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Poly(2-hydroxyethylmethacrylate–ethyleneglycoldimethacrylate) [poly(HEMA–EGDMA)] microspheres carrying Cibacron Blue F3GA and/or thionein were prepared and used for the removal of cadmium ions Cd(II) from human plasma. The poly(HEMA–EGDMA) microspheres, in the size range of 150–200 μm in diameter, were produced by a modified suspension copolymerization of HEMA and EGDMA. The reactive triazinyl dye-ligand Cibacron Blue F3GA was then covalently incorporated into the microspheres. The maximum dye incorporation was 16.5 μmol/g. Then, thionein was bound onto the Cibacron Blue F3GA-incorporated microspheres under different conditions. The maximum amount of thionein bound was 14.3 mg/g. The maximum amounts of Cd(II) ions removed from human plasma by poly(HEMA–EGDMA)–Cibacron Blue F3GA and poly(HEMA–EGDMA)–Cibacron Blue F3GA–thionein were of 17.5 mg/g and 38.0 mg/g, respectively. Cd(II) ions could be repeatedly adsorbed and desorbed with both types of microspheres without significant loss in their adsorption capacity.  相似文献   
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1. Larvae of antlions (Neuroptera: Myrmeleontidae) and wormlions (Diptera: Vermileonidae) display a convergently evolved sit‐and‐wait hunting strategy of building pitfall traps in sandy areas. This study investigated a sympatric population of antlions and wormlions in the lowland rainforest of Borneo for substrate moisture, particle size and temperature preferences. It was hypothesised that these animals would show different preferences regarding these microhabitat traits. 2. The results showed that antlions had a higher aversion to moisture compared with wormlions, but that wormlions had a higher preference for small‐particle sand. Furthermore, thermal preferences in antlions and wormlions were significantly different, with antlions choosing higher temperatures. 3. The detected differences between antlions and wormlions might contribute to their niche partitioning in the mixed Bornean population and thus facilitate coexistence of these animals. It is possible that the hotter and dryer microhabitat edges are preferred by antlions.  相似文献   
4.
We described the bacterial diversity of walnut grove soils under organic and conventional farming. The bacterial communities of rhizospheric and nonrhizospheric soils of pecan tree (Carya illinoensis K. Koch) were compared considering two phenological stages (sprouting and ripening). Sixteen operational taxonomic units (OTUs) were identified significantly more abundant according to the plant development, only one according to the farming condition, and none according to the soil origin. The OTUs specificaly abundant according to plant development included Actinobateria (2) and Betaproteobacteria (1) related OTUs more abundant at the sprouting stage, while at the fruit ripening (FR) stage the more abundant OTUs were related to Actinobacteria (6), Alphaproteobacteria (6), and unclassified Bacteria (1). The Gaiellaceae OTU18 (Actinobacteria) was more abundant under conventional farming. Thus, our study revealed that the plant development stage was the main factor shaping the bacterial community structure, while less influence was noticed for the farming condition. The bacterial communities exhibited specific metabolic capacities, a large range of carbon sources being used at the FR stage. The identified OTUs specifically more abundant represent indicators providing useful information on soil condition, potential tools for the management of soil bacterial communities.  相似文献   
5.
The aim of this study was to investigate the effect of static magnetic fields (SMF) on reactive oxygen species induced by X‐ray radiation. The experiments were performed on lymphocytes from male albino Wistar rats. After exposure to 3 Gy X‐ray radiation (with a dose rate of 560 mGy/min) the measurement of intracellular reactive oxygen species in lymphocytes, using a fluorescent probe, was done before exposure to the SMF, and after 15 min, 1 and 2 h of exposure to the SMF or a corresponding incubation time. For SMF exposure, 0 mT (50 µT magnetic field induction opposite to the geomagnetic field) and 5 mT fields were chosen. The trend of SMF effects for 0 mT was always opposite that of 5 mT. The first one decreased the rate of fluorescence change, while the latter one increased it. Bioelectromagnetics 34:333–336, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Conformational energies for the N-acetyl-N'-methylamides of the 20 natural amino acids were calculated, including the solvent effects, as functions of the angles phi and psi for rotation of the main chain and for six positions chi 1 of the C alpha-C beta bond in the side chain (fixed values for chi 2, chi 3, ...). The computed energies were used to evaluate the mean-square end-to-end distance and mean-square dipole moment of homopolypeptides of the 20 natural amino acids. Ten proteins and three enzymes of current interest were also studied. Slight differences in both properties are found on taking the effects of solvent into consideration. Comparison with other computational and experimental results is made.  相似文献   
8.
The utilization of guanidino and ureido compounds was studied in several Pseudomonas species. Multiple routes of agmatine catabolism were found. All members of the homology group I of Pseudomonas use the initial deamination of agmatine to carbamoylputrescine which is subsequently converted to putrescine. In Pseudomonas indigofera, the catabolism of agmatine can also occur via an initial hydrolysis of the amidino group to putrescine catalyzed by an agmatine amidinohydrolase. A third pathway was found in Pseudomonas cepacia, namely oxidative deamination producing guanidinobutyraldehyde catalyzed by agmatine dehydrogenase, followed by formation of guanidinobutyrate and removal of urea by guanidinobutyrate amidinohydrolase to produce 4-aminobutyrate. Novel amidino-hydrolases were characterized in P. putida for the utilization of arcaine and audouine, and in P. cepacia for arcaine, homoarginine and guanidinovalerate. Guanidinovalerate amidinohydrolase was also detected in P. doudoroffii. Some of these amidinohydrolases accept more than one substrate, e.g., guanidinobutyrate and guanidinovalerate utilization by P. doudoroffii and P. cepacia, the catabolism of arcaine and audouine by P. putida, and the degradation of arcaine and homoarginine by P. cepacia.  相似文献   
9.
An isolated rat liver was perfused with deoxynivalenol (DON) at a dose of 3 mg in a recirculating perfusion system. To identify glucuronide conjugates equal amounts of bile samples, perfusate and liver homogenates were incubated with and without (control) a β-glucuronidase preparation and analyzed by thin layer chromatography and capillary gas liquid chromatography — chemical ionization mass spectrometry. A total of 40.4% of the administered dose of DON was found to be conjugated with glucuronic acid (perfusate 20.4%, bile 19.2%, liver 0.8%), while only 1.3% of the parent DON (perfusate 1.1%, bile 0.2%) was detected. The cleavage of DON-glucuronide was demonstrated by incubating DON-glucuronide containing bile samples with intestine contents under anaerobic conditions.  相似文献   
10.
Rat brain cortical neurons originate from germinal cells during a period of 6 days immediately before birth. Upon leaving the proliferative layer neurons become irreversibly quiescent. We have previously reported the presence of core histone nonallelic variants in terminally differentiated rat brain cortical neurons. Although the functional significance of core histone variants is unknown, several lines of evidence suggest that the processes of variant replacement could be involved in the structural and functional differentiation of chromatin. Here we describe the changes in core histone composition that occur during postnatal development. The changes in chromatin composition are already apparent at birth, suggesting that the change in synthesis patterns is related to the arrest of cell proliferation and neuron commitment. During postnatal development H2A.2, H2A.x, and H3.3 accumulate, whereas H2A.1, H3.1, and H3.2 decrease. H2A.z is the only variant that remains constant. The time courses of replacement and the observed variant proportions when the variant composition approaches the equilibrium suggest that all H2A variants are synthesized either in germinal cells or in neurons, whereas H3.1 and H3.2 seem to be synthesized only in germinal cells. The extent of the replacement of H3.1 and H3.2 by H3.3 shows that the exchange process affects most of the chromatin. The half-life times of H2A.1 and H3.2 were calculated from their respective exponential decays. Values of 65 days or less and 142 days were found for H2A.1 and H3.2, respectively. The preferential replacement of H2A.1 over H3.2 reinforces the view that the histone core does not degrade as a single unit.  相似文献   
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