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51.
目的 探讨体外分离培养结膜上皮细胞治疗翼状胬肉的方法.方法 将126例翼状胬肉患者(均为单眼患者)随机分为2组.治疗组58例,术前2周取其穹隆部结膜(1mm×1mm)剪成0.5mm×O.5mm大小后种植于羊膜上体外培养,术中逆行切除胬肉组织,再将培养好的结膜上皮植片移植于结膜创口,缝合固定.对照组68例,单纯切除翼状胬肉,暴露角巩膜缘.两组术后均行妥布霉素眼膏及滴眼液治疗,预防感染.结果 接种在羊膜上的结膜组织,8d左右融合成膜状,细胞为复层上皮细胞.植片3d后开始呈透明或半透明状,1周时可见新生血管长入,植片与周围结膜逐渐融合,2周左右植片与周围结膜完全融合.术后随访1~2年.治疗组复发2例(3.45%),对照组复发23例(33.82%),两组问复发率差异显著,有统计学意义(x2=16.3.P<0.01).所有患者眼球活动自如,未发生睑球粘连、疤痕增生等并发症.结论 体外分离培养结膜上皮细胞治疗翼状胬肉是一种理想的方法.  相似文献   
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The action of the cytostatic drugs (epirubicin and vincristine) in combination with the endogenous antiproliferative beta-hemoglobin fragment (33-39), valorphin, was studied in tumor (L929 and A549) cell cultures, primary culture of murine bone marrow cells and in murine model of breast carcinoma in vivo. Simultaneous application of 1 microM valorphin and 1 microM epirubicin, in vitro, did not result in an additive suppressive effect on cell culture growth. Additive effects were achieved with alternating applications of the peptide and the drugs, namely, 0.5 microM (but not 1 microM) epirubicin added 24 h prior to 1 microM valorphin; 1 microM valorphin added 48 h prior to 0.1 microM epirubicin, or 0.1 microM vincristine, or 0.05 microM vincristine, which resulted in 100% cell death in the both series with vincristine and up to 78% cell biomass reduction in the experiments with epirubicin. In the in vivo model (female BLRB mice with subcutaneously inoculated syngeneic mammary carcinoma), simultaneous treatment with 25 mg/m(2) epirubicin and 1 mg/kg valorphin resulted in 42% of tumor growth inhibition, as compared with the negative control group and 22% inhibition as compared with the epirubcin-treated group (at 20th day of treatment). Survival was significantly improved (69% compared to 39% in the group treated with epirubicin only) at day 26 after the treatment beginning.  相似文献   
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HIV-infected individuals frequently develop Mycobacterium tuberculosis (MTB) infection. Alveolar macrophages (AM) are the initial host defense against this organism. We measured MTB growth in AM from normal and HIV-infected subjects after in vitro exposure. Intracellular growth of MTB was reduced in AM from HIV-infected subjects compared with normal macrophages. This was confined to subjects with CD4 counts greater than 200/microl. Growth of avirulent mycobacteria in HIV macrophages was significantly less than virulent MTB. Because avirulent MTB is more sensitive to tumor necrosis factor-alpha (TNF-alpha), we examined the relationship between cytokine secretion and mycobacterial growth. Higher AM spontaneous TNF-alpha secretion was associated with reduced MTB growth in normal AM. This relationship was not seen in HIV-infected subjects, suggesting that other factors contributed to mycobacteria resistance. Mycobacteria-induced TNF-alpha secretion was inversely associated with growth in normal AM but not in HIV-infected subjects. Finally, binding and internalization of MTB was augmented in HIV macrophages compared with normal, demonstrating that reduced intracellular MTB growth was not due to impaired phagocytosis. In conclusion, the increased incidence of MTB infection in HIV-infected subjects does not appear to be due to a defect in macrophage innate immunity.  相似文献   
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The AutoCapture (AC) function of new pacemakers (PM) from St Jude Medical (SJM) was originally recommended for use with low polarization (LP) ventricular leads only.However, recent reports have encouraged the use of the AC function with various leads, including those lacking a special LP design. The objective of this study was to analyze the reliability and safety of the AC algorithm application with different types of pacing leads.The study group comprised 30 consecutive patients with AC PMs connected to three different types of non-LP leads. Ten patients with SJM LP leads served as the control group. The study protocol included a complete AC function test using four different pulse widths (PW). The pacing threshold was independently assessed by a manual/semiautomatic check. Erratic behavior of polarization measurements with increasing PWs was demonstrated in 43% (n = 13) of the study group. Invalid polarization measurements resulted in erroneous algorithm recommendation to apply AC function in 17% (n = 5) of the study patients. Subsequent AC function activation lead to incorrect threshold determination due to missed noncapture in three patients. AC function should be applied with caution with non-LP leads. "Off label" use of these leads may cause erroneous polarization signal measurements which, in some cases, may result in incorrect pacing threshold determination, rendering a potential risk to dependent patients.  相似文献   
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Membrane-type 1 matrix metalloproteinase (MT1-MMP) is an integral membrane proteinase that is frequently expressed in malignant cancer cells and has potent invasion-promoting activity. When expressed on the cell surface, MT1-MMP degrades the extracellular matrix (ECM) barrier adjacent to the cells to maintain the migration route to traverse the tissue. But MT1-MMP is not just an enzyme that degrades ECM. MT1-MMP also introduces limited cleavage into proteins at the cell-ECM interspaces and converts their functions. The target molecules are ECM components, cell adhesion molecules, and latent forms of MMPs. Through these processing events MT1-MMP modulates the migratory and invasive behavior of the cells.  相似文献   
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The clinical utility of the Behavioral Dyscontrol Scale (BDS) was compared to that of verbal fluency, the Trail Making Test, and the Stroop Color-Word Test, as well as measures of processing speed/cognitive efficiency and manual dexterity. The ability of these measures to classify 49 TBI patients into frontal versus nonfrontal and mild to moderate versus severe groups was examined. The results showed that the Fluid Intelligence Factor of the BDS improved classifications above and beyond traditional executive measures, but was particularly successful at classifying patients who sustained mild injuries. In contrast, traditional executive instruments were successful at lesion location classifications only among the patients with severe injuries. Severity classifications were successful both for traditional measures of processing speed/cognitive efficiency and for the Motor Programming Factor of the BDS, but only among patients with nonfrontal injuries. These results demonstrate that severity of injury may be an important moderator of tests' sensitivity to frontal lobe involvement.  相似文献   
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