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31.
A sporadic, adult male patient with generalized platyspondyly, large mandible, hypoplastic teeth, strabismus, and low serum cholesterol levels is presented. Some of the patient's features resemble brachyolmia, Spondylo-epiphyseal dysplasia tarda, Kenny-Caffey and Stickler syndromes. Based on literature review, possible diagnoses are discussed. In conclusion, this patient can have a variant of brachyolmia or Spondylo-epiphyseal dysplasia tarda. However, we cannot exclude that this constellation of clinical features may represent a new syndrome.  相似文献   
32.
利用GC-MS联用仪和计算机信息检索法,通过对云南松Pinus yunnanensis树干韧皮部和枝梢的挥发性物质成分的分析发现,二部位所含挥发性物质在组成成分和含量上存在明显差异.云南松树干挥发物以α-蒎烯为主,含量达81.01%,枝梢为挥发物以α-蒎烯和β-水芹烯为主,含量分别达29.20%和30.52%.与云南松...  相似文献   
33.
The activation-induced cytidine deaminase (AID) gene, specifically expressed in germinal center B cells in mice, is a member of the cytidine deaminase family. We herein report mutations in the human counterpart of AID in patients with the autosomal recessive form of hyper-IgM syndrome (HIGM2). Three major abnormalities characterize AID deficiency: (1) the absence of immunoglobulin class switch recombination, (2) the lack of immunoglobulin somatic hypermutations, and (3) lymph node hyperplasia caused by the presence of giant germinal centers. The phenotype observed in HIGM2 patients (and in AID-/- mice) demonstrates the absolute requirement for AID in several crucial steps of B cell terminal differentiation necessary for efficient antibody responses.  相似文献   
34.
通过GC—MS分析,发现健康的与遭受华山松木蠹象Pissodes punctatus Langor et Zhang危害的华山松Pinusarmandii Franch树干以及华山松枝梢释放的挥发性单萜烯在含量上存在较大差别;利用Y-型双向选择嗅觉仪进行的室内趋向反应实验发现,处于补充营养期和交尾产卵期的华山松木蠹象对单萜烯表现出不同的趋向反应。在华山松枝梢挥发物中含量较高的(-)-β-蒎烯、月桂烯和柠檬烯引起补充营养期华山松木蠹象较大的趋向反应;在华山松树干韧皮部挥发物中含量较高的3-(+)-蒈烯则引起交尾产卵期的华山松木蠹象较大的趋向反应。根据试验结果,对华山松和华山松木蠹象互作的机制进行了初步探讨。  相似文献   
35.
在室内测定了陈齿爪鳃金龟Holotrichia cheni Chang成虫对油橄榄、板栗和杨梅新鲜树叶的选择和取食反应。油橄榄与板栗和杨梅比较,陈齿爪鳃金龟显著趋向油橄榄树叶,而板栗与杨梅相比,则显著趋向板栗树叶(P<0.01)。陈齿爪鳃金龟成虫取食油橄榄、板栗、杨梅树叶12h后,平均排粪量分别为(203.0±104.8)mg、(100.6±76.6)mg和(8.0±9.6)mg,差异显著(P<0.05),且雄虫对油橄榄的平均取食量约为雌虫的2倍。油橄榄是陈齿爪鳃金龟的主要寄主。  相似文献   
36.

Background

The present study was conducted in order to evaluate the fatty acid profile, anti-oxidant and anti-bacterial activities from the microwave aqueous extract of the leaves of three different varieties of Labisia pumila Benth.

Results

The chemical analysis of the extract showed that fatty acids (palmitic, palmitoleic, stearic, oleic, linoleic and α-linolenic) acid as the main components in three varieties of L. pumila leaves. Furthermore, the obtained results of the anti-oxidant revealed that L. pumila var. alata contained higher anti-oxidative activities compared to var. pumila and var. lanceolata. However, these values were lower than the tested anti-oxidant standards. On the other hand, the aqueous leaf extracts in all three varieties of L. pumila were also found to inhibit a variable degree of antibacterial activities against eight bacteria (four Gram-positive and four Gram-negative bacteria).

Conclusions

In this study, it was observed the leaves of three varieties of L. pumila exhibited variable patterns of fatty acids and the microwave aqueous extraction possess anti-oxidant and anti-bacterial activities.  相似文献   
37.
以云南省瑞丽市勐秀林场扦插种植的薇甘菊为试材,采用液相色谱串联质谱(LC-MS/MS)技术对花芽未分化期和花序原基分化期花芽中的生长素(IAA)、赤霉素(GA)、脱落酸(ABA)、反式玉米素(tZ)、异戊烯腺嘌呤(IP)、1-氨基环丙烷羧酸(ACC)、茉莉酸(JA)和水杨酸(SA)含量进行定量分析,同时基于转录组基因功能注释数据对内源激素合成、代谢及信号转导途径相关基因进行表达分析,以探讨不同内源激素对薇甘菊花芽形成的调控作用,以及内源激素合成和信号转导途径相关基因调控薇甘菊花芽分化的机制,为后期通过外源激素调控薇甘菊内源激素水平的方式来控制薇甘菊的有性繁殖提供理论和技术支持。结果表明:(1)薇甘菊未分化期花芽中GA15、GA19、GA20、GA24、IAA、ABA和ETH含量低于花序原基分化期,而未分化期花芽中两种细胞分裂素tZ和IP含量显著高于花序原基分化期。(2)基于RNA-seq测序结果,在薇甘菊两个花芽分化时期共获得7 116个差异表达基因(DEGs),其中上调3 907个,下调3 209个。(3)在内源激素合成方面,参与GA15、GA19、GA20、GA24、IAA、ABA和ACC合成的大量DEGs在花序原基分化期上调表达,这与它们在薇甘菊花序原基分化期的高含量趋势相一致;参与IAA合成的YUCCA基因家族和ACC合成的ACS基因在花序原基分化期的高表达也可能参与促进薇甘菊花芽分化。(4)在植物激素转导途径中,在花序原基分化期,生长素信号转导途径通过AUX/IAA(gene-E3N88_07743)的下调表达和ARF(gene-E3N88_41119)的上调表达,乙烯信号转导途径通过ERF(gene-E3N88_41547)的上调表达,赤霉素信号转导途径通过GID1(gene-E3N88_19448)基因的上调表达,细胞分裂素信号转导途径通过B-ARR(gene-E3N88_28086)和A-RRR(gene-E3N88_40764)基因的下调表达,脱落酸途径通过AREB(gene-E3N88_18558)基因的上调表达,茉莉酸信号转导途径通过JAZ(gene-E3N88_05628)的上调表达和MYC2(gene-E3N88_32405)的下调表达来调控薇甘菊花芽分化。研究发现,高水平的GA15、GA19、GA20、GA24、IAA、ABA和ACC有利于薇甘菊的花芽分化;薇甘菊在花芽分化过程中通过改变不同种类内源激素合成、代谢基因的表达来调控激素浓度,而激素又通过信号转导途径引起下游基因的表达,进而调控薇甘菊的花芽分化。  相似文献   
38.
We investigated the effects of naringin on small intestine, liver, kidney and lung recovery after ischemia/reperfusion (I/R) injury of the gut. Rats were divided randomly into four groups of eight. Group A was the sham control; group B was ischemic for 2 h; group C was ischemic for 2 h and re-perfused for 2 h (I/R); group D was treated with 50 mg/kg naringin after ischemia, then re-perfused for 2 h. Endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) expressions were detected by immunolabeling. We also measured arginase activity, amounts of nitric oxide (NO) and total protein. iNOS was increased significantly in the small intestine, liver and kidney in group C. iNOS was decreased significantly only in small intestine and lung in group D. eNOS was increased significantly in the small intestine, liver and lung in group C. eNOS was decreased in small intestine, liver and lung in group D; however, eNOS was decreased in the kidney in group C and increased in the kidney in group D. The amount of NO was decreased significantly in all tissues in group D, but arginase activity was decreased in the small intestine and lung, increased in the kidney and remained unchanged in the liver in group D. The total protein increased in the small intestine and liver in group D, but decreased significantly in the kidney and lung in group D. Naringin had significant, salutary effects on the biochemical parameters of I/R by decreasing the NO level, equilibrating iNOS and eNOS expressions, and decreasing arginase activity.  相似文献   
39.
华山松木蠹象聚集信息素分离鉴定和引诱效果   总被引:2,自引:0,他引:2  
为了研制华山松木蠹象Pissodes punctatus Langor et Zhang的引诱剂,对华山松木蠹象的虫粪和雄虫后肠挥发性物质进行了分析鉴定和室内外生物活性测试。经GC-MS测定,发现在华山松木蠹象的新鲜虫粪和雄虫后肠挥发性物质中,除了松树挥发性的单萜烯如α-蒎烯、β-蒎烯和3-蒈烯以外,还存在1-甲基-2-异丙烯基-环丁烷乙醇(grandisol)。室内Y-型嗅觉仪趋向实验表明,较低浓度的3-(+)-蒈烯、1-甲基-2-异丙烯基-环丁烷乙醇及其相应的醛1-甲基-2-异丙烯基-环丁烷2醛(grandisal),引起华山松木蠹象的正趋向反应。林间引诱试验表明,1-甲基-2-异丙烯基-环丁烷乙醇和1-甲基2-异丙烯基-环丁烷2醛对华山松木蠹象具有一定的引诱作用。由此推断,1-甲基-2-异丙烯基-环丁烷乙醇可能是华山松木蠹象的集结信息素成分之一。  相似文献   
40.
The contribution of CD3gamma to the surface expression, internalization, and intracellular trafficking of the TCR/CD3 complex (TCR) has not been completely defined. However, CD3gamma is believed to be crucial for constitutive as well as for phorbol ester-induced internalization. We have explored TCR dynamics in resting and stimulated mature T lymphocytes derived from two unrelated human congenital CD3gamma-deficient (gamma(-)) individuals. In contrast to gamma(-) mutants of the human T cell line Jurkat, which were selected for their lack of membrane TCR and are therefore constitutively surface TCR negative, these natural gamma(-) T cells constitutively expressed surface TCR, mainly through biosynthesis of new chains other than CD3gamma. However, surface (but not intracellular) TCR expression in these cells was less than wild-type cells, and normal surface expression was clearly CD3gamma-dependent, as it was restored by retroviral transduction of CD3gamma. The reduced surface TCR expression was likely caused by an impaired assembly or membrane transport step during recycling, whereas constitutive internalization and degradation were apparently normal. Ab binding to the mutant TCR, but not phorbol ester treatment, caused its down-modulation from the cell surface, albeit at a slower rate than in normal controls. Kinetic confocal analysis indicated that early ligand-induced endocytosis was impaired. After its complete down-modulation, TCR re-expression was also delayed. The results suggest that CD3gamma contributes to, but is not absolutely required for, the regulation of TCR trafficking in resting and Ag-stimulated mature T lymphocytes. The results also indicate that TCR internalization is regulated differently in each case.  相似文献   
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