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131.
The disaccharide trehalose is a key element involved in anhydrobiosis (the capability of surviving almost complete dehydration) in many organisms. Its presence also confers resistance to desiccation and high osmolarity in bacterial and human cells by protecting proteins and membranes from denaturation. The present study used a novel murine dry eye model induced by controlled low-humidity air velocity to determine whether topically applied trehalose could heal ocular surface epithelial disorders caused by ocular surface desiccation. In addition, the efficacy of 87.6 mM trehalose eyedrops was compared with that of 20% serum, the efficacy of which has been well documented. Mice ocular surface epithelial disorders were induced by exposure of murine eyes to continuous controlled low-humidity air velocity in an intelligently controlled environmental system (ICES) for 21 days, which accelerated the tear evaporation. The mice were then randomized into three groups: the control group received PBS (0.01M) treatment; a second group received 87.6 mM trehalose eyedrops treatment; and the third group received mice serum eyedrops treatment. Each treatment was administered as a 10 μl dose every 6 h for 14 days. The resultant changes in corneal barrier function and histopathologic examination of cornea and conjunctiva were analyzed and the level of apoptosis on the ocular surface was assessed using active caspase-3. After 14 days of treatment, the corneal fluorescein staining area, the ruffling and desquamating cells on the apical corneal epithelium, as well as the apoptotic cells on ocular surface epithelium had significantly reduced in eyes treated with trehalose compared with those treated with serum and PBS. In contrast, after 14 days of treatment, improvements in the thickness of the corneal epithelium, the squamous metaplasia in conjunctival epithelium and the number of goblet cells of the conjunctiva were less marked in eyes treated with trehalose compared with serum. These results demonstrated that trehalose could improve the appearance of ocular surface epithelial disorders due to desiccation through suppression of apoptosis. Trehalose produces some of the same responses as serum upon topical application and can maintain corneal health.  相似文献   
132.
远隔性小脑出血极为罕见,可见于多种类型的神经外科手术,一般出现在手术远隔部位,多分布于单侧或双侧小脑沟、蚓部,小脑上部出血也较为多见。远隔性小脑出血总体预后良好,病死率约为10%~15%。  相似文献   
133.
转移是膀胱癌患者死亡的主要原因,且早期以淋巴结转移为主。T2 期膀胱癌约 50%淋巴管内有癌细胞,T3 期几乎全部淋巴管内有癌细胞。残存的肿瘤细胞淋巴管浸润是肿瘤切除术后复发的根源,明显的淋巴结转移更是患者预后不良的重要危险因素。然而膀胱癌淋巴管浸润和淋巴结转移的  相似文献   
134.
自锁式防旋自动滑动加压钉板的研制与生物力学研究   总被引:1,自引:1,他引:0  
目的研制自锁式防旋自动滑动加压钉板(self—locking type pro-rotary auto-sliding&compression nail plate,LPSC—NP)用于股骨颈骨折内固定,对其进行生物力学性能测试,为临床应用提供依据。方法采集18具新鲜成年股骨近端标本,制成股骨颈骨折,分别用LPSC—NP、3枚空心钉、双头中空加压螺纹钉、动力髋螺钉内固定,并进行生物力学测试,用SPSS统计软件对实验数据进行分析。结果LPSC—NP的承载能力和抗扭转强度、刚度均明显大于后三者。结论LPSC—NP固定股骨颈骨折牢固可靠,符合生物力学要求。该器械结构合理,简单适用,有一定的临床价值。  相似文献   
135.
Cytokeratins (CKs) are expressed specifically in the cytoplasm of epithelial cells. We investigated the expression of CKs immunohistochemically in basal cell carcinomas (BCCs), epidermis overlying tumour, and skin tumor-associated amyloidosis (STA). Twenty cases of BCC, 11 of which had STA were included to the study. The primary antibodies of CK1-8 (AE3), CK10 (DEK-10), CK14 (LL002), CK17 (E3), CK18 (DC10), CK19 (KS19.1), CK 5/6/18 (LP34), CK8/18 (5D3) were applied to the section immunohistochemically. In BCCs without STA, CK1-8, CK14 and CK17 antibodies were expressed by tumour tissue in all biopsy specimens. In the BCCs with STA, tumour tissue was immunoreactive always with CK1-8 and CK17 antibodies, and commonly immunoreactive with anti-CK 14 antibody. In the epidermis overlying tumour tissue, there was positive immunoreactivity with anti-CK 1-8, CK 5/6/18, CK 10 and CK 14 antibodies in all biopsy specimens. Anti-CK 17 antibody was also positive in 17 biopsy specimens. STA is immunoreactive with anti-CK1-8 in all specimens. There was mild staining with anti-CK5/6/18 and with anti-CK19 whereas no immunoreactivity with anti-CK10 and CK18 antibodies was found. In conclusion, we could not find a significant CK expression difference between BCCs with and without STA. Weak positivity and a few number of CKs were shown in STA when compared with those of BCC and epidermis overlying tumour tissue expressing the more variable CKs. Interestingly, although CKs coexpressed in pairs consisting of one basic and one acidic CK, we detected predominantly basic CKs in STA.  相似文献   
136.
目的探讨内皮细胞生长因子(Endothelial cell growth factor,ECGF)诱导的血管内皮细胞(Vascular endothelial cell,VEC)增殖过程中FK506结合蛋白12(FK506 binding protein 12,FKBP12)表达的变化,为VEC的鉴定提供新的方法。方法培养大鼠VEC并传代。倒置显微镜下观察其在ECGF作用下的增殖情况,检测Ⅷ因子相关抗原、FKBP12和不同时期FKBP12 mRNA水平的表达。结果VEC表达FKBP12;VEC传代后第4天FKBP12 mRNA表达水平达到最高,6—8d下降。结论FKBP12既可作为VEC的标志物,又可反映VEC的增殖情况。  相似文献   
137.
S-F内固定器治疗胸腰椎爆裂型骨折   总被引:1,自引:1,他引:0  
目的 探讨使用S -F脊柱内固定器治疗胸腰椎爆裂型骨折的效果。方法 回顾分析从 2 0 0 0年 1月~ 2 0 0 2年 4月使用S-F脊柱内固定器治疗的胸腰椎爆裂型骨折 4 4例 ,比较手术前后的椎体前后缘高度 ,椎管狭窄程度 ,Cobb角及症状恢复情况。结果 经平均 2年左右的随访 ,术后椎体前缘平均高度达正常的 93 8%± 6 2 7% ,较术前增加了 4 2 5 3%。椎体后缘平均高度达到正常的 97 5 9%± 0 0 3% ,较术前增加了 1 6 5 2 %。脊柱后凸Cobb为 4 98°± 3 32°。较术前矫正了 1 4 6 8°。CT片显示椎体后突骨块占椎管前后径的比例为 9 5 9%± 7 2 1 % ,较术前减少 2 7 71 %。统计学分析差异有显著性 (P <0 0 5 )。有神经功能损伤者 ,术后平均改进一级以上。在术后二周与术后一年以上的X线片相比较其椎体前缘的高度平均仅丢失 1 0 % ,椎体后缘的高度平均丢失 0 8% ,Cobb角平均丢失 0 1°。结论 使用S -F脊柱内固定器治疗胸腰椎爆裂型骨折具有操作简单、复位完美、固定牢靠、疗效优良的优点。术中注意不宜过度撑开及双侧不对称 ,对椎板减压者宜作“H”型椎板后路植骨 ,横突间、关节突间植骨融合将提高疗效、减少并发症  相似文献   
138.
OBJECTIVE: To study the effect of combined transplantation of the liver and the pancreas in diabetic patients with end-stage liver disease, and explore the optimal surgical procedure. METHODS: Simultaneous orthotopic liver and heterotopic pancreas-duodenum transplantations were performed in a patient diagnosed as having chronic hepatitis B, hepatocirrhosis, hepatic cellular cancer, and insulin-dependent diabetes. Immunosuppression therapy utilized prednisone, tacrolimus (FK506), mycophenolate mofetil (MMF), and simulect. The function of the liver graft, serum amylase and lipase, blood glucose, and C-peptide were monitored after transplantation. RESULTS: Insulin was withdrawn at the 6th day after operation, good liver allograft functional recovery was achieved, without such complications as pancreatitis, thrombosis, and localized infections. CONCLUSION: End-stage liver disease with concomitant insulin-dependent diabetes is the indication for combined liver-pancreas transplantations, for which simultaneous orthotopic liver and heterotopic pancreas-duodenum transplantations may constitute the optimal surgical approaches as the primary choice.  相似文献   
139.
结直肠癌肝转移的外科手术治疗   总被引:1,自引:0,他引:1  
目的评价手术治疗对结直肠癌肝转移病人生存率的影响。方法回顾分析2000年1月1日至2004年12月31日复旦大学附属中山医院收治的363例结直肠癌肝转移病人,其中91例为手术病例,评价手术治疗对生存率的影响。结果160例同时性肝转移病人中手术切除肝转移灶22例(13.8%),203例延时性肝转移病人中手术切除肝转移灶69例(34.0%),两者相比差异具有统计学意义(P〈0.000)。同时性肝转移组手术死亡率(4.5%,1/22)高于延时性肝转移组(2.8%,2/69),两者相比差异有统计学意义(P〈0.05)。以2005年6月31日为随访终点,91例病人随访率100%,手术病人中同时性肝转移组1、3、5年生存率和中位生存时间与延时性肝转移组相似(P〉0.05),但术后复发率较高(36.4%vs21.7%,P=0.03)。363例病人中有36例具有手术指征而未手术病例,其1、3、5年生存率分别为47.9%、5.34%和0,明显低于91例手术病例(80.5%、33.0%和22.7%),(P=0.0034)。应用COX比例风险模型,对所有91例手术病人影响生存的因素进行多因素风险分析,得出手术切缘达1cm(β=-0.8351,P=0.0363)和复发后再次手术(β=-0.9428,P=0.0411)是生存的保护性因素,而术后复发(β=0.6471,P=0.0226)是生存的危险因素。结论手术治疗是结直肠癌肝转移的首选治疗措施,可以明显提高病人的术后生存。  相似文献   
140.
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