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41.
Summary:To construct the antisense transforming growth factorβ1(TGFβ1)gene and investigatethe effect of TGFβ1 autocrine loop blockage on the proliferation of osteosarcoma cells.TGFβ1 cDNAwas cloned by RT-PCR from human osteosarcoma cells(MG-63)and inserted into pcDNA_3 to con-struct an antisense expression vector,which was dubbed pcDNA_3-TGFβ1(-).MTT was used to de-tect the proliferation of osteosarcoma cells transfected by antisense TGFβ1 gene.Our results showedthat the proliferation of the transfected osteosarcoma cells was suppressed markedly.It is concludedthat TGFβ1 autocrine loop blockage in osteosarcoma cells could inhibit cell proliferation,which mightbe helpful for gene therapy of osteosarcoma. 相似文献
42.
心导纳微分环,肺导纳微分环最大向量正常值及其临床意义 总被引:2,自引:0,他引:2
本文报道3-50岁214例心导纳微分环(CADL)和肺导纳微分环(PADL)最大向量振幅及方位正常值,结果随增龄变化振幅递减,方位递增,多数男>女,部分组间有差异。48例左向右分流先心病环体最大向量与肺动脉压之间呈平行关系,并探讨其临床意义。 相似文献
43.
赵毅 《中国医疗器械杂志》2005,29(6):456-457
来用锁相环IC CD4046设计的心率显示报警电路,用于数台老式监护仪的改造中,获得成功. 相似文献
44.
Alexandros Zafiropoulos Eva Andersson Elias Krambovitis Carl A. K. Borrebaeck 《Journal of immunological methods》1997,200(1-2):181-190
The use of in vitro immunization technology for the generation of human antigen-specific antibodies has essentially resulted in low affinity IgM antibodies, resembling an in vivo primary immune response. We now describe a detailed reproducible protocol for a two-step in vitro immunization, which yields isotype switched, antigen-specific human antibodies. The immunizing antigen was a 30aa synthetic peptide, containing both a B (15aa V3 peptide of the HIV-1) and a T helper cell epitope (15aa peptide from tetanus toxin). The immunization protocol includes: (i) a selection procedure of donors with a memory T cell response against tetatus toxoid; (ii) immunization of mature naive peripheral B lymphocytes in two distinct phases, involving a primary and a secondary step. None of the donors which were examined after primary 7immunization showed at any time an IgG anti-V3 specific antibody response, while all the donors showed an IgM response. After the secondary immunization step, anti-V3 antibodies of both IgM and IgG isotypes were detected. The switch frequency event was high among the tested donors (5/8). 相似文献
45.
寒冷干燥地区平时火器伤的早期处理 总被引:3,自引:3,他引:0
目的 探讨寒冷干燥地区平时火器伤伤情特点与早期救治方法。方法 对 1991年 1月— 2 0 0 2年 12月间 40例火器伤病人的临床救治进行回顾分析。结果 2 4例枪伤中 ,2 0例一期缝合伤口 ,均一期愈合 ,另外 4例只清创未一期缝合的伤口 ,3例愈合 ,1例感染 ;4例骨折内固定均愈合良好 ,无骨髓炎发生。 16例炸伤病人局部软组织损伤及污染比枪弹伤重 ,14例一期缝合伤口中 ,10例一期愈合 ,4例感染 ,骨折内固定 2例 ,均愈合良好 ,无骨髓炎发生。结论 寒冷干燥地区火器伤早期伤道清创时限可适当延长 ,在平时火器伤的救治中 ,对软组织条件较好的创面 ,早期清创后可一期闭合伤口和骨折内固定 ,这样可减少感染和伤残 ,促进康复 相似文献
46.
选择某电子对抗团战士和某坦克旅战士共64人,分别在高温、高湿等因素作用下连续作业1h(摩托小时),观察战士体内激素及电解质的变化情况。结果表明:两部队战士的心钠素、皮质醇、醛固酮水平作业前后有非常显著性以上的差异;血清K~+、Ca~(2+)浓度降低,Na~+浓度升高。以上结果表明:高温环境对战士体内激素水平影响显著,机体出现应激性改变。 相似文献
47.
Effects of nilvadipine on the low- and high-voltage activated Ca2+ currents (LVA and HVA ICa, respectively) were compared with other organic Ca2+ antagonists in acutely dissociated rat hippocampal CA1 pyramidal neurons. The inhibitory effects of nilvadipine, amlodipine and flunarizine on LVA ICa were concentration- and use-dependent. The apparent half-maximum inhibitory concentrations (IC50s) at every 1- and 30-s stimulation were 6.3×10−7 M and 1.8×10−6 M for flunarizine, 1.9×10−6 M and 7.6×10−6 M for nilvadipine, and 4.0×10−6 M and 8.0×10−6 M for amlodipine, respectively. Thus, the strength of the use-dependence was in the sequence of nilvadipine>flunarizine>amlodipine. Nilvadipine also inhibited the HVA ICa in a concentration-dependent manner with an IC50 of 1.5×10−7 M. The hippocampal CA1 neurons were observed to have five pharmacologically distinct HVA Ca2+ channel subtypes consisting of L-, N-, P-, Q- and R-types. Nilvadipine selectively inhibited the L-type Ca2+ channel current which comprised 34% of the total HVA ICa. On the other hand, amlodipine non-selectively inhibited the HVA Ca2+ channel subtypes. These results suggest that the inhibitory effect of nilvadipine on the neuronal Ca2+ influx through both LVA and HVA L-type Ca2+ channels, in combination with the cerebral vasodilatory action, may prevent neuronal damage during ischemia. 相似文献
48.
H. Kanno T. Kuwabara M. Shinonaga C. C. Chang Y. Tanaka Y. Sugio H. Morita H. Yasumitsu M. Umeda Y. Nagashima 《Acta neuropathologica》1989,79(1):30-36
Summary A human glioma cell line (YKG1), which was positively identified for glial fibrillary acidic (GFA) and S-100 proteins, was established from a surgical specimen of a patient with glioblastoma. Chromosome analysis of the cells revealed a homogeneously staining region (HSR) on a marker chromosome. The assay for transforming growth factors (TGFs) in the conditioned medium of the cell line revealed that it contained high levels of - and -type TGFs, which might regulate the growth of glioblastoma and influence on the peritumoral tissues. 相似文献
49.
Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2 总被引:4,自引:0,他引:4
Hu YW Rocheleau L Larke B Chui L Lee B Ma M Liu S Omlin T Pelchat M Brown EG 《Virology》2005,332(2):538-549
Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns. 相似文献
50.
Breast cancer micrometastases: Different interactions of carcinoma cells with normal and cancer patients' bone marrow stromata 总被引:6,自引:1,他引:6
Nicola MH Bizon R Machado JJ Sollero T Rodarte RS Nobre JS Magalhães MM Takiya CM Borojevic R 《Clinical & experimental metastasis》2003,20(5):471-479
The apparently dormant breast cancer micrometastases in haemopoietic marrow are correlated with distant metastatic carcinoma
dissemination. We studied in vitro interactions of carcinoma cells with adjacent stromata, using connective tissue cell cultures from breast and bone marrow
samples of normal donors, comparing them to the pericancerous breast tissue and bone marrows of 12 selected patients with
invasive breast carcinomas. Cancer cells were detected by immunocytochemistry and RT-PCR in all the bone marrows and in most
blood samples of the studied patients. We monitored the growth and interaction of carcinoma MCF-7 cells with the stromata.
The normal breast stroma sustained typical massive cancer growth. The pericancerous breast stroma induced the invasive mesenchymal
pattern of growth. Normal bone marrow stroma induced the same conversion and was highly adhesive, retaining the cells in the
stroma, but carcinoma patients' bone marrow stromata underwent low adhesive interactions with cancer cells, releasing them
potentially into the circulation. The semi-quantitative RT-PCR indicated an enhanced expression of the hepatocyte growth factor
and its receptor c-met in breast and bone marrow stromata of cancer patients. The input of cancer cells into the normal bone marrow may induce modifications
of the local microenvironment, favourable for growth and release of carcinoma cells into the systemic circulation, which correlate
with the poor prognosis of patients with bone marrow micrometastases.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献