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31.
Md Robiul Karim Sumei Zhang Fuchun Jian Jiacheng Li Chunxiang Zhou Longxian Zhang Mingfei Sun Guangyou Yang Fengcai Zou Haiju Dong Jian Li Farzana Islam Rume Meng Qi Rongjun Wang Changshen Ning Lihua Xiao 《International journal for parasitology》2014
Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70 kDa heat shock protein (hsp70) and 60 kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois’ leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis. 相似文献
32.
Sara L. Payne Sonsoles Rodriguez-Aristegui Julia Bardos Céline Cano Bernard T. Golding Ian R. Hardcastle Marcus Peacock Nahida Parveen Roger J. Griffin 《Bioorganic & medicinal chemistry letters》2010,20(12):3649-3653
Replacement of the core heterocycle of a defined series of chromen-4-one DNA-PK inhibitors by the isomeric chromen-2-one (coumarin) and isochromen-1-one (isocoumarin) scaffolds was investigated. Structure–activity relationships for DNA-PK inhibition were broadly consistent, albeit with a reduction of potency compared with the parent chromenone. 相似文献
33.
Influenza A virus (H1N1), a genetic reassortment of endemic strains of human, avian and swine flu, has crossed species barrier to human and apparently acquired the capability of human to human transmission. Some strains of H5N1 subtype are highly virulent because NS1 protein inhibits antiviral interferon α/β production. Another protein NS2 mediates export of viral ribonucleoprotein from nucleus to the cytoplasm through export signal. In this paper, we have studied structure-function relationships of these proteins of H1N1 subtype and have determined the cause of their pathogenicity. Our results showed that non-conservative mutations slightly stabilized or destabi- lized structural domains of NS1 or NS1-dsRNA complex, hence slightly increased or decreased the function of NS1 protein and consequently enhanced or reduced the pathogenicity of the H1N1 virus. NS2 protein of different strains carried non-conservative mutations in different domains, resulting in slight loss of function. These mutations slightly decreased the pathogenicity of the virus. Thus, the results confirm the structure-function relationships of these viral proteins. 相似文献
34.
A biosensor based on cytochrome c3 (cyt c3) has been introduced to detect and quantify superoxide radical (O2*-). Cyt c3, isolated from the sulfate-reducing bacterium (Desulfovibrio vulgaris Miyazaki F. strain), and its mutant were immobilized onto a conducting polymer coated electrodes by the covalent bonding with carbodiimide chemistry. The immobilization of cyt c3 was investigated with quartz crystal microbalance, electrochemical impedance spectroscopy, and cyclic voltammetric studies. The CVs recorded for cyt c3 and a mutant modified-electrodes showed a quasi-reversible behavior having the formal potential of about -471 and -476 mV (versus Ag/AgCl), respectively, in a 0.1M phosphate buffer solution (pH 7.0). The modified electrodes showed the surface controlled process and the electron transfer rate constants (ks) were evaluated to be 0.47 and 0.51 s(-1) for cyt c3 and mutant modified electrodes, respectively. A potential application of the cyt c3 modified electrode was evaluated by monitoring the bioelectrocatalytic response towards the O2*-. The hydrodynamic range of 0.2-2.7 micromole L(-1) and the detection limit of 0.05 micromole L(-1) were obtained. 相似文献
35.
Nishat Parveen Roberto Berni Sreeja Sudhakaran Javaid A. Bhat Suhas Shinde Naleeni Ramawat Vijay P. Singh Shivendra Sahi Rupesh Deshmukh Devendra K. Chauhan Durgesh Kumar Tripathi 《The Annals of applied biology》2022,180(1):7-25
Metalloids represent a wide range of elements with intermediate physiochemical properties between metals and non-metals. Many of the metalloids, like boron, selenium, and silicon are known to be essential or quasi-essential for plant growth. In contrast, metalloids viz. arsenic and germanium are toxic to plant growth. The toxicity of metalloids largely depends on their concentration within the living cells. Some elements, at low concentration, may be beneficial for plant growth and development; however, when present at high concentration, they often exert negative effects. In this regard, understanding the molecular mechanisms involved in the uptake of metalloids by roots, their subsequent transport to different tissues and inter/intra-cellular redistribution has great importance. The mechanisms of metalloids' uptake have been well studied in plants. Also, various transporters, as well as membrane channels involved in these processes, have been identified. In this review, we have discussed in detail the aspects concerning the positive/negative effects of different metalloids on plants. We have also provided a thorough account of the uptake, transport, and accumulation, along with the molecular mechanisms underlying the response of plants to these metalloids. Additionally, we have brought up the previous theories and debates about the role and effects of metalloids in plants with insightful discussions based on the current knowledge. 相似文献
36.
Vaish Swati Parveen Reshma Rajneesh Singh Nootan Gupta Divya Basantani Mahesh Kumar 《Journal of plant research》2022,135(6):823-852
Journal of Plant Research - Plant glutathione S-transferases are an ancient protein superfamily having antioxidant activity. These proteins are primarily involved in diverse plant functions such as... 相似文献
37.
38.
Masoud Zamani Esteki Eftychia Dimitriadou Ligia Mateiu Cindy Melotte Niels Van der Aa Parveen Kumar Rakhi Das Koen Theunis Jiqiu Cheng Eric Legius Yves Moreau Sophie Debrock Thomas D’Hooghe Pieter Verdyck Martine De Rycke Karen Sermon Joris R. Vermeesch Thierry Voet 《American journal of human genetics》2015,96(6):894-912
Methods for haplotyping and DNA copy-number typing of single cells are paramount for studying genomic heterogeneity and enabling genetic diagnosis. Before analyzing the DNA of a single cell by microarray or next-generation sequencing, a whole-genome amplification (WGA) process is required, but it substantially distorts the frequency and composition of the cell’s alleles. As a consequence, haplotyping methods suffer from error-prone discrete SNP genotypes (AA, AB, BB) and DNA copy-number profiling remains difficult because true DNA copy-number aberrations have to be discriminated from WGA artifacts. Here, we developed a single-cell genome analysis method that reconstructs genome-wide haplotype architectures as well as the copy-number and segregational origin of those haplotypes by employing phased parental genotypes and deciphering WGA-distorted SNP B-allele fractions via a process we coin haplarithmisis. We demonstrate that the method can be applied as a generic method for preimplantation genetic diagnosis on single cells biopsied from human embryos, enabling diagnosis of disease alleles genome wide as well as numerical and structural chromosomal anomalies. Moreover, meiotic segregation errors can be distinguished from mitotic ones. 相似文献
39.
Context
Recurrent miscarriage (RM), defined as three or more consecutive losses before the 20th week of gestation, affects 0.5–2% of pregnant women. In over 80% of cases, RM remains unexplained after investigations, suggesting the involvement of genetic factors.Objectives
The present study investigates the common polymorphisms of chemokine receptors CCR5 (NG_012637.1:g.5303A>G) and CX3CR1 (NG_016362.1:g.21065C>T, Thr280Met and NG_016362.1:g.20971G>A, Val249Ile) and their association with recurrent miscarriages (RM) among north Indian women.Participants and Methods
In a retrospective case-control study 200 well characterized patients with unexplained RM and 300 controls were genotyped for three polymorphic markers of CCR5 and CX3CR1 by restriction digestion of PCR amplified fragments.Results
Alleles and genotypes of CX3CR1 Val249Ile revealed statistically significant associations with RM cases when compared with the controls. The homozygous variant genotype Ile/Ile was found to be significantly higher among patients (p = 0.0002) when compared with the homozygous wild type Val/Val genotype. The haplotype of CX3CR1 that carried major alleles of Thr280Met and Val249Ile (T-V) showed statistically significant protective association (p < 0.0001, OR = 0.41, 95% CI = 0.31–0.54). The haplotype A-T-V (all wild type alleles) revealed a statistically significant protective association (p < 0.0001, OR = 0.41, 95% CI = 0.34–0.62), whereas the haplotypes G-T-I, A-T-I and A-M-V modified the risk of RM 1.9-fold, 5.5-fold and 5.1-fold respectively.Conclusions
A common polymorphism of CX3CR1 gene, Val240Ile is associated with the risk of RM in north Indian women. Risk of RM may also be modified by the presence of haplotypes T-I, M-V, G-T-I, A-T-I and A-M-V. 相似文献40.
Sollom R Richards AK Parmar P Mullany LC Lian SB Iacopino V Beyrer C 《PLoS medicine》2011,8(2):e1001007