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1.
Proboscipedia (PB) is a HOX protein required for adult maxillary palp and proboscis formation. To identify domains of PB important for function, 21 pb point mutant alleles were sequenced. Twelve pb alleles had DNA sequence changes that encode an altered PB protein product. The DNA sequence changes of these 12 alleles fell into 2 categories: missense alleles that effect the PB homeodomain (HD), and nonsense or frameshift alleles that result in C-terminal truncations of the PB protein. The phenotypic analysis of the pb homeobox missense alleles suggests that the PB HD is required for maxillary palp and proboscis development and pb - Sex combs reduced (Scr) genetic interaction. The phenotypic analysis of the pb nonsense or frameshift alleles suggests that the C-terminus is an important region required for maxillary palp and proboscis development and pb-Scr genetic interaction. PB and SCR do not interact directly with one another in a co-immunoprecipitation assay and in a yeast two-hybrid analysis, which suggests the pb-Scr genetic interaction is not mediated by a direct interaction between PB and SCR.  相似文献   
2.
Based on a detailed study of the solubility of serum albumin, a procedure for its purification by selective ammonium sulphate precipitation has been developed. Using buffalo serum, first extraneous proteins were precipitated by making the serum 2.26 M saturated with ammonium sulphate at pH 7.0 and then albumin was precipitated from the supernatant at 1.9 M ammonium sulphate concentration at pH 4.2. The overall yield of serum albumin thus isolated was about 55% with a purity of 97%. The protein preparation gave a single nearly symmetrical peak on Sephadex G-100 column and virtually a single band on polyacrylamide gel electrophoresis in the presence and absence of SDS. Buffalo serum albumin has a molecular weight of 69,000 Da. The hydrodynamic properties such as Stoke's radius (3.70 nm), diffusion coefficient (6.03 X 10(-7) cm2/s) and frictional ratio (1.36) obtained by analytical gel chromatography, bilirubin binding characteristics and its interaction with anti-bovine serum albumin antiserum suggest that buffalo serum albumin is very similar to BSA in its molecular properties.  相似文献   
3.

Cotton fibre quality is a multigenic trait. Genetic modification of different genes to achieve high quality fibre is difficult without knowing the mechanism lying behind genes interaction. Based on background knowledge an attempt to explore the potential structural interactions between Gossypium hirsutum Wlim5 domain1 and Gossypium hirsutum ACTIN-1 proteins was done in current study. Sequence features of the LIM domain1 of GhWlim5 protein were identified through multiple sequence alignment analysis, and a phylogenetic tree was built to identify evolutionary relationships between sequences. Conservation indicated the evolutionary importance of side chain residues and the presence of several aliphatic and/or bulky residues, which stabilize the protein core and facilitate packing of zinc fingers. The structures of GhWlim5 domain1 and GhACTIN-1 proteins were modelled and validated through computational methods. Validation of GhACTIN-1 and GhWlim5 domain1 structures indicated good structural quality with 99.7% and 100% of the favoured number of residues in allowed regions and Z-score, within the ranges of − 9.87 and − 4.17, respectively. Docking analysis indicated various possible modes of interaction between these two proteins with favourable binding affinities. Based on our strong binding interaction results between GhWlim5 domain1 and GhACTIN-1 proteins, we further investigated the role of over-expression of GhWlim5 by transformation in cotton plants under fibre specific promoter and transgenic plants displayed significant increases in fibre strength.

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4.
Animal models have contributed greatly to our understanding of human diseases. Here, we focus on cornea epithelial stem cell (CESC) deficiency (commonly called limbal stem cell deficiency, LSCD). Corneal development, homeostasis and wound healing are supported by specific stem cells, that include the CESCs. Damage to or loss of these cells results in blindness and other debilitating ocular conditions. Here we describe the contributions from several vertebrate models toward understanding CESCs and LSCD treatments. These include both mammalian models, as well as two aquatic models, Zebrafish and the amphibian, Xenopus. Pioneering developments have been made using stem cell transplants to restore normal vision in patients with LSCD, but questions still remain about the basic biology of CESCs, including their precise cell lineages and behavior in the cornea. We describe various cell lineage tracing studies to follow their patterns of division, and the fates of their progeny during development, homeostasis, and wound healing. In addition, we present some preliminary results using the Xenopus model system. Ultimately, a more thorough understanding of these cornea cells will advance our knowledge of stem cell biology and lead to better cornea disease therapeutics.  相似文献   
5.
Abstract

Acinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000?µg ml?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120?µg ml?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production.  相似文献   
6.
A new isolate of Trichoderma atroviride has been shown to grow on low rank coal as the sole carbon source. T. atroviride ES11 degrades approximately 82% of particulate coal (10 g l(-1)) over a period of 21 days with 50% reduction in 6 days. Glucose (5 g l(-1)) as a supplemented carbon source enhanced the coal solubilisation efficiency of T. atroviride ES11, while 10 and 20 g l(-1) glucose decrease coal solubilisation efficiency. Addition of nitrogen [1 g l(-1) (NH(4))(2)SO(4)] to the medium also increased the coal solubilisation efficiency of T. atroviride ES11. Assay results from coal-free and coal-supplemented cultures suggested that several intracellular enzymes are possibly involved in coal depolymerisation processes some of which are constitutive (phenol hydroxylase) and others that were activated or induced in the presence of coal (2,3-dihydrobiphenyl-2,3-diol dehydrogenase, 3,4-dihydro phenanthrene-3,4-diol dehydrogenase, 1,2-dihydro-1,2-dihydroxynaphthalene dehydrogenase, 1,2-dihydro-1,2-dihydroxyanthracene dehydrogenase). GC-MS analysis of chloroform extracts obtained from coal degrading T. atroviride ES11 cultures showed the formation of only a limited number of specific compounds (4-hydroxyphenylethanol, 1,2-benzenediol, 2-octenoic acid), strongly suggesting that the intimate association between coal particles and fungal mycelia results in rapid and near-quantitative transfer of coal depolymerisation products into the cell.  相似文献   
7.
Many individuals cannot obtain the optimum calcium requirement from food for a variety of reasons. Therefore, calcium supplements are important sources of dietary calcium. One of the calcium sources commercially available is LactoCalcium (milk minerals) that has 28% calcium, and a 2:1 ratio of calcium to phosphorus. The objectives of this study were (a) to examine whether calcium can be released from LactoCalcium by using digestive enzymes and (b) to determine its biological activity by examining its ability to stimulate bone formation. LactoCalcium was treated in vitro by using simulated gastric and intestinal fluids or porcine gastric, pancreatic and intestinal extracts. Our results indicate the role of enzymes or bile extract in the digestion of the product. We show that, by increasing the concentration of pepsin at a fixed concentration of LactoCalcium (substrate), the percentage of released calcium increased in a dose-dependent manner, showing that, at the right enzyme concentration, as much as 100% of the calcium present in LactoCalcium can be made available. The biological activity of the digested calcium was demonstrated by the stimulation of mineralized bone nodules in SaOS-2 cells in a dose-dependent manner. Thus, 1 mM and 3 mM calcium released from LactoCalcium increased the nodule area by 23.17 mm(2) (p<0.0001) and 77.78 mm(2) (p<0.0001), respectively, as compared to a value of 0.99 mm(2) at 0.5 mM calcium from LactoCalcium. These results demonstrate the in vitro bioavailability and bioactivity of calcium from LactoCalcium and serve as a basis for carrying out in vivo analyses to determine the suitability of using LactoCalcium as a source of calcium for individuals at risk of developing osteoporosis.  相似文献   
8.
In the present study, we have demonstrated the suitability of microspheres in removal of plasma bilirubin from systemic circulation of hyperbilirubinemic rats. Poly (lactide co-glycolide) microspheres (PLGA microspheres) have been shown to bind with bilirubin in both a concentration and time dependent manner. The binding affinity of bilirubin to microspheres was enhanced when rat serum albumin (RSA) was loaded into the microspheres. On evaluating the potential of microspheres in elimination of bilirubin from the systemic circulation, RSA bearing microspheres were found to be competent in both removing bilirubin from the systemic circulation and controlling elevated plasma levels of liver function enzymes in temporarily hyperbilirubinemic rats. On the basis of results of the present study, we suggest that microsphere-based delivery system may help in development of safe, effective and alternate strategy for the treatment of hyperbilirubinemic conditions in model animals.  相似文献   
9.
Mycoplasma mastitis is often difficult to control due to a lack of rapid and accurate diagnostic tools. The aim of the current study was to develop a loop-mediated isothermal amplification (LAMP) assay for the detection of Mycoplasma bovis (M. bovis) in mastitic milk. The assay was developed using primers designed for three different target genes: uvrC, 16S rRNA, and gyrB, and validated using mastitic milk samples previously found positive for the target pathogen. Specificity of the developed assay was determined by testing cross-reactivity of LAMP primers against closely related bovine mastitis bacterial pathogens. The sensitivity was found to be higher compared to conventional polymerase chain reaction (PCR). The LAMP assay was also capable of detecting M. bovis in PCR-negative milk samples of cows with clinical mastitis. The uvrC primers were found to be more sensitive, while gyrB primers were more specific; however, 16S rRNA primers were less specific and sensitive compared to either uvrC or gyrB primers. Cohen’s kappa values for uvrC, gyrB, and 16S rRNA primers used in the LAMP assays were 0.940, 0.970, and 0.807, respectively. There was a high level of agreement between the test results and the true-disease status as indicated by the receiver operating characteristic (ROC) curve. Our findings suggest that the newly developed LAMP assays targeting the uvrC and gyrB genes could be a useful tool for rapid and accurate diagnosis of mastitis caused by M. bovis.  相似文献   
10.
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels.  相似文献   
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