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991.
992.
Moore C Rana S Coulter C 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,852(1-2):459-464
Tetrahydrocannabinol (THC) is an important psychoactive ingredient in marijuana, which is the most widely used illegal recreational drug in the USA. Since it is generally smoked, the constituents of the plant material, as well as THC may be present in oral fluid specimens collected for the purposes of drug testing. We present an analytical procedure for the simultaneous determination of the pyrolytic precursor Delta(9)-tetrahydrocannabinolic acid A, tetrahydrocannabinol, cannabinol and cannabidiol in human oral fluid specimens using gas chromatography mass spectrometry (GC/MS). Solid phase extraction and GC/MS/EI with selected ion monitoring were used, and the linearity of the method ranged from 0-16 ng/mL of neat oral fluid. The recovery of the cannabinoids from the collection pad into the transportation buffer was greater than 70% for all cannabinoids tested at 4 ng/mL, and the intra- and inter-day precision was less than 10.3 and 15.2% for all analytes. The stability of the drugs in oral fluid and of the extracted derivatives was investigated. The procedure was applied to oral fluid specimens taken from habitual marijuana smokers. We have previously reported the presence of the metabolite 11-nor-Delta(9)-tetra-hydrocannabinol-9-carboxylic acid in oral fluid, but this is the first report of the plant constituent 2-carboxy-THC being detected in saliva. 相似文献
993.
Moore C Rana S Coulter C 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):370-375
Analytical procedures for the determination of meperidine, tramadol and oxycodone in oral fluid have been developed and validated using gas chromatography-mass spectrometry (GC/MS) following initial screening with enzyme linked immunosorbent assay (ELISA). The oral fluid samples were collected using the Quantisal device, and any drugs present were quantified using mixed mode solid-phase extraction and electron impact GC/MS. For confirmation, three ions were monitored and two ion ratios determined, which were within 20% of those of the known calibration standards. The limits of quantitation were 10 ng/mL; the intra-day precision of the assays (n=5) was 2.33%, 1.00% and 7.61%; inter-day precision 2.48%, 2.44% and 5.8% (n=10) for meperidine, tramadol and oxycodone, respectively. The percentage recovery of the drugs from the collection pads was 86.7%, 87.7% and 96.6%, respectively (n=6). The methods were applied to specimens obtained during research studies in the USA. 相似文献
994.
Siddiqui N Pandeya SN Khan SA Stables J Rana A Alam M Arshad MF Bhat MA 《Bioorganic & medicinal chemistry letters》2007,17(1):255-259
A series of sulphonamide derivatives (1-11) were synthesized in good yield and evaluated for their possible anticonvulsant activity and neurotoxic study. The structures of the synthesized compounds were confirmed on the basis of their spectral data and elemental analysis. Majority of the compounds were active in MES and scPTZ tests. All the compounds were less toxic than the standard drug phenytoin. 相似文献
995.
Islam Dad Buneri Masarrat Yousuf Mohammad Attaullah Saifullah Afridi Syed Ishtiaq Anjum Habibullah Rana Naveed Ahmad Muhammad Amin Muhammad Tahir Mohammad Javed Ansari 《Saudi Journal of Biological Sciences》2019,26(2):281-285
Cedrus deodara (deodar) is practically used, as insect repellent, in the northern areas of Pakistan but no data available therefore this study was conducted to evaluate the effectiveness of deodar oil as an alternate of conventional insecticides against the larval pest stage of mealworm beetle (Tenebrio molitor), by feeding method. The aim of the study was to investigate the effectiveness of deodar oil as an alternate of conventional insecticides against the larval pest stage of mealworm beetle (Tenebrio molitor), by feeding method. All tested chemicals showed efficacy against the pests. The LC50 was determined by probit analysis and was found to be 3.41, 0.086 and 0.023% of larvae treated with deodar oil, Carbosulfan and Imidacloprid respectively The LC50 treated larvae were subjected to the evaluation of protein activity, qualitatively and quantitatively. The protein level in tested insects was enhanced when treated with Imidacloprid, Carbosulfan and deodar oil. The electrophoretic profile of treated insects showed more bands in insects treated with Cedrus deodara oil. This electrophoretic profile appeared in 4, 5, 7 and 8 bands for tested chemicals including control. Antifeedant activity was observed for C. deodara as larvae were deterred to feed on the food found in the container. 相似文献
996.
Johanna Chiche Julie Reverso-Meinietti Annabelle Mouchotte Camila Rubio-Patiño Rana Mhaidly Elodie Villa Jozef P. Bossowski Emma Proics Manuel Grima-Reyes Agnès Paquet Konstantina Fragaki Sandrine Marchetti Josette Briere Damien Ambrosetti Jean-François Michiels Thierry Jo Molina Christiane Copie-Bergman Jacqueline Lehmann-Che Jean-Ehrland Ricci 《Cell metabolism》2019,29(6):1243-1257.e10
997.
Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape. 相似文献
998.
The limited information available regarding the gene structure of adenylyl cyclases (AC), which catalyze the synthesis of cAMP, suggests a complex arrangement with many exons and large introns such that molecular techniques to define these gene structures are time- and labor-intensive. We report here the use of a computer-based approach involving the assembly of fragmented sequence data generated by the Human Genome Project and nucleic acid analysis software to decipher the gene structure of human and murine AC 6 and other human AC isoforms (ACs 3, 7, and 8). The results, which document 21 exons in human and murine AC 6, human AC 3, 18 exons in AC 8, and 24 exons in AC 7, show substantial conservation of exon organization in the AC family and in particular regions of the AC protein. Application of such in silico methods should prove useful to characterize genes for other ACs and protein families and data provided here should facilitate studies of polymorphisms in AC genes. 相似文献
999.
Peter Robinson Rana el Kaliouby 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1535):3441-3447
The importance of emotional expression as part of human communication has been understood since Aristotle, and the subject has been explored scientifically since Charles Darwin and others in the nineteenth century. Advances in computer technology now allow machines to recognize and express emotions, paving the way for improved human–computer and human–human communications.Recent advances in psychology have greatly improved our understanding of the role of affect in communication, perception, decision-making, attention and memory. At the same time, advances in technology mean that it is becoming possible for machines to sense, analyse and express emotions. We can now consider how these advances relate to each other and how they can be brought together to influence future research in perception, attention, learning, memory, communication, decision-making and other applications.The computation of emotions includes both recognition and synthesis, using channels such as facial expressions, non-verbal aspects of speech, posture, gestures, physiology, brain imaging and general behaviour. The combination of new results in psychology with new techniques of computation is leading to new technologies with applications in commerce, education, entertainment, security, therapy and everyday life. However, there are important issues of privacy and personal expression that must also be considered. 相似文献
1000.
Chironomid larvae (2.0 individuals/cm2) were introduced in sediment–water microcosms of 3.0 l capacity to assess the impact of bioturbation on phosphorus flux across sediment–water interface, under different nutrient-enriched conditions. Recruitment of chironomid resulted in 21% and 19% increase in aquatic orthophosphate and nitrate quanta, respectively, with concomitant decrease in nutrient concentration in the sediment compared to macrofauna-free controls under mesotrophic condition. It implied that cost of fertilizer for biological production could be curtailed by at least 19–21% by recovering nutrients stored in the sediment pool. Bioturbation-induced orthophosphate flux under chironomid impacted mesotrophic treatment was 2.3- and 1.8-fold greater than that under bioturbated eutrophic treatment, suggesting that the macrofaunal impact was reduced in the presence of higher nutrient load perhaps due to physicochemical stressors under eutrophic condition. Nevertheless, chironomid larvae can further accelerate nutrient enrichment in the eutrophic system that may invite a “snow ball effect” towards a hypereutrophic one. The counts of both heterotrophic and phosphate solubilizing bacteria show strong positive correlation with orthophosphate concentration in water and the correlation also exists between organic carbon concentration in sediment and phosphate in overlying water. This implied that the accelerated phosphate flux was the result of coordinated eco-engineering activities of chironomid larvae and microbe-mediated mineralization of organic matter. 相似文献