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61.
62.
Circular RNAs (circRNAs) are a new class of non-coding RNAs in animals and are a novel target of non-coding RNA (ncRNA) regulation. The mechanism and function of circRNAs have been reported in some species and tissues. However, there is little available information on the functions of circRNAs in the goat reproductive system. In the present study, we deeply sequenced and analyzed circRNAs through bioinformatics to reveal the expression profiles, and predicted 13,950 circRNAs in the pre-ovulatory ovarian follicles of goats for the first time. Thirty-seven circRNAs were differentially expressed in the Boer goat compared with the Macheng black goat. The chi_circ_0008219 was involved in a vast circRNA-miRNA-mRNA co-expression network. Via a luciferase activity assay, chi_circ_0008219 is observed to sponge to 3 ovarian follicle-related miRNAs. These findings demonstrate that circRNAs have potential effects in the ovarian follicles of ewes and may represent a promising new research field in ovarian follicular development.  相似文献   
63.
Bacillus subtilis, belonging to the type species of Bacillus, is a type of soil-derived, low %G+C, endospore-forming Gram-positive bacterium. After the discovery of B. subtilis 168 that displayed natural competence, this bacterium has been intensively considered to be an ideal model organism and a robust host to study several basic mechanisms, such as metabolism, gene regulation, bacterial differentiation, and application for industrial purposes, such as heterologous protein expression and the overproduction of an array of bioactive molecules. Since the first report of heterologous overproduction of recombinant proteins in this strain, the bulk production of a multitude of valuable enzymes, especially industrial enzymes, has been performed on a relatively large scale. Since B. subtilis can non-specifically secrete recombinant proteins using various signal peptides, it has tremendous advantages over Gram-negative bacterial hosts. Along with the report of the complete genome sequence of B. subtilis, a number of genetic tools, including diverse types of plasmids, bacterial promoters, regulatory elements, and signal peptides, have been developed and characterized. These novel genetic elements tremendously accelerated genetic engineering in B. subtilis recombinant systems. In addition, with the development of several complex gene expression systems, B. subtilis has performed a number of more complex functions. This ability enables it to be a substantial chassis in synthetic biology rather than just a workhorse for the overproduction of recombinant proteins. In this review, we review the progress in the development of B. subtilis as a universal platform to overproduce heterologous diverse high-value enzymes. This progress has occurred from the development of biological parts, including the characterization and utilization of native promoters, the fabrication of synthetic promoters and regulatory elements, and the assembly and optimization of genetic systems. Some important industrial enzymes that have been produced in large quantities in this host are also summarized in this review. Furthermore, the ability of B. subtilis to serve as a cellular tool was also briefly recapitulated and reviewed.  相似文献   
64.
A new “turn-on” fluorescent probe, RDMBM, based on the rhodamine B dye and the 2,5-pyrrolidinedione moiety was synthesized and characterized. Its sensing behavior toward various amino acids was evaluated via UV–vis and fluorescence spectroscopic techniques. The observed spectral changes showed that RDMBM displays high selectivity and sensitivity toward GSH in MeOH/H2O (1:2, v/v, pH 7.40, Tris-HCl buffer, 1?mM) solution and that it undergoes 1:1 covalent binding with GSH. More importantly, the hydrogenation and ring-opening of the nitrogen atom in the spirane structure of rhodamine B derivatives were tightly bound to the induction effects of different groups. Furthermore, fluorescence imaging applications demonstrated that RDMBM can be successfully used for the detection of GSH in human breast cancer cells MCF-7.  相似文献   
65.
1 前言 农作物中铅的含量在很大程度上反映出土壤和成土母岩中铅的水平。铅是一种有毒元素,人体摄入过量的铅,就会导致一系列的病变。因此,农作物中铅的测定对调查和评价环境中铅的污染,估算人畜食入铅的量,研究各类因铅中毒引起的疾病,做到对症下药具有十分重要的意义。本文根据前人的经验研  相似文献   
66.
Xyloglucan endotransglycosylase/hydrolase (XTH) enzymes have played a role in the remodeling of cell wall hemicelluloses. To investigate the function of XTHs in persimmon (Diospyros kaki L.) fruit development and postharvest softening, five cDNAs (DkXTH1 to DkXTH5), whose putative proteins contained the conserved DEIDFEFLG motif of XTH, were cloned. Real time quantitative PCR analysis revealed that DkXTH1, DkXTH4, and DkXTH5 peaked in immature expanding fruit, and their higher expression was observed along with higher fruit firmness in cold-treated fruit or firmer cultivar fruit during storage. The opposite gene expression patterns were observed in DkXTH2 and DkXTH3, which reached maxima concomitance with pronounced fruit softening. Meanwhile, the xyloglucan endotransglycosylase (XET) enzymes play important roles in both the rapid growth and ripening of persimmon fruit. Furthermore, the recombined DkXTH1 and DkXTH2 proteins showed significant XET activity without any detected XEH activity. However, the XET activity of recombined DkXTH2 protein had a higher affinity for small acceptor molecules than that of recombined DkXTH1 protein. The former might prefer to participate in cell wall restructuring, and the latter is more inclined to participate in cell wall assembly. Besides, DKXTH proteins could function by targeting to the cell wall under regulation of a signal peptide. The data suggested that individual DKXTHs could exhibit different patterns of expression, and the encoded products possessed specific enzymatic properties conferring on their respective functions in growth and postharvest softening of persimmon fruit.  相似文献   
67.
Suo  Ning  Wu  Yidi  Zhou  Zhixiong  He  Qian  Bai  Huaqiang  Lin  Huanling  Ke  Qiaozhen  Xu  Peng 《Marine biotechnology (New York, N.Y.)》2022,24(5):927-941
Marine Biotechnology - Large yellow croaker (Larimichthys crocea) is one of the most economically important fish in China. Recently, global climate change has caused more and more intense and...  相似文献   
68.
目的探讨非小细胞肺癌(non-small cell lung cancer,NSCLC)患者中表皮生长因子受体(epidermic growth factor receptor,EGFR)突变、间变性淋巴瘤激酶(anaplastic lymphoma kinase,ALK)和ROS1融合基因的表达情况及其与临床病理特征的关系。方法应用ARMS法检测379例非小细胞肺癌患者中EGFR突变、ALK和ROS1融合基因的表达情况,并分析其与患者临床病理特征的关系。结果 379例非小细胞肺癌患者组织中,EGFR突变率为36.15%(137/379),19del和L858R突变为其主要突变类型,同时检出L858R和T790双突变4例,L858R和19del双突变2例;EGFR突变人群主要是女性、腺癌、非吸烟患者(P<0.05)。ALK融合基因阳性率为3.43%(13/379),其中ALK-M1融合基因型4例,ALK-M2融合基因型3例,ALK-M3融合基因型3例,ALK-M4融合基因型1例,ALK-M6融合基因型2例。ROS1融合基因阳性率为3.17%(12/379),主要为ROS1-M8融合基因型(8例),存在1例ROS1-M3和ROS1-M8融合基因型双融合。不同性别、年龄、组织学和吸烟状况的NSCLC患者ALK和ROS1基因突变率无统计学差异。结论 EGFR基因在NSCLC患者中存在较高的突变率,而ALK、ROS1融合基因在NSCLC患者中突变率较低,但代表了非小细胞肺癌的特点分子亚型,为指导临床靶向治疗提供依据。  相似文献   
69.
We investigated whether cosupplementation with synthetic tetra-tert-butyl bisphenol (BP) and vitamin C (Vit C) ameliorated oxidative stress and acute kidney injury (AKI) in an animal model of acute rhabdomyolysis (RM). Rats were divided into groups: Sham and Control (normal chow), and BP (receiving 0.12% w/w BP in the diet; 4 weeks) with or without Vit C (100mg/kg ascorbate in PBS ip at 72, 48, and 24h before RM induction). All animals (except the Sham) were treated with 50% v/v glycerol/PBS (6 mL/kg injected into the hind leg) to induce RM. After 24h, urine, plasma, kidneys, and aortae were harvested. Lipid oxidation (assessed as cholesteryl ester hydroperoxides and hydroxides and F(2)-isoprostanes accumulation) increased in the kidney and plasma and this was coupled with decreased aortic levels of cyclic guanylylmonophosphate (cGMP). In renal tissues, RM stimulated glutathione peroxidase (GPx)-4, superoxide dismutase (SOD)-1/2 and nuclear factor kappa-beta (NFκβ) gene expression and promoted AKI as judged by formation of tubular casts, damaged epithelia, and increased urinary levels of total protein, kidney-injury molecule-1 (KIM-1), and clusterin. Supplementation with BP±Vit C inhibited the two indices of lipid oxidation, down-regulated GPx-4, SOD1/2, and NF-κβ gene responses and restored aortic cGMP, yet renal dysfunction and altered kidney morphology persisted. By contrast, supplementation with Vit C alone inhibited oxidative stress and diminished cast formation and proteinuria, while other plasma and urinary markers of AKI remained elevated. These data indicate that lipid- and water-soluble antioxidants may differ in terms of their therapeutic impact on RM-induced renal dysfunction.  相似文献   
70.

Key message

Highly variable regions of chloroplast genome were found to be useful in the detection of plant genetic diversity at micro-evolution level. Our methodology will improve understanding and conservation of plant diversity.

Abstract

Tree peonies are famous flowers with about 2,000 cultivars in the world, belonging to Paeonia sect. Moutan of the Paeoniaceae. They are traditionally classified based on flower forms and colors. Due to the limited number of DNA and morphological markers, and the existence of synonyms and homonyms, evaluation on genetic diversity of so many cultivars remains a challenge. In most cases, it is difficult and even impossible to discriminate tree peony cultivars when they are not in flower. In this study, single nucleotide polymorphism detected from the hyper-variable regions of chloroplast genome was employed to separate tree peony cultivars into different maternal lineages which can be expressed briefly by a nucleotide molecular formula. Our approach enabled a much higher resolution of cultivar identification and classification that has not been obtained before. The newly developed hyper-variable chloroplast markers, as an independent source of taxonomic characteristics, provided novel evidences and higher resolution ability that are helpful in building an effective classification system for evaluation, conservation, and utilization of the tree peony germplasm resources at cultivar level.  相似文献   
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