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101.
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
102.
William M. Chadduck H. Mark Crabtree James B. Blankenship James Adametz 《Child's nervous system》1991,7(1):27-30
Previous studies have demonstrated a high correlation between hydrocephalus and the resistive index (RI), as determined by transcranial Doppler ultrasonography. Measurements of RI, calculated by dividing the difference between the peak systolic velocity and the enddiastolic velocity by the peak systolic velocity, were attempted in 55 pediatric patients during evaluations for ventriculoperitoneal shunt malfunctions; values were obtained in 52. Indications of shunt malfunction included both clinical and radiographic evidence of increased intracranial pressure. Eleven patients, determined to have functional shunts both by clincal criteria and subsequent outcome, had RIs of 47±5 (average±1 standard deviation). Shunt malfunctions were confirmed in 41 patients. Prior to shunt revisions, these 41 patients has RIs of 71±10%; following revision, the RIs fell to 53±12%. Nine patients had had pre-malfunction RIs of 48±11% obtained during routine follow-ups; when they subsequently had shunt malfunctions, their RIs had significantly increased. Four of the 41 patients with shunt malfunctions had essentially normal RIs (52±7%), but had fluid tracking along the shunt; in these, RIs were essentially unaffected by shunt revision. For comparison, 119 pediatric patients with clinically functional ventriculoperitoneal shunts had RIs of 50±9%. The data, statistically significant with a P value of <0.001, showed a correlation between elevated RIs and shunt malfunction; thus, transcranial Doppler ultrasonography is a practical, non-invasive technique useful in the diagnosis of ventriculoperitoneal shunt malfunction.Presented at the Annual Meeting of the Pediatric Section of the American Association of Neurological Surgeons, Washington D.C., November 1989 相似文献
103.
广西壮、汉族体重指数与血压、血脂、脂肪肝等相关因素的关系 总被引:4,自引:0,他引:4
目的:探讨广西地区人群体重指数(BMI)与血压、血糖、血脂、脂肪肝、心电图异常、性别、民族及其他心脑血管病史等因素的相关性,并比较这些因素在壮族与汉族人群中的差异。方法:对在本院及田阳县、田东县参加体检的1105例壮族与汉族人群询问病史并检查身高、体重、血压、空腹血糖、血脂、肝脏B超、心电图等。结果:在按制其他因素后,汉族人群BMI与脂肪肝、舒张压水平及高血压病史呈密切正相关关系,男性BMI高于女性;壮族人群BMI与脂肪肝、血清甘油三酯浓度及收缩压水平有密切正相关关系,汉族人群的年龄、BMI、血清甘油三酯浓度、胆固醇浓度、收缩压水平、脂肪肝检出率及心电图异常检出率均较壮族人群高。结论:肥胖与脂肪肝、血压、血脂密切相关,且广西汉族人群肥胖、脂肪肝、高血脂、高血压及心电图异常较壮族人群更常见。 相似文献
104.
L. J. CHESKIN M. D. CROWELL N. KAMAL B. ROSEN M. M. SCHUSTER W. E. WHITEHEAD 《Neurogastroenterology and motility》1992,4(3):173-177
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
105.
目的探索如何提高新福林滴眼液的治疗指数。方法我们用10%-40μl、10%-10μl、2.5%-40μl、2.5%-10μl4组新福林滴眼液给16名健康大学生分次进行扩瞳试验,观察它们的扩瞳效果及用药后心率、血压的变化。结果同一容量10%比2.5%新福林扩瞳效果强。同一浓度10μl与40μl新福林扩瞳效果相似。10%-10μl与2.5%-40μl其新福林含量相等,但前者扩瞳效果要优于后者。4组新福林眼液对实验对象的心率和血压均无显著影响。结论采用高浓度小滴量新福林眼液扩瞳,不仅可以减少滴眼液的用量,提高其生物可用度,更重要的是可使其治疗指数得以显著提高。 相似文献
106.
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
107.
Guy Nantel PhD 《Nutrition reviews》2003,61(S5):s34-s39
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
108.
Pierre-Michel Cahen Jean-Christophe Turlot Robert M. Frank Gérard Clement Gil Seckler 《Community dentistry and oral epidemiology》1987,15(4):211-215
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
109.
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
110.
CHAIYASIT MATCHARIYAKUL WACHIRA KOCHAKARN SUCHART CHAIMUANGRAJ CHAREON LEENANUPUNTH PANUWAT LERTSITHICHAI 《International journal of urology》2004,11(5):310-315
BACKGROUND: The aim of the present study was to create a simple numerical index predicting the presence of prostate cancer in a group of high risk patients, for the purpose of selecting those most likely to need prostate biopsy. METHODS: 100 consecutive patients at high risk of having prostate cancer seen at Ramathibodi Hospital, Thailand between November 2000 and February 2002 were prospectively studied. All patients underwent transrectal prostate biopsies. The following predictor variables were obtained: age, digital rectal examination (DRE) findings, prostate specific antigen level, transrectal ultrasonography (TRUS) findings, and prostate volume determined by TRUS. The outcome was the presence of prostate cancer on histological examination of the biopsy specimens. A risk index for prostate cancer based on the linear predictor of a multiple logistic regression model was created. RESULTS: Almost all predictor variables were significantly related to the presence of prostate cancer. The final multiple logistic regression model with four categorized predictors (excluding DRE) was shown to have good discrimination, calibration, and cross-validity. For a cutoff risk index of 10, corresponding to a 10% probability of having prostate cancer, the sensitivity for detecting prostate cancer was 96.2%, with a specificity of 73.0%. Based on this cutoff, 55% of patients in this series might not require prostate biopsy. CONCLUSION: A risk index for prostate cancer was developed. If this index can be externally validated, the potential savings from avoiding unnecessary prostate biopsies, on the basis of selection using the index, could be significant. 相似文献