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排序方式: 共有7891条查询结果,搜索用时 15 毫秒
41.
Wen Jie Tian Seung Hwan Jeon Guan Qun Zhu Eun Bi Kwon Ga Eun Kim Woong Jin Bae Hyuk Jin Cho U-Syn Ha Sung-Hoo Hong Ji Youl Lee Kang Sup Kim Sae Woong Kim 《Translational andrology and urology》2021,10(1):345
BackgroundThe purpose of this study is to explore the effects of high-BDNF microenvironment produced by engineered immortalized mesenchymal stem cells (imMSCs) on the neurogenic bladder (NB) and investigate underlying mechanism.MethodsMale Sprague-Dawley rat (12-week-old, weighing about 370–400 g) were purchased from a Korean company (Orient Bio Co. Seongnam, Korea) and divided into the following groups (n=32): sham control group (n=8), NB group (n=8), NB + ImMSCs group (n=8), NB + ImMSCs (BDNF) group (n=8). The major pelvic ganglion (MPG) was observed under anesthesia. Three NB groups of rats were then subjected to bilateral MPG injury. The sham control group of rats was treated with sham surgery. Cystometry were performed before the rats were sacrificed, and then MPG and bladder were collected for histochemical and Western blot analysis.ResultsMSCs treatment improves lower urinary tract function, and the NB + ImMSCs (BDNF) group is better than the NB + ImMSCs group (P<0.01). MSCs treatment accelerates recovery of injured nerve tissue, and the NB + ImMSCs (BDNF) group is better than the NB + ImMSCs group (P<0.01). In high BDNF environment, apoptosis was reduced more significantly and muscle tissue recovered more rapidly (P<0.01). High-BDNF microenvironment activates more BDNF/TrkB/CREB signaling pathways (P<0.01).ConclusionsIn a rat NB model caused by nerve injury, imMSCs have certain effects on nerve tissue repair. At the same time, it was proved that increasing the expression of BDNF which had specific effect on nerve injury repair could more effectively repair injured MPG in local microenvironment. The mechanism may be related to the activation of the BDNF/TrkB/CREB signaling pathway and the reduction of apoptosis by highly expressed BDNF. 相似文献
42.
Behavioral characteristics of a mouse model of cancer pain 总被引:5,自引:0,他引:5
Pain is a major symptom in cancer patients, and most cancer patients with advanced or terminal cancers suffer from chronic pain related to treatment failure and/or tumor progression. In the present study, we examined the development of cancer pain in mice. Murine hepatocarcinoma cells, HCa-1, were inoculated unilaterally into the thigh or the dorsum of the foot of male C3H/HeJ mice. Four weeks after inoculation, behavioral signs were observed for mechanical allodynia, cold allodynia, and hyperalgesia using a von Frey filament, acetone, and radiant heat, respectively. Bone invasion by the tumor commenced from 7 days after inoculation of tumor cells and was evident from 14 days after inoculation. Cold allodynia but neither mechanical allodynia nor hyperalgesia was observed in mice that received an inoculation into the thigh. On the contrary, mechanical allodynia and cold allodynia, but not hyperalgesia, were developed in mice with an inoculation into the foot. Sometimes, mirror-image pain was developed in these animals. These results suggest that carcinoma cells injected into the foot of mice may develop severe chronic pain related to cancer. This animal model of pain would be useful to elucidate the mechanisms of cancer pain in humans. 相似文献
43.
44.
Hwan Bae Lee Jong Hwan Kwak Ok Pyo Zee Seung Jo Yoo 《Archives of pharmacal research》1994,17(4):273-277
Six flavonoids were isolated from the aerial parts ofCirsium rhinoceros. The flavonoids were identified as apigenin, luteolin, pectolinarigenin-7-O-β-D-glucopyranoside, linarin, pectolinarin and hispidulin-7-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside on the basis of chemical and spectral evidence. 相似文献
45.
46.
D S Kim M S Lee D H Kim J M Bae M H Shin C M Lee H W Koo W Kang Y O Ahn 《Journal of epidemiology / Japan Epidemiological Association》1999,9(3):146-154
Since the completeness of case ascertainment is directly related to the validity of a study, the evaluation of completeness is an essential feature of a cohort study. To estimate the completeness of cancer case ascertainment during a three year period (Jan. 1, 1993, to Dec. 31, 1995) in which the Seoul Male Cohort was followed up, we applied capture-recapture method. Data were obtained from the cancer registries, medical records and death certificates, with cases identified from each source numbering 103, 105, and 38, respectively. After eliminating duplicate cases, the total number was 141, and by using a log-linear model, the number of cases not detected by any of the three data sources was estimated to be 16. For all cancers, the estimated completeness of follow-up was 89.9%. 相似文献
47.
B S Min H J Jung J S Lee Y H Kim S H Bok C M Ma N Nakamura M Hattori K Bae 《Planta medica》1999,65(4):374-375
The methanol extracts of the leaves of Crataegus pinnatifida showed potent inhibitory activities against HIV-1 protease at a concentration of 100 micrograms/ml. The subsequent fractionation and isolation of the extract gave two active compounds. Their structures were identified as uvaol (1) and ursolic acid (2) by spectral data. These active compounds inhibit HIV-1 protease with IC50 values of 5.5 and 8.0 microM, respectively. 相似文献
48.
Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans. 相似文献
49.
When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin. 相似文献
50.
Hak Cheol Kwon Sang Un Choi Jung Ock Lee Ki Hwan Bae Ok Pyo Zee Kang Ro Lee 《Archives of pharmacal research》1999,22(4):417-422
Two new furanolignans (3, 5), together with three known lignans (1, 2, 4), were isolated from the stem of Lindera obtusiloba (Lauraceae). The structures of the compounds were determined as actifolin (1), pluviatilol (2), 5,6-dihydroxymatairesinol (3), (+)-syringaresinol (4), and (+)-9'-O-trans-feruloyl-5,5'-dimethoxylariciresinol (5) on the basis of physicochemical and spectroscopic evidences. Compounds 1, 2, 3, and 5 showed cytotoxicity against a small panel of human tumor cell lines with ED50 values of 3.40 to approximately 19.27 microg/ml. 相似文献