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991.
目的对视网膜锥体细胞退行性变(retinal cone degeneration,RCD)大鼠的主要脏器及血液、生化指标进行检测。方法随机选择BN(Brown Norway)-RCDF2代大鼠,视网膜电图鉴定,取静脉血检测生化指标,并对重要脏器进行准确称量。结果此大鼠脏器质量在雌雄之间除体重、大脑和肾差异有显著性外(P〈0.05),其余均无差异;脏器系数脑干和小脑雌性显著大于雄性(P〈0.01);生化指标碱性磷酸酶、葡萄糖、白蛋白、尿素氮、总蛋白雌性高于雄性,总胆固醇、天冬氨酸转氨酶、丙氨酸转氨酶、甘油三酯雌性低于雄性,其中雌性碱性磷酸酶活性显著高于雄性;雌性离子钙浓度显著高于雄性。结论BN-RCD大鼠基础生理值和生化参数均在正常范围内,其中一些参数在性别之间有差异,但与正常SD大鼠相比,天冬氨酸转氨酶、丙氨酸转氨酶、肌酐、钾离子差异显著,葡萄糖、甘油三酯、离子钙有差异。RCD大鼠为遗传性视网膜疾病的研究提供了一种新的突变模式动物。 相似文献
992.
Probabilistic Inference of Biochemical Reactions in Microbial Communities from Metagenomic Sequences
Shotgun metagenomics has been applied to the studies of the functionality of various microbial communities. As a critical analysis step in these studies, biological pathways are reconstructed based on the genes predicted from metagenomic shotgun sequences. Pathway reconstruction provides insights into the functionality of a microbial community and can be used for comparing multiple microbial communities. The utilization of pathway reconstruction, however, can be jeopardized because of imperfect functional annotation of genes, and ambiguity in the assignment of predicted enzymes to biochemical reactions (e.g., some enzymes are involved in multiple biochemical reactions). Considering that metabolic functions in a microbial community are carried out by many enzymes in a collaborative manner, we present a probabilistic sampling approach to profiling functional content in a metagenomic dataset, by sampling functions of catalytically promiscuous enzymes within the context of the entire metabolic network defined by the annotated metagenome. We test our approach on metagenomic datasets from environmental and human-associated microbial communities. The results show that our approach provides a more accurate representation of the metabolic activities encoded in a metagenome, and thus improves the comparative analysis of multiple microbial communities. In addition, our approach reports likelihood scores of putative reactions, which can be used to identify important reactions and metabolic pathways that reflect the environmental adaptation of the microbial communities. Source code for sampling metabolic networks is available online at http://omics.informatics.indiana.edu/mg/MetaNetSam/. 相似文献
993.
人多肽链延伸因子1α基因EEF1A是一个在蛋白质合成过程中起重要作用的看家基因。通过对已有GenBank、GDB等数据库的综合分析,鉴别了4个人类多肽链延伸因子1α基因的反转录假基因,并分别将其精细定位于4q2 5、7p15-21、9q34和19q13上。
Abstract:The gene for human polypeptide chain elongation factor-1α(EEF1A)is a house-keeping gene which plays an important role in the process of protein synthesis.By means of comprehensive analysis in the database of Genbank,GDB and ect,we identify 4 retropseudogenes of EEF1A and finely localized to 4q25,7p15-21,9q34 and 19q13,respectively. 相似文献
994.
目的:目前布氏杆菌性脑膜炎在国内只是偶见报道,本文报道2例布氏杆菌性脑膜炎,对其诊断及治疗进行探讨,并对布氏杆菌脑膜炎进行文献回顾.方法:我们近期连续通过检查脑脊液内布氏杆菌抗体的办法诊断了2例布氏杆菌性脑膜炎,并通过给予四环素、利福霉素及链霉素治疗1个月并通过随访.结果:半年后脑脊液内布氏杆菌抗体恢复阴性,临床症状完全消失.结论:通过我们的观察应用上述3联药物综合治疗1月对布氏杆菌性脑膜炎是有效的. 相似文献
995.
Yuefei Jin Chao Zhang Rongguang Zhang Jingchao Ren Shuaiyin Chen Meili Sui Guangyuan Zhou Dejian Dang Jiehui Zhu Huifen Feng Yuanlin Xi Haiyan Yang Guangcai Duan 《Virology journal》2017,14(1):243
Background
Enterovirus (EV) infection has been a serious health issue in Asia-Pacific region. It has been indicated that the occurrence of fatal hand foot and mouth disease (HFMD) cases following EV71 infection is mainly attributed to pulmonary edema. However, the development of pulmonary disorders after EV71 infection remains largely unknown. To establish an EV71-infected animal model and further explore the underlying association of central nervous system (CNS) invasion with pulmonary edema, we isolated a clinical source EV71 strain (ZZ1350) from a severe case in Henan Province.Methods
We evaluated the cytotoxicity of ZZ1350 strain and the susceptibility in 3-day-old BALB/c mice with intraperitoneal, intracerebral and intramuscular inoculation. Various histopathological and immunohistochemical techniques were applied to determine the target organs or tissue damage after infection. Correlation analysis was used to identify the relationship between CNS injury and pulmonary disorders.Results
Our experimental results suggested that ZZ1350 (C4 subtype) had high cytotoxicity against African green monkey kidney (Vero) cells and human rhabdomyosarcoma (RD) cells and neonatal BALB/c mice were highly susceptible to the infection with ZZ1350 through three different inoculation routes (2?×?106 pfu/mouse) exhibiting severe neurological and respiratory symptoms that were similar to clinical observation. Viral replication was found in brain, spinal cord, skeletal muscle, lung, spleen, liver, heart of infected mice and these sections also showed histopathological changes. We found that brain histology score was positive correlated with lung histology score in total experimental mice and mice under the three inoculation routes (P?<?0.05). At the same time, there were positive correlations between spinal cord score and lung score in total experimental mice and mice with intracerebral inoculation (P?<?0.05).Conclusions
ZZ1350 strain is effective to establish animal model of EV71 infection with severe neurological and respiratory symptoms. The development of pulmonary disorders after EV71 infection is associated with severity of CNS damage.996.
T1alpha/podoplanin deficiency disrupts normal lymphatic vasculature formation and causes lymphedema 总被引:25,自引:0,他引:25
Schacht V Ramirez MI Hong YK Hirakawa S Feng D Harvey N Williams M Dvorak AM Dvorak HF Oliver G Detmar M 《The EMBO journal》2003,22(14):3546-3556
Within the vascular system, the mucin-type transmembrane glycoprotein T1alpha/podoplanin is predominantly expressed by lymphatic endothelium, and recent studies have shown that it is regulated by the lymphatic-specific homeobox gene Prox1. In this study, we examined the role of T1alpha/podoplanin in vascular development and the effects of gene disruption in mice. T1alpha/podoplanin is first expressed at around E11.0 in Prox1-positive lymphatic progenitor cells, with predominant localization in the luminal plasma membrane of lymphatic endothelial cells during later development. T1alpha/podoplanin(-/-) mice die at birth due to respiratory failure and have defects in lymphatic, but not blood vessel pattern formation. These defects are associated with diminished lymphatic transport, congenital lymphedema and dilation of lymphatic vessels. T1alpha/podoplanin is also expressed in the basal epidermis of newborn wild-type mice, but gene disruption did not alter epidermal differentiation. Studies in cultured endothelial cells indicate that T1alpha/podoplanin promotes cell adhesion, migration and tube formation, whereas small interfering RNA-mediated inhibition of T1alpha/podoplanin expression decreased lymphatic endothelial cell adhesion. These data identify T1alpha/podoplanin as a novel critical player that regulates different key aspects of lymphatic vasculature formation. 相似文献
997.
In this paper, the differences between reinforced sequencing batch reactor, which was inoculated with superior mixed flora, and conventional sequencing batch reactor were compared in the process of treating papermaking wastewater under similar conditions. The results showed that the addition of superior mixed flora could not only shorten the sludge acclimation time, but also improve the treatment efficiency of reactor as well as make the reactor have higher ability to withstand high volume loading rate; the phenomenon of aerobic granulation only occurred in reinforced sequencing batch reactor, and superior mixed flora were the key reason that aerobic granular sludge could shape; aerobic granular sludge had many advantages over conventional activated sludge such as it possessed compacter microbial structure, better settling performance, and lower water content. 相似文献
998.
Tang X Gao J Chen J Fang F Wang Y Dou H Xu Q Qian Z 《Biochemical and biophysical research communications》2005,337(1):320-324
The possible inhibition by [corrected] ursolic acid (UA) of [corrected] mitochondrial permeability transition (MPT) in mouse liver was investigated to identify the mechanisms underlying the hepatoprotective effect of UA. The effect of UA on liver MPT induced by Ca2+ was assessed by measuring changes in mitochondrial volume, mitochondrial membrane potential (MMP), release of matrix Ca2+, and transfer of cytochrome c (Cyt c) and apoptosis-inducing factor (AIF) from the intermembrane space to the cytoplasm. The results showed that obvious mitochondrial swelling, loss of MMP, and release of matrix Ca2+ occurred after the addition of 50 microM Ca2+. However, preincubation with 20, 50 or 100 microg ml(-1) UA significantly blocked the above changes. Addition of 100 microg ml(-1) UA inhibited on mitochondrial swelling by 73.2% after 5 min, while the MMP dissipating and Ca2+ releasing were, respectively, suppressed by 59.3% and 54.1% after 3 min. In addition, Western blot analysis showed Cyt c and AIF transferred from mitochondrial pellet to the supernatant after the addition of 50 microM Ca2+, but the process was significantly inhibited by various concentrations of UA. The results suggest that the mechanisms underlying the hepatoprotection of UA may be related to its direct inhibitory action on MPT. 相似文献
999.
在江苏省主要西/甜瓜产区,采集不同种植年限的西/甜瓜农田土壤,采用线虫形态学的鉴定方法,分析了不同种植年限西/甜瓜农田土壤线虫的数量、群落结构及相关生态指数的变化。结果表明:所有调查样点中,共发现土壤线虫54属,平均682条·100 g-1干土,其中原杆属线虫、拟丽突属线虫和矮化属线虫在不同种植年限的西/甜瓜农田土壤中均为优势属;随着种植年限的增加,土壤线虫的总数量虽无显著变化,但其中食细菌类线虫和杂食-捕食类线虫数量显著减少,而植物寄生类线虫数量显著增加;植物寄生类线虫中的矮化属、根结属线虫数量不断增加;随着种植年限的增加,土壤线虫的多样性指数(H)、瓦斯乐斯卡指数(WI)、自由生活线虫成熟度指数(MI)显著降低,线虫通道指数(NCR)、植物寄生线虫成熟度指数(PPI)、PPI/MI显著升高,其他指数无显著变化;相关性分析结果显示,土壤线虫数量与土壤pH、速效磷、有效锌和有效硼均呈显著正相关;土壤p H、有机质、全氮、速效钾、有效硼和有效锌对土壤优势属线虫的影响较大;连续种植西/甜瓜会增加土壤植物寄生类线虫数量,进而可能造成西/甜瓜连作障碍的发生;连续种植6~1... 相似文献
1000.
目的:了解泰山沙参属植物资源现状,测定其根中脂肪、蛋白质及多糖的含量,为合理开发利用泰山沙参属植物资源提供依据。方法:采用野外实地调查法进行资源考察;分别用索氏提取法、考马斯亮蓝法和苯酚-硫酸法测定脂肪、蛋白质和多糖的含量。结果:采集的100余份标本,经鉴定为沙参属植物狭叶沙参[Adenophora gmeli-nii(Spreng)Fisch.]、石沙参(Adenophora polyantha Nakai)、杏叶沙参(Adenophora stricta Mig.)及细叶沙参(Adeno-phora paniculata Nannf.)。泰山沙参属植物狭叶沙参、石沙参、杏叶沙参和细叶沙参脂肪含量分别为2.14%~7.34%,4.27%~7.72%1,.54%~2.51%和4.98%。蛋白质含量分别为0.60~2.10 mg/g0,.80~1.89 mg/g,0.83~0.89 mg/g和1.05 mg/g,多糖含量分别为20.58%~63.21%2,7.74%~65.14%,43.14%~48.47%和45.60%。结论:泰山野生沙参属植物资源丰富,品种多、分布广、蕴藏量大,多糖含量较高,具有较大的开发前景。 相似文献