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101.
藻胆蛋白(phycobiliprotein)是蓝藻和红藻藻胆体的组成部分,是光合作用集光复合体的组成部分,一般由α和β亚基构成,每个亚基含1~4个辅基色素,从而使藻胆蛋白具有特定的光谱吸收性质。根据这些吸收光谱性质,可以将藻胆蛋白分为:别藻蓝蛋白(APC)、藻蓝蛋白(PC)和藻红蛋白(PE)等,在某些缺乏PE而有异形胞的蓝藻中存在充当PE天线捕光功能的藻红蓝蛋白(PEC)〔1〕。藻胆蛋白可用于天然食用色素、化妆品色素和制药行业,还可作为免疫检测、荧光显微技术和流式细胞荧光测定法技术方面的荧光探针。特别是本工作研究的层理鞭枝藻(简称M.laminosu… 相似文献
102.
The release of gamma-aminobutyric acid (GABA) in rat dorsolateral striatum was studied using in vivo microdialysis. Dialysis was conducted 2 days after probe implantation in awake, freely moving rats using a modified Ringer solution. Calcium induced a reversible increase in GABA release that was abolished by tetrodotoxin but was only slightly attenuated by a maximally effective dose of pergolide, a D2 receptor agonist. It was thus concluded that pergolide inhibits calcium-stimulated release of GABA presynaptically by a mechanism distinct from that of tetrodotoxin. 相似文献
103.
Membranes of adjacent cells form intercellular junctional complexes to mechanically anchor neighbour cells (anchoring junctions), to seal the paracellular space and to prevent diffusion of integral proteins within the plasma membrane (tight junctions) and to allow cell-to-cell diffusion of small ions and molecules (gap junctions). These different types of specialised plasma membrane microdomains, sharing common adaptor molecules, particularly zonula occludens proteins, frequently present intermingled relationships where the different proteins co-assemble into macromolecular complexes and their expressions are co-ordinately regulated. Proteins forming gap junction channels (connexins, particularly) and proteins fulfilling cell attachment or forming tight junction strands mutually influence expression and functions of one another. 相似文献
104.
Woo HN Baik SH Park JS Gwon AR Yang S Yun YK Jo DG 《Biochemical and biophysical research communications》2011,(1):402-15
Accumulation of amyloid-β (Aβ) is widely accepted as the key instigator of Alzheimer’s disease (AD). The proposed mechanism is that accumulation of Aβ results in inflammatory responses, oxidative damages, neurofibrillary tangles and, subsequently, neuronal/synaptic dysfunction and neuronal loss. Given the critical role of Aβ in the disease process, the proteases that produce this peptide are obvious targets. The goal would be to develop drugs that can inhibit the activity of these targets. Protease inhibitors have proved very effective for treating other disorders such as AIDS and hypertension. Mutations in APP (amyloid-β precursor protein), which flanks the Aβ sequence, cause early-onset familial AD, and evidence has pointed to the APP-to-Aβ conversion as a possible therapeutic target. Therapies aimed at modifying Aβ-related processes aim higher up the cascade and are therefore more likely to be able to alter the progression of the disease. However, it is not yet fully known whether the increases in Aβ levels are merely a result of earlier events that were already causing the disease. 相似文献
105.
Strategic mining of cyanobacterial patents from the USPTO patent database and analysis of their scope and implications 总被引:2,自引:0,他引:2
Patent analysis with the help of the strategic mining of patents from databases is important and useful within the framework
of application-oriented research and its commercialization. In the analysis reported here, we have mined cyanobacterial patents
from the patent database of the United States Patent and Trademark Office (USPTO). In order to make an assessment of the commercial
potentials of cyanobacteria, we conducted the patent search (from 1976 to April 2006) using certain generic terms and the
84 genera of cyanobacteria as keywords. The search was performed in two major ways – searching the abstracts and claims of
the patents cumulatively and searching the entire patent documents by the mode of ‘all fields’ in USPTO. In the abstract-
and claims-based search, 234 patents were obtained after the removal of overlapping patents among the keywords. An additional
31 patents were added following the ‘all fields’ search; these patents were not covered in the search that was based on abstracts
and claims. The entire package of 265 patents, of which 244 were related to cyanobacteria, was then analyzed. Information
derived from these patents identified five major areas of cyanobacterial utilization. Cyanobacteria have been patented as
a source of a wide spectrum of products, for medical, agriculture and environmental applications, for gene-based products,
for methods of cultivation and for methods of control. The chronological development in granting cyanobacterial patents was
also traced. This study demonstrates that such strategic mining and analysis of patent data can be used as an index for future
development. 相似文献
106.
O. I. Kiselev V. M. Blinov M. M. Pisareva V. A. Ternovoy A. P. Agafonov D. V. Saraev M. Ju. Eropkin T. G. Lobova V. A. Grigorieva M. P. Grudinin 《Molecular Biology》2008,42(1):70-78
In the second half of 2005, a large-scale outbreak of influenza in poultry and wild birds was caused by a highly pathogenic H5N1 influenza virus in Russia. The level of pathogenicity is a polygenic trait, and most individual genes contribute to the influenza A virus pathogenicity in birds, animals, and humans. The full-length nucleotide sequences were determined for H5N1 strains isolated in the Kurgan region (Western Siberia). The structure of viral proteins was analyzed using the deduced amino acid sequences. The receptor-binding site of hemagglutinin (HA) in strains A/chicken/Kurgan/05/2005 and A/duck/Kurgan/08/2005 was typical for avian influenza viruses and contained Glu and Gly at positions 226 and 228, respectively. The structure of the basic amino acid cluster located within the HA cleavage site was identical in all isolates: QGERRRKKR. According to the neuraminidase structure, all H5N1 isolates from the Kurgan region were assigned to the Z genotype. Amino acid residues typical for the avian influenza virus were revealed in 30 out of 32 positions of M1, M2, NP, PA, and PB2, determining the host range specificity. One of the strains contained Lys at position 627 of PB2. Isolates from the Kurgan region were shown to have a remantadine-sensitive genotype. Both strains contained Glu at position 92 of NS1, indicating that the virus is interferon-resistant. Phylogenetic analysis related the Kurgan isolates to subclade 2 of clade 2 of highly pathogenic H5N1 influenza viruses. 相似文献
107.
Sébastien Lavoué Kouji Nakayama Dean R. Jerry Yusuke Yamanoue Naoki Yagishita Nobuaki Suzuki Mutsumi Nishida Masaki Miya 《Gene》2014
Delineation of the fish family Percichthyidae (Percomorphaceae) has a long and convoluted history, with recent morphological-based studies restricting species members to South American and Australian freshwater and catadromous temperate perches. Four recent nuclear gene-based phylogenetic studies, however, found that the Percichthyidae was not monophyletic and was nested within a newly discovered inter-familial clade of Percomorphaceae, the Centrarchiformes, which comprises the Centrarchidae and 12 other families. Here, we reexamined the systematics of the Percichthyidae and Centrarchiformes based on new mitogenomic information. Our mitogenomic results are globally congruent with the recent nuclear gene-based studies although the overall amount of phylogenetic signal of the mitogenome is lower. They do not support the monophyly of the Percichthyidae, because the catadromous genus Percalates is not exclusively related to the freshwater percichthyids. The Percichthyidae (minus Percalates) and Percalates belong to a larger clade, equivalent to the Centrarchiformes, but their respective sister groups are unresolved. Because all recent analyses recover a monophyletic Centrarchiformes but with substantially different intra-relationships, we performed a simultaneous analysis for a character set combining the mitogenome and 19 nuclear genes previously published, for 22 centrarchiform taxa. This analysis furthermore indicates that the Centrarchiformes are divided into three lineages and the superfamily Cirrhitoidea is monophyletic as well as the temperate and freshwater centrarchiform perch-like fishes. It also clarifies some of the relationships within the freshwater Percichthyidae. 相似文献
108.
摘要 目的:探讨血清膜联蛋白(ANX)A2、ANXA3与转移性结直肠癌(mCRC)患者化疗疗效的关系。方法:选取2019年1月~2020年10月徐州医科大学附属医院收治的90例mCRC患者,根据mFOLFOX6化疗联合西妥昔单抗治疗后的疗效分为未缓解组和缓解组。采用酶联免疫吸附法检测血清ANXA2、ANXA3水平。分别采用单因素、多因素Logistic回归分析和受试者工作特征(ROC)曲线分析mCRC患者化疗未缓解的影响因素和血清ANXA2、ANXA3对mCRC患者化疗未缓解的预测价值。结果:90例mCRC患者客观缓解率为58.89%(53/90)。单因素分析显示,两组年龄、回盲部肿瘤、TNM分期、Zubrod-东部肿瘤协助组-世界卫生组织(ZPS)评分、治疗目标、ANXA2、ANXA3组间比较存在统计学差异(P<0.05)。多因素Logistic回归分析显示,回盲部肿瘤、TNM分期Ⅳ期、ZPS评分1~2分和ANXA2、ANXA3升高为mCRC患者化疗未缓解的独立危险因素(P<0.05)。ROC曲线分析显示,血清ANXA2预测mCRC患者化疗未缓解的曲线下面积(AUC)为0.787,ANXA3预测mCRC患者化疗未缓解的AUC为0.791,血清ANXA2、ANXA3联合预测为0.904,二者联合预测的AUC最大(P<0.05)。结论:血清ANXA2、ANXA3水平升高为mCRC患者化疗未缓解的独立危险因素,可影响mCRC患者的化疗疗效,二者联合预测mCRC患者化疗未缓解的价值较高。 相似文献
109.
V.B. Awasthi 《Journal of insect physiology》1976,22(9):1181-1186
The ultrastructure of the retrocerebral endocrine-aortal complex of the earwig, Euborellia annulipes has been studied. The space between the inner and outer stromal layers of the aorta is occupied by numerous axon terminals and pre-terminals containing large electron dense granules (NS-I) of approximately 100 to 220 nm and a few axon terminals having small granules (NS-II) of approximately 40 to 90 nm; the former appear to belong to medial neurosecretory A-cells, and the latter to the B-cells of the brain. The corpora cardiaca consist of intrinsic cells with mitochondria and multivesicular bodies. Granules of type NS-II and NS-III are observed in the axon terminals and pre-terminals in the corpora cardiaca. The NS-II are identical to those found in the aorta and are probably the secretions of the lateral B-cells. Granules of type NS-III are 40 to 120 nm and electron dense, and are intrinsic in origin. Similar granules occur in the intrinsic cells of the corpora cardiaca. E M studies have confirmed the rôle of the aorta as a neurohaemal organ for the medial neurosecretory cells, and the corpora cardiaca for the lateral neurosecretory cells of the brain. The corpora cardiaca also act as a reservoir for the intrinsic secretion. The corpus allatum is a solid body consisting of parenchymal cells with prominent nuclei, mitochondria, and endoplasmic reticulum. In between its cells are occasional glial cells and also neurosecretory as well as non-neurosecretory axons. The gland is devoid of A-cell NSM. 相似文献
110.
Zhang?Lijuan Jifu?Liu Hao?Zhang Shanshan?Wu Lingyun?Huang Dacheng?He Xueyuan?XiaoEmail author 《中国科学C辑(英文版)》2005,48(6):641-647
There are multiple reports of autoimmune response in patients with lung cancer. To investigate whether a novel autoantibody
is present in patients with lung cancer and evaluate its clinical diagnostic and prognostic value, sera from 10 patients with
lung cancer and 10 normal individuals were analyzed using immunofluorescence and Western blotting. It was found that one serum
sample from the patients with squamous carcinoma gave a fine speckled pattern staining in nucleus and had a high titer antinuclear
autoantibody which could recognize 31 kD of nuclear protein isolated from both cancer cells and normal cells. The same patient’s
serum was further used to immunoprecipitate the target antigen. The protein bands were excised from the SDS-PAGE gels and
were analyzed with a Qstar Pulser I Quadrupole time-flight mass spectrometer, and the 31 kD target antigen was identified
as U1-AsnRNP. To test the prevalence of anti-U1-AsnRNP antibody, sera from 93 patients including 36 squmaous carcinomas (SCC),
26 adenocarcinomas (Ad), and 31 small cell carcinomas (SCLC) were screened by Western blotting. The results demonstrated that
anti-U1-A snRNP antibody was present in 50% of SCC sera, 26.9% of Ad sera and 54.8% of SCLC sera. In this paper, we report
for the first time that anti-U1-AsnRNP antibody could be detected in the patients with lung cancer. 相似文献