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11.
Lesion evolution during focal cerebral ischemia may depend on flow restrictions or on accumulation of toxic mediators within the infarct and expansion of these factors to the periinfarct region. So far, the precise contribution of flow dependent versus spreading-mediated impairment of viable periinfarct tissue has not been determined. Therefore, we measured lesion expansion, flow restrictions and glutamate distribution on serial brain sections at different time points after experimental focal ischemia.Permanent focal ischemia was induced by occlusion of the right middle cerebral artery in male rats and the flow reduction was subsequently measured at 1, 12 and 24 h using iodo[14C]antipyrine autoradiography. Additionally, the necrotic volume was determined on serial brain sections and the glutamate content was measured in tissue samples from adjacent microdissections.Twelve hours after focal ischemia no noteworthy viable areas with blood flow restrictions of 20-40 ml 100 g− 1 min− 1 existed but at 24 h the necrotic tissue exceeded the hemodynamically compromised region by 40 ± 21 mm3 (24%). Furthermore, at 12 and 24 h the glutamate content was elevated in areas surrounding the infarct.Relevant flow restrictions are detectable only during early stages of infarct maturation, whereas the propagation of secondary factors may be the predominant mechanism for delayed infarct evolution.  相似文献   
12.
目的探讨官腔镜下官腔肌性粘连分离术的临床应用。方法回顾性地分析了2003年6月至2007年6月在我院接受官腔镜下官腔肌性-粘连分离术的34例病人的临床资料及随访结果。结果34例宫腔肌性粘连病人均成功地实施了官腔镜下粘连分离术,无一例发生并发症,术后随访6~40个月均有正常月经来潮,27例有生育要求者,19例获得妊娠。结论官腔镜下宫腔肌性粘连分离术是安全有效的,值得推广。  相似文献   
13.
目的观察卡维地洛对不稳定型心绞痛(UAP)患者高敏C反应蛋白(hs-CRP)、白介素-6(IL-6)及细胞间可溶性黏附分子1(sICAM-1)水平的影响。方法UAP患者62例采用完全随机化方法分成对照组(n=30)和治疗组(n=32),在常规抗血小板、扩血管治疗基础上,对照组予美托洛尔(12.5mg,2次/d×3d)口服,治疗组服卡维地洛(6.25mg,2次/d×3d),在治疗前后分别测定hs-CRP、IL-6、sICAM-1值。结果对照组和治疗组在治疗前hs-CRP、IL-6、sICAM-1均无显著性差异;用药后两组3指标均较用药前显著降低(P<0.05);治疗组在用药后IL-6、sI-CAM-1显著低于对照组(P<0.05)。同时,用药后两组患者的心率、血压、心肌耗氧量均较用药前显著降低(P<0.05),治疗组的心肌耗氧量显著低于对照组(P<0.05)。结论卡维地洛可显著降低UAP患者的炎症因子IL-6、sICMA-1水平。  相似文献   
14.
目的探讨急性高血压性脑出血患者细胞间粘附分子-1(ICAM-1)在血肿周围脑组织和正常脑组织中的表达及其意义。方法选择30例行开颅手术治疗的急性高血压性脑出血患者,采用免疫组化技术检测ICAM-1在血肿周围脑组织及正常脑组织中的表达。结果实验组血肿周围脑组织可见ICAM-1的表达水平上调,其表达水平明显高于正常脑组织的表达水平(P<0.01)。神经元和血管内皮细胞共同表达ICAM-1,且神经元表达较明显。结论ICAM-1在人类高血压性脑出血血肿周围脑组织的表达水平上调,其表达上调可能参与了血肿周围脑组织的白细胞浸润,最终引发炎性反应和继发性脑损伤。  相似文献   
15.
Mutations in PAX6/Pax6 lead to a variety of ocular anomalies in humans and mice. The aim of the study was to characterise the ocular abnormalities caused by the missense Pax6Leca4 mutation and compare them to published observations on Pax6 alleles that are functionally equivalent to Pax6 null alleles (such as Pax6Sey and Pax6Sey-Neu) and human inherited eye diseases. Ocular features of homozygous Pax6Leca4/Leca4 and heterozygous Pax6Leca4/+ embryos at E12.5-E18.5, heterozygous Pax6Leca4/+ young mice at P18 and heterozygous Pax6Leca4/+ adults at 12 weeks were analysed histologically with their wild-type Pax6+/+ littermates. Homozygous Pax6Leca4/Leca4 fetuses died perinatally with no eyes although an optic cup rudiment with pigmented cells developed. Pax6Leca4/+ mice were microphthalmic and a range of other severe ocular phenotypes affected both the anterior and the posterior segments. In contrast to Pax6+/−, the Pax6Leca4/+ eyes had no goblet cells in the corneal epithelium, the iris was not hypoplastic and there was no lens-corneal epithelial plug. However, microphthalmia was more severe, corneal vascularisation occurred earlier (during fetal stages), pigmented cells were present in the vitreous and corneal stroma and the ciliary body was malformed or abnormal. These results show that, although Pax6Leca4/+ lacked some eye abnormalities commonly seen in Pax6Sey/+ and Pax6Sey-Neu/+ eyes, in most respects their eyes were more severely affected. These differences probably reflect both differences between the Pax6Leca4 and the Pax6Sey-Neu mutations and differences in modifier gene expression in different genetic backgrounds. The presence of pigmented cells in the cornea is a novel observation. Some Pax6Leca4/+ ocular abnormalities were similar to those present in human Peters' anomaly and persistent hyperplastic primary vitreous (PHPV) so Pax6Leca4/+ mice provide a useful model for some inherited eye diseases.  相似文献   
16.
目的探讨缺氧条件对卵巢癌细胞Caov-3体外黏附和迁移能力的影响。方法在常氧和缺氧条件下培养卵巢癌细胞Caov-3,分别用四甲基偶氮唑蓝(MTT)比色法和细胞迁移试验测定常氧和缺氧条件下培养的Caov-3细胞体外黏附和迁移能力。结果缺氧条件下,Caov-3细胞在Matrigel和纤维连接蛋白Fn基质上黏附数量增加,黏附促进率分别为17.1%和15.2%,与常氧条件下比较有显著性差异(P<0.05)。缺氧条件下,Caov-3细胞在Matrigel基质上迁移距离增大,分别为258.8±19.5μm和331.3±24.4μm,迁移促进率为28.0%,与常氧条件下比较有显著性差异(P<0.05)。结论缺氧环境对卵巢癌细胞Caov-3体外黏附和迁移具有明显的促进作用。  相似文献   
17.
We studied the alteration of intracellular signal transduction using quantitative autoradiography of the second messenger system in order to clarify the mechanisms of delayed neuronal damage in the remote areas of rat brain after transient focal ischemia. Chronological changes of [3H]forskolin binding sites were measured to demonstrate the striatal-nigral pathway after 90 min of right middle cerebral artery (MCA) occlusion and after such occlusion followed by 3 h, 6 h, 1 day, 3 days, 1 week, 2 weeks and 4 weeks of recirculation. [3H]Forskolin binding sites were found to be markedly decreased in the lateral segment of the caudate putamen supplied by the occluded MCA after 90 min of ischemia with no recirculation. On the contrary, there was no alteration on day 1, but 3 days after ischemic insult, marked reduction of [3H]forskolin binding sites was observed in the ipsilateral substantia nigra which lay outside the ischemic areas. This postischemic delayed phenomenon observed in the substantia nigra developed concurrently with 45Ca accumulation, which was detected there in our previous study. The delayed reduction of [3H]forskolin binding sites in the substantia nigra observed in the present study indicates that striatonigral terminal degeneration at presynaptic sites is caused by precedent ischemic damage of the ipsilateral caudate putamen and that exo-focal postischemic neuronal death is caused by a transsynaptic process associated with the ischemic foci.  相似文献   
18.
Focal segmental glomerulosclerosis   总被引:3,自引:0,他引:3  
Over the last 2 decades, we have learnt that focal segmental glomerulosclerosis (FSGS) is a ubiquitous phenomenon underlying the progressive deterioration of many different types of renal diseases in both pediatric and adult populations. FSGS may also be the primary renal lesion, whether in new disease entities such as glycogen storage disease and human immunodeficiency virus infection, or in idiopathic FSGS. Although the mechanism which triggers the development of primary FSGS still remains unknown, laboratory and clinical studies have identified several key pathophysiological events leading to end-stage renal disease. While therapeutic modalities have not changed remarkably, a recent study, although uncontrolled, demonstrated an impressive efficacy of intravenous steroid pulse therapy in inducing remission. Nevertheless, it remains largely unknown whether such a forced remission decreases the overall risk of developing chronic renal failure. Studies have revealed an important pathophysiological role of angiotensin and the therapeutic efficacy of angiotensin converting enzyme inhibitors in progressive loss of renal function in diseases where glomerulosclerosis is secondary; however, it remains to be verified whether these results hold true in primary FSGS. As a result of the improvement in allograft survival rate, the benefit of renal transplant outweighs the risk of recurrence of FSGS, hence transplantation continues to be a vital therapy for FSGS patients who have reached renal failure. Thus, FSGS is not one disease, but rather a range of lesions seen in many settings. The type of lesions and the patient's unique genetic factors contribute to prognosis, and also may dictate choice of optimum therapy.  相似文献   
19.
The adhesion and accumulation of oral streptococci on saliva-coated hydroxyapatite was examined in strains representing species that appear in initial plaque ( Streptococcus sanguise FC1 and Streptococcus oralis C5) and in more mature plaque ( Streptococcus gordonii G9B). Washed cells of strains FC1 and C5 did not attach better to saliva-coated hydroxyapatite than did strain G9B, suggesting that the degree of initial adhesiveness does not alone account for the temporal appearance of these bacteria in dental plaque. Growing cells of each strain were also examined for their ability to accumulate on saliva-coated hydroxyapatite. The addition of sucrose to the medium promoted the accumulation of strain G9B more than it promoted the accumulation of strains FC1 and C5. Sucrose also enhanced the accumulation of adhesion-defective mutants of each strain to levels similar to those of the respective parent strains. These results suggest that sucrose-dependent accumulation may facilitate the colonization of the tooth surface by these species of oral streptococci when adhesion is limited by reduced bacterial adhesiveness or limited pellicle-binding sites.  相似文献   
20.
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