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The endometrial epidermal growth factor (EGF) profile is an indicator of uterine function and fertility in cattle. The present study aimed to investigate the effects of heat stress on the endometrial EGF profile and fertility in lactating Holstein cows. The endometrial EGF profiles of 365 cows in the Hokkaido and Kyushu regions were examined between June and September (heat stress period, n = 211) and between October and January (control period, n = 154). EGF profiles were investigated using uterine endometrial tissues obtained by biopsy 3 days after estrus (Day 3). The proportion of cows with an altered EGF profile was higher between June and September than between October and January (41.2 vs. 16.2%, P < 0.05). The effects of rectal temperature on Days 0 and 3 on the endometrial EGF profile were also assessed in cows (n = 79) between June and September in the Kyushu region. A single embryo was transferred to cow on Day 7 to evaluate fertility (n = 67). Regardless of the rectal temperature on Day 3, the proportion of cows with an altered EGF profile was higher (64.1 vs. 30.0%, P < 0.05) and the pregnancy rate after embryo transfer (ET) was lower (26.7 vs. 51.4%, P < 0.05) in cows with a rectal temperature ≥ 39.5°C on Day 0 than in cows with a rectal temperature < 39.5°C on Day 0. The present results indicate that alterations in the endometrial EGF profile induced by an elevated body temperature on Day 0 contributed to reductions in fertility in lactating dairy cows during the heat stress period.  相似文献   
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AIM: To investigate the relationship between the expression of estrogen receptor α36 (ER-α36) and the invasion of gastric cancer cells. METHODS: SGC7901 cells were treated with 17β-estradiol at high or low concentration. The invasion of gastric cancer cells and the expression of ER-α36 were detected. The SGC7901 cells with the characteristics of stable low expression and high expression of ER-α36 were constructed. The invasion ability and microRNA sequences were determined in above-mentioned recombinant cells. RESULTS: The decreased invasion ability and ER-α36 expression were detected in SGC7901 cells treated with low concentration of 17β-estradiol. The situation was the opposite in the cells treated with high concentration of 17β-estradiol. The expression of miR-143 was significantly decreased in the SGC7901 cells with stable high expression of ER-α36 and was increased in the SGC7901 cells with stable low expression of ER-α36. CONCLUSION: The expression of ER-α36 is positively related to the invasion of gastric cancer cells. It is possible that miR-143 plays an important role in the regulation of gastric cancer invasion.  相似文献   
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AIM:To determine whether suspension culture medium without insulin can be used to feed breast cancer tumorsphere, or not. METHODS:MCF7 cells were used to build tumorsphere. The morphological changes, CD44+ CD24- expression, aldehyde dehydrogenase 1 (ALDH1) expression and multiple division ability were measured to identify the breast cancer stem cells and to detect the function of 17β-estradiol (E2β) in tumorsphere of MCF7 cells. RESULTS:The tumorshere, each containing 30 to 60 cells, was obtained by the method of insulin-removal suspension culture. These cells were cytokeratin 18 and CD10 proteins positive, and the number of CD44+ CD24- cells and ALDH1 protein expression were significantly higher than the adherent cultured cells (P<0.05). Using 10-10 mol/L E2β to treat the tumorshere for 7 d, the tumor cell number and volume were significantly increased. Using 10-10 mol/L E2β to treat the tumorshere for 24 h, the CD44+ CD24-cells and ALDH1 protein expression were significantly higher than those in non-treatment group (P<0.05). CONCLUSION: Suspension culture medium without insulin can be used to feed breast cancer tumorsphere. These tumorsphere could be used as a model to determine the function of E2β in breast cancer stem cell research.  相似文献   
25.
AIM: To investigate the expression and significance of RhoC and Ki-67 in human esophageal squamous cell carcinoma (ESCC) tissues.METHODS: The expression of RhoC and Ki-67 was detected in 52 specimens of ESCC by the method of immunohistochemistry. The clinicopathological features were also analyzed.RESULTS: The expression of RhoC was detected in 32 of the total 52 (61.5%) cases of human ESCC tissues, significantly higher than that in the adjacent histologically normal epithelium, which was only in 11 of 37 cases (29.7%, P<0.05). RhoC expression was closely correlated with clinical tumor-node-metastasis (TNM) stage (P<0.05) and lymph node metastasis (P<0.05) in ESCC. The over-expression of RhoC was positively correlated with Ki-67 in ESCC (r=0.322, P<0.05).CONCLUSION: The over-expression of RhoC protein significantly correlates with advanced TNM stage, lymph node metastasis and cell proliferation ability of ESCC. Therefore, RhoC may be a new auxiliary parameter for early diagnosis and prognostic evaluation of ESCC.  相似文献   
26.
从1973年1月至1995年2月治疗食管癌切除术后胸胃排空障碍11例。10例行11次手术:膈下胸胃十二指肠吻合术1例,胸内胸胃空肠合术2例,幽门区纵行全层切开横行缝合术1例;粘连松解术7例,其中同时行十二指肠松解术1例,幽门成形术2例。术后均解除梗阻。还就此症的诊断和预防作了讨论。  相似文献   
27.
AIM:To investigate endocrine differentiation and its mechanism in endometrial carcinoma.METHODS:Endocrine cells (EC) were identified by immunohistochemical staining of chromogranin A in 50 cases of endometrioid adenocarcinoma and 20 cases of normal endometrium. Double-label techniques were used for simultaneous demonstration of the CgA and cytokeratin.RESULTS:The positive rate of CgA in endometrioid adenocarcinoma was 44.0%, and was significant higher than that in normal endometrium (15.0%, P<0.05). Scanty EC was present in normal endometrium. The number and staining intensity of EC in endometrioid adenocarcinoma were greater than that in normal. Co-expression of CgA and cytokeratin were detected in endometrioid adenocarcinoma.CONCLUSION:The presence of endocrine cells in endometrioid adenocarcinoma showed heterogeneity of tumors. The occurrence of "Multidirectional differentiation cells" within the endometrioid adenocarcinoma may indicate that endocrine cells derive from malignant cells of multidirectional differentiation.  相似文献   
28.
AIM: To study the mechanism of the effect of NSAIDs on apoptosis in mice hepatoma at anti-inflammatory doses. METHODS: Kunming breed mice were inoculated subcutaneously in the flank with mice hepatoma H22 cell line. The effects of ibuprofen, indomethacin, and nimesulide on apoptosis were determined by using electron microscopy, agarose gel electrophoresis, flow cytometry, and Western blot analysis of the expression of c-myc, bcl-xL and bcl-2 proteins. RESULTS: NSAIDs induced apoptosis of mice implanted hepatoma, which includes the morphological changes such as reduction in the volume, and the nuclear chromatin condensation, as well as the "ladder pattern" revealed by agarose gel electrophoresis of DNA. The apoptotic index was increased to 15%±1.0%, 29.7%±1.5%, 46.3%±3.5% from 3.3%±0.6% by detecting Sub-G1 peaks on flow cytometry. Western blot analysis showed that levels of bcl-2 and bcl-xL were significantly reduced by treatment with nimesulide. Ibuprofen and indomethacin decreased bcl-2 expression but increased bcl-xL expression. C-myc wasn't changed in these groups. CONCLUSION: These results suggest that NSAIDs induces apoptosis of mice hepatoma, which may be due to their regulation on the expressions of bcl-2 family genes.  相似文献   
29.
AIM:To investigate the expression of mitogen activated protein kinase kinase 4 (MKK-4) and MMP-9 mRNA in primary hepatic carcinoma (PHC), and to analyze its relationship with invasion and metastasis. METHODS:The expression of MKK-4 and MMP-9 mRNA in 34 cases of hepatic carcinoma tissues and adjacent tissues,and in 12 cases of normal liver tissues were detected with RT-PCR. RESULTS:(1) The expression level of MMP-9 mRNA was higher in metastatic cancer tissues than that in other tissuses (P<0.01). (2) There was significant statistical difference among the expression level of MKK-4 mRNA, but the level in metastatic cancer was low (P<0.01). (3) There was no statistical difference among the expression level of MKK-4 or MMP-9 mRNA among the adjacent tissues and normal tissues (P>0.05). (4) MMP-9 mRNA had a tendency to rise as PHC became invasive and metastatic.The expression level of MKK-4 had a tendency to decline in PHC became invasive and metastatic. (5) The expression level of MMP-9 or MKK-4 mRNA had no correlations with tumor volume,or cell differentiation (P>0.05). (6) There were correlations between expressions of MKK-4 and MMP-9 mRNA in PHC (Pearson Correlation, r=-0.925, P<0.01). CONCLUSION:There are high MMP-9 mRNA expression and low MKK-4 mRNA expression in PHC.The expression level of MKK-4 or MMP-9 mRNA is correlated with tumor metastasis.  相似文献   
30.
AIM: To examine the latent membrane protein 1(LMP1)-DNA sequence in nasopharyngeal carcinoma(NPC) and detect mRNA expression of LMP1,EBNA1,EBNA2,and to explore the relationship between EBV infectious status,expression products and NPC carcinogenesis.METHODS: LMP1 DNA was detected in NPC by PCR.Direct sequence was applied to analyze the difference between NPC-LMP1-DNA and B95-8- LMP1-DNA.mRNA expressions of LMP1,EBNA1,EBNA2 in NPC were detected by nested RT-PCR.RESULTS: LMP1 DNA existed in all 47 NPC tissues.Several single nucleotide variations were found between NPC-LMP1-DNA and B95-8- LMP1-DNA.The notable variation was the lost of XhoⅠrestriction site in NPC.Direct sequence showed 30 bp deletion in NPC.The mRNA expressions of LMP1,EBNA1 and EBNA2 in NPC were 76.6%,80.0% and 74.5% respectively by nested RT-PCR.The expression of EBNA1 in NPC was promoted by Q promoter while the expression of EBNA1 in B95-8 was promoted by C promoter.CONCLUSION: The way of EBV involved in NPC is complex.Latent genes such as LMP1,EBNA1 and EBNA2 as well as early lytic gene BARF1 may all play certain roles in NPC carcinogenesis.  相似文献   
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