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71.
Linear electron beam radiation was used to induce grafting of glycidyl methacrylate/β-cyclodextrin mixture onto cotton fabric. Chlorohexidin diacetate was incorporated to the cavities of cyclodextrin fixed on the cotton fabric to form an inclusion complex having antimicrobial activity. After incorporating chlorohexidin diacetate, the fabric was subjected to several washing cycles to examine the durability of the antimicrobial finishing. Control and grafted cotton fabrics (before and after loading with antimicrobial agent) were characterized for their antimicrobial activity against different kinds of bacteria and fungi.Grafted fabrics loaded with antimicrobial agent were found to show good antimicrobial activity in comparison with control and grafted fabrics which are not loaded with antimicrobial agent. The grafted fabrics loaded with antimicrobial agent were found also to exhibit good antimicrobial activity after five washings and this lasting antimicrobial activity can be attributed to the inclusion complex formed between chlorohexidin diacetate molecules and the cavities of cyclodextrin.  相似文献   
72.
In this paper, a new approach based on eigen-systems pseudo-spectral estimation methods, namely Eigenvector (EV) and MUSIC, and Multiple Layer Perceptron (MLP) neural network is introduced. In this approach, the calculated EEG (electroencephalogram) spectrum is divided into smaller frequency sub-bands. Then, a set of features, {maximum, entropy, average, standard deviation, mobility}, are extracted from these sub-bands. Next, incorporating a set of the EEG time domain features {standard deviation, complexity measure} with the spectral feature set, a feature vector is formed. The feature vector is then fetched into a MLP neural network to classify the signal into the following three states: normal (healthy), epileptic patient signal in a seizure-free interval (inter-ictal), and epileptic patient signal in a full seizure interval (ictal). The experimental results show that the classification of the EEG signals maybe achieved with approximately 97.5% accuracy and the variance of 0.095% using an available public EEG signals database. The results are among the best reported methods for classifying the three states aforementioned. This is a high speed with high accuracy as well as low misclassifying rate method so it can make the practical and real-time detection of this chronic disease feasible.  相似文献   
73.
Immobilization of uranium in groundwater can be achieved through microbial reduction of U(VI) to U(IV) upon electron donor addition. Microbial community structure was analyzed in ethanol-biostimulated and control sediments from a high-nitrate (>130 mM), low-pH, uranium-contaminated site in Oak Ridge, TN. Analysis of small subunit (SSU) rRNA gene clone libraries and polar lipid fatty acids from sediments revealed that biostimulation resulted in a general decrease in bacterial diversity. Specifically, biostimulation resulted in an increase in the proportion of Betaproteobacteria (10% of total clones in the control sediment versus 50 and 79% in biostimulated sediments) and a decrease in the proportion of Gammaproteobacteria and Acidobacteria. Clone libraries derived from dissimilatory nitrite reductase genes (nirK and nirS) were also dominated by clones related to Betaproteobacteria (98% and 85% of total nirK and nirS clones, respectively). Within the nirK libraries, one clone sequence made up 59 and 76% of sequences from biostimulated sediments but only made up 10% of the control nirK library. Phylogenetic analysis of SSU rRNA and nirK gene sequences from denitrifying pure cultures isolated from the site indicate that all belong to a Castellaniella species; nearly identical sequences also constituted the majority of biostimulated SSU rRNA and nirK clone libraries. Thus, by combining culture-independent with culture-dependent techniques, we were able to link SSU rRNA clone library information with nirK sequence data and conclude that a potentially novel Castellaniella species is important for in situ nitrate removal at this site.  相似文献   
74.
Isolates of Cryptosporidium spp. from human and animal hosts in Iran were characterized on the basis of both the 18S rRNA gene and the Laxer locus. Three Cryptosporidium species, C. hominis, C. parvum, and C. meleagridis, were recognized, and zoonotically transmitted C. parvum was the predominant species found in humans.  相似文献   
75.
We investigated the phylogenetic diversity and metabolic capabilities of members of the phylum Planctomycetes in the anaerobic, sulfide-saturated sediments of a mesophilic spring (Zodletone Spring) in southwestern Oklahoma. Culture-independent analyses of 16S rRNA gene sequences generated using Planctomycetes-biased primer pairs suggested that an extremely diverse community of Planctomycetes is present at the spring. Although sequences that are phylogenetically affiliated with cultured heterotrophic Planctomycetes were identified, the majority of the sequences belonged to several globally distributed, as-yet-uncultured Planctomycetes lineages. Using complex organic media (aqueous extracts of the spring sediments and rumen fluid), we isolated two novel strains that belonged to the Pirellula-Rhodopirellula-Blastopirellula clade within the Planctomycetes. The two strains had identical 16S rRNA gene sequences, and their closest relatives were isolates from Kiel Fjord (Germany), Keauhou Beach (HI), a marine aquarium, and tissues of marine organisms (Aplysina sp. sponges and postlarvae of the giant tiger prawn Penaeus monodon). The closest recognized cultured relative of strain Zi62 was Blastopirellula marina (93.9% sequence similarity). Detailed characterization of strain Zi62 revealed its ability to reduce elemental sulfur to sulfide under anaerobic conditions, as well as its ability to produce acids from sugars; both characteristics may potentially allow strain Zi62 to survive and grow in the anaerobic, sulfide- and sulfur-rich environment at the spring source. Overall, this work indicates that anaerobic metabolic abilities are widely distributed among all major Planctomycetes lineages and suggests carbohydrate fermentation and sulfur reduction as possible mechanisms employed by heterotrophic Planctomycetes for growth and survival under anaerobic conditions.  相似文献   
76.
As with chromosomal DNA, the mitochondrial DNA (mtDNA) can contain mutations that are highly pathogenic .In fact, many diseases of the central nervous system are known to be caused by mutations in mtDNA. Dysfunction of the mitochondrial Respiratory Chain (RC) has been shown in patients with neurological disease including Alzheimer’s disease (AD), Parkinson’s disease (PD) and Multiple sclerosis (MS). MS is a demyelinating disease of central nervous system characterized by morphological hallmarks of inflammation, demyelination and axonal loss. Considering this importance, we decided to investigate several highly mutative parts of mtDNA for point mutations as MT-LTI (tRNALeucine1(UUA/G)), MT-NDI (NADH Dehydrogenase subunit 1), MT-COII (Cytochrome c oxidase subunit II), MT-TK (tRNALysine), MT-ATP8 (ATP synthase subunit F0 8) and MT-ATP6 (ATP synthase subunit F0 6) in 20 Iranian MS patients and 80 age-matched control subjects by PCR and automated DNA sequencing to evaluate any probable point mutations. Our results revealed that 15 (75%) out of 20 MS patients had point mutations. Some of point mutations were newly found in this study. This study suggested that point mutation occurred in mtDNA might be involved in pathogenesis of MS.  相似文献   
77.
The D-3-hydroxybutyrate dehydrogenase (BDH) (EC 1.1.1.30) from liver jerboa (Jaculus orientalis), a ketone body converting enzyme in mitochondria, in two populations of mitochondria (heavy and light) has been studied in different jerboa states (euthermic, prehibernating and hibernating). The results reveal: (1) important variations between states in terms of ketones bodies, glucose and lipid levels; (2) significant differences between the BDH of the two mitochondrial populations in term of protein expression and kinetic properties. These results suggest that BDH leads an important conformational change depending on the physiological state of jerboa. This BDH structural change could be the consequence of the lipid composition modifications in inner mitochondrial membrane leading to changes in BDH catalytic properties.  相似文献   
78.
In Diabetes Mellitus (DM), glucose and the aldehydes glyoxal and methylglyoxal modify free amino groups of lysine and arginine of proteins forming advanced glycation end products (AGEs). Elevated levels of these AGEs are implicated in diabetic complications including nephropathy. Our objective was to measure carboxymethyl cysteine (CMC) and carboxyethyl cysteine (CEC), AGEs formed by modification of free cysteine sulfhydryl groups of proteins by these aldehydes, in plasma proteins of patients with diabetes, and investigate their association with the albumin creatinine ratio (ACR, urine albumin (mg)/creatinine (mmol)), an indicator of nephropathy. Blood was collected from forty-two patients with type 1 and 2 diabetes (18–36 years) and eighteen individuals without diabetes (17–35 years). A liquid chromatography-mass spectrophotometric method was developed to measure plasma protein CMC and CEC levels. Values for ACR and hemoglobin A1C (HbA1C) were obtained. Mean plasma CMC (μg/l) and CEC (μg/l) were significantly higher in DM (55.73 ± 29.43, 521.47 ± 239.13, respectively) compared to controls (24.25 ± 10.26, 262.85 ± 132.02, respectively). In patients with diabetes CMC and CEC were positively correlated with ACR, as was HbA1C. Further, CMC or CEC in combination with HbA1C were better predictors of nephropathy than any one of these variables alone. These results suggest that glucose, glyoxal, and methylglyoxal may all be involved in the etiology of diabetic nephropathy.  相似文献   
79.
The formation of biofilm is a universal bacterial survival strategy. Biofilms occur on inert and living support in the natural environment and in industrial installations. This microenvironment leads to the horizontal transfer of genetic material between bacteria by physical contact. In order to evaluate the relationship between biofilm-forming capabilities, surface characteristics and plasmid content we purified from Salmonella a plasmid conferring resistance to cephalosporin and transferred it by electroporation to E.coli DH10B originally unable to form biofilm in inert surface. We demonstrated the association between a plasmid conferring resistance to expanded-spectrum cephalosporin and biofilm formation. We also noted that this plasmid influences the cell surface properties and cell motility.  相似文献   
80.
UV-B effect on constituents of Azolla caroliniana   总被引:1,自引:0,他引:1  
Changes in growth and ultrastructure of Azolla caroliniana in response to elevated UV-B radiation were investigated. Exposure of plants to UV-B radiation for 1, 8, 16, 24 and 48 h exhibited a significant decrease in biomass and relative growth rate. This decrease resulted in an increase in doubling time over the control. Also, Chl a and b contents were significantly decreased especially after 16 h. The reduction was accompanied by a decrease in 5-aminolaevulinic acid content (precursor of chlorophyll). On the other hand, contents of carotenoid and UV-absorbing phenolic compounds (flavonoids and anthocyanins) were increased.  相似文献   
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