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101.
Summary With the use of duplex Doppler ultrasound and color Doppler flow imaging(CDFI), the characteristics of blood supply in neoplasma
were studied in 51 cases of 60 liver tumors, and compared with the results of surgery, pathological examination and hepatic
anerial angiography. The result showed that: 1. Doppler blood flow signals could be detected in all hepatic carcinomas, and
in 10 cases of 18 hemangiomas, significant difference was observed (P<0.001); 2. Doppler blood flow spectra showed pulsatile pattern in 41 of 42 hepatic carcinomas, and in 6 of 10 hemangiomas
(P<0.01); and 3. the peak flow velocity was obviously lower in hemangioma group than in hepatic carcinoma group (20.34±23.93
vs 64.74±30.18 cm,P<0.001). The characteristics of CDFI show that hemangiomas and hepatocellular carcinomas are different. It can, therefore,
be concluded that the blood supply of hepatic carcinomas mainly comes from hepatic arterial system, and is of value in duplex
Doppler ultrasound and CDFI. 相似文献
102.
We assessed the mechanics and morphology of the lung in 165 rats treated neonatally with either room air (RA), O2, RA + steroids, or O2, + steroids. Newborn Sprague-Dawley male rats were randomly assigned to these groups. O2,-exposure (0.96-1.0 FiO2 lasted 5 days, and dexamethasone treatment consisted of eight daily S.C. injections of drug or buffer in successive doses of 0.5,0.4.0.3,0.2,0.1, 0.1. 0.1. and 0.1 mg/kg. At 58 days, right ventricular systolic pressure (RVP) was measured. At 60 days, all rats were sacrificed for obtaining lung weight and DNA, saline pressure-volume (P-V) curves, and morphometry. We weighed right ventricles (RV) and left ventricles + septa (LV). Hyperoxia alone did not, but steroid decreased survival rate to 79.4% (95.3% in RA rats, P < 0.02). Only 21 of 40 (52%) O2 + steroids rats survived, less than in both RA groups (P < 0.001). RV weight, RVP and muscularization of alveolar duct arteries were significantly increased in O2 vs. RA rats. In RA + steroids rats, weight of the LV was decreased but RV, RVP, and lung vasculature were not affected. These effects were additive in the O2 + steroid group. Wet lung weights and DNA were increased for RA + steroid rats over all others. O2 and steroids shifted the P-V curve to the left and O2+ steroids still further. Maximal lung volume increased significantly with RA + steroids and still further in O2 + steroids but not in O2 alone. O2 and steroids significantly increased the mean linear intercept and O2 + steroids even more so. In O2- and steroid-treated rats, the parenchymal air space increased. In conclusion, both neonatal hyperoxia and steroid administration caused aberrations in the growth of lung and connective tissue. The effects of the two were additive. The vascular system, maximal lung volume, and DNA responded differently, presumably by different modes of action. Pediatr Pulmonol. 1993; 16:81–88. © 1993 Wiley-Liss, Inc. 相似文献
103.
Hilary Eadon Marlene Rose Richard O'Neill Neil Leaver Magdi Yacoub 《Transplant international》1995,8(1):35-40
Pharmacokinetic profiles were obtained for 16 heart or lung recipients following the administration of identical doses of cyclosporin as oral solution and capsules on consecutive days. A comparison of pharmacokinetic parameters (AUC, Cmax, Cmin and tmax) showed that there were no significant differences between the two formulations except for the tmax, which was significantly longer for the capsules. The mean variation in day-to-day trough levels produced by the two different forms was 25.6%. A retrospective study was carried out of consecutive cyclosporin levels in patients at steady state on oral solution. The mean variation in day-to-day trough levels was 32.3%. This was not significantly different from the variation in consecutive trough levels seen in the oral solution/capsule comparison. This study shows that cyclosporin capsules can be substituted for oral solution without causing acute changes in cyclosporin blood levels, and that the pharmacokinetics of the two formulations are similar.This work was carried out in partial fulfillment of the requirements for the Master of Science Degree in Clinical Pharmacy, University of London 相似文献
104.
高频超声检测颈动脉内膜-中层厚度及外周血管内皮功能评价动脉粥样硬化 总被引:1,自引:0,他引:1
目的 探讨高频超声检测颈动脉内膜-中层厚度与肱动脉内皮依赖性舒张功能在动脉粥样硬化中的诊断价值.方法 冠状动脉造影的老年患者69例及青年志愿者20例,分别行颈动脉超声检查,同时采用充气加压法测定肱动脉血流介导的内径扩张值,超声测值与冠脉造影结果对照分析.结果 ①颈动脉内膜-中层厚度值随粥样硬化斑块的增多、冠脉狭窄程度的加重而增高;②动脉粥样硬化患者在内膜-中层厚度值增高之前即可出现内皮功能损伤,肱动脉内径扩张值降低早于内膜-中层厚度值增高之前出现,内径扩张值随冠脉狭窄程度加重而下降.结论 高频超声检测颈动脉内膜-中层厚度、内径扩张值诊断早期动脉粥样硬化敏感性高,并且有助于对冠脉狭窄程度作出判断. 相似文献
105.
聂树涛 《中国医师进修杂志》2007,30(10):33-35,49
目的用药物敏感试验预测肺癌合并恶性胸腔积液癌细胞对顺铂联合其他药物的敏感度,观察其在指导此类患者的顺铂联合其他化疗药物胸腔内化疗的价值。方法将44例胸腔积液癌细胞阳性肺癌患者随机分为两组:药物敏感试验组(20例,有2例因体外药物敏感试验失败而被排除)和对照组(22例)。药物敏感试验组患者用三磷酸腺苷-肿瘤细胞药物敏感试验(ATP-TCA)法分别检测胸腔积液癌细胞对顺铂加香菇多糖、顺铂加甘露聚糖肽、顺铂加A群链球菌制剂、顺铂加干扰素、顺铂加金黄色葡萄球菌滤液制剂、顺铂加卡介苗多糖核酸、顺铂加红色诺卡菌细胞壁骨架、顺铂加白细胞介素-2的敏感度,并选择抑瘤率最高的联合化疗药物对患者进行胸腔内化疗,观察治疗后胸腔积液完全缓解率及胸腔积液癌细胞转阴率,并与对照组比较。结果药物敏感试验组患者对各联合化疗药物敏感的例数为:顺铂加香菇多糖14例、顺铂加甘露聚糖肽18例、顺铂加A群链球菌制剂17例、顺铂加干扰素10例、顺铂加金黄色葡萄球菌滤液制剂16例、顺铂加卡介苗多糖核酸15例、顺铂加红色诺卡菌细胞壁骨架17例、顺铂加白细胞介素-216例。药物敏感试验组完全缓解率为65.0%,对照组为27.3%(P〈0.05)。药物敏感试验组胸腔积液癌细胞转阴率为80.0%,对照组为45.5%(P〈0.05)。结论用药物敏感试验指导肺癌合并恶性胸腔积液的胸腔内个体化化疗可提高完全缓解率和胸腔积液癌细胞转阴率,该方法具有临床实用价值。 相似文献
106.
沐舒坦治疗重型颅脑损伤后肺部感染的临床分析 总被引:1,自引:0,他引:1
目的:探讨沐舒坦对重型颅脑损伤后肺部感染的治疗作用.方法:选择GCS3~8分重型颅脑损伤后肺部感染的患者90例,随机选45例(实验组)加用沐舒坦治疗,另45例(对照组)未予沐舒坦治疗。所有患者其他治疗措施均基本相同。结果:实验组有42例感染控制,感染控制时间平均(7.8±2.6)d:对照组有35例感染控制,感染控制时间平均(14.1±3.2)d。实验组肺部感染控制率显著高于对照组(P<0.05),而控制感染平均时间显著短于对照组(P<0.05)。结论:沐舒坦治疗重型颅脑损伤后肺部感染有较好的临床疗效,值得临床推广应用。 相似文献
107.
OBJECTIVE: To compare the outcome of urgent haemorrhoidectomy with conservative treatment for prolapsed thrombosed internal haemorrhoids. METHODS: A prospective randomised study of 50 patients with prolapsed thrombosed internal haemorrhoids was carried out using clinical and ultrasonic outcome measures. Peri-operative bed occupancy and the presence of symptoms at 6 and 24 months were compared. Endoanal ultrasonic scanning was carried out to investigate anal sphincter integrity in those patients willing to be studied. RESULTS: The median length of hospital stay for the group treated conservatively; 2 nights (range 1-9 nights) was significantly shorter than for the group treated by urgent haemorrhoidectomy; 4 nights (range 1-12 nights, P < 0.01). There was no difference between treatment groups in the number of patients with symptoms at six or 24 months. Urgent haemorrhoidectomy was associated with a significantly higher incidence of endosonographically detected anal sphincter damage in 18 patients: 66%vs 0% (P = 0.009). CONCLUSION: Conservative treatment for prolapsed thrombosed internal haemorrhoids is associated with shorter in patient stay and less anal sphincter damage compared with operative treatment. 相似文献
108.
Christina Djokoto George Tomlinson Stephen Waldman Marc Grynpas Angela M. Cheung 《Journal of clinical densitometry》2004,7(4):448-456
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS. 相似文献
109.
110.
K. H. Vogelberg M. Mühl M. Köhler 《Journal of molecular medicine (Berlin, Germany)》1987,65(15):713-718
Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献