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101.
目的:探讨阿司匹林联合神经节苷脂治疗脑梗塞的临床疗效及可能机制。方法:选择我院2015年5月到2018年3月接诊的90例脑梗塞患者,依照抽签法将其分为实验组和对照组,每组45例。两组患者均给予常规支持治疗,对照组在此基础上给予阿司匹林治疗,实验组在对照组的基础上给予单唾液酸四己糖神经节苷脂(Monosialyl tetrahexose ganglioside, GM1)治疗。据患者美国国立卫生研究院卒中量表(National Institutes of Health Stroke Scale, NIHSS)和Barthel指数评分的改善情况,比较两组的疗效,以及治疗前后血清过氧化脂质(lipid peroxide, LPO)、超氧化物歧化酶(superoxide dismutase, SOD)、丙二醛(malondialdehyde, MDA)、一氧化氮(nitric oxide, NO)水平的变化。结果:治疗后,实验组有效率为96.86%,显著高于对照组(78.13%,P<0.05)。两组治疗后血清SOD水平及Barthel指数均较治疗前显著上升,而血清LPO、MDA、NO水平及NIHSS评分均较治疗前显著下降,实验组血清SOD水平及Barthel指数显著高于对照组,血清LPO、MDA、NO水平及NIHSS评分均明显低于对照组(P<0.05)。结论:阿司匹林联合GM1能提高脑梗塞的疗效,可能与有效提高血清SOD水平及降低LPO、MDA、NO水平有关。  相似文献   
102.
Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from China, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.  相似文献   
103.
Type 1 diabetes mellitus is believed to be due to the autoimmune destruction of β-cells by T lymphocytes, but a single course of rituximab, a monoclonal anti-CD20 B lymphocyte Ab, can attenuate C-peptide loss over the first year of disease. The effects of B cell depletion on disease-associated T cell responses have not been studied. We compare changes in lymphocyte subsets, T cell proliferative responses to disease-associated target Ags, and C-peptide levels of participants who did (responders) or did not (nonresponders) show signs of β-cell preservation 1 y after rituximab therapy in a placebo-controlled TrialNet trial. Rituximab decreased B lymphocyte levels after four weekly doses of mAb. T cell proliferative responses to diabetes-associated Ags were present at baseline in 75% of anti-CD20- and 82% of placebo-treated subjects and were not different over time. However, in rituximab-treated subjects with significant C-peptide preservation at 6 mo (58%), the proliferative responses to diabetes-associated total (p = 0.032), islet-specific (p = 0.048), and neuronal autoantigens (p = 0.005) increased over the 12-mo observation period. This relationship was not seen in placebo-treated patients. We conclude that in patients with type 1 diabetes mellitus, anti-B cell mAb causes increased proliferative responses to diabetes Ags and attenuated β-cell loss. The way in which these responses affect the disease course remains unknown.  相似文献   
104.
麻风树(Jatropha curcas)是世界上最有潜力的能源植物之一。本研究针对来自全国6省区的219份麻风树种质资源,应用SSR分子标记对其进行了初步的遗传多样性分析。根据公共数据库中的所有序列设计出了20对SSR及4对eSSR引物,这些引物均能很好地扩增麻风树DNA片段。在上述24个SSR标记中,有8个(33.33%)探测到麻风树群体的DNA多态性。这24个SSR标记共扩增出36个位点,平均每个标记扩增1.5个位点,其中12个(33.33%)位点显现出多态性。这表明中国麻风树是一个具有中等SSR多态性水平的物种,其多态百分率为33.3%。  相似文献   
105.
106.
Neural stem cells (NSCs) constitute the cellular basis for embryonic brain development and neurogenesis.The processis regulated by NSC niche including neighbor cells such as vascular and glial cells.Since both vascular and glial cellssecrete vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF),we assessed the effect ofVEGF and bFGF on NSC proliferation using nearly homogeneous NSCs that were differentiated from mouse embryonicstem cells.VEGF alone did not have any significant effect.When bFGF was added,however,VEGF stimulated NSCproliferation in a dose-dependent manner,and this stimulation was inhibited by ZM323881,a VEGF receptor (Flk-1)-specific inhibitor.Interestingly,ZM323881 also inhibited cell proliferation in the absence of exogenous VEGF,suggestingthat VEGF autocrine plays a role in the proliferation of NSCs.The stimulatory effect of VEGF on NSC proliferationdepends on bFGF,which is likely due to the fact that expression of Flk-1 was upregulated by bFGF via phosphoryla-tion of ERK1/2.Collectively,this study may provide insight into the mechanisms by which mieroenvironmental nichesignals regulate NSCs.  相似文献   
107.
目的 探讨护肝片对中、晚期纤维化大鼠肝组织肝星状细胞(HSC)的活化与增殖及转化生长因子-β1(TGF-β1)及其工型受体(TβRⅠ)表达的影响。方法 采用12.5%CCh诱导的大鼠肝纤维化模型,自造模之日起,大鼠分组灌胃给药(护肝片921mg·kg^-1)或溶媒,每日一次,直至8或13周末,分别处死动物,取左叶肝组织石蜡包埋,制作组织芯片,免疫组化S-P法检测大鼠肝组织α-平滑肌肌动蛋白(α-SMA)、TGF-β1及TβRⅠ蛋白的表达,并用Meta Morph图像分析系统计数α-SMA阳性细胞数、对TGF-β1。及TβRⅠ蛋白表达量进行定量分析。结果 1.模型复制8周和13周,模型组的肝损伤及其纤维化分级均明显高于正常组(P〈0.01),护肝片组的肝损伤及其纤维化分级均轻于模型组。2.模型复制8周和13周,模型组活化的HSC(即α-SMA阳性细胞)数量较正常组明显增多、TGF-β1及TβRⅠ蛋白的表达较正常组明显增强(P〈0.01);3.护肝片显著抑制8、13周纤维化肝组织HSC的活化与增殖和TGF-β1及TβRⅠ蛋白的表达(P〈0.01)。结论 抑制HSC的活化与增殖和TGF-β1及TβRⅠ的表达可能是护肝片抗肝纤维化作用的靶点之一。  相似文献   
108.
To evaluate the characteristics of chicken interleukin-18 (ChIL-18) in different forms in vitro,the ChIL-18 full-length gene (ChIL-18-F) and the ChIL-18 presumed mature protein gene (ChIL-18-M) werecloned and inserted into the eukaryotic expression vector pCI,to construct recombinant pCI-ChIL-18-Fand pCI-ChIL-18-M.The recombinant plasmids were then transferred into chicken splenic lymphocytes(CSLs).Western blot showed that ChIL-18-F,with a molecular weight of 23.0 kDa,was produced in CSLstransfected by pCI-ChlL-18-F;ChIL-18-M,with a molecular weight of 19.5 kDa,was produced in CSLstransfected by pCI-ChIL-18-M.The nitric oxide (NO) level in the transfected CSLs and the culture mediumat different time points was further examined under confocal microscopy using 4.5-diaminofluoresceinstaining.The results showed that both pCI-ChIL-18-F and pCI-ChIL-18-M groups showed significantincrease in intracellular and extracellular NO production compared with pCI transfected control cells.Theseresults suggest that both ChIL-18-F and ChIL-18-M could stimulate NO secretion in CSLs.To characterizethe intracellular distribution of ChIL-18,ChIL-18-F and ChIL-18-M were each fused to the enhanced greenfluorescent protein gene,and expressed in Vero cells.The results showed that the ChIL-18-F tended to themembranous region in Vero cells,while ChIL-18-M did not.This indicates that the N-terminal 27 amino acidpeptide helped ChIL-18 target to Veto cell membranes.  相似文献   
109.
In the 1980s some special protozoa were gradually recognized: being eukaryotes, they possess some characteristics between prokaryotes and eukaryotes, for example, lack of eukaryotic organelle such as mi-tochondria, and even 70S ribosomes in some species, containing 16S, 23S rRNA like those of prokaryotes. These protozoa contain diplomonads (e.g. intestinal parasite Giardia), parabasalids (e.g. venereal disease pathogen Trichomonas), microsporidia (e.g. the human pathogen Encephalitozoon), a…  相似文献   
110.
INTRODUCTION Today, Acquired Immunodeficiency Syndrome (AIDS) has become a public health and social problem that has caused significant harm to the survival and development of humanbeings. Route of transmission of Human Im- munodeficiency Virus (HIV) is still predominantly through shared syringes by drug abusers. Currently, there is no efficient medicine, treatment or educational method to prevent HIV transmission in China. Intervention is prob- ably the best “vaccine” [1]. Despi…  相似文献   
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