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991.
超声手术刀组织切割的实验研究 总被引:1,自引:0,他引:1
用国产超声手术刀,在大白兔活体上进行切割实验.并与普通手术刀和高频电刀进行了比较.结果显示超声手术刀的组织切割速度和切缘整齐情况不及普通手术刀,但有一定的止血功能,组织损伤不如高额电刀大,也不引起肌肉收缩,无组织烧焦气味;术后切缘愈合良好.认为超声手术刀更适合于肝、脾等实质性组织的切割.如在操作柄、刀具、仪器性能等方面能进一步改进,应用效果会更好。 相似文献
992.
993.
抗T细胞单克隆抗体对再生障碍性贫血患者TNF和IL—2水平的影响 总被引:2,自引:0,他引:2
为探讨抗T淋巴细胞克隆抗体对再生障碍性贫血患者免疫功能的调节作用,采用放射免疫检测25例AA患者McAb-T治疗前后血清肿瘤坏死因子和白细胞介素-2(IL-2)水平及其中10例周围血单个核细胞体外诱生TNF和IL-2水平的变化。 相似文献
994.
Jin Y Kim HP Ifedigbo E Lau LF Choi AM 《American journal of respiratory cell and molecular biology》2005,33(3):297-302
We have used gene expression profiling approaches to identify new molecular targets in various models of lung injury and human lung diseases. Among the many genes that are significantly induced in these studies, cysteine-rich61 (Cyr61) consistently ranks as one of the most significant genes. Here, we use the well-established model of hyperoxia to better understand the function of Cyr61 in acute lung injury. Cyr61, a stress-related immediate-early response gene, has known diverse functions involving angiogenesis, tumorigenesis, and wound repair. It belongs to the newly discovered "CCN" family containing six growth and regulatory factors. We showed that hyperoxia induces Cyr61 expression in a variety of pulmonary cells and in lung tissue in vivo. Loss of function studies, by suppressing Cyr61 expression by siRNA, accelerated lung epithelial cell death after hyperoxia. Gain of function studies, by overexpressing Cyr61, significantly conferred increased resistance to hyperoxia-induced cell death. Moreover, cells overexpressing Cyr61 induce Akt activation. Inhibition of Akt by siRNA abrogated the protective effects of Cyr61-overexpressing cells in response to hyperoxia. Taken together, our data demonstrate that Cyr61 expression provides cytoprotection in hyperoxia-induced pulmonary epithelial cell death and that this effect was in part mediated via the Akt signaling pathway. 相似文献
995.
Phenotypically different cells with heterogeneous nuclear ribonucleoprotein A2/B1 overexpression show similar genetic alterations 总被引:11,自引:0,他引:11
Man YG Martinez A Avis IM Hong SH Cuttitta F Venzon DJ Mulshine JL 《American journal of respiratory cell and molecular biology》2000,23(5):636-645
Immunocytochemical studies have revealed that overexpression of heterogeneous nuclear ribonucleoprotein (hnRNP) A2/ B1 in exfoliated epithelial cells is a potentially useful marker of early lung cancer. This study analyzed the correlation of hnRNP A2/B1 expression with molecular alterations in phenotypically different epithelial cells of paraffin-embedded pulmonary tissues. Sections from 20 human subjects were analyzed immunohistochemically for expression of hnRNP A2/B1. Normal-appearing, hyperplastic, and malignant epithelial cells with and without hnRNP A2/B1 expression (n = 78) were microdissected and assessed for microsatellite alterations (MA) and loss of heterozygosity (LOH) (n = 14 markers) as well as for clonality. Results showed that (1) hnRNP A2/B1 immunoreactive cells contained a significantly higher frequency of MA and LOH than did comparable cells that lacked detectable hnRNP A2/B1; (2) over 80% of MA and LOH seen in hnRNP A2/B1 immunoreactive normal-appearing and hyperplastic cells persisted in malignant cells; (3) preliminary analysis of methylation status of the androgen receptor gene in non-neoplastic cells was suggestive of hnRNP A2/B1-expressing cells being of clonal origin; and (4) cells with cytoplasmic hnRNP A2/B1 immunoreactivity had a 3-fold higher frequency of MA and LOH than did cells with nuclear hnRNP A2/B1 immunoreactivity. These findings suggest that phenotypically different respiratory epithelial cells with hnRNP A2/B1 overexpression might be clonally derived, and that the subcellular localization of hnRNP A2/B1 might be an important factor associated with tumor progression. 相似文献
996.
997.
Laser surface modification of poly(epsilon-caprolactone) (PCL) membrane for tissue engineering applications 总被引:2,自引:0,他引:2
Ultra-thin polycaprolactone (PCL) produced by bi-axial stretching was previously shown to have significant advantage for membrane tissue engineering. However, the permeability of the membrane needs to be enhanced. In this study, ablation experiments using femtosecond laser and excimer laser were carried out to modify the PCL surface. The use of the femtosecond laser produces neat drilled-through holes while the excimer laser is employed to produce blind-holes on the membrane. The modified surface of the membrane was studied and analyzed for different laser parameters (such as pulse energy and pulse repetition rate and characterized using several techniques that include optical microscopy, scanning electron microscopy and water contact angle measurements). Results showed that the morphological surface changes with different laser parameters, and the water contact angle decreases as the surface of the membrane is modified. The decrease in water contact angle suggests that surface of the membrane had become more hydrophilic than the non-laser treated membrane. The present study demonstrated that laser surface modification on the PCL can be achieved with high degree of success and precision. This paved the way for further enhancement in membrane tissue engineering. 相似文献
998.
999.
Chang KH Kim JM Kim HY Song YG Choi YH Park YS Cho JH Hong SK 《Yonsei medical journal》2000,41(1):112-118
Interleukin 15 (IL-15) is an important regulatory cytokine in cellular immunity. In vitro replacement of IL-15 has been shown to enhance immunity in Human immunodeficiency virus type 1 (HIV-1) infected lymphocytes. We evaluated the effect of IL-15 on the survival of peripheral blood mononuclear cells of HIV patients by examining in vitro lymphocyte apoptosis, and correlated the process with Bcl-2 and Fas gene regulation. Peripheral blood mononuclear cells (PBMC) from 21 HIV-infected adults and 24 HIV-seronegative healthy individuals were isolated and cultured to determine the effect of escalating doses of IL-15 (0, 1, 10, 100, 1000 ng/mL) on apoptosis. Lymphocyte proliferation assay with (3H) TdR was measured and Bcl-2 and Fas gene regulation was observed. The results were as follows: 1) IL-15 reduced culture induced lymphocyte apoptosis in HIV patients in a dose dependent manner, and reached a plateau level at a concentration of 100 ng/ml; 2) IL-15 significantly reduced the level of apoptosis after 3 days (14%) and 5 days (15%) of culture in HIV patients, while no difference was observed in HIV (-) donors; 3) The percentage of viable cells among the total number of lymphocytes was significantly enhanced by 25% in HIV patients with IL-15; 4) Bcl-2 expression was decreased in HIV patients (53.9 +/- 12.3%) compared to HIV (-) donors (93.0 +/- 3.7%), and IL-15 increased Bcl-2 expression by 21.2 +/- 5.2% in HIV patients; 5) Fas expression was increased in HIV patients (70.2 +/- 4.6%) compared to HIV (-) donors (32.4 +/- 4.3%), and IL-15 increased Fas expression by 8.4 +/- 1.2% in HIV (-) donors. Our findings indicate that IL-15 may influence immunologic abnormalities in HIV infection, particularly its ability to prevent apoptosis of lymphocytes by suppressing the down-modulation of Bcl-2. This may provide an experimental basis for IL-15 immunotherapy. 相似文献
1000.
Kim YM Lee KK Oh HS Park SK Won JH Hong DS Park HS Park JS Lee DW 《Journal of Korean medical science》2000,15(2):243-246
While pleural effusion in multiple myeloma is relatively infrequent, myelomatous pleural effusion is extremely rare. We experienced a 61-year-old woman with IgD-lambda multiple myeloma and pleural effusion. The diagnosis was made originally by pleural biopsy, pleural fluid cytology and immunoelectropheresis of pleural fluid. Transient improvement of the pleural effusion was observed after administration of combination chemotherapy of vincristine, melphalan, cyclophosphamide, prednisone (VMCP)/vincristine, cyclophosphamide, adriamycin, prednisone (VCAP). Two months later, myelomatous pleural effusion recurred and no response to salvage therapy was observed. We reviewed the clinical feature of this case and literature concerning myelomatous pleural effusion. 相似文献