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991.
992.
Fang Q  An N  Wu XY  Liu QL  Feng SH 《中华医学杂志》2004,84(8):667-670
目的 产前诊断多胎妊娠的合子性质并检测染色体21三体、18三体、13三体和性染色体三体异常。方法 选择因各种指征产前诊断或拟行选择性减胎的多胎妊娠17例38个胎儿,抽取羊水或脐血及其父母外周血,采用短串联重复序列聚合酶链反应(short tandem repeat and polymerase chain reaction,STR-PCR)技术检查胎儿的合子性质,同时检查有无上述染色体异常;选择18个单胎妊娠产前诊断胎儿及其父母的样本,作为染色体三体检测的对照组。结果 7例体外受精胚胎移植的多胎妊娠均为多合子;7例伴有1胎畸形的多胎妊娠,仅1例为双合子双胎。本组多胎妊娠胎儿未发现有上述染色体三体异常。对4例多合子多胎于妊娠中期行减胎术,预后良好。结论 STR-PCR技术可快速、准确鉴定多胎合子性质,同时诊断胎儿染色体三体,有助于多胎妊娠的产前监测;当出现1胎畸形和拟行减胎术时,有助于选择处理方式。  相似文献   
993.
Kurarinone, a lavandulyl flavanone, was isolated from a polyphenolic extract of the roots of Sophora flavescens using fractionation guided by estrogenic activity, which was determined by recombinant yeast and Ishikawa Var-I bioassays. Kurarinone showed weak estrogenic activity both in the yeast screen and in the Ishikawa Var-I assay with EC(50) values of 4.6 and 1.66 microM, respectively. Furthermore, kurarinone was found to have potent cytotoxic activity (IC(50) value = 22.2 microM) against human MCF-7/6 breast cancer cells in the sulforhodamine-B assay.  相似文献   
994.
CD95/Fas is a cell surface protein that belongs to the tumor necrosis factor receptor family. Signals through CD95/Fas are able to induce apoptosis in sensitive cells. Therefore, modalities to regulate the CD95/Fas expression level in tumor cells are called for. In the present study, we show that sublethal doses of arsenic trioxide (As2O3) sensitized CD95/Fas-induced apoptosis in human cervical cancer cells, and the sensitizing effects resulted from As2O3-mediated increase in the expression of the CD95/Fas. N-acetyl-L-cysteine, a specific scavenger of reactive oxygen species, abrogated As2O3-induced upregulation of CD95/Fas and enhancement of CD95/Fas-mediated apoptosis. Furthermore, inhibition of NF-kappaB by transient transfection of IkappaBalpha supersurppessor blocked the increase of CD95/Fas expression following As2O2 treatment. Antisense oligonucleotide of CD95/Fas and ZB4, an antibody that blocks the binding of CD95/Fas ligand to CD95/Fas, reduced the amount of As2O3-sensitized CD95/Fas-induced apoptosis, demonstrating the specificity of CD95/Fas-binding ligands in the As2O3-sensitized CD95/Fas-induced apoptosis. These findings demonstrate that sensitization of human cervical cancer cells to CD95/Fas-mediated apoptosis by As2O3 can be partly due to induction of ROS and subsequent upregulation of CD95/Fas gene expression by NF-kappaB activation.  相似文献   
995.
In the present study, the P(2)X(7) receptor expression in the gerbil hippocampus and GABA-mediated responses of its expression was investigated in order to identify the roles of the P(2)X(7) receptor on seizure activity and recovery mechanisms. P(2)X(7) receptor immunoreactivity in seizure-resistant (SR) gerbils was similar to that in pre-seizure group of seizure-sensitive (SS) gerbils. The administration of baclofen, a GABA(B) receptor agonist, P(2)X(7) receptor immunoreactivity was decreased in the mossy fiber, compared with that of non-treated gerbils, whereas treatment with phaclofen, a GABA(B) receptor antagonist, elevated P(2)X(7) receptor expression. Neither the treatments with GABA(A) receptor agonist nor antagonist affected P(2)X(7) receptor expression in the hippocampus. These findings suggest that altered P(2)X(7) receptor expression may not be involved in the epileptogenesis or seizure activity in gerbils, and presynaptic GABA(B) receptor-mediated actions may be closely related with the regulation of P(2)X(7) receptor expression in the gerbil hippocampus.  相似文献   
996.
997.
This experiment tested the effect of an injection of orexin A into the diagonal band of Broca on the sympathetic activity and body temperature. Concentration of glycerol into white fat of lumbar region, firing rates of sympathetic nerves to interscapular brown adipose tissue (IBAT), IBAT and colonic temperatures, and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats for 30 min before and 150 min after injections of orexin A (0.4 and 0.7 nmol) into the diagonal band of Broca. The same variables were monitored in control rats with an injection of saline. The results show that orexin A increases glycerol concentration, sympathetic firing rate, IBAT and colonic temperatures, and heart rate. The saline injection did not induce any modification. These findings suggest that the diagonal band of Broca is a cerebral structure involved in the induction of the hyperthermia due to orexin A.  相似文献   
998.
WooKiEum (WKE) has been used for the purpose of the development of increased immune-system strength in Korea. In the present study, we examined the anti-immobility effect of WKE on the forced swimming test (FST), and then measured blood biochemical parameters related to fatigue: glucose (Glc), blood urea nitrogen (BUN), lactic dehydrogenase (LDH), creatinine, and total protein (TP). WKE (0.1, 1 g/kg) was administered orally to mice for 7 d. After 2 d, the immobility time was decreased in the WKE-administered group. After 7 d, the immobility time was significantly decreased in the WKE-administered group (64.6+/-9.0 s for 0.1 g/kg) in comparison with the control group (101.3+/-32.7 s). In addition, amount of Glc in the blood serum was increased, whereas the contents of BUN, LDH and TP decreased in the WKE-administered group. Next, we investigated the effect of WKE on the production of cytokines in a human T-cell line, MOLT-4 cells and mouse peritoneal macrophages. WKE (1 mg/ml) significantly increased interferon (IFN)-gamma and TNF-alpha production compared with the media control (about 2.2-fold for IFN-gamma, about 1.7-fold for TNF-alpha, p<0.05) after 24 h. WKE increased the protein expression of IFN-gamma in MOLT-4 cells. These results suggest that WKE may be useful in immune function improvement.  相似文献   
999.
The carpophores of Paecilomyces tenuipes are known in the Orient for their strong antitumor activity. In continuation of our study on acetoxyscirpendiol (ASD, 4beta-acetoxyscirpene-3alpha,15-diol) as a cytotoxic component from this fungus, we report particularly on the mode of action of ASD in inducing apoptosis in human MOLT-4, THP-1 and Jurkat T cell leukaemia in vitro. The antiproliferative effects of ASD seem attributable to its induction of apoptosis in the cells, as it blocked the cell cycle, induced hypodiploidity and bound annexin V and also cleaved poly-(ADP-ribose) polymerase (PARP) in these cell lines. The 50% inhibitory concentrations (IC50) of ASD on MOLT-4, THP-1 and Jurkat T cells were found to be 60, 85 and 60 ng/ml, respectively. ASD arrested the cell cycle at the G1/S transition and showed hypodiploidity due to the accumulation of sub-G0 population. Annexin V binding was increased in the presence of ASD in the MOLT-4 cell line in a time-dependent manner. ASD and three of its derivatives also induced cleavage of PARP in both MOLT-4 and Jurkat T cell lines. From these data, it is suggested that ASD exerts its cytotoxic activity by inducing apoptosis in leukaemia cell lines in vitro.  相似文献   
1000.
An J  Sun JY  Yuan Q  Tian HY  Qiu WL  Guo W  Zhao FK 《Oral oncology》2004,40(4):400-408
Metastasis is the most insidious and life threatening aspect of cancers. However little is known about the molecular mechanisms of tumor metastasis. A poorly metastatic Acc-2 cell line and highly metastatic Acc-M cell line were selected as an experimental model to study on metastatic mechanisms and antimetastatic procedures. In the present study, two-dimensional gel electrophoresis and mass spectrometry are combined to approach the protein profiles associated with tumor metastasis between Acc-2 and Acc-M cell lines. Image analysis of silver stained 2-dimensional gels revealed that 12 protein spots showed significantly quantitative and qualitative variations and mass spectrometry is utilized to further identify these spots. Of the identified proteins, transketolase, Dim1p, v-Ha-ras oncogene, type I collagen pro alpha, tumor necrosis factor (ligand) superfamily member 4, and pirin etc, have shown associations with distinct aspect of tumor metastasis to some extent. The dissimilar expression patterns of these 12 spots indicate the different roles they may play involved in tumor metastasis.  相似文献   
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