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排序方式: 共有6920条查询结果,搜索用时 15 毫秒
1.
目的:探讨miR-26b参与原发性肝细胞肝癌(HCC)侵袭的机制。方法:在细胞培养液中培养人肝细胞系HL-7702和HCC细胞各系Hepb-3、HuH-7、MHCC97-L、MHCC97-H。实时荧光定量PCR法(qRT-PCR)检测miR-26b的表达水平;用miR-26b mimics、miR-26b inhibitors和Notch1-siRNA分别转染HCC细胞;MTT实验检测转染后HCC细胞的活力;采用Western blot检测Notch1受体蛋白表达水平的变化;Transwell小室测定不同处理后的HCC细胞的侵袭能力。结果:人正常肝细胞系HL-7702和HCC细胞系Hepb-3、HuH-7、MHCC97-L、MHCC97-H中的miR-26b相对表达含量随其侵袭和迁移能力的升高而依次下降;抑制miR-26b的表达,Notch1受体蛋白表达明显增高,而此时HCC细胞的侵袭性显著增强;相反,上调miR-26b的表达,Notch1受体蛋白表达明显降低,而HCC细胞侵袭性显著下降;miR-26b可能通过调控Notch1信号通路调节HCC细胞侵袭性。结论:miR-26b通过负调控Notch1信号通路抑制HCC细胞侵袭能力,为HCC侵袭的机制奠定了理论基础,miR-26b可能成为HCC治疗的新靶点。 相似文献
2.
Rena Fushiki Kotoe Mayahara Mai Ogawa Yasuyo Takahashi Yoko Karasawa Niina Tsurumachi 《Connective tissue research》2015,56(4):336-341
Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2. 相似文献
3.
Yamaoka Mai Yoshida Mahoko Nakashima Ayumu Doi Shigehiro Naito Takayuki Masaki Takao 《Clinical and experimental nephrology》2022,26(11):1111-1118
Clinical and Experimental Nephrology - The association between N-terminal pro-brain natriuretic peptide (NT-proBNP) and stroke in Japanese hemodialysis (HD) outpatients is unclear. Therefore, in... 相似文献
4.
Satoshi Iyama Yasuo Takahashi Naoaki Shintani Koshi Fujikawa Syunichi Ohkubo Yasushi Sato Tsutomu Sato Yasuhiro Sato Keisuke Ohnuma Yoshiro Niitsu 《Nihon Shokakibyo Gakkai zasshi》2006,103(10):1163-1168
We report a case of biliary cystadenocarcinoma which recurred 41 months postoperatively. A 60-year-old woman was admitted for further examination of multiple metastatic tumors and a large amount of ascites. Systemic administration of 5FU and CDDP caused her CEA level to decrease gradually and abdominal computed tomography revealed considerable reduction of the metastatic tumors and ascites. Since her general condition had improved, chemotherapy was continued in the outpatient clinic. 相似文献
5.
Dinesh Rakheja Payal Kapur Mai P. Hoang Lonnie C. Roy Michael J. Bennett 《Medical hypotheses》2005,65(6):681
Mammalian fatty acid synthase (FASE) overexpression has been shown in a number of human malignancies including colonic adenocarcinoma. Since FASE synthesizes only saturated fatty acids, we hypothesized that cancer cells have a greater proportion of long-chain saturated fatty acids. We studied and found an unequivocal increase in saturated C18 fatty acid (stearic acid) in colonic adenocarcinoma compared to adjacent normal colonic mucosa. The increase is even more striking when measured as a ratio of stearic acid to the unsaturated C18 fatty acids (oleic acid and linoleic acid). This change in fatty acid composition of the cancer cells should significantly alter their physical and biological properties. The increase in relative proportion of saturated fatty acids should make the cancer cells more susceptible to cryodamage and measurement of fatty acid composition of cancer cells may help individualize the temperature for cryotherapy. Also, the lipid alterations may affect the structure and functions of lipid rafts, which may enable the cancer cells to affect signaling mechanisms such as those involved in cell growth and apoptosis. Dietary or therapeutic interventions targeting lipid rafts may thus be an option for cancer treatment. 相似文献
6.
M Shibata T Ohkubo H Takahashi T Kudo R Inoki 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1986,88(2):101-107
Opiates and opioid peptides were administered in the order of 10(-9)-10(-6) mol peripherally, and their action on pain sensitivity was investigated by the modified formalin test which has two characteristic pain responses (the first and the second phase) in the mouse hindpaw. Opioid peptides (20-500 pmol) had dose-dependent analgesia against both first and second phases, and their action ranked dynorphin greater than [D-Ala2, Met5]-enkephalinamide greater than [Met5]-enkephalin. EKC and morphine (0.4-2.5 nmol) inhibited pain response of the first phase, but produced hyperalgesia in the second phase dose-dependently. Lidocaine hydrochloride had peripheral analgesic action, but was about 500-10000 times weaker than these substances. So, these peripheral analgesic actions have a different mechanism from that of local anesthetic action. N-methyl levallorphan which is thought to be a peripherally selective narcotic antagonist reversed these peripheral analgesic actions at the first and second phases and also prevented the hyperalgesic effects of EKC and morphine at the second phase. Naloxone reversed analgesia at only the first phase. These results suggest that an analgesic mechanism by opioids may exist at the peripheral site as well. Furthermore, it is estimated that a receptor exists which is antagonized by N-methyl levallorphan but not by naloxone and that there is a system of hyperalgesia by EKC and morphine in pain modulation. 相似文献
7.
A 35-year-old man was referred to Nihon University Hospital because of repetitive ventricular tachycardia (VT) at 180-200 beats/min. QRS morphology of the VT was right bundle branch block with a northwest axis. Transthoracic echocardiography showed hypertrophic cardiomyopathy. Coronary angiography was normal and left ventriculography showed neither obstruction in the left ventricle (LV) nor any pressure gradients within the LV or between the LV and aorta. Hemodynamic deterioration occurred during VT. Intracardiac mapping showed that the VT originated from the posteroseptal portion of the LV near the apex and Purkinje potentials that preceded the onset of the QRS complex by 58-70 ms were documented. Radiofrequency ablation at these sites terminated the VT, which has not recurred for 25 months. 相似文献
8.
415例糖尿病住院病人年龄分布分析 总被引:1,自引:0,他引:1
目的:为防治糖尿病提供统计数据。方法:采用圆形分布法。最大与最小年龄差值72岁,相当于360°,每1岁相当于6°。结果:糖尿病住院病人入院高峰年龄集中时点为51岁,高峰期年龄为39岁~63岁。 相似文献
9.
Xiao-Mei Mai Per-Olof Gäddlin Lennart Nilsson Ingemar Leijon 《Pediatric allergy and immunology》2005,16(5):380-385
Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness. 相似文献
10.
Fifty-five hematopoietic cell lines, including 19 T-, 16 B-, 5 pre-B-, 5 non-T non-B-, 1 erythroid, and 9 myeloid-monocytoid cells, were screened for production of human hematopoietic survival and stem cell growth factor (SCGF) by enzyme immunoassay using anti-SCGF monoclonal antibody. The KPB-M15 myeloid cell line constitutionally secreted a considerable quantity of SCGF, while other T- or myeloid-monocytoid cell lines did not secrete SCGF. Other biomaterials investigated were fetal calf, horse, and human serum; granulocyte-macrophage colony-stimulating factor and erythropoietin preparations; human placental conditioned medium; lectin (phytohemagglutinin, concanavalin A, and pokeweed mitogen); and mixed leukocyte reaction-stimulated leukocyte-conditioned medium. SCGF was detected only in human placental conditioned medium. SCGF produced by the KPB-M15 cells was a protein with a molecular weight of 20,000. The molecule, highly purified by immunoadsorbent affinity chromatography, retained SCGF activity in vitro, e.g., erythroid burst-promoting activity and granulocyte-macrophage-colony potentiation. With the availability of purified SCGF, it is now possible to study in detail the mechanisms regulating hematopoietic stem cells. 相似文献