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51.
杨娅 Thomas Bartel Loredana Latina Guido Caspari 王新房 Raimund Erbel 《华中科技大学学报(医学英德文版)》2002,22(2):158-163
Coronary flow reserve (CFR) has been used toassess coronary microcirculation and epicardial coro-nary stenoses[1— 3 ] . CFR is defined as the ratio ofcoronary flow under maximal coronary vasodilatationto coronary flow under resting conditions[4 ] .Whenthe cross- sectional area of epicardial coronary arteriesis constant,coronary flow velocity (CFV) ratios areequal to volume flow ratios.The most common method used clinically formeasuring CFVR is intracoronary Doppler flow(ICD) analysis re… 相似文献
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Carlo Bertucci Enrico Domenici Piero Salvadori 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):843-846
The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized. 相似文献
55.
Carlo La Vecchia Silvia Franceschi Ettore Bidoli Fabio Barbone Piero Dolara 《International journal of cancer. Journal international du cancer》1993,55(3):386-389
The relationship between sugar added to coffee and other hot beverages--as an indicator of taste for sugar and sugar intake outside main meals--and the risk of colorectal cancer was investigated using data from a case-control study conducted in Northern Italy on 953 cases of histologically confirmed colon cancer, 633 of rectal cancer and 2845 controls admitted to hospital for acute, non-neoplastic, non-digestive tract disorders. Compared with subjects who reported adding no sugar to their beverages, the multivariate relative risks (RR) of colon cancer were 1.4 for those adding one spoonful of sugar, 1.6 for those adding 2 spoonsful, and 2.0 for those adding 3 or more. The corresponding RRs for rectal cancer were 1.3, 1.5 and 1.4. For combination of colorectal cancer the RRs were 1.4, 1.5 and 1.8. All the trends in risk were significant, and the results were consistent across strata of study centre, sex and age, and were not appreciably modified by allowance for a number of major identified potential distorting factors, including an estimate of total calorie intake. These findings, if confirmed, would suggest that taste for sugar is a relevant indicator of colorectal cancer risk, and could be interpreted either in terms of a role of sugar in colorectal carcinogens, or of a specific influence of even limited amounts of sugar taken outside meals, which may stimulate the proliferation of the bowel epithelium, and hence enhance colorectal carcinogenesis. 相似文献
56.
Irwin L. Flink 《Brain structure & function》2002,205(3):235-244
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