taken from harnessed bees. Significantly increased levels of ethanol in honeybee hemolymph were detected within 15 min of feeding bees alcohol. Within 30 min, ethanol concentration increased 2.7 times. The concentration of ethanol ingested also had a significant effect on blood ethanol level. However, postfeeding times greater than 30 min did not significantly increase ethanol concentration in bee hemolymph. This study integrates with our behavioral data on the effect of ethanol on honeybees. Our laboratory and field experiments show a correlation between the time frame for behavioral changes and significant increases of blood ethanol levels shown in this study. 相似文献
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B. Falk Y. Weinstein R. Dotan D. A. Abramson D. Mann-Segal J. R. Hoffman 《Scandinavian journal of medicine & science in sports》1996,6(5):259-264
Anaerobic power is characterized by a high degree of specificity regarding both the recruited muscles as well as the recruitment pattern. The popular Wingate Anaerobic Test (WAnT) is a cycling test that does not satisfy the need for a running-specific anaerobic test. We describe such a test, using a novel type of a commercially available treadmill (BRL 1800, Gymrol, France). The ergometer is equipped with a torque motor to neutralize the frictional resistance of the treadmill belt, and a hip-belt harness connected to a horizontal rod. Force applied to the harness is monitored by a strain gauge mounted on the rod, while vertical movement is monitored by a potentiometer at the posterior fixed end of the rod. These, in conjunction with the treadmill belt speed, enable the computation of horizontal and vertical power as well as the combined total output. Power is calculated both as 'peak' power (highest 2.5 s segment) and 'mean' power (20 s duration). Preliminary results of young athletes were generally consistent with the expected age-related changes in anaerobic power. Values obtained on the anaerobic treadmill were always higher than the corresponding WAnT values previously obtained in comparable age groups. The higher values were probably due to the larger muscle mass involved and the shorter peak and mean power durations (2.5 and 20 s versus 5 and 30 s in the WAnT, respectively). This test should enable not only running-specific anaerobic power monitoring but also the characterization of the relationship between the horizontal and vertical components of that power. 相似文献
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D H Abramson C A Servodidio B McCormick D Fass E Zang 《The British journal of ophthalmology》1990,74(6):359-362
Serial ultrasonic measurements of 82 uveal melanomas treated with brachytherapy plaques (cobalt-60 and iodine-125) and followed up for up to 141 months revealed that no two patients had identical patterns of change. The mean absolute change in tumour height after treatment was 1.8 mm at six months, 5.6 mm at 48 months for large tumours, and 0.9 and 1.9 mm for medium sized tumours. Eighty of the 82 patients fell into one of three patterns of response: 57 patients had a decrease in height after treatment (type D), 13 patients had the same height after treatment (type S), and 10 patients had a progressive increase in height (type I). Life table comparison showed no correlation between survival and location of tumour, sex of patient, size of tumour when treated, or laterality. There was a slight correlation between age and survival. Patients older than 60 died more frequently from metastatic melanoma than those under 60 (p = 0.06). Life table analysis showed a significant correlation between tumour regression type and survival. At 48 months the best cumulative probability of survival was in patients with type D (88% alive) compared with those of type I (34% alive, p = 0.0004). 相似文献
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Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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