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991.
Huihui Chen Leilei Jin Xiaolong Jiang Zhendong Yu Gregory J. Duns Rong Shao Wei Xu Jishuang Chen 《中国病毒学》2014,29(4):257-260
Spartina alterniflora,a coastal saltmarsh plant,has been classified as one of sixteen invasive alien species by the State Environmental Protection Administration of China.Nearly forty years of propagation and intru-sion of this plant has resulted in some harmful effects on the economic development of coastal areas,due to its proliferation. 相似文献
992.
Using amino-labeled oligonucleotide probes, we established a simple, robust and low-noise method for simultaneous detection of RNA and DNA by fluorescence in situ hybridization, a highly useful tool to study the large pool of long non-coding RNAs being identified in the current research. With probes either chemically or biologically synthesized, we demonstrate that the method can be applied to study a wide range of RNA and DNA targets at the single-cell and single-molecule level in cellular contexts. 相似文献
993.
Dylan T. Burnette Lin Shao Carolyn Ott Ana M. Pasapera Robert S. Fischer Michelle A. Baird Christelle Der Loughian Helene Delanoe-Ayari Matthew J. Paszek Michael W. Davidson Eric Betzig Jennifer Lippincott-Schwartz 《The Journal of cell biology》2014,205(1):83-96
How adherent and contractile systems coordinate to promote cell shape changes is unclear. Here, we define a counterbalanced adhesion/contraction model for cell shape control. Live-cell microscopy data showed a crucial role for a contractile meshwork at the top of the cell, which is composed of actin arcs and myosin IIA filaments. The contractile actin meshwork is organized like muscle sarcomeres, with repeating myosin II filaments separated by the actin bundling protein α-actinin, and is mechanically coupled to noncontractile dorsal actin fibers that run from top to bottom in the cell. When the meshwork contracts, it pulls the dorsal fibers away from the substrate. This pulling force is counterbalanced by the dorsal fibers’ attachment to focal adhesions, causing the fibers to bend downward and flattening the cell. This model is likely to be relevant for understanding how cells configure themselves to complex surfaces, protrude into tight spaces, and generate three-dimensional forces on the growth substrate under both healthy and diseased conditions. 相似文献
994.
C.‐N. Tsai W.‐C. Chiang C.‐L. Sun K.‐T. Shao S.‐Y. Chen S.‐Z. Yeh 《Journal of fish biology》2014,84(2):354-371
To examine trophic dynamics over different size classes, an isotopic study of sailfish Istiophorus platypterus life‐history stages was carried out. Samples were collected from eastern Taiwan and the South China Sea during April 2009 and February 2012. A total of 263 samples (111–245 cm, lower jaw fork length, LLJFL) were examined for changes in trophic structure in relation to LLJFL by using stable isotope analysis of carbon (δ13C) and nitrogen (δ15N). The δ15N values for I. platypterus ranged from 7·51 to 14·19‰ (mean ± s.d . = 12·06 ± 1·16‰) and the δ13C values ranged from ?22·04 to ?15·48‰ (mean ± s.d . = ?17·62 ± 1·10‰). The δ15N values were positively dependent on LLJFL (r2 = 0·377), whereas δ13C were negatively dependent on LLJFL (r2 = 0·063). There were significantly different seasonal changes in nitrogen and carbon isotopic concentration, but no significant differences in concentrations between eastern Taiwan and the South China Sea were reported. The trophic level (TL) of each LLJFL class was correlated, starting from 2·84 TL for size class I (LLJFL < 140 cm) and reaching 5·03 TL for size class VI (LLJFL > 221 cm). The mean ± s.d . TL was 4·43 ± 0·19 for all samples. The results reveal that I. platypterus occupies a wide range of trophic levels and different size classes occupy different trophic positions in the pelagic ecosystem. 相似文献
995.
996.
Here, we report a type strain AST-10 representing a novel species Sulfurimonas hongkongensis within Epsilonproteobacteria, which is involved in marine sedimentary sulfur oxidation and denitrification. Strain AST-10T (= DSM 22096T = JCM 18418T) was isolated from the coastal sediment at the Kai Tak Approach Channel connected to Victoria Harbour in Hong Kong. It grew chemolithoautotrophically using thiosulfate, sulfide or hydrogen as the sole electron donor and nitrate as the electron acceptor under anoxic conditions. It was rod-shaped and grew at 15-35°C (optimum at 30°C), pH 6.5-8.5 (optimum at 7.0-7.5), and 10-60 g L-1 NaCl (optimum at 30 g L-1). Genome sequencing and annotation of strain AST-10T showed a 2,302,023 bp genome size, with 34.9% GC content, 2,290 protein-coding genes, and 42 RNA genes, including 3 rRNA genes. 相似文献
997.
998.
999.
三氯化镧脑室注射对下丘脑腹内侧核放电及血清中生长素 … 总被引:3,自引:0,他引:3
目的和方法:将不同剂量三氯化镧LaCl3注射大鼠侧脑室,观察下丘脑腹内侧(VMN)放电频率和血清生长素(GH)含量,研究LaCl3对神经内分泌的影响。结果:小剂量(0.005μmol)注射后可使VMN中GH相关神经元放明显增加,并可引起血清中GH含量的增加;而大剂量LaCl3(0.5μmol)组,VMN放电呈抑制反应,此组动物血清中GH含量呈减少趋势,明显低于小剂量组(P〈0.01),但与生理盐水 相似文献
1000.
Cheng C Qin Y Shao X Wang H Gao Y Cheng M Shen A 《Cellular and molecular neurobiology》2007,27(7):909-921
Mitogen-activated protein kinases (MAPKs) are important mediators of cytokine expression and are critically involved in the
immune response. The lipopolysaccharide (LPS) of gram-negative bacteria induces the expression of cytokines and proinflammatory
genes via the toll-like receptor 4 (TLR4) signaling pathway in diverse cell types. In vivo, Schwann cells (SCs) at the site
of injury may also produce tumor necrosis factor-- α (TNF-α). However, the precise mechanisms of TNF-α synthesis are still
not clear. The purpose of the present study was to elucidate the underlying molecular mechanisms in the cultured SCs for its
ability to activate the MAPKs and TNF-α gene, in response to LPS. Using enzyme-linked immunosorbent assay (ELISA), it was
confirmed that treatment with LPS stimulated the synthesis of TNF-α in a concentration- and time-dependent manner. Intracellular
location of TNF-α was detected under confocal microscope. Moreover, LPS activated extracellular signal-regulated kinase (ERK1/2),
P38 and stress activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) and induced their phosphorylation. LPS-elicited
SCs TNF-α production was also drastically suppressed by PD98059 (ERK inhibitor), SB202190 (P38 inhibitor), or SP600125 (SAPK/JNK
inhibitor). Additionally, the expression of CD14 and TLR4 was examined by RT–PCR. It was demonstrated that the expression
of CD14, TLR4 was crucial for the SCs responses to LPS. In conclusion, the results provide novel mechanisms for the response
of SCs to LPS stimulation, through MAPKs signaling pathways.
Chun Cheng and Yongwei Qin contributed equally to this work. 相似文献