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31.
The aim of this study was to investigate the effects of Ginkgo biloba extract (EGb 761) on male copulatory behavior in rats. EGb 761 (1 mg/ml) induced significant production of testosterone (T) in rat Leydig cells in vitro. Its effects on sexual behavior were then tested in Long-Evans male rats after 7, 14, 21, or 28 days of oral gavage of vehicle (distilled water) or EGb 761 at doses of 10, 50, or 100 mg/kg. Administration of 50 mg/kg of EGb 761 for 28 days and of 100 mg/kg for 14 or 21 days significantly increased intromission frequency compared to controls on the same day. An increase in ejaculation frequency was seen after treatment with 50 mg/kg of EGb 761 for 14, 21, or 28 days when compared to either the control group on the same day or the same group on day 0. A reduction in ejaculation latency was only seen after administration of 50 mg/kg of EGb 761 for 14 days compared to the vehicle-treated group. After treatment for 28 days, no significant difference was seen in mount latency, intromission latency, serum T levels, reproductive organ weight, sperm number, or levels of the metabolite of dopamine, 3,4-dihydroxyphenylacetic acid in the brain with any dose of EGb 761, but significantly reduced serum prolactin levels and increased dopamine levels in the medial preoptic area and arcuate nucleus were seen at the dose of 50 mg/kg. These findings show that EGb 761 (especially at the dose of 50 mg/kg) enhances the copulatory behavior of male rats and suggest that the dopaminergic system, which regulates prolactin secretion, may be involved in the facilitatory effect of EGb 761.  相似文献   
32.
Dysregulation of autophagy is associated with the neurodegenerative processes in Alzheimer's disease (AD), yet it remains controversial whether autophagy is a cause or consequence of AD. We have previously expressed the full‐length human APP in Drosophila and established a fly AD model that exhibits multiple AD‐like symptoms. Here we report that depletion of CHIP effectively palliated APP‐induced pathological symptoms, including morphological, behavioral, and cognitive defects. Mechanistically, CHIP is required for APP‐induced autophagy dysfunction, which promotes Aβ production via increased expression of BACE and Psn. Our findings suggest that aberrant autophagy is not only a consequence of abnormal APP activity, but also contributes to dysregulated APP metabolism and subsequent AD pathogenesis.  相似文献   
33.
Non-syndromic low-frequency sensorineural hearing loss(LFSNHL) is an unusual type of hearing loss in which frequencies≤2000 Hz predominantly are affected.To date,different mutations in two genes,DIAPH1 and WFS1,have been found to be associated with LFSNHL. Here,we report a five-generation Chinese family with postlingual and progressive LFSNHL.We mapped the disease locus to a 2.5 Mb region on chromosome 4p16 between markers SNP_A-2167174 and D4S431,overlapping with the DFNA6/14/38 locus.Sequencing of cand...  相似文献   
34.
Macrophage migration inhibitory factor (MIF) is an important cytokine and plays a crucial role as a pivotal regulator of innate immunity. In this study, a MIF cDNA was identified and characterized from the pearl oyster Pinctada fucata (designated as PoMIF). The full-length of PoMIF was 1544 bp and consisted of a 5'-untranslated region (UTR) of 45 bp, a 3'-UTR of 1139 bp with a polyadenylation signal (AATAAA) at 12 nucleotides upstream of the poly (A) tail. The open reading frame (ORF) of PoMIF was 360 bp which encoded a polypeptide of 120 amino acids with an estimated molecular mass of 13.3 kDa and a predicted pI of 6.1. SMART analysis showed that PoMIF contained the catalytic-sites P2 and K33 for tautomerase activity, a motif C??GSV?? for oxidoreductase activity and a MIF family signature D??PCGSVEVYSIGALG??. Homology analysis revealed that the PoMIF shared 40.3-65.5% similarity and 26.9-45.0% identity to other known MIF sequences. PoMIF mRNA was constitutively expressed in seven selected tissues of healthy pearl oysters, with the highest expression level in digestive gland. Eight hours after P. fucata was injected with Vibrio alginolyticus, the expression of PoMIF mRNA was significantly up-regulated in digestive gland, gills, hemocytes and intestine. The cDNA fragment encoding mature protein of PoMIF was subcloned to expression vector pRSET and transformed into Escherichia coli BL21 (DE3). The recombinant PoMIF (rPoMIF) was expressed and purified under optimized conditions. Function analysis showed that rPoMIF had oxidoreductase activity and could utilize dithiothreitol (DTT) as reductant to reduce insulin.  相似文献   
35.
Pu J  Peng G  Li L  Na H  Liu Y  Liu P 《Journal of lipid research》2011,52(7):1319-1327
Chronic exposure to saturated fatty acids can cause insulin resistance. However, the acute effects of fatty acids are not clear and need to be elucidated because plasma fatty acid concentrations fluctuate postprandially. Here, we present the acute effects of palmitate (PA) on skeletal muscle cells and their underlying molecular mechanisms. Immuno-fluorescence results showed that PA rapidly induced GLUT4 translocation and stimulated glucose uptake in rat skeletal muscle cell line L6. Phosphorylation of AMP-activated protein kinase (AMPK), Akt, and extracellular signal-related kinase1/2 (ERK1/2) was enhanced by PA in a time-dependent manner. Cell surface-bound PA was sufficient to stimulate Akt phosphorylation. The inhibitors of PI3 kinase (PI3K), AMPK, Akt, and ERK1/2 could decrease PA-induced glucose uptake, and PI3K inhibitor decreased AMPK, Akt, and ERK1/2 phosphorylation. Weakening AMPK activity reduced phosphorylation of Akt but not ERK1/2, and Akt inhibitor could not affect ERK1/2 activation either. Meanwhile, ERK1/2 inhibitors had no effect on Akt phosphorylation. Taken together, our data suggest that PA-mediated glucose uptake in skeletal muscle cells may be stimulated by the binding of PA to cell surface and followed by PI3K/AMPK/Akt and PI3K/ERK1/2 pathways independently.  相似文献   
36.
目的探讨环氧合酶2(COX-2)在宫颈癌组织中的表达与月经周期的关系及其临床意义。方法选取47例未绝经宫颈癌手术病人,病史结合子宫内膜HE染色观察判断患者所处月经周期时段,采用免疫组织化学SP法检测宫颈癌组织中COX-2及增殖细胞核抗原(PCNA)的表达,计算机图像分析COX-2免疫染色密度值及PCNA标记指数(LI)。结果宫颈癌组织中COX-2表达阳性者增生期表达强于分泌期(P<0.05),但阳性率无显著性差异(P>0.05),COX-2阳性癌组织中PCNALI高于阴性者,差异有显著性(P<0.01)。有淋巴结转移者COX-2的表达高于无转移者(P<0.05),宫颈癌组织中COX-2的表达与FIGO临床分期、组织分化程度无显著相关性(P>0.05)。结论未绝经宫颈癌患者肿瘤组织中COX-2的表达在增生期较分泌期明显增加,并参与调节肿瘤的生长、转移。  相似文献   
37.
DArT and SSR markers were used to saturate and improve a previous genetic map of RILs derived from the cross Chuan35050 × Shannong483. The new map comprised 719 loci, 561 of which were located on specific chromosomes, giving a total map length of 4008.4 cM; the rest 158 loci were mapped to the most likely intervals. The average chromosome length was 190.9 cM and the marker density was 7.15 cM per marker interval. Among the 719 loci, the majority of marker loci were DArTs (361); the rest included 170 SSRs, 100 EST-SSRs, and 88 other molecular and biochemical loci. QTL mapping for fatty acid content in wheat grain was conducted in this study. Forty QTLs were detected in different environments, with single QTL explaining 3.6-58.1% of the phenotypic variations. These QTLs were distributed on 16 chromosomes. Twenty-two QTLs showed positive additive effects, with Chuan35050 increasing the QTL effects, whereas 18 QTLs were negative with increasing effects from Shannong483. Six sets of co-located QTLs for different traits occurred on chromosomes 1B, 1D, 2D, 5D, and 6B.  相似文献   
38.
39.
PcrA DNA helicase uses the free energy of hydrolysis and binding of ATP to unwind double-stranded DNA (ds-DNA). There are two states of PcrA, termed the substrate and product complexes and, through the conformational changes between these two states, PcrA moves along ds-DNA and separates the two strands. In this study, two different methods, namely chain minimisation (CM, less reliable method) and auto targeted molecular dynamic (TMD) simulation (more reliable), were performed to generate two different initial reaction pathways between these two states, and then fixed root mean square distance (RMSD) TMD simulation was performed to optimise these two initial pathways. In general, the two optimised pathways share very similar major conformational changes, but are different in the minor motions. The potential energy profiles of the two improved pathways are generally similar, but the one generated by the improved TMD path is slightly lower. Considering the poor reliability of the initial path generated by CM and insignificant improvements of the auto-TMD path, our study suggests that fixed RMSD TMD simulation can generate reliable reaction pathways, but the different initial paths still have some influence on the detailed conformational analysis.  相似文献   
40.
A new species of Elsholtzia, E. litangensis C. X. Pu & W. Y. Chen, is described and illustrated from Sichuan, Tibet and Qinghai. The diagnostic features of the new species are compared with E. fruticosa (D. Don) Rehd. Elsholtzia litangensis is characterized by a secund spike and a scaly buds in the leaf axils.  相似文献   
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