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871.
Zheyong Huang Yunli Shen Hongmin Zhu Jianfeng Xu Yanan Song Xinying Hu Zhang Shuning Xiangdong Yang Aijun Sun Juying Qian Junbo Ge 《Experimental Animals》2013,62(3):197-203
Cell delivery via the retrograde coronary route boasts less vessel embolism, myocardial
injury, and arrhythmogenicity when compared with those via antegrade coronary
administration or myocardial injection. However, conventional insertion into the coronary
sinus and consequent bleeding complication prevent its application in small animals. To
overcome the complication of bleeding, we described a modified coronary retroinfusion
technique via the jugular vein route in rats with myocardial infarction (MI). A flexible
wire with a bent end was inserted into the left internal jugular vein and advanced slowly
along the left superior vena cava. Under direct vision, the wire was run into the left
cardiac vein by rotating the wire and changing the position of its tip. A fine tube was
then advanced along the wire to the left cardiac vein. This modified technique showed less
lethal hemorrhage than the conventional technique. Retroinfusion via transjugular catheter
enabled efficient fluid or cell dissemination to the majority areas of the free wall of
the left ventricle, covering the infarcted anterior wall. In conclusion, transjugular
cardiac vein catheterization may make retrocoronary infusion a more safe and practical
route for delivering cell, drug, and gene therapy into the infarcted myocardium of
rats. 相似文献
872.
873.
Run-Hui Zhang Runhao Jin Hao Deng Qing-Kun Shen Zhe-Shan Quan Chun-Mei Jin 《The Korean journal of parasitology》2021,59(3):297
Toxoplasma gondii infection is widespread worldwide, not only posing a serious threat to human food safety and animal husbandry, but also endangering human health. The selectivity index was employed to measure anti-T. gondii activity. Hederagenin (HE) exhibited potent anti-T. gondii activity and low cytotoxicity. For this reason, HE was selected for in vivo experiments. HE showed 64.8%±13.1% inhibition for peritoneal tachyzoites in mice, higher than spiramycin 56.8%±6.0%. Biochemical parameters such as alanine aminotransferase, aspartate aminotransferase, glutathione, and malondialdehyde, illustrated that HE was a good inhibitor of T. gondii in vivo. This compound was also effective in relieving T. gondii-induced liver damage. Collectively, it was demonstrated that HE had potential as an anti-T. gondii agent. 相似文献
874.
Cloning and characterization of a phospholipase C-beta isoform from the sea urchin Lytechinus pictus
Calcium is a ubiquitous intracellular signaling molecule controlling a wide array of cellular processes including fertilization and egg activation. The mechanism for triggering intracellular Ca(2+) release in sea urchin eggs during fertilization is the generation of inositol-1,4,5-trisphosphate by phospholipase C (PLC) hydrolysis of phosphatidylinositol-4,5-bisphosphate. Of the five PLC isoforms identified in mammals (beta, gamma, delta, epsilon and zeta), only PLCgamma and PLCdelta have been detected in echinoderms. Here, we provide direct evidence of the presence of a PLCbeta isoform, named suPLCbeta, within sea urchin eggs. The coding sequence was cloned from eggs of Lytechinus pictus and determined to have the greatest degree of homology and identity with the mammalian PLCbeta4. The presence of suPLCbeta within the egg was verified using a specifically generated antibody. The majority of the enzyme is localized in the non-soluble fraction, presumably the plasma membrane of the unfertilized egg. This distribution remains unchanged 1 min postfertilization. Unlike PLCbeta4, suPLCbeta is activated by G protein betagamma subunits, and this activity is Ca(2+)-dependent. In contrast to all known PLCbeta enzymes, suPLCbeta is not activated by Galphaq-GTPgammaS subunit suggesting other protein regulators may be present in sea urchin eggs. 相似文献
875.
A new statistical approach for assessing similarity of species composition with incidence and abundance data 总被引:14,自引:0,他引:14
The classic Jaccard and Sørensen indices of compositional similarity (and other indices that depend upon the same variables) are notoriously sensitive to sample size, especially for assemblages with numerous rare species. Further, because these indices are based solely on presence–absence data, accurate estimators for them are unattainable. We provide a probabilistic derivation for the classic, incidence‐based forms of these indices and extend this approach to formulate new Jaccard‐type or Sørensen‐type indices based on species abundance data. We then propose estimators for these indices that include the effect of unseen shared species, based on either (replicated) incidence‐ or abundance‐based sample data. In sampling simulations, these new estimators prove to be considerably less biased than classic indices when a substantial proportion of species are missing from samples. Based on species‐rich empirical datasets, we show how incorporating the effect of unseen shared species not only increases accuracy but also can change the interpretation of results. 相似文献
876.
Hao Zhang Gen-Xuan Wang Zhu-Xia Shen Xing-Zheng Zhao Mu-Qing Qiu 《Acta Physiologiae Plantarum》2006,28(4):373-379
The allometric relationships for plant daily biomass production rates, different measures of body size (dry weight and length)
and photosynthetic biomass per plant are reported for two mutants of Arabidopsis thaliana (abi1-1, insensitive to ABA; era1-2, hypersensitive to ABA). Scaling relationships, such as daily rate of growth (G) vs body mass (M), plant body length or plant height (L) vs body mass (M), photosynthetic biomass (M
p
) vs non-photosynthetic biomass (M
n
), and daily rate of growth (G) vs. photosynthetic biomass (M
p
) were significantly different in abi1-1 and era1-2. It is implied that the sensitivity to abscisic acid may change the scaling relationships for plant biomass production rate
and body size in Arabidopsis thaliana. Because these scaling relationships are closely related to sensitivity to abscisic acid, they are of importance for phytohormonal
ecology. 相似文献
877.
Tjandra D Wong S Shen W Pulliam B Yu E Esserman L 《Bioinformatics (Oxford, England)》2003,19(14):1844-1845
MOTIVATION: Microarrays are an important research tool for the advancement of basic biological sciences. However this technology has yet to be integrated with clinical decision making. We have implemented an information framework based on the Microarray Gene Expression Markup Language (MAGE-ML) specification. We are using this framework to develop a test-bed integrated database application to identify genomic and imaging markers for diagnosis of breast cancer. RESULTS: We developed extensible software architecture for retrieving data from different microarray databases using MAGE-ML and for combining microarray data with breast cancer image analysis and clinical data for correlation studies. The framework we developed will provide the necessary data integration to move microarray research from basic biological sciences to clinical applications. AVAILABILITY: Open source software will be available from SourceForge (http://sourceforge.net/projects/microsoap/). 相似文献
878.
Fluorescence quenching investigation on the interaction of glutathione‐CdTe/CdS quantum dots with sanguinarine and its analytical application 下载免费PDF全文
Water‐soluble glutathione (GSH)‐capped core/shell CdTe/CdS quantum dots (QDs) were synthesized. In pH 5.4 sodium phosphate buffer medium, the interaction between GSH‐CdTe/CdS QDs and sanguinarine (SA) was investigated by spectroscopic methods, including fluorescence spectroscopy and ultraviolet‐visible absorption spectroscopy. Addition of SA to GSH‐CdTe/CdS QDs results in fluorescence quenching of GSH‐CdTe/CdS QDs. Quenching intensity was in proportion to the concentration of SA in a certain range. Investigation of the quenching mechanism, proved that the fluorescence quenching of GSH‐CdTe/CdS QDs by SA is a result of electron transfer. Based on the quenching of the fluorescence of GSH‐CdTe/CdS QDs by SA, a novel, simple, rapid and specific method for SA determination was proposed. The detection limit for SA was 3.4 ng/mL and the quantitative determination range was 0.2–40.0 µg/mL with a correlation coefficient of 0.9988. The method has been applied to the determination of SA in synthetic samples and fresh urine samples of healthy human with satisfactory results. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
879.
880.