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1.
Faidon Magkos Yannis Manios Eirini Babaroutsi Labros S. Sidossis 《Osteoporosis international》2006,17(2):304-312
The aim of this study was to develop and evaluate a food frequency questionnaire (FFQ) for assessing dietary calcium intake in the general population, since all available questionnaires at present are age- and/or gender-specific. A total of 1001 individuals (including children, adults, and elderly people of both genders) were randomly recruited throughout Greece. Estimates of calcium intake from the 30-item FFQ were compared with those from a multi-pass 24-h recall. The FFQ underestimated mean calcium intake compared to the 24-h recall by (mean±SD) –133±333 mg/day or –5.4±47.6% (P<0.001). The two methods were strongly correlated (r=0.639, P<0.001), but the 95% limits of agreement for individual assessment were rather wide, as the FFQ could provide estimates of calcium intake from 533 mg/day above to 799 mg/day below the 24-h recall. Actual values for surrogate FFQ quartiles manifested a progressive increase, with significant differences between mean calcium intakes (P<0.001). The FFQ could identify individuals who consumed less calcium than 800 mg/day or less than the age-specific adequate intake with a relatively high sensitivity (82.8 and 95.5%, respectively), but low specificity (54.9 and 34.1%, respectively). Cross-classification analysis indicated that only 17 subjects (1.7%) were grossly misclassified (lowest quartile for one method and highest quartile for the other), while 827 subjects (82.6%) were correctly classified (into the same or adjacent quartiles). The FFQ could be used in population-based epidemiological studies or screening programs involving individuals of all ages and both genders, where the discrimination of subjects with relatively low (<500 mg/day) and relatively high (>1000 mg/day) calcium intakes is of primary interest. Results, however, do not support its use for the quantitative assessment of individual calcium intakes. 相似文献
2.
Animal behaviour can be viewed as a stream of elements, which, once accurately described, can be counted and timed. Data acquisition techniques and tools are reviewed, and some strategies for collection and analysis of data using PC computers are suggested. Automated instruments are not satisfactory for the study of complex behaviour and as such systemic observation remains irreplaceable. IBM PC-type computers, with a wide range of analytical software (e.g., spreadsheets, statistical packages, technical graphics), are practical for data acquisition. Several systems which can satisfy different applications are reviewed. Some systems can communicate with a videorecorder, a facility which remarkably increases the accuracy of measurement; this is essential for meaningful analyses of the internal structure of behavioural streams (sequences, time patterns) or communication processes. The power of new tools enables behavioural measurement with the necessary complexity to allow a whole new set of questions to be addressed. However, it also increases demands for meaningful content and analysis of data. 相似文献
3.
目的 评价和探讨修复骨外露及皮肤软组织缺损的各种方法 ,使其更好地用于临床。方法 3 5例不同部位的骨外露分别采用皮片移植、皮瓣及肌皮瓣转移、皮瓣及肌皮瓣游离移植等方法 ,覆盖外露的骨面。结果 3 1例全部存活 ,1例皮瓣部分坏死 ,2例创口延迟愈合 ,1例游离皮瓣失败。结论 对骨外露及皮肤软组织缺损应尽量在早期修复 ,最常用的方法是皮瓣及肌皮瓣的转移或移植。 相似文献
4.
以钒基核苷酸复合物为核酸酶抑制剂,从人胚组织中制备总RNA,所得产品几乎不含DNA和蛋白质,经过分离Poly(A)~ mRNA,证明制品有合成cDNA的完整功能,方法比较简捷,适于大量制备以满足分离mRNA 之需,并讨论了此法的优缺点。 相似文献
5.
17β-雌二醇对子宫内膜异位症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响 总被引:2,自引:0,他引:2
目的研究17β-雌二醇(17β-E2)对子宫内膜异位症(内异症)患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响,探讨Wnt/β-catenin信号通路在介导雌激素促进内异症发生发展的作用。方法体外分离培养内异症患者在位子宫内膜间质细胞。用不同浓度17β-E2处理子宫内膜间质细胞48 h;此后选用10-10mol/L 17β-E2处理子宫内膜间质细胞12、24和48 h,逆转录聚合酶链反应(RT-PCR)和免疫印迹法(Western blotting)检测17β-E2处理前后子宫内膜间质细胞β-catenin mRNA和蛋白的表达水平。同法分析雌激素受体拮抗剂ICI182,780(10-6mol/L)对17β-E2促进β-catenin mRNA和蛋白表达的影响。免疫组织化学染色观察17β-E2作用后β-catenin在子宫内膜间质细胞中的定位。结果17β-E2能明显促进内异症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白的表达,并呈剂量和时间依赖性,于10-10mol/L作用48 h最明显。雌激素受体拮抗剂ICI182,780能明显抑制17β-E2对子宫内膜间质细胞β-catenin mRNA和蛋白的表达。免疫组织化学染色发现17β-E2能促进β-catenin在子宫内膜间质细胞核内的表达。结论雌激素可能通过激活Wnt/β-catenin信号通路促进内异症在位子宫内膜的异位种植。 相似文献
6.
目的:探讨异丙酚连续硬膜外麻醉时辅助用药的方法及其药代动力学特性。方法:30例下腹部或下肢手术病人随机分为两组,在连续硬膜外麻醉下分别以不同速度静滴异丙酚,同时高压液相法测定血药浓度。结果:以10→8→5mg/(kg·h)方法给药,患者意识消失明显快于5mg/(kg·h)恒速给药组(P<0.05)。平均意识消失及苏醒血药浓度分别为(2.1±0.7)mg/L及(1.0±0.5)mg/L。结论:连续硬膜外麻醉时辅助用药以10→8→5mg/(kg·h)的给药方法为佳。为避免术中病人觉醒,最低给药速度不得低于5mg/(kg·h)。 相似文献
7.
腹腔镜胃切除治疗胃间质瘤26例临床报告 总被引:1,自引:0,他引:1
目的:探讨腹腔镜胃切除术治疗胃间质瘤的安全性及可行性。方法:2003年8月至2007年9月间,26例胃间质瘤病人在腹腔镜下行胃部分切除手术,其中17例行胃楔形切除、6例近端胃切除、3例远端胃切除。结果:无中转开腹,无手术死亡。手术平均出血量15(10~75)ml,平均手术时间(144±74)min,平均切口长度(5.5±1.5)cm,平均术后住院日为(8.3±3.6)d。手术并发症发生率7.69%(2/26),其中1例肺感染、1例切口感染。病理结果:极低度风险8例、低度风险12例、中度风险4例、高度风险2例。随访3~48个月,2例病人出现肝转移、现带瘤生存,其余无瘤生存,目前总生存率100%,复发率7.69%(2/26),3年无瘤生存率96.0%。结论:腹腔镜下胃切除术治疗胃间质瘤是安全、可行的,手术近期疗效令人满意,远期结果有待进一步观察。 相似文献
8.
Fahlman A Jackson S Terblanche J Fisher JA Vesely A Sasano H Myburgh KH 《Respiratory physiology & neurobiology》2002,133(3):185-270
We report the development and testing of a simple breathing circuit that maintains isocapnia in human subjects during hypoxic hyperpnea. In addition, the circuit permits rapid switching between two gas mixtures with different partial pressures of oxygen. Eleven volunteers breathed repeated cycles of exposure to air (2 min of 21% O(2), balance N(2)) and hypoxia (2 min of 8.3+/-0.1% O(2), balance N(2)). Hypoxia induced significant increases in minute ventilation, breathing frequency and tidal volume (P < 0.05) that were consistent over repeated cycles of hypoxia (P > 0.1, one-way ANOVA). The system successfully maintained isocapnia in all subjects, with an average change in end-tidal CO(2) of only -0.2 mmHg during hyperventilation in hypoxia (range 0.4 to -0.8 mmHg). This system may be suitable for repeated tests of the hypoxic ventilatory response (HVR) and may prove useful for exploring intra- and inter-individual variability of HVR in humans. 相似文献
9.
A. A. H. P. Megens J. Voeten J. Rombouts T. F. Meert C. J. E. Niemegeers 《Psychopharmacology》1987,93(3):382-388
Spontaneous and drug-induced (haloperidol, apomorphine, and amphetamine) motor activity of rats was measured simultaneously via two distinct and independent methods: the classical optical scanning technique and a new procedure based on the piezo-electric principle. The latter procedure measured animal-induced mechanical vibrations of a flexible cage floor which were transduced into electric signals via piezo-electricity. The piezo method appeared to be relatively more sensitive in recording the small, stereotyped motor movements induced by apomorpine (0.63–10 mg/kg) and high doses of amphetamine (2.5–20 mg/kg). The optical scanning technique, on the other hand, was more sensitive in recording horizontal displacements across the cage such as induced by low doses of amphetamine (0.31–2.5 mg/kg). Both methods showed comparable sensitivity in recording the depression of behaviour induced by haloperidol (0.04–1.25 mg/kg) or low doses of apomorphine (0.04–0.16 mg/kg). The piezo method may complement the optical scanning procedure, and thereby enhance the information on the extent that test compounds modify animal behaviour. 相似文献
10.
周明华谭红何思长罗鑫 《中国卫生质量管理》2022,(8):033-36
目的分析四川省内中医医院医疗费用结构变动情况,为促进中医医院医疗费用精细化管理提供依据。方法采用描述性分析法和结构变动度方法对四川省内中医医院2014年-2019年门诊和住院医疗费用结构变动情况进行分析。结果门诊收入中,中药收入平均占比最高(31.46%),手术收入平均占比最低(1.32%);检查收入在2016年-2019年、中药收入和其他收入在2018年-2019年为负向变动;治疗收入贡献率呈先上升后下降特点,手术收入的贡献率和拉动力处于最小状态。住院收入中,其他收入平均占比最高(34.88%),手术收入平均占比最低(5.41%);检查收入从2016年起、治疗收入从2017年起、手术收入从2018年起为正向变动;中药收入贡献率和拉动力不断增强,手术收入的拉动力在2019年明显提升。结论住院中药收入占比较低,应拓展中医药服务项目;治疗收入和手术收入结构变动贡献率较小,要加强中医医院服务能力建设;检查收入和其他收入拉动力较大,要加强对医务人员医疗行为的监管。 相似文献