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71.
目的研究金匮实脾法对实验性肝纤维化大鼠胶原纤维合成与降解的影响。方法采用四氯化碳实验性肝纤维化模型,用金匮实脾法代表方鳖甲煎丸口服液治疗干预,与γ-干扰素对照;测定肝功能、血清透明质酸,并通过光镜观察肝组织病理变化和纤维化程度,用苦味酸-天狼红染色和氨银-Masson网织纤维染色观察Ⅰ、Ⅲ型胶原,免疫组织化学法检测Ⅳ型胶原及组织金属蛋白酶抑制因子1(TIMP-1)的表达。结果鳖甲煎丸口服液组与模型组比较,可改善肝功能指标,显著降低血清透明质酸;明显改善Ⅰ、Ⅲ、Ⅳ型胶原纤维增生,减少TIMP-1表达。结论金匮实脾法可通过改善胶原纤维的增生起到抗肝纤维化作用。  相似文献   
72.
兔角膜基质细胞在壳聚糖胶原共混膜体外培养研究   总被引:5,自引:1,他引:5  
目的 探讨壳聚糖 胶原共混膜作为载体体外培养兔角膜基质细胞的可行性。方法 先同时消化角膜上皮及内皮层 ,然后刮去上皮、内皮、前弹力层和后弹力层 ,将剩余的基质层剪碎消化 ,接种在壳聚糖 胶原共混膜上 ,通过间接免疫荧光细胞化学染色对培养的细胞进行鉴别。结果 角膜基质细胞应用消化培养法 4h后部分基质细胞与壳聚糖 胶原共混膜有贴壁现象出现 ,细胞呈梭形。培养 2 4h后 ,基质细胞呈纺锤形且透明 ,此后细胞分裂增殖越来越多并向周围延伸 ,培养第 6天细胞已经达到完全融合状态 ,呈梭形 ,排列比较整齐。在 6d左右达到 10 0 %融合状态 ,间接免疫荧光细胞化学染色、Vim染色、胞浆染色阳性。结论 传代的细胞具有角膜基质细胞的生物特性 ,壳聚糖 胶原共混膜适合角膜基质细胞传代培养  相似文献   
73.
PURPOSE: We assessed the results of collagen injection for female sphincteric incontinence using strict subjective and objective criteria. MATERIALS AND METHODS: We evaluated 63 consecutive women with sphincteric incontinence who underwent a total of 131 transurethral collagen injections. Sphincteric incontinence was confirmed by urodynamics. All patients were treated with 1 to 5 transurethral collagen injections and treatment outcome was classified according to a new outcome score. Cure was defined as no urinary loss due to urge or stress incontinence documented by a 24-hour diary and pad test, and patient assessment that cure was achieved. Failure was defined as poor objective results and patient assessment that treatment failed. Cases that did not fulfill these cure and failure criteria were considered improved and further classified as a good, fair or poor response. RESULTS: Mean patient age plus or minus standard deviation was 67.7 +/- 12.8 years. All women had a long history of severe stress urinary incontinence, 18 (29%) underwent previous anti-incontinence surgery, and 41% had combined stress and urge incontinence. Preoperatively diary and pad tests revealed a mean of 7.5 +/- 4.6 incontinence episodes and 152 +/- 172 gm. of urine lost per 24 hours. Overall 1 to 5 injections were given in 26, 17, 13, 3 and 4 patients, respectively. Mean interval between injections was 4.4 +/- 5.7 months, mean followup was 12 +/- 9.6 months, and mean interval between the final injection and outcome assessment was 6.4 +/- 4.9 months. There was a statistically significant decrease in the total number of incontinence episodes per 24-hour voiding diary after each injection session. Although there was a clear trend toward decreased urinary loss per 24-hour pad test, statistical significance was not established. Using the strict criteria of our outcome score overall 13% of procedures were classified as cure, 10%, 17% and 42% as good, fair and poor, respectively, and 18% as failure. CONCLUSIONS: As defined by strict subjective and objective criteria, we noted a low short-term cure rate after collagen injection in women with severe sphincteric incontinence. It remains to be determined how patients with less severe incontinence would fare using our outcome assessment instruments.  相似文献   
74.
75.
Stretch of nerve has been reported to decrease the amplitude of the compound action potential (CAP) with a complete block appearing in approximately 30 minutes. But for the most part, those experiments were carried out in vivo, and it is generally accepted that the failure of responses was due to a closure of vessels supplying the nerve with a resulting ischemia and anoxia. These studies were undertaken to determine if stretch of nerve has effects that are independent of interference with its vascular supply. In the studies, lengths of rat sciatic and dog peroneal nerves were removed and placed in a chamber supplied with oxygen in which their CAPs were continuously elicited and recorded. This in vitro preparation obviated interference with the nerve's metabolism on stretching. We have previously shown that the form change termed 'beading,' appearing within 10 seconds and reversing as quickly on relaxation, can be elicited with tensions of only several grams. We wished to determine if stretch adequate to produce beading could alter CAPs with the same rapidity. Tensions below 2 g had little effect. On applying tensions of 10-100 g, levels well above those needed to bead the fibers, both increases and decreases of CAP amplitude were seen. The changes occurred within 10 seconds of stretch application, the time at which beading arises with stretch. Although the decreases of CAP amplitudes could be accounted for by beading, the degree of CAP change did not correspond to the amount of tension applied. We hypothesize that the constrictions in the beaded fibers increase axial resistivity and diminish local currents so as to block conduction. The lack of an increasing degree of decreased CAP amplitude with increases in tension is ascribed to the inhibition of elongation offered by the collagen fibrils present in nerve. Collagenase applied to nerves allowed a further increase in length, producing a 'hyperbeading,' showing much longer lengths of beading constrictions on stretch. This would further increase axial resistance and is taken to account for the greater decreases of CAP amplitudes seen following collagenase treatment. To account for those cases where increases of CAP amplitude were seen on stretch, we hypothesize that stretch can also cause an increase in the excitability of the nodes. The outcome of stretch in any given nerve would be the resultant of two opposing actions; beading of the internodes causes a decrease of local currents leading to block of CAPs, while an increased excitability of the nodes acts to augment the responses.  相似文献   
76.
目的 :考察重组人白细胞介素 10 (rhIL 10 )对可溶性鸡Ⅱ型胶原 (SCCⅡ )治疗大鼠佐剂性关节炎(AA)疗效的影响。方法 :通过测量足肿胀度、体重、胸腺与脾脏系数 ,观察不同部位淋巴细胞ConA增殖反应并检测腹腔巨噬细胞 (PMΦ)与滑膜组织细胞(SMCs)产生IL 1的水平。结果 :与SCCⅡ(0 .0 3mg·kg-1·d-1,ig)或IL 10 (1,2 μg·d-1,sc)单独治疗比较 ,二者联合治疗大鼠AA ,明显改善上述观察指标 ,同时使SCCⅡ的口服耐受诱导期缩短 ,增强了治疗效果。结论 :IL 10能提高SCCⅡ治疗大鼠AA的治疗效果。  相似文献   
77.
目的:比较长脉宽1064 nm Nd:YAG激光和Q开关1064 nm Nd:YAG激光照射对小鼠皮肤的影响.方法:分别使用长脉宽1064 nm Nd:YAG激光(脉宽为3 ms、50 ms)和Q开关1064 nm Nd:YAG激光(脉宽5 ns)对小鼠背部脱毛后的皮肤进行照射,共照射4次,每次间隔1周.检测照射后不同时间点的皮肤弹性、皮肤羟脯氨酸含量,真皮内胶原增生情况以及红斑指数和经表皮失水量的变化情况.结果:从首次照射后第3或4周至第7周,各实验组的皮肤弹性都明显好于对照组;首次照射7周后各组实验侧的皮肤羟脯氨酸含量和真皮内胶原厚度都较对照组显著增大(P<0.01),但各实验组之间无显著差异;苦味酸一天狼猩红染色-偏振光法检查显示各组增生的胶原主要为I型胶原.首次激光照射后即刻,各实验组的经表皮失水量及Q开关1064 nm Nd:YAG激光实验组的红斑指数都较其对照组显著增高(P<0.01),并于1周内恢复.结论:长脉宽1064 nm Nd:YAG激光可以取得与Q开关1064 nm Nd:YAG激光对皮肤相似的效果,且不良反应较轻.  相似文献   
78.
目的:探讨纳米羟基磷灰石/胶原(nHAC)作为支架材料对兔自体富血小板血浆(PRP)体外诱导兔骨髓基质干细胞(rBMSCs)向成骨细胞分化能力的影响。方法:兔自体PRP分别作用于与nHAC联合培养的rBMSCs及常规培养的rBMSCs,利用扫描电镜观察rBMSCs在nHAC上的生长情况;通过碱性磷酸酶(ALP)活性测定,骨钙素(OCN)含量测定,骨桥蛋白(opn)mRNA相对表达量的分析,比较两种培养条件下兔自体PRP诱导rBMSCs向成骨细胞分化能力上的差异。结果:联合培养的rBMSCs在nHAC上生长良好,其ALP活性、OCN含量均较常规培养明显增加,且opn mRNA相对表达量是常规培养组的4.78倍。结论:nHAC作为支架材料可明显提高兔自体PRP诱导rBMSCs向成骨细胞分化的能力。  相似文献   
79.
目的:探讨莪术醇抑制A549细胞增殖作用及分子机理。方法:MTT法观察莪术醇对A549细胞增殖的抑制作用;天狼猩红染色法检测莪术醇对A549细胞层分泌胶原的影响;流式细胞术检测细胞周期阻滞。结果:莪术醇对A549细胞增殖有抑制作用,并能抑制细胞胶原分泌;细胞周期分析显示,莪术醇作用细胞24h,主要通过增加G1期细胞比例来抑制细胞增殖,作用48h主要影响了细胞的G2期。结论莪术醇能抑制肺腺癌A549细胞增殖,其机制可能是与莪术醇抑制ECM中胶原的分泌、诱导细胞周期阻滞有关。  相似文献   
80.
凉血活血中药治疗放射性肺损伤的实验研究   总被引:4,自引:0,他引:4  
目的研究凉血活血中药干预对大鼠放射性损伤肺内胶原纤维动态变化及肺组织白介素-6(IL-6)、转化生长因子-β(TGF—β)表达的影响,探讨其防治放射性肺损伤的作用及机制。方法160只Wistar雌性大鼠随机分为单纯照射组(模型组,40只)、照射加中药组(治疗组,40只)、单纯中药组(40只)和正常对照组(40只)。对模型组和治疗组大鼠右肺进行分次照射,各组分别灌胃给予相应药物或生理盐水,于照射开始后第3、5、8、12、26周5个时间点每组分别处死8只大鼠,行肺组织HE、天狼猩红染色、免疫组化染色,观察大鼠肺组织中Ⅰ型和Ⅲ胶原纤维的含量及分布的动态变化及IL-6和TGF-8的表达。结果首次照射后第3周模型组大鼠肺组织出现成纤维细胞增生,随着照射次数的增多和观察期的延长,Ⅰ型胶原明显增多,Ⅰ/Ⅲ型胶原比例明显升高,在各个观察点均明显高于治疗组(P〈0.01)。模型组大鼠肺组织IL-6和TGF-8的表达分别于照射第8周及第12周达到达高峰(P〈0、01);治疗组大鼠各时相IL-6、TGF-8均明显低于模型组(P〈0、01)。结论早期应用凉血活血中药可抑制致炎因子和致纤维化因子的表达,抑制肺组织内胶原蛋白的合成,减轻Ⅰ/Ⅲ型胶原比例的失调,从而减轻早期放射性肺炎的炎症反应和后期放射性肺纤维化程度。  相似文献   
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