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51.
Eighteen Coopworth ewe lambs were divided into three groups based on the initial cystourethrogram and cystometry findings at 5 – 7 weeks of age: group 1, 6 lambs with spontaneous low-pressure bilateral vesicoureteric reflux (VUR) on bladder filling were used to study the natural history of reflux; group 2, 5 lambs with no VUR detected were used to establish an experimental model of bilateral VUR using an unroofing surgical procedure; group 3, 7 lambs with spontaneous VUR detected during micturition had the same surgical procedure to increase the degree of VUR. All three animal groups were followed for 4 – 10 months. Spontaneous VUR was demonstrated in 13 of 18 lambs (25/36 ureters). The presence and severity of spontaneously occurring reflux in group 1 lambs diminished with increasing age. VUR was created successfully in group 2 and increased in degree in group 3 animals. The only significant histological finding in all three animal groups with grades II and III VUR was distal renal tubular dilatation. The sheep is a useful and readily available animal for studying VUR. During 4 – 10 months of follow-up, sterile reflux without bladder outflow obstruction resulted in distal renal tubular dilatation, but no renal parenchymal damage. Received April 17, 1997; received in revised form August 5, 1997; accepted August 21, 1997  相似文献   
52.
主动脉瓣机械瓣置换术后交替脉   总被引:1,自引:0,他引:1  
报道4例因主动脉瓣关闭不全行主动脉瓣置换术后的患者在术后早期出现脉搏交替现象,此时心电图为整齐的窦性心律,所记录的脉搏图形高低交替,如扪诊桡动脉时则会发现桡动脉搏数为心电图示心率的一半。患者术后均顺利恢复,显示这一现象为一过性的、良性的过程。推测这一现象出现的原因可能是术后早期主动脉瓣不再有回流,因而巨大的左室腔充盈不足,加之左室收缩力尚低,不能在每次收缩时都能射出同等量的血流所致  相似文献   
53.
Immunoluminometric assays for lactoferrin and elastase-alpha 1-proteinase inhibitor complexes were developed using solid-phase methodology, which has already been published from this laboratory. The aim of the study was to develop a rapid method to see whether elevated granulocyte activity was present in the lung, as for example in neonatal sepsis. The lactoferrin assay gave reliable results within 30 minutes, the elastase-alpha 1-proteinase inhibitor complexes, within 5 hours. The correlation between both analytes was good, so that the lactoferrin assay could replace the elastase-alpha 1-proteinase inhibitor assay in emergency cases. The lactoferrin assay was used for rapid answer, the elastase-alpha 1-proteinase inhibitor complex assay for "fine" monitoring of the progress of the disease. Both assays could be used to measure concentrations in plasma or bronchoalveolar lavage using a 10 microliters sample. Plasma for the elastase-alpha 1-proteinase inhibitor complex determination had to be diluted 1:50 before being assayed. Only EDTA plasma was used in the assay, as either heparin plasma or serum resulted in granulocyte destruction, thus giving rise to elevated, and non-reproducible results. The results from bronchoalveolar lavage show an excellent correlation between elastase-alpha 1-proteinase inhibitor complexes and lactoferrin. No interference was seen from lipaemic or icteric plasma samples. Results from haemolytic samples i.e. where lysis of erythrocytes and leukocytes had occurred, had to be treated with care if no clinical indication of intravascular haemorrhage was present. The assays lend themselves to perinatal diagnosis, as the total volume of plasma or lavage needed is theoretically under 50 microliters, i.e. ethically acceptable for regular monitoring of neonates.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
54.
本实验用纯系CFW小鼠与Wistar大鼠建立“虚证”模型。以环核苷酸系统反应性为指标观察了肉桂挥发油的作用。通过气相色谱及气质联用等方法研究表明,本实验所提取的挥发油中桂皮醛含量约为92%。肉桂挥发油可显著降低“阳虚”——甲状腺素缺乏(甲减)模型升高了的cGMP系统反应性而使其降低了的耗O_2率升高;这是一种治疗作用。肉桂挥发油可显著升高“阴虚”——甲状腺素过多(甲亢)模型已升高了的cAMP系统反应性并使其升高了的耗O_2率进一步升高,这是一种恶化作用。这两种作用与中医对症治疗的原则是一致的。  相似文献   
55.
目的 探讨心理疗法对防治SARS的作用,方法 本文综合国内外心理疗法研究成果,提出了应对非典的心理处方:“接纳恐惧,顺其自然;平衡思维,端正认识;积极暗示,增强信心;切已体察,心理常态”;结果 从原理上解释其发生作用的机制,明确心理处方的实际操作,提出具体的步骤和要点,并对日常生活中的不妥做法进行了剖析。结论 采用心理疗法可增强抗击“非典”的信心及提高免疫功能。  相似文献   
56.
57.
目的 :了解当归注射液改善脑循环治疗脑血栓的临床效果。方法 :对 46例脑血栓形成患者应用当归注射液进行治疗 ,对比分析其治疗前后血浆前列环素 (PGI2 )、血栓烷A2 (TXA2 )及自由基水平。结果 :脑血栓形成患者TXA2 、丙二醛 (MDA)明显升高 ,超氧化物岐化酶 (SOD)明显降低。当归注射液治疗后上述改变明显减轻或恢复至正常组水平。结论 :当归注射液能有效调节花生四烯酸代谢产物和氧自由基水平 ,对治疗脑血栓效果明显。  相似文献   
58.
本文探讨了5/6肾切除术后慢性肾衰大鼠残肾纤维化的发生机理,发现术后120天,在残肾单个核炎性细胞浸润、残肾显著纤维化和肾功能损害的同时,残肾脂质过氧化物含量显著升高,抗氧化机制功能显著下降,钠钾ATP酶活力显著下降,周围血单个核细胞内游离钙浓度显著升高,单个核细胞培养上清白介素-1活性增高。而摄入大量维生素E的大鼠,上述各指标有不同程度的改善,残肾纤维化显著减轻。提示残肾纤维化可能与单个核白细胞内游离钙浓度升高,进而产生白介素-1增多有关。  相似文献   
59.
Sindbis viruses have been widely used in neurobiology to express a variety of genes in cultured neurons, in cultured slices, and in vivo. They provide fast onset and high levels of expression of foreign genes, but the expression is limited to a short time window due to a shut-off of host protein synthesis. We have used a mutation in an essential gene (nsP2) of the life cycle of Sindbis, which allows the functional analysis of changes in protein expression for >/=6 days after infection. This Sindbis mutant (nsP2) was used to express enhanced green fluorescent protein (EGFP) in hippocampal neurons in culture and in vivo without any sign of toxicity, based on two-photon imaging and electrophysiology. In addition, the EGFP mutant virus can be injected in vivo to visualize spines and other details of neuronal structure. The Sindbis mutant described here provides an improved tool in neurobiology with reduced cytotoxicity and a prolonged time window of expression for novel applications in imaging and behavior. In addition, the use of this vector for the functional expression of mammalian voltage-gated ion channels in organotypic slices is demonstrated.  相似文献   
60.
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