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391.
The caveolin gene family has three members in vertebrates: caveolin-1, caveolin-2, and caveolin-3. So far, most caveolin-related research has been conducted in mammals, but the proteins have also been found in other animals, including Xenopus laevis, Fugu rubripes, and Caenorhabditis elegans. Caveolins can serve as protein markers of caveolae ('little caves'), invaginations in the plasma membrane 50-100 nanometers in diameter. Caveolins are found predominantly at the plasma membrane but also in the Golgi, the endoplasmic reticulum, in vesicles, and at cytosolic locations. They are expressed ubiquitously in mammals, but their expression levels vary considerably between tissues. The highest levels of caveolin-1 (also called caveolin, Cav-1 and VIP2I) are found in terminally-differentiated cell types, such as adipocytes, endothelia, smooth muscle cells, and type I pneumocytes. Caveolin-2 (Cav-2) is colocalized and coexpressed with Cav-1 and requires Cav-1 for proper membrane targeting; the Cav-2 gene also maps to the same chromosomal region as Cav-1 (7q31.1 in humans). Caveolin-3 (Cav-3) has greater protein-sequence similarity to Cav-1 than to Cav-2, but it is expressed mainly in muscle cells, including smooth, skeletal, and cardiac myocytes. Caveolins participate in many important cellular processes, including vesicular transport, cholesterol homeostasis, signal transduction, and tumor suppression. 相似文献
392.
Gordana?M?Pavlovi?-La?eti? Nenad?S?Miti?Email author Milo??V?Beljanski 《BMC bioinformatics》2004,5(1):65
Background
We have compared 38 isolates of the SARS-CoV complete genome. The main goal was twofold: first, to analyze and compare nucleotide sequences and to identify positions of single nucleotide polymorphism (SNP), insertions and deletions, and second, to group them according to sequence similarity, eventually pointing to phylogeny of SARS-CoV isolates. The comparison is based on genome polymorphism such as insertions or deletions and the number and positions of SNPs. 相似文献393.
394.
化疗药物的应用是当今治疗恶性肿瘤的主要方法之一。近年来,随着对人体微生物研究的不断深入,肠道菌群在疾病的诊断和治疗中发挥越来越重要的作用。肠道菌群具有调节炎症反应、维持肠道屏障功能稳定和调节免疫反应的作用,其菌株可能作为一种潜在的肿瘤诊断标志物。肠道菌群与化疗药物之间的关系越发紧密,如肠道菌群如何影响化疗药物的作用效果,恶心、呕吐、便秘、骨髓抑制等化疗药物的毒副作用对肠道菌群又有何种影响,应用益生菌后肠道菌群如何变化以及对化疗药物毒副作用有何影响。因此,本文回顾了化疗药物与肠道菌群相互作用研究的进展,希望为国内学者提供肠道菌群和癌症化疗之间关系的理论基础,并为治疗癌症提供新的研究思路。 相似文献
395.
目的考察不同煎煮方法及人工胃液、肠液对栀子豉汤所含优势菌群的影响,基于芽胞杆菌的整肠作用探讨栀子豉汤的作用机制。方法采用先煎栀子再煎淡豆豉(方法一)及两药同时煎煮(方法二)得到不同的栀子豉汤溶液,在营养琼脂培养基上培养及菌落计数,通过Biolog自动微生物鉴定系统对分离菌株进行鉴定,并考察人工胃液、肠液对栀子豉汤所含优势菌群数量的影响。结果方法一制备的栀子豉汤所含优势菌数量更多,为(2.55±0.02)×10~5 CFU/mL,以枯草芽胞杆菌为主;栀子豉汤经人工胃液、人工肠液作用后,优势菌又大量繁殖。结论栀子豉汤可能通过其所含益生芽胞杆菌的整肠作用而发挥药效。 相似文献
396.
Qiang Zhang Sheng li An Zhen yu Chen Feng-Hua Fu Bo Jiang Fa chao Zhi Yang Bai Wei Gong 《PloS one》2014,9(10)
Background and Aim
Delayed colonic postpolypectomy bleeding is the commonest serious complication after polypectomy. This study aimed to utilize massive sampling data of polypectomy to analyze risk factors for delayed postpolypectomy bleeding.Patients and Methods
The endoscopic data of 5600 patients with 15553 polyps removed (2005 to 2013) were analyzed retrospectively through univariate analysis and multiple logistic regression analysis to evaluate the risk factors for delayed bleeding.Results
Delayed postpolypectomy bleeding occurred in 99 polyps (0.6%). The rates of bleeding for different polypectomy methods including hot biopsy forcep, biopsy forcep, Argon Plasma Coagulation (APC), Endoscopy piecemeal mucosal resection (EPMR), Endoscopic Mucosal Resection (EMR), and snare polypectomy were 0.1%, 0.0%, 0.0%, 6.9%, 0.9% and 1.0%, respectively. The risk factors for delayed bleeding were the size of polyps over 10 mm (odds ratio [OR] = 4.6, 95% CI, 2.9–7.2), pathology of colonic polyps (inflammatory/hyperplastic, OR = 1; adenomatous, OR = 1.4, 95% CI, 0.7–2.6; serrated, OR = 1.5, 95% CI, 0.2–11.9; juvenile, OR = 4.3, 95% CI, 1.8–11.0; Peutz-Jegher, OR = 3.3, 95% CI, 1.0–10.7), and immediate postpolypectomy bleeding (OR = 2.9, 95% CI, 1.4–5.9). In addition, although polypectomy method was not a risk factor, compared with hot biopsy forcep, snare polypectomy, EMR, and EPMR had increased risks of delayed bleeding, with ORs of 3.2 (0.4–23.3), 2.8 (0.4–21.7) and 5.1 (0.5–47.7), respectively.Conclusion
Polyp size over 10 mm, pathology of colonic polyps (especially juvenile, Peutz-Jegher), and immediate postpolypectomy bleeding were significant risk factors for delayed postpolypectomy bleeding. 相似文献397.
The taxonomy of two species of Pleuronichthys from East Asia was re-examined on the basis of scale characteristics. The lectotype of Pleuronichthys cornutus (Temminck and Schlegel 1846) was shown to be conspecific with Pleuronichthys japonicus Suzuki, Kawashima and Nakabo 2009, being characterized by oval scales, a greater exposed scale area and lower scale counts than a second species, formerly recognized as P. cornutus, but to which Pleuronichthys lighti Wu 1929, formerly considered a junior synonym of P. cornutus, should now be applied. Accordingly, P. japonicus is now considered a junior synonym of P. cornutus. 相似文献
398.
399.
Development of a novel recessive genetic male sterility system for hybrid seed production in maize and other cross‐pollinating crops 下载免费PDF全文
Yongzhong Wu Tim W. Fox Mary R. Trimnell Lijuan Wang Rui‐ji Xu A. Mark Cigan Gary A. Huffman Carl W. Garnaat Howard Hershey Marc C. Albertsen 《Plant biotechnology journal》2016,14(3):1046-1054
We have developed a novel hybridization platform that utilizes nuclear male sterility to produce hybrids in maize and other cross‐pollinating crops. A key component of this platform is a process termed Seed Production Technology (SPT). This process incorporates a transgenic SPT maintainer line capable of propagating nontransgenic nuclear male‐sterile lines for use as female parents in hybrid production. The maize SPT maintainer line is a homozygous recessive male sterile transformed with a SPT construct containing (i) a complementary wild‐type male fertility gene to restore fertility, (ii) an α‐amylase gene to disrupt pollination and (iii) a seed colour marker gene. The sporophytic wild‐type allele complements the recessive mutation, enabling the development of pollen grains, all of which carry the recessive allele but with only half carrying the SPT transgenes. Pollen grains with the SPT transgenes exhibit starch depletion resulting from expression of α‐amylase and are unable to germinate. Pollen grains that do not carry the SPT transgenes are nontransgenic and are able to fertilize homozygous mutant plants, resulting in nontransgenic male‐sterile progeny for use as female parents. Because transgenic SPT maintainer seeds express a red fluorescent protein, they can be detected and efficiently separated from seeds that do not contain the SPT transgenes by mechanical colour sorting. The SPT process has the potential to replace current approaches to pollen control in commercial maize hybrid seed production. It also has important applications for other cross‐pollinating crops where it can unlock the potential for greater hybrid productivity through expanding the parental germplasm pool. 相似文献
400.
Sasakawa K 《Zoological science》2006,23(7):587-591
A morphological association between genitalia and ejaculates could provide insight into the function and evolution of genitalia. In this study, the morphologies of the ejaculates and male genitalia of 15 species of Pterostichini and two species of Platynini (Coleoptera: Carabidae) are described. All the species examined formed a spermatophore, the morphology of which could be classified into three types based on its relative volume in the female vaginal cavity and the presence or absence of a pluglike conformation. Male genital morphology could be divided into two types by the direction of the endophallus and gonopore. Species with a strongly bent endophallus invariably formed a pluglike spermatophore. The results suggest that the peculiar shape of endophallus found in some species of Pterostichini may function in forming the pluglike structure of the spermatophore. 相似文献