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991.
Intrauterine adhesions (IUAs) are a rare but significant cause of menstrual disturbance and infertility. Most cases are caused by uterine instrumentation. Several methods have been used to prevent IUAs in the past, which can be divided into two groups: pharmacological treatment and physical barrier. However, even with the liberal use of ancillary treatments to minimize reformation of adhesions, IUAs have a high rate of recurrence. Furthermore, medical literature of the last decades has only dedicated great attention to the restoration of normal anatomy in the uterine cavity, but not on the function of the endometrium. When the lesion of the endometrium is severe, especially intrauterine fibrosis, few basal layer is left which contains plenty stem cells to regenerate functional endometrium. Loss of endometrial stem cells directly causes the proliferation of fibrous tissue and subsequent synechiae. None of current treatments can compensate the defect of loss of stem cells. On the basis of existing researches, a novel intrauterine device (IUD) is recommended in this article. The new IUD consists of a light frame which contains two isolated drug-releasing system, one for estrogen and the other for cytokines to promote regeneration of endometrium such as growth factors, and a membrane in the middle of the frame which is also the carrier of endometrium stem cell. This device not only helps to preserve the original anatomy of the uterine cavity, but also to recover the function of endometrium. Experimental and clinical studies are now needed to testify the efficiency of the novel IUD in the prevention of IUAs. If there is a marked reduction in the IUAs and/or improvement of pregnancy success in the case group compared with the control group, our hypothesis will be confirmed. 相似文献
992.
Jingjing Li YaQi PanZhongyao Xu Qiyan WangDong Hang Na ShenMengfei Liu Chanyuan ZhangAmir Abliz Qiuju DengHong Cai Yang Ke 《Journal of virological methods》2013
FAP59/64, FAP6085/6319, and CUT primer sets were designed for detecting cutaneous HPV and have been used in many clinical and epidemiology studies. The FAP6085/64 primer set was first evaluated in this study and the FAP6085/64 combination was found to be much more sensitive than all three original primer sets by using HPV plasmids as a template. To confirm further the effectiveness of the FAP6085/64 primer set in human DNA templates, 90 palmar exfoliated cell DNA samples were used to detect the cutaneous HPV by both the FAP59/64 and FAP6085/64 primer sets. The overall proportion of HPV detection in those skin samples was 77.8% (70/90) using FAP6085/64, as compared to 55.6% (50/90) using FAP59/64. The FAP6085/64 primer set was also applied in a population based study. The proportion of HPV detection was 73.96% (2076/2807) in skin samples collected from healthy individuals, and a total of 336 different PV types were found. Sixty (17.9%) of them were fully characterized HPV types, 127 (37.8%) were putative HPV types which had been described previously, 149 (44.3%) were novel putative HPV types, and two animal PVs were also detected. These results suggest that the FAP6085/64 primer set was sensitive and effective for detection of cutaneous HPV in healthy skin samples. 相似文献
993.
Glucose‐insulin‐potassium (GIK) is a useful adjunct to myocarditis. Besides its essential action in energy metabolism, insulin also exerts an anti‐inflammatory effect. This study investigated the effect of insulin on myocardial inflammation in experimental autoimmune myocarditis (EAM) in mice and its potential role in T cell regulation. Mice were divided randomly into a normal control group, a saline‐treated EAM group and an insulin‐treated EAM group. The histopathological changes of myocardium, α‐myosin heavy chain (MyHCα)614–629 antigen‐specific autoantibody titre, the serum level of cardiac troponin I (cTnI), mitogen‐activated protein kinase (MAPK) family members' activity and content were measured. Furthermore, the phenotype of T lymphocyte subsets in splenocytes was analysed to evaluate the immune status of mice. Insulin reduced serum cTnI of EAM mice on days 14 and 21 (P < 0·05) after immunization, with no changes in blood glucose and autoantibody production. Western blot revealed that extracellular signal‐regulated protein kinase (ERK1/2) may be a determining factor in this process. Total ERK1/2 and phospho‐ERK1/2 (p‐ERK1/2) were both up‐regulated in insulin‐treated mice after immunization. We also found that insulin treatment promoted T cell recovery without changing the naive‐to‐memory T‐cell ratio; in particular, CD3+ T cells in insulin‐treated mice proliferated more vigorously than in control mice (P < 0·05). We report here for the first time that insulin alleviates myocarditis in the EAM model. These data show that insulin has a direct effect on T cell proliferation in EAM. It is possible that GIK or insulin may assist T cell recovery towards normal in myocarditis, especially for diabetic or hyperglycaemic patients. 相似文献
994.
背景:近年研究发现促红细胞生成素可以动员自体骨髓中的血管内皮祖细胞至外周血,趋化其至创面,促进创面血管新生。
目的:观察促红细胞生成素对血管内皮祖细胞动员效果的时效关系。
方法:不同剂量促红细胞生成素通过腹腔注射7 d动员小鼠血管内皮祖细胞,以注射生理盐水作为对照,采用流式细胞仪定点检测外周血中内皮祖细胞数量以比较动员效果,优选安全有效的促红细胞生成素动员剂量,并观察促红细胞生成素动员内皮祖细胞对脱细胞猪皮移植区血管新生的影响。
结果与结论:在开始注射后1,3,5,7,10,14 d等6个时间点内,生理盐水对照组外周血内皮祖细胞无明显变化,促红细胞生成素动员组外周血内皮祖细胞逐渐增加,于7 d达到高峰。高剂量促红细胞生成素动员组内皮祖细胞比例较低剂量组增加明显,促红细胞生成素动员组促进脱细胞猪皮移植区血管新生的效果明显强于对照组。结果可见,促红细胞生成素连续7 d腹腔注射能增加外周血内皮祖细胞的数量,在动员后第7天时达到高峰,效果成剂量依赖性,并能促进脱细胞猪皮移植区血管新生。 相似文献
995.
996.
Zhixin Chen Bao Xie Qinhua Zhu Qinghai Xia Songmin Jiang Ruoyu Cao Lihua Shi Dansi Qi Xiaokun Li Lin Cai 《International journal of medical sciences》2013,10(13):1868-1875
Objective: To investigate the expression and correlation of transforming growth factor-β1 (TGF-β1) and fibroblast growth factor receptor 4 (FGFR4) in human hepatocellular carcinoma (HCC) and the relationship with clinicopathological features and prognosis.Materials and methods: The expression of TGF-β1 and FGFR4 in 126 HCC samples was detected immunohistochemically. Combined with clinical postoperative follow-up data, the expression of TGF-β1 and FGFR4 in HCC and the relationship with the prognosis of patients were analyzed by statistically.Results: The positive expression rate of TGF-β1 was 84.1% (106/126) in tumors, and that in peritumoral liver tissues was 64.3% (81/126); the positive expression rate of FGFR4 in tumors was 74.6% (94/126) and that in peritumoral liver tissues was 57.1% (72/126). The expression of TGF-β1 and FGFR4 in the carcinoma tissues was significantly higher than that in peritumoral liver tissues (p < 0.05). Intratumoral TGF-β1 and FGFR4 expression was associated with TNM stage (p < 0.05). TGF-β1 and FGFR4 expression levels didn''t significantly correlate with other clinicopathological parameters, including age, sex, tumor size, serum AFP level, tumor differentiation, lymph node metastasis, etc. (p > 0.05). TGF-β1 expression was positively correlated with FGFR4 expression (r = 0.595, p < 0.05). Patients with positive FGFR4 or TGF-β1 expression had shorter overall survival compared with negative expression (p < 0.05).Conclusions: The expression of TGF-β1 and FGFR4 could make synergy on the occurrence and progression of HCC, and may be used as prognosis indicators for HCC patients. 相似文献
997.
Bi-layer collagen/microporous electrospun nanofiber scaffold improves the osteochondral regeneration
Shufang Zhang Longkun Chen Yangzi Jiang Youzhi Cai Guowei Xu Tong Tong Wei Zhang Linlin Wang Junfeng Ji Peihua Shi Hong Wei Ouyang 《Acta biomaterialia》2013,9(7):7236-7247
An optimal scaffold is crucial for osteochondral regeneration. Collagen and electrospun nanofibers have been demonstrated to facilitate cartilage and bone regeneration, respectively. However, the effect of combining collagen and electrospun nanofibers on osteochondral regeneration has yet to be evaluated. Here, we report that the combination of collagen and electrospun poly-l-lactic acid nanofibers synergistically promotes osteochondral regeneration. We first fabricated bi-layer microporous scaffold with collagen and electrospun poly-l-lactic acid nanofibers (COL-nanofiber). Mesenchymal stem cells were cultured on the bi-layer scaffold and their adhesion, proliferation and differentiation were examined. Moreover, osteochondral defects were created in rabbits and implanted with COL-nanofiber scaffold. Cartilage and subchondral bone regeneration were evaluated at 6 and 12 weeks after surgery. Compared with COL scaffold, cells on COL-nanofiber scaffold exhibited more robust osteogenic differentiation, indicated by higher expression levels of OCN and runx2 genes as well as the accumulation of calcium nodules. Furthermore, implantation of COL-nanofiber scaffold seeded with cells induced more rapid subchondral bone emergence, and better cartilage formation, which led to better functional repair of osteochondral defects as manifested by histological staining, biomechanical test and micro-computed tomography data. Our study underscores the potential of using the bi-layer microporous COL-nanofiber scaffold for the treatment of deep osteochondral defects. 相似文献
998.
动脉粥样硬化性脑梗塞患者载脂蛋白B基因的MspⅠ限制性片段长度多态性研究 总被引:1,自引:0,他引:1
为了解动脉粥样硬化性脑梗塞(atheroscleroticcerebralinfarction,ACI)与载脂蛋白代谢异常的关系,利用ApoBcDNA探针(LB1.5)检测了54名ACI患者和62名正常对照者的载脂蛋白B(ApoB)基因MspⅠ限制性片段长度多态性(RFLP)等位基因频率。结果显示,116份标本共出现2.35kb(M1)和2.60kb(M2)两条杂交片段。M2等位基因频率在ACI(0.157)和对照者(0.056)之间存在明显差异(χ2=7.17,P<0.01)。M2基因的检出和基因频率的获得为进一步揭示ApoB基因区域在ACI的脂类代谢中的作用提供了一个很好的遗传标记。还就不同基因型与血脂、脂蛋白水平的关系进行了讨论。 相似文献
999.
李幼平 《生物医学工程学杂志》1997,14(4):383-387
诱导供者特异性免疫耐受是最终克服移植排斥提高受者生存质量的有效途径之一。近年随着对树突状细胞发育成熟过程的认识步步深入,树突状细胞在移植排斥和移植耐受平衡中的双向调节作用引入注目。 相似文献
1000.
大鼠消化道神经激肽A的发育研究 总被引:3,自引:1,他引:3
应用免疫细胞化学PAP法系统研究了大鼠胚胎13天至成年食道及胃神经激肽A发生发育过程。结果如下:(1)在食道,直至出生前,即胚胎21天才于环肌层及粘膜肌层出现阳性膨体纤维,出生后,随幼鼠的生长发育相继在上皮内、纵肌层、肌间丛、粘膜下丛出现神经激肽A免疫反应阳性物,其纤维的密度、粗细和着色也逐渐增加,30天时已具备成年的分布特征,其发育主要在生后4周;(2)在胃,于胚胎14天,首先在肌间丛处呈现阳性 相似文献