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351.
Origanum (Lamiaceae) comprises a number of essential oil‐rich species that have been used by humans for centuries. Today, the four species of section Majorana (O. onites, O. dubium, O. majorana and O. syriacum) are amongst the most widely used. Despite the importance of this section, phylogenetic relationships and species boundaries amongst its four taxa are unclear. In the present investigation, we used DNA sequence data from two nuclear regions [internal transcribed spacer (ITS) and 1‐deoxy‐d ‐xylulose 5‐phosphate synthase (DXS)] as well as five microsatellite loci to test the taxonomic status of the four species of section Majorana. The combined DNA data revealed O. onites and O. syriacum as the older species in the section. Origanum majorana descends directly from O. syriacum. Origanum dubium was found to be of hybridogenous origin showing attributes of O. onites, O. syriacum and a third, unknown, Origanum species. Both sequence and microsatellite analyses provided evidence for recent hybridization between O. onites and O. dubium in Turkey. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013 , 171 , 667–686.  相似文献   
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353.
Acute ultraviolet-B (UV-B) irradiation is known to act as an initiator in the formation of reactive oxygen species. These oxygen products are highly reactive and they are able to cause irreversible damage to cellular components. Oxygen free radicals are normally neutralized by very efficient systems in the body. These include antioxidant enzymes like superoxide dismutase (SOD). In a healthy subject, there is a balance between free radicals and the levels of antioxidants. In some pathological conditions such as oxidative stress, the level of antioxidants is significantly reduced. The skin contains relatively high levels of zinc (Zn), an essential element known to be a cofactor in some metabolic pathways. Zinc has also been reported to have antioxidant properties. In the present study, we investigated the effect of ginkgo biloba extract (Gbe), a potent free-radical scavenger, on UV-B-irradiated skin by measuring SOD activity and Zn levels in the skin, before and after treatment. The SOD activity was decreased after UV-B exposure, in comparison with the control group (p<0.05). After Gbe treatment, the SOD activity increased (p<0.05) as compared with the untreated UV-B irradiated group. The Zn levels changed in the same pattern as the SOD activity values.  相似文献   
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355.
Effects of juglone on seedling growth of cucumber (Cucumis sativus cv. Beith Alpha) with respect to physiological and anatomical parameters were investigated. Growth parameters (seedling elongation, fresh and dry weights) were reduced by 1 mM juglone. Juglone also decreased chlorophyll a and b contents and reduced some anatomical tissues (xylem vessel and bundle radius of stem, stomata length and stomata number of the cotyledons). The anatomical changes in stem and cotyledon of the seedlings were related to growth inhibiting effect of juglone. On the other hand, increase in catecholase and tyrosinase activities by the effect of juglone were also recorded.  相似文献   
356.
The administration separately and sequentially of carbenicillin and gentamicin eradicated Ps. aeruginosa infections, during the period over which they were given, in all of 25 critically ill patients. Electron microscopy revealed differences in the action of these two antibiotics against Ps. aeruginosa in vitro. Culture studies showed synergism between them and destruction by gentamicin of the carbenicillin-induced long, filamentous form of the organism.  相似文献   
357.
Predictions of added resistance and the effective power of ships were made for varying barnacle fouling conditions. A series of towing tests was carried out using flat plates covered with artificial barnacles. The tests were designed to allow the examination of the effects of barnacle height and percentage coverage on the resistance and effective power of ships. The drag coefficients and roughness function values were evaluated for the flat plates. The roughness effects of the fouling conditions on the ships’ frictional resistances were predicted. Added resistance diagrams were then plotted using these predictions, and powering penalties for these ships were calculated using the diagrams generated. The results indicate that the effect of barnacle size is significant, since a 10% coverage of barnacles each 5 mm in height caused a similar level of added power requirements to a 50% coverage of barnacles each 1.25 mm in height.  相似文献   
358.
We present a novel computational model that detects temporal configurations of a given human neuronal pathway and constructs its artificial replication. This poses a great challenge since direct recordings from individual neurons are impossible in the human central nervous system and therefore the underlying neuronal pathway has to be considered as a black box. For tackling this challenge, we used a branch of complex systems modeling called artificial self-organization in which large sets of software entities interacting locally give rise to bottom-up collective behaviors. The result is an emergent model where each software entity represents an integrate-and-fire neuron. We then applied the model to the reflex responses of single motor units obtained from conscious human subjects. Experimental results show that the model recovers functionality of real human neuronal pathways by comparing it to appropriate surrogate data. What makes the model promising is the fact that, to the best of our knowledge, it is the first realistic model to self-wire an artificial neuronal network by efficiently combining neuroscience with artificial self-organization. Although there is no evidence yet of the model’s connectivity mapping onto the human connectivity, we anticipate this model will help neuroscientists to learn much more about human neuronal networks, and could also be used for predicting hypotheses to lead future experiments.  相似文献   
359.
Sunitinib is a multitargeted kinase inhibitor that inhibits many receptor tyrosine kinases and has been used in the treatment of gastrointestinal stromal tumors, metastatic renal cell carcinoma, and pancreatic neuroendocrine tumors. In this study, the effects of sunitinib given to rats, both alone and after stress with cisplatin, were investigated. The animals were divided into four groups – (1) control group (C) administered interperitoneally with a single dose 0.9 % saline, (2) Cis group administered a single dose (7 mg/kg) of cisplatin, (3) Sun group administered 10 mg/kg sunitinib for seven days, and (4) Cis+Sun group administered 10 mg/kg sunitinib for seven days after a single dose (7 mg/kg) of cisplatin. After these applications, the rats were sacrificed, and blood and tissue samples were taken for biochemical and histopathological evaluations. Sunitinib did not show any effect on urea, creatine, and kidney IL1β and TGF-β3 expression levels when administered alone; it increased ALT, AST, and IL-38 levels. When sunitinib was given to the cisplatin-induced rats, it was observed that the increase in ALT, AST, and IL-38 levels increased more than the rats that was given only sunitinib. According to the data obtained, sunitinib does not cause a significant change in kidney tissue under both normal and stress conditions, while it creates stress in liver tissue. In addition, its toxicity in the liver becomes more certain as a result of its combination with cisplatin.  相似文献   
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