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991.
IgA抗精子抗体对精子顶体反应的影响 总被引:3,自引:0,他引:3
目的 探讨精浆中IgA抗精子抗体对人精子顶体反应的影响。方法 利用免疫珠法(IBT)筛选出IgA抗精子抗体阳性精浆标本同正常人精子孵育,以孕酮诱发精子顶体反应;以特异性荧光标记物.络合异硫氰酸荧光素的花生凝集素(FITC-PNA)标记精子顶体,通过流式细胞仪检测精子顶体完整性。结果 与IgA抗精子抗体阳性精浆孵育的精子,其孕酮诱发的顶体反应发生率明显低于正常精浆及精子培养液组(P〈0.01),正常精浆组及精子培养液组间无显著性差异(P〉0.05);IgA抗精子抗体阳性精浆组、正常精浆组、精子培养液组自发顶体反应的发生率无显著性差异(P〉0.05)。结论 免疫性不育患者精浆中的IgA抗精子抗体可以明显抑制孕酮诱发的顶体反应的发生,可能是导致不育的原因之一。 相似文献
992.
993.
Liu JM Zhao HY Ning G Zhao YJ Chen Y Zhang Zh Sun LH Xu MY Chen JL 《Calcified tissue international》2005,76(1):1-6
The correlations between the serum levels of OPG, RANKL with age, menopause, bone markers, and bone mineral densities (BMDs) at the lumbar spine and proximal femur were studied in 504 pre- and postmenopausal Chinese women aged 20–75 years. We found that age was positively and negatively correlated with serum concentrations of OPG (r = 0.442, P < 0.001) and RANKL (r = –0.263, P < 0.001), respectively. Compared with premenopausal women, postmenopausal women showed higher serum OPG levels (107.6 ± 3.0 vs 72.0 ± 1.8 pg/ml, P < 0.001), lower serum RANKL concentrations (4.7 ± 0.4 vs. 5.8 ± 0.3 pg/ml, P < 0.001) and RANKL/OPG ratios (0.045 ± 0. 004 vs. 0.099 ± 0.008, P < 0.001). Neither serum levels of OPG nor RANKL or RANKL/OPG ratio correlated with BMDs after adjustment of age and menopause. They also showed no differences among normal, osteopenic and osteoporotic postmenopausal women. Serum levels of OPG were positively correlated with urinary excretion of NTx (r = 0.1453, P = 0.006). Serum levels of RANKL (r = –0.1928, P < 0.001) and RANKL/OPG ratio (r = –0.1303, P = 0.013) were inversely correlated with serum concentrations of OC. In multiple regression analysis, up to 20% variance (R2 = 0.106–0.224) of the OPG-RANKL system in peripheral circulation can be explained by age, menopause and bone markers.These results suggest that although serum OPG and RANKL concentrations were unrelated with BMDs, the age– and menopause– dependent changes of serum OPG and RANKL might be a protective mechanism against the accelerated bone loss in postmenopausal women. 相似文献
994.
Application of covered stent grafts for intracranial vertebral artery dissecting aneurysms 总被引:1,自引:0,他引:1
He M Zhang H Lei D Mao BY You C Xie XD Sun H Ju Y Zhang JM 《Journal of neurosurgery》2009,110(3):418-426
OBJECT: Utilization of covered stent grafts in treating neurovascular disorders has been reported, but their efficacy and safety in vertebral artery (VA) dissecting aneurysms needs further investigation. METHODS: Six cases are presented involving VA dissecting aneurysms that were treated by positioning a covered stent graft. Two aneurysms were located distal to the posterior inferior cerebellar artery, and 4 were located proximal to the posterior inferior cerebellar artery. Aspirin as well as ticlopidine or clopidogrel were administered after the procedure to prevent stent-related thrombosis. All patients were followed up both angiographically and clinically. RESULTS: Five of the 6 patients underwent successful placement of a covered stent graft. The covered stent could not reach the level of the aneurysm in 1 patient with serious vasospasm who died secondary to severe subarachnoid hemorrhage that occurred 3 days later. Patient follow-up ranged from 6 to 14 months (mean 10.4 months), and demonstrated complete stabilization of the obliterated aneurysms, and no obvious intimal hyperplasia. No procedure-related complications such as stenosis or embolization occurred in the 5 patients with successful stent graft placement. CONCLUSIONS: Although long-term follow-up studies using a greater number of patients is required for further validation of this technique, this preliminary assessment shows that covered stent graft placement is an efficient, safe, and microinvasive technique, and is a promising tool in treating intracranial VA dissecting aneurysms. 相似文献
995.
Calles-Vázquez Mdel C Viguera FJ Sun F Usón JM Usón J 《Journal of pediatric surgery》2005,40(9):1428-1435
Background/Purpose
Alternatives are still being sought in vascular surgery to address the problem of arrested growth after anastomosis in growing vessels, and opinions differ widely regarding the most suitable technique. This study compared vascular growth and permeability after anastomosis using the latest-generation vascular closure staple (VCS) system and the conventional suture technique to ascertain which approach yielded better results.Methods
Thirty 55-day-old lambs underwent end-to-end anastomosis of the carotid artery and jugular vein. Serial ultrasonography and angiography were carried out over the ensuing 6-month growth period, after which lambs were euthanized.Results
Both VCS clips and polypropylene suture allowed longitudinal and transverse vessel growth; however, longitudinal growth was significantly greater in clip-closed vessels than in either sutured or untreated vessels.Conclusions
The results obtained for vascular growth and permeability suggest that VCS clips may provide a suitable alternative to conventional suture in pediatric vascular surgery. 相似文献996.
腹腔镜肝门肠吻合术治疗胆道闭锁的探讨(12例报告) 总被引:1,自引:0,他引:1
目的:探讨经腹腔镜辅助行肝门解剖和肝门肠吻合术治疗先天性胆道闭锁的临床效果。方法:先天性胆道闭锁患儿12例,29~87d11例,5.5个月1例。2例为肝总管闭锁(Ⅱ型),肝门部有直径1.2~2.5cm囊肿与肝内胆管相通;10例为肝门部胆管闭锁(Ⅲ型)。于脐部纵切口置入10mmTrocar,然后分别于右上腹、右中腹和左上腹置入3个5mmTrocar。术中胆道造影,确诊为胆道闭锁,暴露肝门;切除胆囊,游离切除肝门纤维块,空肠行Roux-en-Y吻合术保留肝支30~35cm,然后将肠管送回腹腔,将空肠肝支经结肠后拉至肝门下;用5-0可吸收缝线将空肠与肝门端侧连续吻合。结果:本组12例患儿中1例因肝门渗血中转开腹手术;另11例均在腹腔镜辅助下完成手术,手术时间平均为3.5h(3.1~4.6h),出血量约10ml,没有需在术中和术后输血者,全组患儿无手术后肠粘连梗阻和腹腔感染。结论:经腹腔镜行肝门肠吻合术治疗先天性胆道闭锁安全可靠,具有暴露肝门清晰、肝门纤维块分离和切除准确、对患儿打击小等优点。 相似文献
997.
目的:采用免疫组织化学的方法研究慢性肝损伤时肝干细胞在肝脏内的分布和增值,初步探讨肝脏的损伤修复与肿瘤发生的细胞生物学机制。方法:3,-me-DAB喂食大鼠四周,建立应激模型刺激大鼠肝内干细胞的迅速增殖,取材、固定制成石蜡切片,ABC法检测肝干细胞特异性的表面标记蛋白CD34、C-11、CK19、OV6和神经前体细胞的特异性表面标记Nestin在大鼠肝脏内的表达。结果:大鼠肝实质结构改变显著,汇管区内结缔组织细胞大量增生,浸润周围肝组织形成假小叶。靠近界板处断续的排列着卵圆样细胞分别表达CD34、CK19、OV6和Nestin,阳性细胞的形态和分布特点相似,而且具有典型的干细胞的特点。此外,肝实质内可见大量的单个核样干细胞分别表达OV6、CD34、Nestin和CK19。这些细胞类似造血系统来源的单核细胞分布在肝索、肝血窦、肝内血管、增生的小叶间胆管和胆管之间,多见于汇管区的结缔组织内。结论:3’-me-DAB作用后,肝内存在着多种干细胞,而且具有空间分布的规律性。增生的干细胞在损伤应激下继续增殖分化为肝实质细胞,参与肝脏的组织修复,同时成为引发肝脏肿瘤的可能原因之一,具体机制还需要进一步的深入研究。 相似文献
998.
Jiange Qian MD Wenzhong Li PhD Guocheng Zhang MD Liangbin Yan MS Wei Sun PhD † 《Dermatologic surgery》2005,31(1):23-26
BACKGROUND: Preservation of hair follicle units for the purpose of delayed transplant will help us graft thousands of hair grafts at one session, even in a clinic with fewer assistants and less equipment. OBJECTIVE: This study was undertaken to evaluate and compare the viability of hair follicle units preserved at 0 and 4 degrees C for various periods. MATERIALS AND METHODS: Cell cultures and transplant of hair follicle units into athymic mice were performed. RESULTS: Outer root sheath cells could be cultivated in 96% (0 degrees C group) and 92% (4 degrees C group) of the hair follicles after 24 hours of preservation, whereas 85% (0 degrees C group) and 79% (4 degrees C group) of the follicles implanted into the mice regrew well after the same period of preservation. Then, in both the 0 degrees C and the 4 degrees C group, these rates decreased significantly with length of preservation in cell cultures and mice transplant; however, 0 degrees C seems better than 4 degrees C for preservation of grafts (p<.05). CONCLUSION: Grafts are better preserved at 0 degrees C instead of 4 degrees C. When delayed transplant is an option, it should be completed within 24 hours and no later than 48 hours. 相似文献
999.
目的探讨血红素氧合酶-1(HO-1)对移植的异种心脏的保护作用及其可能机制。方法应用NI H小鼠到Wistar大鼠颈部异位心脏移植模型,术前对供者分别用HO-1的诱导剂CoPP或HO-1的阻滞剂ZnPP进行处理,术后受者相应接受CoPP或ZnPP处理,部分受者同时接受环孢素A(CsA)处理,并设空白对照组和单用CsA组。分别用免疫组化、逆转录聚合酶链反应、Westernblot蛋白印迹杂交等检测移植心组织中HO-1、HO-1mRNA、凋亡蛋白酶-3以及信号传导与转录因子-3(STAT-3)的表达,测定心肌组织中HO-1的活性,采用原位末端标记法检测心肌细胞凋亡情况,比较不同处理因素之间的差异。结果单一接受CoPP者(CoPP组)移植心脏存活时间长于空白对照组及单一接受ZnPP者(P<0.01),但短于同时接受CoPP和CsA处理者(CoPP CsA组,P<0.01);CoPP组及CoPP CsA组HO-1、HO-1mRNA的表达及HO-1的活性均高于其余各组(P<0.01),其心肌细胞凋亡数和凋亡蛋白酶-3低于其余各组(P<0.05),而STAT-3高于其余各组(P<0.01)。结论CoPP诱导产生的HO-1可延长NI H小鼠到Wistar大鼠异种移植心脏的存活时间,该作用可能与STAT-3激活、凋亡蛋白酶-3受抑制而导致心肌细胞凋亡发生率下降有关。 相似文献
1000.
Cell proliferation and neuronal differentiation in the dentate gyrus in juvenile and adult rats following traumatic brain injury 总被引:3,自引:0,他引:3
Sun D Colello RJ Daugherty WP Kwon TH McGinn MJ Harvey HB Bullock MR 《Journal of neurotrauma》2005,22(1):95-105
It is well known that the cognitive functions of juveniles recover to a greater extent than adult patients following traumatic brain injury (TBI). The exact mechanisms underlying this age-related disparity are unknown; however, we speculate that this improved recovery in juveniles following TBI may be associated with an endogenous neurogenic response in the hippocampus. We, therefore, examined the effects of TBI on cellular proliferation and differentiation in the dentate gyrus (DG) of the hippocampus in juvenile and adult rats following lateral fluid percussion injury (FPI). The temporal profile of the injury-induced proliferative response was determined using BrdU labeling at varying survival times. The differentiation of these newly generated cells was investigated using cell-type specific markers. We found that, following injury, there was a significant increase in cell proliferation in the DG in both injured juveniles and adults at 2 days post injury when compared to shams. When comparing the extent of cell proliferation between juveniles and adults following TBI, the absolute number of cells generated in the subgranular zone (SGZ) was far greater in the juveniles. Moreover, the percentage of newly generated cells in the SGZ that differentiated into neurons was nearly two times higher in the juveniles as compared to adults. Conversely, more glial differentiation was observed in the DG of adult rats. These findings provide compelling evidence that age-related differences in the neurogenic response to injury may underlie the differences observed in cognitive recovery in juvenile mammals as compared to adults following TBI. 相似文献