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51.
ADEL ISSA SOUSSOU MOHAMED GAMAL HELMY RAMEZ RAOUF GUINDY ENRICO MARIA GRECO 《Pacing and clinical electrophysiology : PACE》1992,15(11):1804-1808
The pocing rate response of a new acceleration driven pulse generator (SWING 100, SORIN BIOMEDICA) was compared with simultaneous normal sinus rhythm (NSR) during two different treadmill exercises. This pacemaker has a gravitational acceleration sensor able to discriminate between physical activities and vibrations. Six healthy volunteers (three male, three female; aged 21.7 ± 4,3 years), with the pacemaker strapped to their right infraclavicular area, performed each test three times with different rise response curve (RRC) each time: fast, normal, and slow. The fall response curve used was the same as the rising one during each test. Pacing rates were recorded using the VEGA analyzer (SORIN BIOMEDICA) and compared with simultaneous NSR recorded by a 7-channel ECG recorder (MINGOGRAF 7, SIEMENS), During all tests immediate (within seconds) rapid increase in pacemaker rate was seen up to about 60 seconds, then a slower increase followed thereafter. The mean correlation between pacing rates and NSR during the Bruce tests were 0.7941 ± 0.10, 0.8562 ± 0.14, and 0.8292 ± 0.07; during the discontinous tests 0.7292 ± 0.16, 0.7233 ± 0.10, and 0.7480 ± 0.11 for fast, normal, and slow RRC, respectively. Each 30 seconds, nonsignificant differences were present between pacing rate and NSR during all the discontinuous tests; similar responses were observed only during the first two stages of Bruce tests after which NSR was significantly higher than pacemaker rates. The speed of rise to upper rate was the main difference between the different programs (fast, normal, and slow). The discontinuous tests showed that the pacemaker responds more to speed than to grade. In conclusion, the Swing pacemaker is easy to use and program, fast, reliable, and is able to mimic the normal sinus behavior especially during discontinuous activities. 相似文献
52.
53.
Tamaki Sasaki Tetsuya Sato Yoshiyuki Jyo Nobuya Tanda Hitoshi Tamai Gengo Osawa 《Clinical and experimental nephrology》1997,1(1):32-40
Background We previously found that glomerular epithelial cells play an important role in the formation of adhesive lesions. Glomerular
sclerotic lesions develop after the inital adhesive lesions.
Methods Two series of experiments were done with spontaneously diabetic WBN/Kob rats. These rats develop segmental glomerular sclerotic
lesions with aging. The first series of experiments was intended to clarify the kinetics of glomerular cells on progressive
glomerular damage in these rats. The second series of experiments was designed to study the relationship between proliferation
(judged by % bromodeoxyuridine-positive cells) of glomerlar epithelial cells and sclerotic lesions with adhesions.
Results In the first series, rats having increased proteinuria showed segmental glomerular sclerotic lesions with adhesions. At the
same time, increased labeling indices of tuft cells and epithelial cells of Bowman's capsule were observed. In the second
series, no significant increase in the labeling indices of tuft cells with sclerotic lesions was observed, compared to tuft
cells without sclerotic lesions. In sclerotic lesions with adhesion, bromodeoxyurdine-positive cells were observed that were
not distinguishable as podocytes or epithelial cells of Bowman's capsule. The highest labelling index was noted in the epithelial
cells of Bowman's capsules with sclerosis.
Conclusion This study shows that the proliferation of glomerular epithelial cells (mainly epithelial cells of Bowman's capsule) occurs
in glomerular sclerotic lesions with adhesions. 相似文献
54.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义 总被引:1,自引:1,他引:0
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。 相似文献
55.
56.
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
57.
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
58.
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
59.
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
60.
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