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51.
Earlier pharmacological screening showed that siculine syrup (a traditional herbal remedy purported to be useful in the prevention and treatment of sickle cell pain – crises, due to sickle cell anaemia – SCA) had antisickling and analgesic activities as well as antimicrobial and diuretic effects. SCA is an important haemoglobinopathy in Africa and many other communities/countries worldwide, with relatively high morbidity and mortality. The present study was to determine the effects of the extract on various isolated muscle preparations – smooth, skeletal and cardiovascular. Siculine (4–20 µg/mL), like acetylcholine (40–400 µg/mL), contracted the isolated rat uterus concentration dependently. Similar effects were observed with the guinea‐pig ileum and rabbit jejunum (2–20 µg/mL). In contrast to these effects, the direct (muscle) and indirect (nerve) stimulations of rat phrenic nerve–diaphragm were relaxed by siculine (4 and 8 µg/mL) and d ‐tubocurarine (0.8 µg/mL). Siculine also concentration‐dependently decreased both the rate and force of contraction of guinea‐pig atria and rabbit heart and also resulted in a fall in cat blood pressure in a manner similar to those of acetylcholine. The possible therapeutic and/or toxicological consequences of these effects including the hypotensive activity is noteworthy since siculine syrup is used by the local population for the prevention and treatment of sickle cell pain crises. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
52.
大鼠胰腺十二指肠移植的手术技巧   总被引:1,自引:0,他引:1  
目的探讨建立大鼠胰腺十二指肠移植模型的手术技巧。方法不阻断体循环,采用双套管将供胰所带腹主动脉、门静脉分别与受鼠的左肾动、静脉进行套管吻合,尽量减轻对全身血流动力学的影响;同时行十二指肠空肠端侧吻合引流胰液,重建胰腺外分泌途径;围手术期注意补液、保暖及抗凝。结果100例手术中83例手术成功,术后移植胰腺具有内分泌功能,胰腺轻度充血水肿。结论该移植模型不阻断体循环且操作简单实用,其成功的关键在于手术操作及围手术期处理。  相似文献   
53.
OBJECTIVE: It is well described that unilateral pelviureteric junction obstruction (PUJO) is a benign condition, because the dilatation resolves spontaneously and the function does not decrease in most of the kidneys. However, there is exceptional PUJO that requires emergent treatment in neonatal periods. The aim of this article is to report the urological emergency and management in neonates with PUJO. MATERIALS AND METHODS: Nine children (seven boys and two girls) with PUJO who underwent neonatal emergent treatment during the last 13 years were reviewed. Renal function was evaluated according to decay curve of serum creatinine (SCr) levels corresponding to gestational age (GA) at delivery. Physical examination, ultrasonographic monitoring, and chest and abdominal plain radiographs were repeated in each neonate. RESULTS: Eight patients were detected prenatally. In five patients, multicystic dysplastic kidney (MCDK) was demonstrated on the contralateral side. Three patients underwent percutaneous puncture of fetal hydronephrosis. Decrease of amniotic fluid was evident in three fetuses. Indications for emergent treatment included mass effect from hydronephrosis in three patients, renal dysfunction in five, and severe urinary tract infection in one. During neonatal periods, a percutaneous nephrostomy tube was placed in seven, and open nephrostomy in one with anorectal malformation. Repeated punctures of the dilated renal pelvis were done in one patient. Renal function after pyeloplasty was stable in eight patients, while it was moderately decreased in one who was associated with oligohydramnios in utero. CONCLUSION: Indications for emergent treatment in neonates with PUJO included mass effect from giant hydronephrosis, renal dysfunction and severe urinary tract infection. At birth, respiratory and circulatory conditions must first be stabilized. In neonates with hydronephrosis of the solitary kidney or severe bilateral PUJO, serial SCr should be monitored to evaluate renal function. Decrease of amniotic fluid suggested renal functional compromise that would not recover after urological management.  相似文献   
54.
Fas系统参与介导烧伤后心肌细胞凋亡及牛磺酸的影响   总被引:1,自引:0,他引:1  
目的观察Fas系统在烧伤后心肌细胞凋亡中的作用及牛磺酸的影响。方法选健康Wistar大鼠,随机分成对照组(Sham)、烧伤组(造成40%TBSAⅢ度烧伤)和牛磺酸保护组(烫伤后即刻腹腔注射牛磺酸400 mg/kg)。用原位末端标记(TUNEL)法检测凋亡细胞,RT-PCR检测Fas mRNA表达,免疫组化检测Fas/FasL和Caspase-8/3蛋白表达和荧光法分析Caspase-3活性。结果烧伤组大鼠伤后6 h和24 h心肌细胞凋亡指数分别为8.96±2.10和18.67±2.48,较对照组(0.92±0.34)有显著性升高,Fas蛋白阳性表达指数分别为13.51±1.56和14.55±1.89,也显著性高于对照组(2.46±0.75);Caspase-3活性分别为1.38±0.16和1.96±0.71,较对照组(0.35±0.06)有显著性差异。烧伤组凋亡指数与Fas表达之间有良好的相关性(r=0.86)。牛磺酸保护组细胞凋亡指数为2.14±0.68,Fas蛋白表达为3.71±0.82,Fas mRNA表达为0.17±0.03,Caspase-3活性为0.88±0.16,较烧伤组均有显著性降低。结论Fas系统参与了介导烧伤后心肌细胞凋亡,牛磺酸对烧伤后心肌细胞Fas表达及其信号转导有较好的拮抗作用。  相似文献   
55.
目的探讨自发性高血压大鼠颈动脉中抑癌基因P53和原癌基因c-jun、c-fos、c-myc mRNA的表达.方法用逆转录聚合酶链式反应检测两种基因的表达水平.正常雄性大鼠作为对照组.结果 SHR颈动脉中,抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,较WKY差异有显著性(P<0.05).结论自发性高血压大鼠颈动脉组织中抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,癌基因的活化可能与自发性高血压大鼠颈动脉血管重构有关.  相似文献   
56.
Diagnosis of perinatal infection in the newborn is difficult; there may be few clinical signs and current tests are slow or non-specific. Detection of organisms, antigen or specific antibody to common pathogens often requires repeat samples and does not give immediate results. Haematological parameters, although relied upon frequently to diagnose infection in the neonate prior to a positive bacterial isolation, are unreliable and insensitive. Indicators such as an increase in neutrophil band cell counts are highly variable between morphologists. Infection induces the expression of a number of T lymphocyte surface markers, including CD45RA/CD45RO and CD45RO. The use of changed expression of surface markers as a laboratory test for detection of infection in neonates was evaluated. We used multiparameter flow cytometry to detect expression of early (CD45RA/CD45RO) and late (CD45RO) activation markers. In the respective groups of 50 full term (including 25 normal vaginal deliveries and 25 caesarean deliveries) and 30 premature, i.e. < 36 weeks gestation (born by either normal vaginal delivery or caesarean delivery) the CD45RA isoform was brightly expressed on newborn ‘naive’ CD4+ T cells, whereas the CD45RO isoform (including both ‘bright’ and ‘dim’ populations) was present on < 19% of CD4+ T cells from these newborn infants. In a group of 37 infants, tested to evaluate possible effects of non-infective parameters such as respiratory distress and iso-immunization, no significant changes in surface marker expression were found and specificity of the test was confirmed. In 14 neonates with documented sepsis, up-regulation of dual staining CD45RA/CD45RO isoforms on CD4+ T cells was detected early in the infection. In addition, we found that CD45RO expression persisted for several weeks after bacterial infection, and up to several months in viral infection. In conclusion, detection of T cell activation by flow cytometry for the early diagnosis of neonatal infection is an easy test to carry out on small volumes of blood, is inexpensive, and may be a specific indicator of infection.  相似文献   
57.
Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc.  相似文献   
58.
本文报告谷参肠安胶囊大鼠长期毒性试验,结果表明,谷参肠安胶囊对动物的一般状况,体重增长、外周血象、肝肾功能及病理组织学检查等未见明显毒性。  相似文献   
59.
我们用麻醉的正常血压大鼠,大鼠的自体灌液后肢分别研究了美哌隆的降压作用强度、部位、维持时间和对心率的影响。实验结果提示:美哌隆降低动脉血压的作用除依赖于它对外周α_1受体的选择性阻滞外,还依赖于它对外周阻力血管的直接扩张作用。美哌隆在降压的同时也减慢心率,其降压作用和负性频率作用与剂量有关。  相似文献   
60.
Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) play an essential role in both normal and pathological extracellular matrix degradation, and a TIMP has been associated with at least one type of retinal degeneration. We have studied expression of MMP-2 and TIMP-1 by zymography, immunocytochemistry, and immunoblotting in the retinal pigment epithelium (RPE) from normal, aged and diseased retinas. MMPs and TIMPs were found in the rat RPE, interphotoreceptor matrix (IPM), and in media conditioned by human and rat RPE in culture. In other polarized cells, MMPs and TIMP-2 are secreted vectorially towards the basal lamina. In the RPE, however, MMP-2 and TIMP-1 were secreted preferentially from the apical surface, the surface bordering the IPM. These findings provide new evidence that MMPs and TIMPs could play a role in the turnover of IPM components.Cell homogenates and conditioned media from RPE isolated from mutant Royal College of Surgeons (RCS) rats with inherited retinal dystrophy had similar amounts of MMP-2 and TIMP-1 as those from congenic control rats. The secretion of MMP-2 and TIMP-1 from RPE cell cultures isolated from young and aged human donors varied widely. However, with increasing cell passage number, secretion of MMPs and TIMPs from human RPE increased dramatically. Also, growing human RPE on bovine corneal endothelial cell-generated extracellular matrix instead of plastic reduced the secretion of both MMPs and TIMPs. These data suggest that the integrity of Bruch's membrane may serve to regulate RPE functions in MMP and TIMP secretion and that extracellular matrices contain signals that regulate MMP and TIMP synthesis and/or secretion by the RPE.  相似文献   
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