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91.
目的:探讨病态肥胖患者行腹腔镜胃减容术时,3种机械通气参数对患者氧合情况的影响。方法:选择行腹腔镜胃减容术的病态肥胖24例,按手术时间顺序分为3组,每组8例。A组:潮气量12ml/kg,呼吸频率10次/min;B组:潮气量20ml/kg,呼吸频率10次/min;C组:潮气量12ml/kg,呼吸频率20次/min。分别于气腹前(T1)、气腹后(T2)抽取动脉血测量pH、PO2、PCO2、Plat(平台压)、Peak(峰压)、AaDO2(肺泡-动脉氧分压差)。结果:气腹后B组Plat(33.2±1.8)cmH2O、Peak(36.3±1.6)cmH2O显著高于A组Plat(29.5±3.9)cmH2O(q=3.053,P〈0.05)、Peak(33.0±2.9)cmH2O(q:2.823,P〈0.05)和C组Plat(28.0±4,1)cmH2O(q:4.290,P〈0.05)、Peak(31.8±2.8)cmH2O(q:4.704,P〈0.05)。其他观察指标无统计学差异。结论:病态肥胖患者在腹腔镜下施行胃减容术时,加大潮气量20ml/kg或加快呼吸频率20次/min不能改善患者的氧合情况。  相似文献   
92.
高浓度瘦素自分泌诱导脂肪细胞瘦素抵抗的研究   总被引:1,自引:0,他引:1  
李小林  赵锋  巫国辉  袁铿 《中国美容医学》2007,16(12):1696-1699
目的:观察高浓度瘦素对人脂肪细胞分解代谢及脂肪蓄积的直接影响,探讨瘦素自分泌调节在肥胖发生中的作用。方法:取正常成人皮下脂肪组织,常规提取和培养前脂肪细胞,待细胞融合后诱导分化为脂肪细胞后分为二组:低浓度组、高浓度组;分别培养于瘦素终浓度为100ng/ml、1000ng/ml的培养液a中。于培养48h、72h收集培养液检测游离脂肪酸和甘油的浓度,取脂肪细胞行油红O染色并图像分析计算脂肪细胞中脂肪颗粒的积分光密度。结果:与低浓度组相比,瘦素作用48h、72h后,高浓度组培养液中游离脂肪酸浓度均下降[(0.16711±0.011900)mmol/L VS(0.20589±0.008738)mmol/L,(0.17544±0.013920)mmol/L VS(0.23567±0.026220)mmol/L,甘油含量均减少(28.1733±0.91377)μmol/L VS(30.2456±0.30084)μmol/L,(28.9367±0.79530)μmol/L VS(31.8567±0.79024)μmol/L],而脂肪颗粒积分光密度则升高(461136.89±12049.947 VS418570.33±5668.129,441566.56±5921.602 VS 390133.67±7001.304)。结论:高浓度瘦素长时程作用脂肪细胞,可延缓脂肪分解代谢,增加脂肪蓄积。高浓度瘦素经自分泌诱导脂肪细胞产生瘦素抵抗,可能对肥胖发生有重要影响。  相似文献   
93.
Objective To study the effect and mechanism of transplanting spinal fetal neural stem cells (NSCs) into the peripheral nerve for delaying muscle denervation atrophy. Methods Spinal. fetal NSCs were separated from spinal cord of enceinte 10 to 12 days SD rats, cultured and purified. After three passages, the formed NSC spheres were blew into single cell suspension ( 106/μl×5 μl) and transplanted into the distal part of the transected tibial nerve. 5 μl of cell culture medium was injected into the distal tibial nerve in the control group. Three and 5 months after the transplantation, the distal part of the tibial nerve and the triceps suraes were harvested and identified with specific markers, by means of indirect immunofluorescent staining to evaluate survival and differentiation of transplanted NSCs in the nerve, and to observe the neuromuscular junctions.Results Compare to the control group, atrophy of the triceps suraes muscle was less severe 3 and 5 months after NSCs transplantation. Postsynaptic membrane was also better preserved in NSCs transplanted group. Five months after NSCs transplantation, new synapses (neuromuscular junction) formed in the denervated muscle.Conclusion NSCs transplantation can delay atrophy denervated muscles. NSCs transplantation can not only maintain the structure of postsynaptic membrane, but also form new synapse with the denervated muscle.  相似文献   
94.
Use of bioactive cationic peptides as gene carriers is limited by instability of their DNA complexes in vivo and by the loss of their biological activity due to undesired interactions of their bioactive parts with the DNA. To overcome the two major limitations, biodegradable high-molecular-weight form of TAT peptide (POLYTAT) sensitive to cellular redox-potential gradients was synthesized in this study by oxidative polycondensation. Physicochemical and transfection properties of DNA polyplexes based on POLYTAT were investigated and compared with polyplexes based on TAT polymer prepared by in situ template-assisted polymerization. Physicochemical properties of TAT-based polyplexes were affected by the molecular weight and method of polymerization of the TAT peptide. All TAT-based DNA polyplexes exhibited reduced cytotoxicity when compared with control polyethylenimine (PEI) polyplexes. Polyplexes based on both high-molecular-weight TAT polypeptides exhibited increased transfection efficiency compared to control TAT peptide but lower than that of PEI polyplexes. The evidence shows that transfection activity of TAT-based polyplexes is strongly dependent on the presence of chloroquine and therefore suggests that TAT polyplexes are internalized by an endocytosis. Overall, high-molecular-weight reducible polycations based on bioactive peptides has the potential as versatile carriers of nucleic acids that display low cytotoxicity and can prove to be especially beneficial in cases that require surface presentation of membrane-active or cell-specific targeting peptides.  相似文献   
95.
96.
三种实验性IgA肾病模型的比较   总被引:4,自引:0,他引:4  
目的探讨建立一种理想的IgA肾病(IgAN)动物模型方法。方法分别采用葡聚糖G200、大肠杆菌外膜蛋白和金葡菌的细胞膜20肽抗原决定簇诱导小鼠IgA肾病模型。用分子生物学和病理学方法对3组IgAN模型小鼠进行鉴定和比较。结果(1)葡聚糖组尿蛋白增高,伴有血尿;免疫荧光显示部分肾小球大量IgA沉积;光镜下肾小球系膜细胞增多,肝和脾可见弥漫性的粉染物质沉积;电镜下肾小球系膜区少量低电子密度的致密沉积物,肝和脾可见淀粉丝样物质沉积。(2)大肠杆菌外膜蛋白组尿蛋白增高,伴有血尿;免疫荧光显示肾小球有少量IgA沉积;光镜下肾小球系膜细胞轻度增多,间质炎细胞浸润明显;电镜下肾小球系膜区无电子致密沉积物。(3)金葡菌细胞膜20肽抗原决定簇组尿蛋白增高,伴有血尿;免疫荧光显示多数肾小球均可见大量IgA沉积;光镜下肾小球系膜细胞增多,伴系膜基质轻度增生;电镜下肾小球系膜区和基底膜的内皮细胞下可见高电子密度的致密沉积物。结论金葡菌细胞膜20肽抗原决定簇组诱导的IgAN模型从临床表现和病理学变化与人IgAN极其相似,是3种IgAN模型中最理想的IgAN模型。  相似文献   
97.
后路减压植骨融合3D脊柱内固定系统治疗腰椎滑脱症   总被引:1,自引:0,他引:1  
[目的]观察3D脊柱内固定系统对腰椎滑脱症的固定及治疗效果。[方法]2004年1月~2005年7月,对42例腰椎滑脱症患者(其中,男28例,女14例)运用椎板减压、椎管后外侧植骨融合、3D椎弓根螺钉内固定系统治疗,随访13~32个月(平均25.3个月)。[结果]术前JOA评分平均4.48分的42例患者,随访时14.5分(P<0.01),术后15个月内动态X线检查显示3D椎弓根螺钉固定患者植骨融合率100%,融合节段稳定,临床症状改善优良率92.8%。[结论]后路运用3D内固定系统行椎管后外侧植骨融合内固定对腰椎滑脱症患者是一种安全、有效的术式,近期疗效满意。  相似文献   
98.
With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased.  相似文献   
99.
目的 探讨肱骨髁间骨折的手术方式并评价疗效。方法 1998年1月~2004年12月共手术治疗肱骨髁间骨折28例,进行随访分析。结果 28例中26例获随访,时间6个月~4年7个月,其中22例获2年以上随访。疗效评价参照casse‰。评分系统,优良率为65%。结论 骨折类型及手术方式直接影响预后。关节良好的复位和牢固的固定,以及术后早期积极的功能锻炼是得到良好疗效的保证。  相似文献   
100.
Preparation and characterization of porous hollow silica nanoparticles (PHSN) for controlled release applications were investigated. Through orthogonally designed experiments, the optimal synthesis conditions for the preparation of PHSN were obtained and the produced PHSN were characterized by BET, SEM, TEM and IR. Scanning and transmission electron microscopy images revealed their hollow shell-core structure and also demonstrated that the size and shape of PHSN are determined by the templating CaCO3 nanoparticles. The produced PHSN were applied as a carrier to study the controlled release behaviors of Brilliant Blue F (BB), which was used as a model drug. Being loaded into the inner core and on the surfaces of the nanoparticles, BB was released slowly into a bulk solution for about 1140 min as compared to only 10 min for the normal SiO2 nanoparticles, thus exhibited a typical sustained release pattern without any burst effect. In addition, higher BET of the carriers, lower pH value and lower temperature prolonged BB release from PHSN, while stirring speed showed little influence on the release behavior. It showed that PHSN have a promising future in controlled drug delivery applications.  相似文献   
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