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991.
We report a 61-year-old right-handed man developing disturbance of memory after a discrete thalamic infarction. Neuropsychological assessment revealed deficits in memory with retrograde and anterograde components, especially for verbal material. Brain MRI showed a left anterior thalamic infarction with normal angiographic findings. Despite the small lesion in the thalamus, he showed prolonged memory disturbance and a Brain SPECT image revealed decreased uptake in the ipsilateral fronto-temporo-parietal cortex and contralateral cerebellum. This diaschisis, a phenomenon caused by disconnection of the neural pathway helped us to evaluate the functional state of the patient and this imaging technique was valuable for obtaining to get more information for the evaluation of the neurological state and neuronal connections. In conclusion our findings correspond well with the understanding of amnesia as a disconnection syndrome because of the evidence of diaschisis on the Brain SPECT image.  相似文献   
992.
Feng Z  Hong J  Qi Q  Han Y  Wilson B  Iadarola M  Tiao N  Bing G 《Neuroscience letters》2000,296(2-3):129-132
C-Fos and the Fos-related antigens (FRA) are induced by various stimuli. A novel 35-37 kDa FRA was induced much longer after the treatment using kainic acid (KA) and may be very important for neuronal survival after brain damage. To identify this long-term FRA, we have constructed a cDNA library derived from hippocampus after KA treatment and screened it with an antibody highly conserved M-peptide region of FRAs. One gene, MP13, was cloned with a 1662 bp open reading frame and coded for a 554-amino acid protein. MP13 has a leucine zipper region, a glutamine repeat region, and has high similarity to the activator of the small guanosine triphosphate (GTP)ase Rab5. Gel retardation analysis revealed that MP13 functions as a GTP regulation related factor.  相似文献   
993.
向大白鼠脊髓的颈、腰膨大和胸髓右侧半分别注入HRP或WGA—HRP,研究了脊髓向延髓外侧网状核的投射。 1.双侧的三叉神经下亚核同时接受颈、胸和腰髓来的投射。 2.大白鼠脊髓主要投射于外侧网状核的尾侧半,有一定的体部定位关系。颈髓投射于双侧大细胞亚核的外侧2/3及与共相邻接的一部分小细胞亚核内,以同侧投射为主。胸髓投射于双侧的大细胞亚核的内侧2/3和与之相邻接的一部分小细胞亚核内,两侧无明显差別。腰髓投射于双侧小细胞亚核和与之相邻接的部分大细胞亚核内,以对侧投射为主。它们相互间有部分重叠。 3.颈、胸和腰髓内外侧网状核投射的神经元位于从背角至腹角的灰质内,越边投射的神经元比不越边投射的神经元位置更靠腹侧。  相似文献   
994.
目的 研究二十碳五烯酸(EPA)是否协同视黄酸(RA)影响HL-60细胞的凋亡及相应分子机制。方法 流式细胞仪(FCM)检测细胞周期相分布以测定细胞增殖和凋亡功能;Western blot法分析bcl-2和caspase—3表达。结果 与单独应用相比,EPA和RA联合应用可增强HL-60细胞的调亡效应,以及下调节bcl—2和增强caspase-3基因表达。结论 EPA和RA联合应用对HL-60细胞凋亡的增强效应,可能与它们增强caspase-3和降低bcl—2基因表达相关。  相似文献   
995.
996.
AIM: To evaluate the relationship between IL-18 levels in urine and parameters of renal pathological changes in patients with lupus nephritis (LN). METHODS: IL-18 levels in morning free urine and 24-hour's urine in 19 normal persons and 55 patients with LN were measured by ELISA. The correlation between IL-18 levels and parameters of renal pathological changes, namely activity index (AI) and chronicity index (CI), were analyzed by liner correlation analysis method. RESULTS: IL-18 levels in morning free urine and 24-hour's urine in LN group were elevated significantly compared with control group. In both groups IL-18 levels in morning free urine were (247.1+/-317.5) ng/L and (20.3+/-14.5) ng/L, respectively, P<0.001; those in 24-hour's urine were (192.1+/-170.1) ng/d and (21.0+/-3.8) ng/d, respectively, (P<0.001). There was close positive correlation between IL-18 levels in morning free urine and 24-hour's urine and LN patient's AI (for morning free urine: r=0.602, P<0.001; for 24-hour's urine: r=0.461, P<0.005) but there was no correlation between IL-18 levels in morning urine and 24-hour's urine and CI (P>0.05). Patients with LN were divided into three groups (high, moderate and low) according to AI value. There was distinct difference of IL-18 levels in urine among the three groups: IL-18 levels in morning urine were (69.2+/-82.7) ng/L, (193.5+/-106.1) ng/L and (580.7+/-453.1) ng/L, respectively, (P<0.001); those in 24-hour's urine were (103.5+/-141.4) ng/d, (188.8+/-124.0) ng/d and (333.1+/-183.2) ng/d, respectively. CONCLUSION: It is very simple and convenient to detect IL-18 levels in morning free urine, so it is a good method for evaluating renal pathological activity of LN.  相似文献   
997.
Liver is the primary source for collagen XVIII, the precursor of angiogenesis inhibitor, endostatin. However, the role of endostatin/collagen XVIII expression during liver carcinogenesis remains elusive. Therefore, we studied its expression in five hepatoma cell lines and 105 hepatocellular carcinoma specimens. The poorly differentiated hepatoma cell lines exhibited increased endostatin/collagen XVIII levels compared with the well-differentiated ones. In hepatoma tissues, endostatin/collagen XVIII expression was detected in various types of liver cells and was significantly stronger in adjacent nontumor tissues than that in tumors (P<0.001). Endostatin/collagen XVIII expression in nontumor tissues correlated with tumor stages (P=0.014) and expression of vascular endothelial growth factor (P=0.007), but not the stages of hepatic fibrosis (P>0.05). Kaplan-Meier analysis showed that patients with higher endostatin/collagen XVIII expression had significantly shorter overall survival (P=0.011) and disease-free survival (P=0.0034). Moreover, endostatin/collagen XVIII level was an independent prognostic factor for tumor recurrence (P=0.034) by multivariate analysis. In conclusion, increased endostatin/collagen XVIII expression correlated with hepatoma progression and predicted poor prognosis for patients with hepatocellular carcinoma.  相似文献   
998.
Decidualization is a critical step during embryo implantation that is characterized by the differentiation of endometrial stromal cells (ESC) into decidua cells. However, the mechanism of differentiation remains largely unknown. Previously, it has been shown that the null function of homeo box A10 (HOXA10) causes defects in both implantation and decidualization, suggesting that the HOXA10 signalling pathway is likely to be involved in uterine decidualization. In the present study, we determined the expression and subcellular distribution of HOXA10 and its downstream molecule, p57, in ESC during in vitro decidualization induced by a combination of 8-bromo-cAMP and medroxyprogesterone acetate. We demonstrated that the HOXA10 was down-regulated while in contrast, p57 was up-regulated in the process of decidualization. Immunocytochemistry and transient expression of the HOXA10 tagged with green fluorescence protein revealed that there were no differences in the HOXA10 subcellular localization between the induced and non-induced ESC. Our results suggest that the down-regulation of HOXA10 may contribute to increased p57 and that up-regulation of p57 likely plays an important role in ESC differentiation in the process of decidualization. The progesterone receptor pathway may participate in promoting ESC to exit the cell cycle and enter differentiation.  相似文献   
999.
Plasmids containing the inosine monophosphate dehydrogenase gene CaIMH3 from Candida albicans strain ATCC 32354 transform their host to resistance against mycophenolic acid (MPA). The transformants maintain the plasmids at a high copy number (20–40 per cell) and express the CaIMH3 gene at very high levels relative to untransformed controls. The plasmid copy number can be controlled by the concentration of MPA in the media. The transformation procedure is reproducible and the efficiency of transformation is high, up to 15,000 per microgram. Unrearranged plasmids are readily recovered by transforming total DNA from transformants back into Escherichia coli. C. albicans genes cloned into the plasmid are expressed at elevated levels relative to untransformed controls. A derivative vector containing the CaMAL2 promoter and termination sequences expresses the CaERG11 ORF at high levels and confers moderate resistance to fluconazole. These shuttle vectors should facilitate global genomics approaches in C. albicans that have been hampered by its diploid genome.  相似文献   
1000.
目的:探讨乳腺癌组织层粘连蛋白受体(LN-R)、Ⅳ型胶原(Col Ⅳ)、间质微血管密度与乳腺癌淋巴结转移的关系。方法:应用免疫组织化学S-P方法标记82例乳腺癌组织中LN-R、Col Ⅳ、FⅧRAg,并在第Ⅷ因子相关抗原(FⅧRAg)标记切片上计算微血管密度(MVD)。结果:LN-R表达强度及MVD的高低在乳腺癌有淋巴结转移组和无淋巴结转移组间有差异;ColⅣ在两组间无差异。结论:乳腺癌间质微血管密度增加及LN-R表达增强可作为预测肿瘤转移及判断预后的指标。  相似文献   
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