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61.
62.
目的 探讨硝普钠结合控制性再灌注在预防肺缺血再灌注损伤中的作用及其机制。方法 将 1 4只猪随机分为对照组 (Ⅰ组 )和实验组 (Ⅱ组 )。对照组在去除肺动脉阻断 ,恢复自体血流前 ,给予控制性再灌注处理 (灌注液 :去白细胞∶改良Buckberg液 =4∶1 ,灌注压 1 8mmHg ,灌注时间 1 0min ,温度 37℃± 1℃ )。实验组在去除肺动脉阻断 ,恢复自体血流前 ,给予控制性再灌注 ,后经肺动脉以每分钟 1 .0 μg kg注入硝普钠 1 0min ,余处置同对照组。 0 .5 ,1和 2h后测血氧分压、肺血管阻力、肺顺应性及肺氧合功能变化 ,实验结束后 ,取肺组织测NO含量、MDA含量及肺含水量。结果 实验组的左肺氧合功能和肺顺应性明显好于对照组 (P <0 .0 5 )。肺循环阻力、丙二醛 (MDA)值及肺含水量均低于对照组 (P <0 .0 1 )。实验组肺中NO含量较对照组明显升高 (P <0 .0 1 )。结论 硝普钠结合控制性再灌注能明显降低肺缺血再灌注损伤 ,起到了较好的移植肺保护效果 相似文献
63.
目的 了解中缅边境一线县、二线县、及一线三个县的一线自然村、二线自然村的疟疾流行情况,为制定边境地区疟疾防治措施提供科学依据。方法 采用IFAT对中缅边境沧源、耿马及孟连一线县与双江县、永德县二线县,边境线3县一线自然村和二线自然村进行疟血清流行病学调查,用电脑软件EPI6X2检验法进行数据分析。结果一线县抗体阳性率23.88%(568/2379),二线县抗体阳性率1.40%(10/712),一线县显著高于二线县(x2=180.54;P<0.01)。一线县的一线自然村抗体阳性率33.05%(467/1413),二线自然村抗体阳性率10.46%(101/966),一线自然村显著高于二线自然村(x2=159.92;P<0.01)。结论IFAT抗体阳性率和阳性GMRT说明靠近边境地带比远离边境的地带疟疾流行更为严重。应加强出入境人员的防治工作,才能控制边境疟病流行。 相似文献
64.
The characteristics of the binding sites for 2-[125I]iodomelatonin were studied in chicken brain membranes during development. Specific binding, defined using cold melatonin (1 microM), was detected as early as 8-day-old embryos. Scatchard analysis of saturation experiments showed that 2-[125I]iodomelatonin binds to a single class of site at all ages tested (8-day-old embryos to 3-month-old chicks). Binding affinity (Kd) did not change during development (18-31 pM), but the maximal number of binding sites (Bmax) increased until embryonic day 18, and then remained relatively constant until 30 days of age. A further increase in Bmax was seen at 3 months of age. Guanosine 5'-triphosphate (GTP, 1 mM) inhibited 2-[125I]iodomelatonin binding at all ages suggesting that the melatonin binding site is coupled to a guanine nucleotide binding protein at a very early stage of development. Competition experiments with a number of melatonin analogues indicated that the binding site detected in the brain at embryonic day 8 was pharmacologically identical to that observed 15 days after hatching. 相似文献
65.
A rare case of carpal tunnel syndrome due to an extra-articular synovial osteochondroma arising from the synovial sheath of the flexor pollicis longus tendon, is described. This has not been described in the literature previously. The cyst with the contained osteochondroma was excised with good relief of symptoms. The histological examination of the osteochondroma revealed another interesting and unusual feature. We would like to document a case of tenosynovial chondrometaplasia of the synovial lining of a tendon sheath. Only a few such cases have been reported in the literature. 相似文献
66.
Background. Malignant changes in burn scars occasionally develop, the majority being squamous cell carcinoma. Malignant melanomas (MMs) arising in burn scars occur rarely.
Objective. To present the case of a patient with a multiple MM developed at different burn scar areas.
Methods. A case report and review of literature are given.
Results. One was a large pigmented nodular lesion with central ulceration on right flank. It was widely excised and revealed lentigo MM. After that, we took notice another small pigmented lesion on right arm. It was also reported lentigo MM.
Conclusion. This case provided a valuable lesson. Another kind of tumor may be present even if one tumor is found by pathologic observation, especially in burn scar patients. Clinicians should carefully observe burn scars, chronic ulcers, and other pigmented lesions. 相似文献
Objective. To present the case of a patient with a multiple MM developed at different burn scar areas.
Methods. A case report and review of literature are given.
Results. One was a large pigmented nodular lesion with central ulceration on right flank. It was widely excised and revealed lentigo MM. After that, we took notice another small pigmented lesion on right arm. It was also reported lentigo MM.
Conclusion. This case provided a valuable lesson. Another kind of tumor may be present even if one tumor is found by pathologic observation, especially in burn scar patients. Clinicians should carefully observe burn scars, chronic ulcers, and other pigmented lesions. 相似文献
67.
目的 利用诱发电位技术探讨正常人听觉P50特征.方法 应用美国Nicolet Bravo脑电生理仪,采用条件刺激(S1)-测试刺激(S2)模式对45名健康受试者作了听觉P50检测.结果 分析了基本波型,提出了Cz和Pz区域P50诸指标平均值.结论 听觉P50电位具有抑制性特征,其变化可反映大脑正常感觉门的功能状态.P50较佳表达式是波幅S1-S2和100(1-S2/S1)两种结合,能直接显示感觉门的程度.此正常值可供抑郁症研究时参考. 相似文献
68.
Reversal of fulminant hepatic failure using an extracorporeal liver assist device. 总被引:20,自引:0,他引:20
N L Sussman M G Chong T Koussayer D E He T A Shang H H Whisennand J H Kelly 《Hepatology (Baltimore, Md.)》1992,16(1):60-65
Liver transplantation is currently the only effective therapy for patients with fulminant hepatic failure. The availability of an artificial liver could bridge these patients through the relatively brief crisis period and allow their own livers to regenerate, providing a more favorable outcome and sparing the trauma and expense of transplant. We have developed a device consisting of a highly differentiated human liver cell line cultured in a hollow fiber cartridge. This device is capable of supporting dogs with acetaminophen-induced fulminant hepatic failure for a period long enough for their own livers to resume function. Even though liver function tests such as albumin and prothrombin time became extremely abnormal during the course of the experiment, the dogs did not become encephalopathic. Two of the three treated animals recovered sufficient liver function after 42 to 48 hr of treatment that they could be disconnected from the device, and they survived the experiment. Histological results and serum ALT levels suggest that the device affected the course of the disease in two animals, allowing recovery of hepatocytes that would otherwise have lysed. In the third animal, regenerative nodules demonstrated that, even in the presence of severe liver injury, the device was capable of supporting total liver function. 相似文献
69.
First results are presented to determine the maturity of fetal lung by sonography. Using the fetal liver as a reference-organ we are avoiding the known pitfalls which made it impossible in the past to standardize the fetal lung changes depending on the age of gestation. We examined 104 patients between week 27 and week 41. In one ultrasound section cut we depicted as well lung and liver. According to the known A-mode we registered frequencies in both organs. The registered frequencies were entered digitally into a computer and checked for f(mean), f(max) and f(min). Afterwards the frequencies of the lung were divided by those of the liver. Of all weeks of gestation the mean value and standard deviation were calculated. We found the liver as an adequate reference-organ, since there is no change of the reflection pattern between the different weeks of gestation, while there are significant changes to be registered in the fetal lung, a cutting line being week 35. A quotient of f(mean) lower than 1.1 hints to lung maturity while values over 1.1 point to immaturity. This was confirmed by several cases of analysis of amniotic fluid (L/S-ratio). Further comparisons with amniotic fluid results will have to validate these findings. 相似文献
70.
Desirability of an action, often referred to as utility or value, is determined by various factors, such as the probability and timing of expected reward. We investigated how performance of monkeys in an oculomotor serial reaction time task is influenced by multiple motivational factors. The animals produced a series of visually-guided eye movements, while the sequence of target locations and the location of the rewarded target were systematically manipulated. The results show that error rates as well as saccade latencies were consistently influenced by the number of remaining movements necessary to obtain a reward. In addition, when the animal produced multiple saccades before fixating a given target, the first saccade tended to be directed towards the rewarded location, suggesting that saccades to rewarded location and visual target might be programmed concurrently. These results show that monkeys can utilize information about the required sequence of movements to update their subjective values. 相似文献