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41.
42.
Objective: To analyze quantitatively the synergistic and antagonistic effects of combined oxymatrine (OMT) and 5-fluorouracil (5-GU) on a cell line of human liver cancer (HepG2) with median-effect principle in vitro. Methods: The median-effect principle and MTT method were used in the quantitative analysis of effects of the two drugs. Results: Cytotoxic activity of the individual drugs enhanced as drug concentration increased. As fa=0.41, a CI equal to 1 indicated additivity; fa<0.41, a CI less than 1 indicated synergy; and fa>0.41, a CI greater than 1 indicated antagonism. The sequence of administration did not influence the cytotoxic activity of the combined antitumor drugs. The ratio of drug concentration was a factor that can influence the killing effect. Conclusion: The combined drugs interaction (CI<1) was synergistic at lower concentration and antagonistic at higher concentration. The ratio of drug concentration is a factor that can influence the killing effect. Biography: HE Song(1965–), male, doctor of medicine, associate professor, Chongqing Medical University, majors in gastroenterology.  相似文献   
43.
Abstract Changes in colonic motor activity during aerobic exercise were investigated in ten regularly exercising volunteers (five males and five females) aged 27–70 years. Motility was recorded with a catheter containing three solid-state pressure transducers spaced 5 cm apart. The motility catheter was advanced 40–50 cm from the anal verge by flexible sigmoidoscope without anesthesia at least 60 min prior to testing. Manometric recordings were made from the colon during a 1-h pre-exercise rest period, 1 h of jogging at 70–80% maximum heart rate, and 1-h post-exercise rest period. The dominant frequency of contractile activity in the colon shifted from 1–4 cpm during rest, to 4–9 cpm with the onset of exercise. Activity also shifted from sporadic, isolated contractions to regular, propagated contractions in six of ten subjects, five of whom reported a history of runner's diarrhoea. The dominant frequency returned to 1–4 cpm during the post-exercise period. These changes in distal colonie motility may account for the diarrhoea which some subjects experience during intense, acute exercise.  相似文献   
44.
反映手术间利用效率的统计指标与方法探讨   总被引:1,自引:0,他引:1  
目的 探索反映手术室工作状态的指标和方法,为了解科室需求、合理利用手术室资源奠定基础。方法 提取医院局域网中有关手术安排、手术过程、麻醉等信息,通过常用统计指标、统计图表,反映手术室、手术科室、手术间的工作状态。结果 工作日手术问日均工作6.34小时,节假日日均工作0.6l小时。工作日13点后有近l/3的空台,14点后近l/2空台。个别手术间利用率偏低。结论 1.由在用手术间时点统计结果可见,14点后接台手术尚有一定潜力,节假日安排手术潜力更大;2.工作日间均工作时数已近满负荷,若要进一步提高手术间的利用,需加强麻醉科和手术室力量。  相似文献   
45.
Attention to the different types of carbohydrates and their role in health and disease is relatively recent. FAO and WHO jointly published a report on carbohydrates in human nutrition in 1998, with a number of recommendations about increasing carbohydrate intake as a sound approach to the prevention of obesity. The glycemic index (GI) was recommended as a means of classifying foods on the basis of their potential for raising blood glucose; this concept was based on the understanding that the state of hyperglycemia that is observed following the intake of certain high-GI carbohydrate foods could constitute a risk factor for diseases of lifestyle.  相似文献   
46.
A representative sample of 1650 children randomly selected in the 6-15-yr-old schoolchild population of Strasbourg was examined by well-calibrated examiners. The prevalence of caries was determined with the DMFT, DMFS and dft indices using bitewing radiographs. Plaque, calculus and gingival indices were also determined. The results obtained were compared with the initial study of 1974 performed in Strasbourg using the same epidemiologic methods. Whereas no important variations were observed in caries prevalence of primary teeth, a significant reduction of caries activity was observed in DMFT and DMFS indices in all age groups. There was a reduction of these two indices of respectively 32% and 33% in the 12-yr-old children. The reduction was the most significant on approximal surface lesions. A statistically significant decrease of the calculus and gingival indices was also observed between 1974 and 1984. A less significant decrease was observed for the plaque index.  相似文献   
47.
防晒制剂皮肤安全性的实验研究   总被引:2,自引:0,他引:2  
目的 :探讨同一系列不同SPF(sunprotectionfactor)防晒制剂对皮肤的安全性 ,筛选安全有效的防晒制剂配方。方法 :选用白化豚鼠背部去毛 ,分别涂抹SPF值为 15、2 8、30 +三种防晒制剂 ,以UV光源照射 ,波长为 32 0~4 0 0nm ,强度为 ( 16 8± 2 )mW/cm2 。结果 :三种不同SPF防晒制品对实验动物皮肤各时相点反应积分为 ,SPF15组为0 ;SPF2 8组为 1;SPF30 +组为 3。结论 :三种不同SPF值产品对皮肤的光毒性有一定差异 ,提示SPF值在 2 8以内的防晒制剂皮肤安全性较好 ,SPF30 +的防晒制剂对皮肤有一定光毒刺激反应。  相似文献   
48.
In children with acute obstructive lung disease gas exchange is affected by ventilation-perfusion mismatch and the degree of bronchoconstriction. Standard lung function measurements do not reflect the impairment in gas exchange. Alternatively, the effective pulmonary blood flow (EPBF), that is, the proportion of the cardiac output that is supplying well-ventilated lung units, can give accurate and noninvasive estimates of ventilation-perfusion mismatch. We measured EPBF with the argon freon ?22 rebreathing technique in children with acute severe asthma to assess their response to nebulized salbutamol and to determine whether induced changes in the EPBF could be predicted from baseline measurements. Twenty-four children admitted with an acute asthma attack had spirometry and triplicate EPBF measurements before and after nebulized salbutamol. Eighteen patients had repeated tests 50 days later when fully recovered; 4 patients were taking methylxanthines on at least one occasion. The mean forced expiratory volume in 1 sec (FEV1) rose from 55% of predicted to 66% after salbutamol and to 83% with recovery. The mean coefficients of variation for EPBF measurements on the three test occasions were 11.3%, 8.2%, and 9%. Except in children on methylxanthines, the EPBF values were reduced during the acute asthma attack (median, 2.53 L/min/m2; range, 1.99–3.60 L/min/m2) compared with paired values obtained after recovery (median, 2.89 L/min/m2; range, 2.2Eb4.04 L/min/m2) (P = 0.009). Salbutamol caused a highly significant increase in EPBF from 2.88 L/min/m2 (range, 1.86–3.80) before treatment to 3.34 L/min/m2 (range, 2.264.65) immediately afterwards (P = 0.0003). The spirometric indices did not relate to the changes in the EPBF values. However, when the effective stroke volume index was calculated in 11 patients, the changes induced by nebulized salbutamol had a significant inverse relation with the pretreatment FEV, (P = 0.61; P = 0.02). In conclusion, the argon freon-22 rebreathing technique can be used successfully and reproducibly to measure EPBF in children with an acute asthma attack. Except in children taking methylxanthines, EPBF during the acute attack is reduced and rises significantly after salbutamol. EPBF values after recovery were significantly higher than the presalbutamol values during the attack. Spirometric indices do not relate to the EPBF changes but are inversely related to the effective stroke volume changes. Pediatr Pulmonol. 1994; 17:370–377. © 1994 Wiley-Liss, Inc.  相似文献   
49.
对广西武鸣华侨农场4158人进行基线普查,410人进行膳食调查和作8小时夜尿电解质测定,并将高血压低发区广西的资料与高发区的北京作对比.结果显示,体重指数高是高血压一个重要的危险因素,而体重过重又与膳食中摄入碳水化合物和总热量大有关.另一主要的危险因素是钠,膳食中摄入钠高,尿Na和Na/K比值高者,血压水平和高血压的患病率亦高.  相似文献   
50.
OBJECTIVE: The purpose of this study was to evaluate a relationship between the umbilical cord thickness and cord coiling patterns during the fetal sonographic anatomic survey in the second trimester of pregnancy. METHODS: This was a prospective study of 470 patients with singleton pregnancies who had a fetal anatomic survey with recorded umbilical coiling patterns between 18 and 23 weeks' gestation. The umbilical cord thickness was assessed as an umbilical diameter at the level of the fetal abdominal cord insertion and compared with the antenatal umbilical coiling index (aUCI), calculated as a reciprocal value of the distance between a pair of umbilical cord coils. RESULTS: Three hundred twenty-one patients had adequate sonographic umbilical cord images and maternal demographic, antenatal, and labor data to meet inclusion criteria. The mean aUCI was 0.41 with 10th and 90th percentiles of 0.21 and 0.60, respectively. A total of 10.6% (34/321) and 9.3% (30/321) of patients were categorized as having hypocoiled and hypercoiled umbilical cords, respectively. The mean cord diameter +/- SD was 9.48 +/- 0.97 mm (range 7.0-12.5 mm). There was no statistically significant correlation between aUCI and umbilical cord thickness (P = .1164). CONCLUSIONS: An aUCI, or umbilical coiling pattern, does not correlate with umbilical cord thickness. It appears that a lesser amount of the umbilical supportive tissue, mainly Wharton jelly, is not related to an increased umbilical cord coiling pattern.  相似文献   
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