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191.
192.
The effects of 5-hydroxytryptamine (5-HT) on several types of neuronal injury in mouse cortical cell cultures were tested. Co-treatment with 5-HT prevented free radical-mediated neuronal necrosis induced by FeCl2 or buthionine sulfoximine (BSO) in a dose-dependent manner. Subtype antagonists did not reverse the protective effect and 5-HT showed direct free radical scavenging activity evidenced by its ability to reduce the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) in a cell-free system. Excitotoxic necrosis induced by NMDA or apoptosis induced by staurosporine was not sensitive to 5-HT treatment. These features raise the possibility that the endogenous neurotransmitter 5-HT may work as an innate antioxidant defense mechanism in the CNS. 相似文献
193.
194.
据文献记载和作者的调查,我国产麻黄属(Ephedra)植物共有13种3变种1变型。本文报道我国北方生产的7种麻黄生药形态组织学比较研究结果。7种麻黄是:草麻黄Ephedra sinica Stapf、木贼麻黄E.equisetina Bunge、中麻黄E.intermedia Schrenk ex Mey.、膜果麻黄E.przewalskii Stapf,单子麻黄E.monosperma Gmel.ex Mey.、雌雄麻黄E.fedtschenkoae Pauls和细子麻黄E.reaeliana Florin。文中附有生药性状与组织构造特征比较表及生药组织图 相似文献
195.
196.
High glucose increases inducible NO production in cultured rat mesangial cells. Possible role in fibronectin production. 总被引:7,自引:0,他引:7
Hyunjin Noh Hunjoo Ha Mi Ra Yu Shin Wook Kang Kyu Hun Choi Dae Suk Han Ho Yung Lee 《Nephron》2002,90(1):78-85
BACKGROUND/AIM: Increased nitric oxide (NO) generation and action have been suggested to be associated with glomerular hyperfiltration and increased vascular permeability early in diabetes. However, previous studies have primarily focused on the constitutive nitric oxide synthase (cNOS) pathway present in endothelial cells, and the role of the inducible NOS (iNOS) pathway in diabetic nephropathy has remained unclear. This study examined whether high glucose modulates NO synthesis by the iNOS pathway in rat mesangial cells. In addition, the effect of inhibition of the iNOS pathway on fibronectin production was determined to examine the role of the iNOS pathway in high glucose-induced extracellular expansion by mesangial cells. METHODS: NO synthesis by the iNOS pathway was evaluated by nitrite and iNOS mRNA and protein productions. The effects of protein kinase C (PKC) inhibitor and aldose reductase inhibitor on the iNOS mRNA expression and aminoguanidine, a relatively specific inhibitor of the iNOS on fibronectin protein production were examined. RESULTS: High 30 mM glucose concentration led to significant increases in nitrite production of rat mesangial cells upon stimulation with lipopolysaccharide (LPS) plus interferon-gamma (IFN-gamma) compared with control 5.6 mM glucose concentration. Mesangial iNOS mRNA expression and protein production also increased significantly in response to high glucose. The addition of calphostin C, a PKC inhibitor, and 6-bromo-1,3-dioxo-1H-benz[d,e]isoquinoline-2(3H)-acetic acid, an aldose reductase inhibitor, significantly suppressed the enhancement of iNOS mRNA expression in high glucose concentration. High glucose also significantly increased fibronectin protein production of mesangial cells upon stimulation with LPS plus IFN-gamma compared to control glucose. Aminoguanidine reversed this high glucose-induced fibronectin production at dose inhibiting iNOS mRNA expression. CONCLUSIONS: These results indicate that high glucose enhances cytokine-induced NO production by rat mesangial cells, and that the activation of PKC and aldose reductase pathway may play a role in this enhancement. In addition, high glucose-induced NO production by the iNOS pathway may promote extracellular matrix accumulation by mesangial cells under certain condition. 相似文献
197.
Daniel TP Fong Mak-Ham Lam Miko LM Lao Chad WN Chan Patrick SH Yung Kwai-Yau Fung Pauline PY Lui Kai-Ming Chan 《Journal of orthopaedic surgery and research》2008,3(1):7
Background
Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running. 相似文献198.
199.
Chen Li Sungsoo Kim Ji Fu Lai Sung Jin Oh Woo Jin Hyung Won Hyuk Choi Seung Ho Choi Sung Hoon Noh 《Journal of gastrointestinal surgery》2008,12(3):550-554
The feasibility and diagnostic reliability of sentinel node (SN) biopsy for gastric cancer are still controversial. We studied
the clinicopathological features and localization of solitary lymph node metastasis (SLM) in gastric cancer to provide useful
information for use of the SN concept in gastric cancer. From 2000 to 2004, 3,267 patients with gastric cancer underwent D2
radical gastrectomy. The clinicopathological features of 195 patients with histologically proven SLM and the distribution
of metastasized nodes were assessed. The incidence of SLM was 6.0% in all cases. Compared with the node-negative patients,
significant differences were observed in age, tumor size, depth of invasion, and surgical type. The cumulative 5-year survival
rate of patients with SLM was 80.5%, which was significantly lower than 90.2% for node-negative patients (P < 0.001). Of patients with SLM, 82.6% had it in the perigastric node area (N1), and the other 17.4% patients had skip metastasis
in the N2-N3 nodes. Perigastric nodes were the most common first sites of drainage from the tumor, making them the main targets
of the operative SN mapping procedure. Due to the higher than expected incidence of skip metastasis in gastric cancer, D2
lymphadenectomy should be performed until the reliability of SN navigation surgery is validated in multicenter prospective
clinical trials. 相似文献
200.
H. Nakazawa N. Ishikawa J. Noh T. Sugimoto M. Yoshimoto T. Yashiro O. Ozaki K. Ito 《European journal of clinical pharmacology》1991,40(3):215-219
Summary Rhythm conversion in patients with post-thyrotoxic atrial fibrillation (AF) has been performed with disopyramide in order to evaluate the conversion rate and to test its effect on the maintenance of sinus rhythm after cardioversion.The duration of AF ranged from 9 to 122 months (mean 31.8 months). Of 81 patients, 12 (15%) with relatively short duration AF were converted to sinus rhythm with disopyramide. The remaining 69 patients required DC cardioversion, which restored sinus rhythm in 58 patients. The 58 DC-converted patients were divided into two groups: a disopyramide group (D group) and a non-disopyramide group (non-D group). The D group received disopyramide 300 mg per day for 3 months after DC cardioversion and the non-D group did not receive anti-arrhythmic drugs. During the early observation period, only one patient relapsed in the D group into AF, but 5 successive patients in the non-D group reverted to AF, forcing discontinuation of the non-D protocol. A second DC cardioversion performed on 3 of those 5 patients was followed by maintenance therapy with disopyramide 300 mg per day, and they remained in sinus rhythm. With the inclusion of those three subjects, sinus rhythm was still present in 44 of the total of 58 patients converted by DC (76%) at the time of follow-up (64 months).Thus, disopyramide was effective in rhythm conversion and it was essential for the maintenance of sinus rhythm after cardioversion in patients with post-thyrotoxic AF. 相似文献