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81.
Zhu H Zhou ZM Huo R Huang XY Lu L Lin M Wang LR Zhou YD Li JM Sha JH 《Acta biochimica et biophysica Sinica》2004,36(3):227-234
A gene, presumably involved in spermatogenesis, was identified and characterized by using cDNA microarray. Hybridization intensity was 2.13 fold higher in adult testis than that in fetal testis.The full length of this gene was 4288bp and it encoded a 578 amino acid protein. Conserved structure and amino acid sequence analysis revealed that the protein contained 1 Thif-domain, 2 UBACT-domains,and a functional active site cysteine lay upstream of UBACT domain, all of them also existed in ubiquitin-activating enzyme E1 and E1 like proteins. So we named this gene as a novel ubiquitin-activating enzyme E1 like gene (nUBE1L). Expression profile showed that nUBE1L was predominantly expressed in testis.Comparison of the expression of nUBE1L in different developmental stages of testis indicated that it was highly expressed in adult testis. In conclusion, nUBE1L is a novel human E1 like gene highly expressed inadult testis, which plays key role in ubiquitin system, and accordingly influences spermatogenesis and male fertility. 相似文献
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83.
We report here the cloning and characterization of a novel splicing variant of the human zinc binding alcohol dehydrogenase, domain containing 1 (ZADH1) gene. ZADH1 is localized on chromosome 14q24.2. The cDNA of this splicing variant is 1613 base pairs in length, and encodes a 351-amino acid protein with a putative molecular weight of 38.5 kDa. We named the novel splicing variant ZADH1b. By MTC- panel PCR analysis, it was found that ZADH1b was widely expressed in human tissues. Computer analysis revealed ZADH1 had a potential ADH_zinc_N domain and it had considerable homology with some dehydrogenases. It was speculated that ZADH1 may have definite metabolic roles in vivo as a dehydrogenase. 相似文献
84.
氨基酸微素络合物对水稻的生物效应初探 总被引:8,自引:0,他引:8
为了配制氨基酸金属络合肥,使用其主组分进行初步田间对比试验,结果表明:氨基酸微素络合物能明显提高水稻根系活力,缩短从秧田到大田的适应期,促进植株生长,改善库源关系,增加干粒重和谷秆比,从而有效提高产量。以(FeCuZn)AA2增产效果最好,达21.29%,蘸根及喷施是有效施用方式。 相似文献
85.
We used data on loud duetted and solo songs collected from one habituated polygynous group of black‐crested gibbons (Nomascus concolor jingdongensis) on Mt. Wuliang, Yunnan, to test several hypotheses about the functions of these songs. The major functions proposed for loud gibbon songs include resource defense, mate defense, pairbonding, group cohesion and mate attraction. Duet bouts are generally initiated by adult males, who select the highest trees near to ridges or on steep slopes as singing trees. Such trees facilitate voice transmission and inter‐group communication. Singing trees tended to be located near important food patches and sleeping sites, which supports the resource defense hypothesis. The adult male and two adult females always sang interactively, alternating male phrases with the females' stereotyped great calls, to produce the duets, and females rarely produced great calls if they were more than 30 m from the male. The two females usually produced great calls synchronously during the duet, especially when they were close together. These features support both the mate defense and pairbonding hypotheses. The number of great calls and their degree of synchrony transmit information about spatial relationships and possibly pairbond strength to members to neighboring groups and floating animals. During or after the duet bouts, the adult females and juvenile moved toward to the adult male; and group members maintained a close spatial relationship, which supports the group cohesion hypothesis. Other incidents observed suggest a mate competition role for duets. The adult male always sang when the females started duetting with the subadult male. The subadult male sang solo bouts, but they were not more frequent or longer than bouts initiated by the adult male. Although mate attraction is the likely function of subadult solos, it was not convincingly demonstrated. In conclusion, all hypotheses concerning the function of singing are supported by at least some of the data, and none can be excluded. Am. J. Primatol. 71:539–547, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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87.
Background
Influenza H7N9 and H1N1pdm can cause severe human infections. It is important to investigate the distinguishing clinical features between these two diseases. Several studies have compared the differences in general, however, age and gender adjusted comparisons may be more useful and informative to the health professionals.Methods
A total of 184 severe H1N1pdm patients and 37 severe H7N9 patients from Jiangsu Province were included in this analysis to perform age and gender adjusted comparison of clinical features.Results
After adjusting age and gender, no significant differences in chronic medical conditions or treatment were found between severely ill patients with H7N9 and H1N1pdm. Severely ill patients with H7N9 had significantly longer interval from onset of illness to neuraminidase inhibitor treatment and to death. They were more likely to have complications such as acute respiratory distress syndrome (ARDS), liver and renal dysfunctions, and had a significantly higher risk of death.Conclusion
Our results suggests that age and gender should be adjusted as important confounding factors when comparing the clinical features between severe H7N9 and H1N1pdm patients to avoid any misunderstanding regarding the differences between these two diseases particularly in terms of clinical severity and prognosis. 相似文献88.
Hung-Chun Tung Fa-Yauh Lee Sun-Sang Wang Ming-Hung Tsai Jing-Yi Lee Teh-Ia Huo Hui-Chun Huang Chiao-Lin Chuang Han-Chieh Lin Shou-Dong Lee 《PloS one》2015,10(5)
Splanchnic angiogenesis in liver cirrhosis often leads to complications as gastroesophageal variceal hemorrhage and the treatment efficacy is adversely affected by poor portal-systemic collateral vasoresponsiveness related to nitric oxide (NO). Purinergic receptor subtype P2X7 participates in the modulation of inflammation, angiogenesis, fibrogenesis and vasoresponsiveness, but the relevant influence in cirrhosis is unknown. Common bile duct-ligated (CBDL) or sham-operated Spraque-Dawley rats received brilliant blue G (BBG, a P2X7 antagonist and food additive) or vehicle from the 15th to 28th day after operations, then hemodynamics, mesenteric angiogenesis, portal-systemic shunting, liver fibrosis, and protein expressions of angiogenic and fibrogenic factors were evaluated. The influence of oxidized ATP (oATP, another P2X7 receptor antagonist) on the collateral vasoresponsiveness to arginine vasopressin (AVP) was also surveyed. BBG decreased superior mesenteric artery (SMA) flow, portal-systemic shunting, mesenteric vascular density, and mesenteric protein expressions of vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR2), phospho (p)-VEGFR2, platelet-derived growth factor (PDGF), PDGF receptor beta (PDGFRβ), cyclooxygenase (COX)-1, COX-2, and endothelial NO synthase (eNOS) in CBDL rats. BBG also ameliorated liver fibrosis and down-regulated hepatic interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), PDGF, IL-1β, transforming growth factor-beta (TGF-β), p-extracellular-signal-regulated kinases (ERK), and alpha-smooth muscle actin (α-SMA) expressions in CBDL rats. The collateral vasocontractility to AVP was enhanced by oATP. oATP down-regulated eNOS, inducible NOS (iNOS), VEGF, Akt, p-Akt, and nuclear factor-kappa B (NF-κB) expressions in splenorenal shunt, the most prominent intra-abdominal collateral vessel in rodents. P2X7 antagonism alleviates splanchnic hyperemia, severity of portal-systemic shunting, mesenteric angiogenesis, liver fibrosis, and enhances portal-systemic collateral vasoresponsiveness in cirrhotic rats. P2X7 blockade may be a feasible strategy to control cirrhosis and complications. 相似文献
89.
Xiang-guang Lv Yong-feng Shi Xia Xu Yan-lin Wei Hui-mei Wang Xiao-bo Zhang Jian-li Wu 《PloS one》2015,10(11)
A rice chlorophyll-deficient mutant w67 was isolated from an ethyl methane sulfonate (EMS)–induced IR64 (Oryza sativa L. ssp. indica) mutant bank. The mutant exhibited a distinct yellow-green leaf phenotype in the whole plant growth duration with significantly reduced levels of chlorophyll and carotenoid, impaired chloroplast development and lowered capacity of photosynthesis compared with the wild-type IR64. Expression of a number of genes associated with chlorophyll metabolism, chloroplast biogenesis and photosynthesis was significantly altered in the mutant. Genetic analysis indicated that the yellow-green phenotype was controlled by a single recessive nuclear gene located on the short arm of chromosome 3. Using map-based strategy, the mutation was isolated and predicted to encode a chloroplast signal recognition particle 43 KD protein (cpSRP43) with 388 amino acid residuals. A single base substitution from A to T at position 160 resulted in a premature stop codon. OscpSRP43 was constitutively expressed in various organs with the highest level in the leaf. Functional complementation could rescue the mutant phenotype and subcellular localization showed that the cpSRP43:GFP fusion protein was targeted to the chloroplast. The data suggested that Oryza sativa cpSRP43 (OscpSRP43) was required for the normal development of chloroplasts and photosynthesis in rice. 相似文献
90.
Enterococcus faecalis is a ubiquitous bacterium of the gut that is observed in persistent periradicular infections. Its pathogenicity is associated with biofilm formation and the ability to survive under nutrient-poor (starvation) conditions. However, characteristics of chemical composition of biofilm cells developed by starved E. faecalis cells remain poorly understood. In this study, E. faecalis cells in exponential, stationary, and starvation phases were prepared and separately cultured to form biofilms. Confocal laser scanning microscopy was performed to verify biofilm formation. Raman microscopy was used to investigate the chemical composition of cells within the biofilms. Compared to cells in exponential or stationary phase, starved cells developed biofilms with fewer culturable cells (P?0.05). Raman analysis revealed that cells produced in the biofilms from starved planktonic cells contained more protein and less nucleic acids than either the corresponding planktonic cells or the cells in biofilms from planktonic cells in exponential or stationary phases, suggesting that biofilm-grown cells from the starvation phase were characterized by increased synthesis of proteins and decreased nucleic acids. This study provides an insight into the chemical composition of biofilm cells developed by starved E. faecalis. 相似文献