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991.
992.
BACKGROUND: The majority of glomus tumor are small, benign neoplasms that arise from modified smooth muscle cells. They usually occur in the dermis or subcutis of the extremities. However, rare cases have been reported in the visceral locations, most often in the stomach. CASE: A 32-year-old woman presented with episodes of right upper quadrant pain. She was found to have a gastric tumor that was biopsied at another hospital, where the diagnosis of gastrointestinal stromal tumor (GIST) was made. Endoscopic ultrasound (EUS) performed at our institution revealed a gastric submucosal tumor that was then biopsied by fine needle aspiration (FNA). Cytology revealed cohesive clusters of uniform, round, small cells with ill-defined cytoplasmic borders and scanty, amphophilic cytoplasm. Nuclei were round, with smooth nuclear membranes and evenly distributed, dusty chromatin. Intermingled with those epithelioid cells were small, short, spindled, normal endothelial cells. Immunohistochemical studies performed on cell block showed that the tumor cells were negative for CD34, CD117, chromogranin, synaptophysin, desmin and AE1/AE3 and were strongly positive for SMA, HHF-35 and collagen type IV. Glomus tumor was diagnosed and later confirmed by histology. CONCLUSION: EUS-guided FNA biopsy is efficient and permits adequate sampling for accurate diagnosis of gastric glomus tumor. Although rare, glomus tumor should be in the differential diagnosis among other gastric lesions, such as well-differentiated adenocarcinoma, epithelioid GIST and carcinoid tumor. 相似文献
993.
The Hengduan Mountains comprise one of the world's most important hot spots of biodiversity. Tibetia (Ali) H.P. Tsui (Fabaceae), which has four or five species in two sections, is one of the genera endemic to the region. This paper describes for the first time the karyotype of three of those species. The chromosome counts of all three are 2 n = 16. The karyotypes of the species examined contain chromosomes of variable karyotypic symmetry with centromeres at median and submedian positions that correlate with the morphological characteristics of the species. Karyotypic variation at the diploid level appears to be the predominant feature of chromosome evolution in the genus and may provide a clue to the study of evolutionary patterns of plants in this region. 相似文献
994.
发酵活性豆渣饲料的研究 总被引:5,自引:0,他引:5
活性豆渣饲料是新鲜豆渣经微生物发酵而得到的。本文介绍了发酵菌株的筛选过程,并对发酵的最适条件进行了研究。分析结果表明,这种饲料含有蛋白酶等多种酶类,蛋白质、氨基酸的含量均比未发酵的豆渣有所增加,而且克服了豆渣含水量大、易腐败的缺点,有利于畜禽更充分地消化吸收。经动物喂养实验证明.活性豆渣饲料可代替50%以上的鱼粉,是一种非常理想的蛋白饲料。 相似文献
995.
A model of cross-bridge attachment to actin in the A*M*ATP state based on x-ray diffraction from permeabilized rabbit psoas muscle 下载免费PDF全文
A model of cross-bridges binding to actin in the weak binding A*M*ATP state is presented. The modeling was based on the x-ray diffraction patterns from the relaxed skinned rabbit psoas muscle fibers where ATP hydrolysis was inhibited by N-phenylmaleimide treatment (S. Xu, J. Gu, G. Melvin, L. C. Yu. 2002. Biophys. J. 82:2111-2122). Calculations included both the myosin filaments and the actin filaments of the muscle cells, and the binding to actin was assumed to be single headed. To achieve a good fit, considerable flexibility in the orientation of the myosin head and the position of the S1-S2 junction is necessary, such that the myosin head can bind to a nearby actin whereas the tail end was kept in the proximity of the helical track of the myosin filament. Hence, the best-fit model shows that the head binds to actin in a wide range of orientations, and the tail end deviates substantially from its lattice position in the radial direction (approximately 60 A). Surprisingly, the best fit model reveals that the detached head, whose location thus far has remained undetected, seems to be located close to the surface of the myosin filament. Another significant requirement of the best-fit model is that the binding site on actin is near the N terminus of the actin subunit, a position distinct from the putative rigor-binding site. The results support the idea that the essential role played by the weak binding states M*ATP <--> A*M*ATP for force generation lies in its flexibility, because the probability of attachment is greatly increased, compared with the weak binding M*ADP*P(i) <--> A*M*ADP*P(i) states. 相似文献
996.
997.
Taneja P Gu J Peng R Carrick R Uchiumi F Ott RD Gustafson E Podust VN Fanning E 《The Journal of biological chemistry》2002,277(43):40853-40861
A cDNA encoding a human ortholog of mouse DNA helicase B, which may play a role in DNA replication, has been cloned and expressed as a recombinant protein. The predicted human DNA helicase B (HDHB) protein contains conserved helicase motifs (superfamily 1) that are strikingly similar to those of bacterial recD and T4 dda proteins. The HDHB gene is expressed at low levels in liver, spleen, kidney, and brain and at higher levels in testis and thymus. Purified recombinant HDHB hydrolyzed ATP and dATP in the presence of single-stranded DNA, displayed robust 5'-3' DNA helicase activity, and interacted physically and functionally with DNA polymerase alpha-primase. HDHB proteins with mutations in the Walker A or B motif lacked ATPase and helicase activity but retained the ability to interact with DNA polymerase alpha-primase, suggesting that the mutants might be dominant over endogenous HDHB in human cells. When purified HDHB protein was microinjected into the nucleus of cells in early G(1), the mutant proteins inhibited DNA synthesis, whereas the wild type protein had no effect. Injection of wild type or mutant protein into cells at G(1)/S did not prevent DNA synthesis. The results suggest that HDHB function is required for S phase entry. 相似文献
998.
Fayu Yang Xianglian Ge Xiubin He Xiexie Liu Chenchen Zhou Huihui Sun Junsong Zhang Junzhao Zhao Zongming Song Jia Qu Changbao Liu Feng Gu 《遗传学报》2018,45(6):329-332
正CRISPR/Cas9-mediated genome engineering technologies are now widely applied in various organisms,including mouse and human cells(Cong et al.,2013;Mali et al.,2013;Yang et al.,2013;Hsu et al.,2014).The most widely used customized CRISPR/Cas9(Sp Cas9)is derived from Streptococcus pyogenes(Cong et al.,2013).The CRISPR/Cas9 system creates site-specific double- 相似文献
999.
Jun-You Jian Yi-Min Fan Qian Liu Jun Jin Chun-Mao Yuan Wei Gu Zhan-Xing Hu Lie-Jun Huang Xiao-Jiang Hao 《化学与生物多样性》2023,20(2):e202201097
A new quinoline alkaloid, 5-hydroxy-6-methoxy-N-methyl-2-phenylquinoline-4-one ( 1 ), and seventeen known quinoline alkaloids ( 2 – 18 ) were isolated from the roots of Orixa japonica. The structure of 1 was determined by analysis of spectroscopic data. Among them, compounds 2 , 3 , and 13 were isolated from this plant for the first time. All isolates were screened for the anti-pathogenic fungi activities, including Rhizoctonia solani, Magnaporthe oryzae, and Phomopsis sp. The results showed that five compounds ( 4 , 8 , 10 , 11 , and 12 ) exhibited significant anti-pathogenic fungi effects at 50.0 μg/mL. In special, compound 10 exhibited the best antifungal activities toward R. solani and M. oryzae with the IC50 values of 37.86 and 44.72 μM, respectively, better than that of the positive control, hymexazol (IC50 121.21 and 1518.18 μM, respectively). Moreover, eleven new quinoline alkaloids derivatives ( 12a–12k ) were designed and synthesized to investigate the structure−activity relationships (SARs). The SARs analysis indicated that the furo[2,3-b]quinoline skeleton and the methoxy at C-7 (compounds 8 , 11 , and 12 ) played a key role for improving the antifungal activities. 相似文献
1000.
Xiangyu Qin Lingyu Zhou Yaojie Shen Yuwei Gu Jia Tang Junwei Qian An Cui Mingquan Chen 《Journal of cellular and molecular medicine》2023,27(24):4080-4092
Circular RNAs play an important role in the development of various malignancies, including hepatocellular carcinoma (HCC). Nevertheless, the role of Hsa_circ_0093335 (circ0093335) in HCC has not yet been explored. To investigate the biological effects and molecular mechanisms of circ0093335 on HCC. Circ0093335 expression was detected in HCC cells and clinical specimens using qRT-PCR. The association between circ0093335 expression and HCC patients' clinical characteristics was determined using SPSS. The role of circ0093335 in HCC was estimated by overexpression and knockdown experiments in vitro and in vivo. qRT-PCR, nucleoplasma separation assay, FISH assay, RIP, dual luciferase reporter assay and rescue assay were used to validate the regulatory effect of circ0093335 on miR-338-5p. The study findings showed that circ0093335 was upregulated in HCC. High circ0093335 expression was linked with the tumour-node-metastasis stage and microvascular tumour invasion. circ0093335 is greatly involved in HCC cell proliferation, aggressive ability and mouse tumour growth, according to many in vitro and in vivo tests. Mechanistically, circ0093335 downregulated miR-338-5p expression by sponging, consequently promoting HCC progression. Our research indicated that circ0093335 might be a target for HCC therapy since it promotes tumour progression by acting as a miR-338-5p ‘sponge’. 相似文献