转类性质的历史演变

《修辞学发凡》立有转类一格,所列例句以古为主兼及今例,我们以转类的主体名词转类为观察对象发现:转类在不同的时代有不同的性质。 先秦两汉的转类是社会的常规用法,不能看作辞格。 “转类”辞格的基础是立足于词语的变异。立足于对规范的有意突破。即如陈先生所说:“修辞上有意从这一类转成别一个类来取……”而实质上,先秦两汉的转类多带社会性,是全社会通行的、被全社会也被个人多次重复的用法。试看下列词的用法:

论英语多词动词的特性

多词动词是英语中一种特殊的词类。在词汇、语法、语义等方面 ,它具有独特的语言特征。这些特征包括多词性、整体性、多义性。

Characterization of Energy_Transduction in Thermal Pretreated Chloroplast from Spinach

Characterization of energy-transduction on die chloroplast thylakoid membranes from spinach (Spinacia oleracca L.) after thermal pretreatment was investigated. The related reactions of energy-transduction in chloroplasts were seriously affected by thermal pretreatment. The results were obtained as following: (1) The rate of cyclic photophosphorylation declined when the pretreatment temperature increased in the range of 25 to 45 degreesC. (2) The thermal pretreatment led to a decrease of the activity of thylakoid membrane-bounded ATPase. (3) Proton uptake of chloroplasts acid the fluorescence quenching of 9-aminoacridine (9-AA) in thylakoid membrane decreased after the thermal pretreatment, but addition of dicyclohexylcarbodiimide (DCCD) could partially restore the fluorescence quenching of 9-AA. (4) Both the rates of fast phase in electrochroism absorption change at 515 nm and the millisecond delayed light emission (ms-DLE) of chloroplast showed a progressive decrease upon raising the temperature of pretreatment. (5) Immunbloting analysis showed that the thermal pretreatment caused the changes of protein content and the electrophoresis mobility of thylakoid membrane-bound ATPase and its alpha -subunit. (6) If the temperature of pretreatment were higher than 33 degreesC, oxygen uptake of PS I -mediated in the samples was rapidly inhibited, but addition of sinapine into the reaction medium could partially restore the ability of oxygen uptake in the samples. These results are briefly discussed in relation to the change of permeability of thylakoid membranes, the dissociation of coupling factor complex as well as accumulation of the radicals in the thylakoid membranes after thermal pretreatment.

Enhancing the photocatalytic activity and photostability of zinc oxide nanorod arrays via graphitic carbon mediation

Low optical absorption and photocorrosion are two crucial issues limiting the practical applications of zinc oxide(ZnO)-based photocatalysts.In this paper,we report the fabrication of graphitic-carbon-mediated ZnO nanorod arrays(NRAs)with enhanced photocatalytic activity and photostability for CO2 reduction under visible light irradiation.ZnO NRA/C-x(x=005,01,02,and 03)nanohybrids are prepared by calcining pre-synthesized ZnO NRAs with different amounts of glucose(0.05,0.1,0.2,and 0.3 g)as a carbon source via a hydrothermal method.X-ray photoelectron spectroscopy reveals that the obtained ZnO NRA/C-x nanohybrids are imparted with the effects of both carbon doping and carbon coating,as evidenced by the detected C-O-Zn bond and the C-C,C-O and C=O bonds,respectively.While the basic structure of ZnO remains unchanged,the UV-Vis absorption spectra show increased absorbance owing to the carbon doping effect in the ZnO NRA/C-x nanohybrids.The photoluminescence(PL)intensities of ZnO NRA/C-x nanohybrids are lower than that of bare ZnO NRA,indicating that the graphitic carbon layer coated on the surface of the ZnO NRA significantly enhances the charge carrier separation and transport,which in turn enhances the photoelectrochemical property and photocatalytic activity of the ZnO NRA/C-x nanohybrids for CO2 reduction.More importantly,a long-term reaction of photocatalytic CO2 reduction demonstrates that the photostability of ZnO NRA/C-x nanohybrids is significantly increased in comparison with the bare ZnO NRA.

Human endogenous retroviruses and cancer

Human endogenous retroviruses(HERVs) are retroviruses that infected human genome millions of years ago and have persisted throughout human evolution. About 8% of our genome is composed of HERVs, most of which are nonfunctional because of epigenetic control or deactivating mutations. However, a correlation between HERVs and human cancer has been described and many tumors, such as melanoma, breast cancer, germ cell tumors, renal cancer or ovarian cancer, express HERV proteins, mainly HERV-K(HML6) and HERV-K(HML2). Although the causative role of HERVs in cancer is controversial, data from animal models demonstrated that endogenous retroviruses are potentially oncogenic. HERV protein expression in human cells generates an immune response by activating innate and adaptive immunities. Some HERV-derived peptides have antigenic properties. For example, HERV-K(HML-6) encodes the HER-K MEL peptide recognized by CD8+ lymphocytes. In addition, HERVs are twoedged immunomodulators. HERVs show immunosuppressive activity. The presence of genomic retroviral elements in host-cell cytosol may activate an interferon type I response. Therefore, targeting HERVs through cellular vaccines or immunomodulatory drugs combined with checkpoint inhibitors is attracting interest because they could be active in human tumors.

Human endogenous retroviruses and cancer:Causality and therapeutic possibilities

A substantial part of the human genome is derived from transposable elements;remnants of ancient retroviral infections.Conservative estimates set the percentage of human endogenous retroviruses(HERVs) in the genome at 8%.For the most part,the interplay between mutations,epigenetic mechanisms and posttranscriptional regulations silence HERVs in somatic cells.We first highlight mechanisms by which activation of members of several HERV families may be associated with tumor development before discussing the arising chances for both diagnosis and therapy.It has been shown that at least in some cases,tumor cells expressing HERV open reading frames(ORFs) thus gain tumor-promoting functions.However,since these proteins are not expressed in healthy tissues,they become prime target structures.Of potential pharmacological interest are the prevention of HERV transposition,the inhibition of HERV-encoded protein expression and the interference with these proteins' activities.Evidence from recent studies unequivocally proves that HERV ORFs represent a very interesting source of novel tumor-specific antigens with even the potential to surpass entity boundaries.The development of new tumor(immune-) therapies is a very active field and true tumor-specific targets are of outstanding interest since they minimize the risk of autoimmunity and could reduce side effects.Finally,we postulate on main future research streams in order to stimulate discussion on this hot topic.

The efficacy and its related issues of combination of bevacizumab and taxanes-based regimens in Chinese patients with metastatic breast cancer

Objective: Bevacizumab has been challenging in the treatment of metastatic breast cancer. To investigate its efficacy, optimal partner to combine with and maintenance therapy, we performed a retrospective study based on Chinese patients with metastatic breast cancer (MBC). Methods: Patients with MBC treated with bevacizumab-contained regimens at the Sun Yat-sen University Cancer Center from 2006 to 2010 were recruited to the study. The primary endpoints were overall survival (OS), time to progression (TTP), objective response rate (ORR), and disease control rate (DCR). These endpoints were analyzed using the Kaplan-Meier and Chi-squared tests, respectively. Results: (1) A total of 229 cycles of bevacizumab with a median cycle of 7 (1-34) were administered among 25 patients. (2) In the whole group, ORR and DCR were 60% (15/25) and 76% (19/25), respectively. The mTTP was 5 months (1-21), mOS from diagnosis was 48 months (13-172), mOS from bevacizumab administration was 24 months (1-45). (3) Both ORR (73.7% vs. 16.7%, P = 0.023) and DCR (94.7% vs. 33.3%, P = 0.005) were significant higher once patients treated with the combination of taxanes-based regimen and bevacizamab when compared with the combination with non-taxanes-based regimens. (4) In the taxanes-based group, no matter bevacizumab used in first line or non-first line, the differences of ORR (P = 0.637) and DCR (P = 0.316) were insignificant. However, the maintenance therapy with bevacizumab will bring more longer TTP (P < 0.001) than those without maintenance therapy. Conclusion: Taxanes-based regimens were the optimal candidate to combine with bevacizumab regardless the timing in palliative setting, however, the maintenance therapy with bevacizumab should be considered once indicated.

Different Kinds of Discrete Breathers in Three Types of One-Dimensional Models

The dynamics of different kinds of discrete breathers in three types of one-dimensionai monatomic chains with on-site and inter-site potentiais are investigated. The existence and evolution of symmetric breather, antisymmetric breather, and multibreather in one-dimensionai models are proved by using rotating wave approximation, local anharmonic approximation, and the numerical method. The linear stability of these breathers is investigated by using Lyapunov stable anaiysis. The localization and stability of breathers in three types of models correlate closely to the system nonlinear parameter β.

Effects of Surfactant on Solubility and Microbial Conversion of Steroid

Enhancing the dispersion and dissolution of substrate particles in substrate water suspension is a feasible way to improve steroid bioconversion. The aim of the present study is to investigate the effects of applying surfactant to microbial conversion system on the dispersion, solubilization and in turn bioconversion of steroid substrate. The model system is hydroxylation of substrate 19α- 17α-epoxy- 4-pregnene- 3.2It-dine by microbial enzymes from Rhizopus nigricanl. The results show that the presence of substrate leads to an increase in critical micelle concentration （ CMC） of surfactant PSE compared with the normal CMC of PSE in aqueous solution. The grinding time during substrate suspension preparation affects the substrate aqueous solubility differently with the varied surfactant concentrations while barely making any difference in substrate solubility in the absence of surfactant. The properly prolonged grinding time can make up for the loss in substrate solubility arising from the reduction in surfactant concentration. The surfactant complexes composed of surfactants PSE and MGE at appropriate ratios are screened out with orthodoxy experiment method. the interaction between PSE and MGE exerts the most prominent effects on substrate bioconversion, and the surfactant complexes show more beneficial effects on steroid bioconversion than the surfactant PSE used alone.

Role of Acetylated p53 in Regulating the Expression of map2 in Retinoic Acid-induced P19 Cells

Objective To investigate the regulatory mechanisms of acetylated p53 in the expression of microtubule-associated protein-2(MAP2) in neuronal differentiation of P19 cells induced by all-trans retinoic acid(RA).Methods Neuronal differentiation of P19 cells was initiated with 4-day RA treatment.Immunofluorescence,real-time reverse transcription-polymerase chain reaction(RT-PCR) assay,and map2 promoter driven luciferase assay were performed to detect the expression and relative promoter activity of MAP2 in those RA-treated cells.Real-time PCR-based chromatin immunoprecipitation assay(ChIP) was carried out to reveal the specific recruitment of acetylated p53 onto its binding sites on map2 promoter.Results The expression of MAP2 was markedly increased in RA-induced P19 cells.The map2 mRNA increased 34-fold after 4 days of RA treatment and 730-fold 2 days after the treatment,compared with the cells without RA treatment(control).p53 was recruited to the promoter of map2 gene in acetylated form and thereby enhanced its promoter activity.p300/CBP associated factor(PCAF) was found induced in RA-treated cells and enriched in the nucleus,which might contribute to the acetylation of p53 in the regulation of map2 gene.Conclusions Acetylated p53 may participate in regulating the expression of map2 in RA-induced differentiation of P19 cells.PCAF is possibly involved in this process by mediating the acetylation of p53.

Association Between IL-6 （Interleukin-6） and Iron Status in Rheumatoid Arthritis Patients

The study was performed to determine whether the srum concentrations of IL （interleukin）-6 are elevated in patients with RA （rheumatoid arthritis） and to investigate the relationship between IL-6 levels and iron status in RA patients. 95 serum samples were obtained, 70 of them from patients with RA who had visited the department of Rheumatology at Al-Sadder medical city in Najaf governorate （Iraq） and 25 age and sex-matched healthy controls. The authors assessed the clinical parameters of the disease, including ESR （erythrocyte sedimentation rate）, CRP （C-reactive protein）, and RF （rheumatoid factor）. Serum levels of iron and TIBC （total iron binding capacity） were measured spectrophotometrically, while TS% （transferrin saturation percentage） and transferrin concentration were calculated mathematically. Serum concentrations of IL-6 （interleukin-6） and ferritin were measured using an ELISA （enzyme-linked immunosorbent assay）. The results of serum concentration of IL-6 （interleukin-6） and ferritin were significantly elevated （P 〈 0.0001） in patients with RA compared to those of healthy controls. On the other hand, serum concentrations of iron, TIBC （total iron binding capacity）, TS% （transferrin saturation percentage） and transferrin concentration were significantly decreased in patients with RA compared with those of healthy controls. These findings suggest that anemia is the most frequent observations in patients with RA and mostly associative with increasing level of interleukin-6.

英语短语动词特性试析

短语动词(phrasal verbs),即以动词和副词或和介词组成的短语结构,在现代英语中占有十分重要的地位,它们有自己的不少独特之处,因而在此作为专题加以剖析。 我们探讨短语动词的出发点,是把它们作为英语习语的一个重要组成部分。因此。

Single nucleotide polymorphisms in the human corticosteroid-binding globulin promoter alter transcriptional activity

Corticosteroid-binding globulin(CBG) is a high-affinity plasma protein that transports glucocorticoids and progesterone.Others and we have reported non-synonymous single nucleotide polymorphisms(SNPs) that influence CBG production or steroid-binding activity.However,no promoter polymorphisms affecting the transcription of human CBG gene(Cbg) have been reported.In the present study we investigated function implications of six promoter SNPs,including 26 C/G,54 C/T,144 G/C,161 A/G,205 C/A,and 443/444 AG/,five of which are located within the first 205 base pairs of 5'-flanking region and close to the highly conserved footprinted elements,TATA-box,or CCAAT-box.Luciferase reporter assays demonstrated that basal activity of the promoter carrying 54 T or 161 G was significantly enhanced.The first three polymorphisms,26 C/G,54 C/T,and 144 G/C located close to the putative hepatic nuclear factor(HNF) 1 binding elements,altered the transactivation effect of HNF1.We also found a negative promoter response to dexamethasone-activated glucocorticoid receptor(GR),although none of the SNPs affected its transrepression function.Our results suggest that human Cbg 26 C/G,54 C/T,144 G/C,and 161 A/G promoter polymorphisms alter transcriptional activity,and further studies are awaited to explore their association with physiological and pathological conditions.

The effect of transposable elements on phenotypic variation： insights from plants to humans

Transposable elements(TEs), originally discovered in maize as controlling elements, are the main components of most eukaryotic genomes. TEs have been regarded as deleterious genomic parasites due to their ability to undergo massive amplification. However, TEs can regulate gene expression and alter phenotypes. Also, emerging findings demonstrate that TEs can establish and rewire gene regulatory networks by genetic and epigenetic mechanisms. In this review, we summarize the key roles of TEs in fine-tuning the regulation of gene expression leading to phenotypic plasticity in plants and humans, and the implications for adaption and natural selection.

Pyridin-2(1H)-ones as HIV-1 NNRTIs:a combinatorial optimization strategy

With rapid spread of HIV(human immunodeficiency virus) on a global scale and increasingly severe drug-resistance of it,it is urgently necessary to develop novel effective anti-HIV drugs.Non-nucleoside reverse transcriptase inhibitor(NNRTIs)is one of the most significant antiretroviral drugs for fighting against HIV infection due to their various structures,unique mode of action,good efficacy and low toxicity.Pyridinone derivatives,a type of NNRTIs,have been reported to achieve remarkable development in the past few decades.In this review,we summarized current drug design and medicinal chemistry efforts toward the development of next-generation pyridinones as HIV-1 NNRTIs.

Stable homotopy classification of A_n^4-polyhedra with 2-torsion free homology

We study the stable homotopy types of F_n^4(2)-polyhedra, i.e.,(n- 1)-connected, at most(n+ 4)-dimensional polyhedra with 2-torsion free homologies. We are able to classify the indecomposable F_n^4(2)-polyhedra. The proof relies on the matrix problem technique which was developed in the classification of representations of algebras and applied to homotopy theory by Baues and Drozd(1999, 2001, 2004).

Pairwise interactions in gene expression determine a hierarchical transcriptional profile in the human brain

The orchestrated expression of thousands of genes gives rise to the complexity of the human brain.However,the structures governing these myriad gene-gene interactions remain unclear.By analyzing transcription data from more than 2000 sites in six human brains,we found that pairwise interactions between genes,without considering any higher-order interactions,are sufficient to predict the transcriptional pattern of the genome for individual brain regions and the transcriptional profile of the entire brain consisting of more than 200 areas.These findings suggest a quadratic complexity of transcriptional patterns in the human brain,which is much simpler than expected.In addition,using a pairwise interaction model,we revealed that the strength of gene-gene interactions in the human brain gives rise to the nearly maximal number of transcriptional clusters,which may account for the functional and structural richness of the brain.