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1.
目的:探讨踝肱指数(ABI)与糖尿病周围神经病变及中医证候积分的相关性。方法:选取我院内分泌科收治辩证以气阴两虚 为证型的糖尿病患者66 例,根据踝肱指数实验将患者分为ABI降低组(0.9>ABI>0.5)和ABI 正常组(1.4>ABI>0.9)。记录患者神 经病变症状尼龙丝检查以及中医症候评分,分析ABI与糖尿病周围神经病变及中医证候积分的相关性。结果:ABI降低组的糖尿 病周围神经病变的患病率高于ABI正常组(P<0.05)。ABI 降低组发麻、针刺感症状的发生率高于ABI 正常组,且有统计学差异 (P<0.05)。ABI降低组10 g尼龙丝检查异常者多于ABI正常组,差异显著(P<0.05)。ABI降低组的感觉振动阈值高于ABI正常组 (P<0.05)。ABI数值与中医证候积分呈负向直线相关(P<0.05)。结论:糖尿病患者ABI数值与糖尿病周围神经病变和中医证候积 分具有相关性。  相似文献   
2.
目的:探讨癌基因Src在体外培养骨肉瘤细胞侵袭伪足形成中的作用。方法:构建Src sh RNA慢病毒表达载体,在HEK293T细胞中包装慢病毒,感染HT-1080骨肉瘤细胞,经嘌呤霉素加压筛选,获得稳定沉默Src基因的骨肉瘤细胞系HT-1080-sh Src;实时定量PCR和Western Blot法检测基因沉默效率;采用原位明胶酶谱法检测侵袭伪足形成;采用侵袭小室实验检测下调Src基因表达对HT-1080细胞侵袭力的影响。结果:成功构建稳定沉默Src基因的骨肉瘤细胞系HT-1080-sh Src及对照细胞系HT-1080-shluc,经实时定量PCR和Western Blot检测,与对照细胞系相比,HT-1080-sh Src细胞中Src基因表达下调3倍以上;下调HT-1080细胞中Src基因表达能显著抑制HT-1080细胞侵袭伪足形成及其对细胞外基质的降解能力;下调Src基因表达能显著抑制骨肉瘤细胞侵袭力。结论:癌基因Src参与调节骨肉瘤细胞HT-1080侵袭伪足形成,促进肿瘤侵袭、转移。  相似文献   
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The aim of our study was to investigate the appearance, density and distribution of ghrelin cells and GHS-R1a and GHS-R1b in the human stomach and duodenum during prenatal and early postnatal development. We examined chromogranin-A and ghrelin cells in duodenum, and GHS-R1a and GHS-R1b expression in stomach and duodenum by immunohistochemistry in embryos, fetuses, and infants. Chromogranin-A and ghrelin cells were identified in the duodenum at weeks 10 and 11 of gestation. Ghrelin cells were detected individually or clustered within the base of duodenal crypts and villi during the first trimester, while they were presented separately within the basal and apical parts of crypts and villi during the second and third trimesters. Ghrelin cells were the most numerous during the first (∼11%) and third (∼10%) trimesters of gestation development. GHS-R1a and GHS-R1b were detected at 11 and 16 weeks of gestation, showed the highest level of expression in Brunner's gland and in lower parts of duodenal crypts and villi during the second trimester in antrum, and during the third trimester in corpus and duodenum. Our findings demonstrated for the first time abundant duodenal expression of ghrelin cells and ghrelin receptors during human prenatal development indicating a role of ghrelin in the regulation of growth and differentiation of human gastrointestinal tract.  相似文献   
6.
The main goal of our research was to study comprehensively the differences between the two phenological forms of the socially parasitic and globally threatened Large Blue (Maculinea arion) in the Carpathian Basin using four character sets (mitochondrial sequences, allozymes, male genitalia and wing morphometrics). Comparative analyses of distance matrices, phylogenetic trees and ordination patterns have been applied. The genetic and morphometric patterns revealed by our studies were discordant. While we experienced a significant differentiation between the ‘spring’ and ‘summer type’ of M. arion in both wing and genital traits, the two phenological forms did not show any genetic differentiation on two mitochondrial loci and in allozymes. At the same time, all individuals were infected by Wolbachia. Although certain wing traits may not represent reliable tracers of phylogeny because of the particular adaptive significance, the wing characteristics involved in our research are probably determined genetically. Additionally, the significant differentiation of male genitalia also indicates incipient prezygotic isolation arising from phenological differentiation between the ‘spring and summer arion’. It is possible that all extant differences between the two forms are attributable to (1) different host‐ant use, (2) incipient speciation, (3) cytoplasmatic incompatibility (CI) by Wolbachia or the combination of these factors. In addition, discordant results indicate that the combined use of different approaches and data sets is strictly necessary to clarify systematic and evolutionary relationships.  相似文献   
7.
The aim of this study was to analyze the growth response of HeLa cells over a prolonged period of time to a single exposure of physiological and supraphysiological concentrations of 4-hydroxynonenal (HNE), a peroxidation product of omega-6-polyunsaturated fatty acids. Furthermore, the growth modulating effect of serum factors, particularly albumin, on the growth pattern was examined. The effects of HNE on the growth rate and viability of the cells, as well as on the incorporation of labelled amino acids were monitored daily over a period of four days. Fetal calf serum not only had a growth stimualting effect but also modulated the action of HNE. In neither respect was albumin able to substitute for serum indicating that the influence of serum was not exerted via an albumin–HNE conjugate. HNE had a clear dose-dependent effect and a distinction could be made between a supraphysiological concentration (100 μM), which was primarily cytotoxic and a physiological range (below 10 μM) which showed growth modulatory effects. These effects consisted of a transient inhibition in the initial phase of the cell growth, which under optimal conditions (in presence of serum) was followed by a period of increased proliferation, compared to untreated control cultures, until confluence was attained. It is suggested that HNE is not only a toxic product of lipid peroxidation, but a physiological growth regulating factor as well.  相似文献   
8.
Abstract A cluster of five to seven AKH-like immunoreactive cells lie in each lobe of the paired corpora cardiaca of the true armyworm, Pseudaletia unipuncta. These cells form a mesh work of immunoreactive processes within the corpora cardiaca, and immunoreactive tracts projecting posteriorly over the aorta.
Reversed-phase high performance liquid chromatography of extracts of the corpora cardiaca of P.unipuncta revealed a single large U.V. absorbent peak with a retention time identical to synthetic Manduca- AKH. Amino acid analysis of the contents of this peak yielded a composition identical to that of synthetic Manduca-AKH which was analysed in a parallel manner. Furthermore the material within the peak possessed adipokinetic activity when bioassayed in day 2 adult male P. unipuncta. The corpora cardiaca of similar individuals were found to contain approximately 17.6ng (17.6pmol) of Manduca-AKH equivalents per pair.
Injection of Manduca-AKH into 2-day-old adult male P.unipuncta resulted in a dose-dependent elevation in haemolymph lipid levels with a maximum level of 80–90μmg/μl obtained with 5–10 ng of Manduca-AKH. Continuous flight also elevated haemolymph lipid levels in day 4 adult males with a significant elevation evident in the first samples taken after 15 min of flight and lipid levels plateauing at approximately 100 μg/μl by about 60 min of flight.  相似文献   
9.
We have reported recently that prostaglandin E2 (PGE2) stimulated phosphoinositide metabolism in bovine adrenal chromaffin cells and that PGE2 and ouabain, an inhibitor of Na+, K(+)-ATPase, synergistically induced a gradual secretion of catecholamines from the cells. Here we examined the involvement of a GTP-binding protein(s) in PGE receptor-induced responses by using NaF. In the presence of Ca2+ in the medium, NaF stimulated the formation of all three inositol phosphates, i.e., inositol monophosphate, bisphosphate, and trisphosphate, linearly over 30 min in a dose-dependent manner (15-30 mM). This effect on phosphoinositide metabolism was accompanied by an increase in cytosolic free Ca2+. NaF also induced catecholamine release from chromaffin cells, and the dependency of stimulation of the release on NaF concentration was well correlated with those of NaF-enhanced inositol phosphate formation and increase in cytosolic free Ca2+. Although the effect of NaF on PGE2-induced catecholamine release in the presence of ouabain was additive at concentrations below 20 mM, there was no additive effect at 25 mM NaF. Furthermore, the time course of catecholamine release stimulated by 20 mM NaF in the presence of ouabain was quite similar to that by 1 microM PGE2, and both stimulations were markedly inhibited by amiloride, with half-maximal inhibition at 10 microM. Pretreatment of the cells with pertussis toxin did not prevent, but rather enhanced, PGE2-induced catecholamine release over the range of concentrations examined. These results demonstrate that NaF mimics the effect of PGE2 on catecholamine release from chromaffin cells and suggest that PGE2-evoked catecholamine release may be mediated by the stimulation of phosphoinositide metabolism through a putative GTP-binding protein insensitive to pertussis toxin.  相似文献   
10.
Abstract: The turnover of a CNS-specific cell adhesion glycoprotein, ependymin, has earlier been found to increase during periods of neuronal plasticity. Here, ependymin mRNA expression was analyzed by semiquantitative in situ hybridization in goldfish. Learning of an active avoidance response resulted in a significant increase in ependymin mRNA expression 20 min to 4 h after acquisition of the task. In contrast, yoked control animals that were exposed to the same numbers of conditioned and unconditioned stimuli in a random, unpaired manner exhibited a strong down-regulation of ependymin mRNA. Hybridization signals were also increased by injection of anti-ependymin antiserum into brain ventricles. Ependymin mRNA was exclusively localized to reticular-shaped fibroblasts of the inner endomeningeal cell layer. Immunoelectron microscopic investigation, however, revealed ependymin also in distinct neuronal and glial cell populations in which no ependymin mRNA had been detected. Uptake of meningeal protein factors into glial and neuronal cells may therefore be of functional importance for plastic adaptations of the CNS.  相似文献   
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