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61.
Several studies indicated that biopharmaceuticals based on the recombinant protein E7 of human papillomavirus (HPV) can serve as therapeutic vaccines preventing the development of cancer in women infected with high-risk types of HPV such as HPV16. Here, we report effective extraction and purification of a plant-produced E7GGG-lichenase fusion protein, an HPV16 subunit vaccine candidate, from Nicotiana benthamiana plants, to a high yield. The target contains the modified HPV16 E7 protein internally fused to the surface loop of a truncated, hexa-His- and KDEL-tagged variant of bacterial lichenase, and has been previously shown to possess anti-cancer activity in an animal model. We purified the protein using a combination of immobilized metal-ion affinity chromatography and gel filtration. The achieved purity of the final product was 99% as confirmed by Coomassie or SYPRO Ruby staining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by analytical size exclusion chromatography coupled with multi-angle laser light scattering. The overall yield was 50% corresponding to 0.1g of protein per 1 kg plant biomass. Only slight changes in these parameters were observed during the process scale-up from 50 g to 1 kg of processed leaf biomass.  相似文献   
62.
Successful surfactant removal from wastewater is often limited by the high concentration of the surfactant. The use of advanced oxidation processes can be the key to aid biological treatment of water containing high amounts of surfactants. The present study analyzes the biodegradation of the anionic surfactant sodium dodecylbenzenesulfonate (SDBS) and the effects of its combination with ozonation. SDBS pre‐ozonation favors the metabolism by microorganisms. Experimental results indicate that the application of a concentration of up to 60 μM of ozone for 60 min, prior to contact with microorganisms, increases the percentage of SDBS removed by biodegradation alone. These results demonstrate that the removal of SDBS and of the total organic carbon is increased by the consecutive use of ozonation and biodegradation.  相似文献   
63.
The purpose of this study was to determine taste difference thresholds for monosodium glutamate (MSG) and sodium chloride (NaCl) in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi). Using a two-bottle preference test of brief duration, three animals of each species were presented with four different reference concentrations of 50, 100, 200, and 400 mM of a tastant and tested for their ability to discriminate these from lower concentrations of the same tastant. The just noticeable differences (JNDs), expressed as Weber ratios (DeltaI/I), were found to range from 0.1 to 0.5 for MSG and 0.2 to 0.45 for NaCl in the pigtail macaques, with a significant tendency for higher Weber ratios with higher reference concentrations. In the spider monkeys, JNDs ranged from 0.15 to 0.4 for MSG and 0.1 to 0.25 for NaCl, with Weber ratios staying fairly constant across the reference concentrations tested. Thus, the JNDs were found to be generally similar in both species and to be at least as low as those found in humans for MSG and NaCl, as well as those found in spider monkeys for sucrose. The results support the assumption that both pigtail macaques and spider monkeys may use differences in perceived intensity of MSG and NaCl as a criterion for food selection.  相似文献   
64.
To ascertain the role played by the various liver monocyte-macrophage populations in the course of a viral hemorrhagic fever, fifteen pigs were inoculated intramuscularly with the highly virulent isolate of African Swine Fever Virus (ASFV) Espa?a-70 and slaughtered at 1-7 days post-inoculation (dpi). Samples of liver were fixed in different solutions and routinely processed for morphological, immunohistochemical and ultrastructural studies. Viral antigen (vp73) was detected from 3 dpi onward, mainly in circulating monocytes of sinusoid and Kupffer's cells (KC), as well as in portal macrophages and hepatocytes from 5 dpi. Anti-SWC3 immunolabelled cells were increased from 1 dpi, peaking between 3 and 5 dpi, thereafter declining until the end of the experiment. The significant increase in the number of sinusoidal circulating monocytes and KC expressing IL-1alpha, TNFalpha and IL-6 from 1 dpi, confirmed the secretory activation of these cells. The results show that in the course of an ASFV-induced hemorrhagic syndrome, hepatic macrophage populations undergo major quantitative and biosynthetic changes prior to virus detection, suggesting the existence of a mechanism by which the virus concentrates infectable cells, which subsequently spread the virus around the body.  相似文献   
65.
Pines have been extensively used for land restoration in the Mediterranean basin and in other parts of the world, since the late 19th century. The theoretical basis supporting pine utilisation was its stress-tolerant and pioneer features, and their attributed role of facilitating the development of late-successional hardwoods in the long-term. In the present work, the use of pines and hardwoods in forest restoration is discussed in the frame of the current disturbance regime and social demands for Mediterranean forests. Large pine plantations have recently disappeared because of their sensitivity to fire (e.g., Pinus nigra) or because of the short fire-intervals (e.g., Pinus halepensis). Combined pine and oak plantations are proposed for degraded land restoration on the basis of the complementary features of both groups of species. Seeding and containerised seedling plantation, soil amendments and plantation techniques to reduce transplant shock are evaluated for reforestation under water-stressing conditions, on the basis of several experiments performed in eastern Spain. Both P. halepensis and Quercus ilex are tested.  相似文献   
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Incomplete reproductive isolation and hybridization is relatively frequent in primates. However, no cases of hybridization between formally recognized species have been reported in tamarins (genus Saguinus), a highly specious group of Neotropical primates. Here, we provide evidence from different sources to demonstrate three cases of hybridization in captivity between species of Saguinus distributed west of the Andes (trans-Andean). To do this, we described fur color patterns, genotyped 12 microsatellite loci, sequenced the mitochondrial hypervariable region I, and generated chromosomal R bands for the three formally recognized species and the new hybrids of trans-Andean tamarins. We identified one case of interbreeding between the white-footed tamarin (Saguinus leucopus) and the cotton-top tamarin (S. ?dipus) and two independent reciprocal crosses of S. leucopus and the Geoffroy’s tamarin (S. geoffroyi). All these hybrids exhibit intermediate phenotypes between parental species, and genetic data are consistent with first-generation hybridization. Cytogenetic data suggest that the S. leucopus × S. ?dipus hybrid is sterile, as it is a female with XY karyotype apparently affected by a condition known as gonadal dysgenesis. Trans-Andean tamarin species occur in northwest Colombia with parapatric distributions bounded by major rivers. Potential contact zones, either natural or anthropogenic, might facilitate hybridization in the wild, but this scenario remains to be assessed. Our findings warrant future studies focused on the evolutionary mechanisms of reproductive isolation in tamarins. Given the risk of hybridization, caution should be taken in management and conservation of tamarins.  相似文献   
69.
Representatives of the monophyletic Trentepohliales are widely distributed in the tropics, subtropics, and temperate regions worldwide. They grow in soil, or are epilithic, epiphytic or endophytic. The family comprises approximately 70 species placed in at least four genera (Trentepohlia, Cephaleuros, Phycopeltis and Stomatochroon), with Trentepohlia sensu lato (including Printzina and Physolinum) accounting for half of the species in this family. PCR amplification and sequencing of the 18 SSU rDNA of 18 isolates of the Trentepohliaceae were used to assess the monophyly of the genus Cephaleuros and to determine the phylogenetic relationships among species of Trentepohlia sensu lato. Distance, Parsimony, and Maximum Likelihood analyses indicate that Trentepohlia sensu lato is basal and includes two species recently transferred to Phycopeltis (P. umbrina) and Printzina (P. lagenifera). In contrast, Cephaleuros is a derived monophyletic clade. Analysis of isolates of C. virescens, from the USA, Taiwan, and South Africa indicate that this taxon may consist of different species sharing a convergent morphology. The results of this study have implications for the taxonomy of the genera.  相似文献   
70.
Yee  KK; Costanzo  RM 《Chemical senses》1998,23(5):513-519
Following recovery from olfactory nerve transection, animals regain their ability to discriminate between odors. Odor discrimination is restored after new neurons establish connections with the olfactory bulb. However, it is not known if the new connections alter odor quality perception. To address this question, 20 adult hamsters were first trained to discriminate between cinnamon and strawberry odors. After reaching criterion (> or = 90% correct response), half of the animals received a bilateral nerve transection (BTX) and half a surgical sham procedure. Animals were not tested again until day 40, a point in recovery when connections are re-established with the bulb. When BTX animals were tested without food reinforcement, they could not perform the odor discrimination task. Sham animals, however, could discriminate, demonstrating that the behavioral response had not been extinguished during the 40 day period. When reinforcement was resumed, BTX animals were able to discriminate between cinnamon and strawberry after four test sessions. In addition, their ability to discriminate between these two familiar odors was no different than that of BTX and sham animals tested with two novel odors, baby powder and coffee. These findings suggest that, after recovery from nerve transection, there are alterations in sensory perception and that restoration of odor quality discrimination requires that the animal must again learn to associate individual odor sensations with a behavioral response.   相似文献   
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