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81.
82.
Champica K. Bodinayake Ajith DeS Nagahawatte Vasantha Devasiri Niroshana J. Dahanayake Gaya B. Wijayaratne Nayani P. Weerasinghe Madureka Premamali Tianchen Sheng Bradly P. Nicholson Harshanie A. Ubeysekera Ruvini MP Kurukulasooriya Aruna D. de Silva Truls
stbye Christopher W. Woods L Gayani Tillekeratne 《PLoS neglected tropical diseases》2021,15(12)
BackgroundHealthcare systems in dengue-endemic countries are often overburdened due to the high number of patients hospitalized according to dengue management guidelines. We systematically evaluated clinical outcomes in a large cohort of patients hospitalized with acute dengue to support triaging of patients to ambulatory versus inpatient management in the future.Methods/Principal findingsFrom June 2017- December 2018, we conducted surveillance among children and adults with fever within the prior 7 days who were hospitalized at the largest tertiary-care (1,800 bed) hospital in the Southern Province, Sri Lanka. Patients who developed platelet count ≤100,000/μL (threshold for hospital admission in Sri Lanka) and who met at least two clinical criteria consistent with dengue were eligible for enrollment. We confirmed acute dengue by testing sera collected at enrollment for dengue NS1 antigen or IgM antibodies. We defined primary outcomes as per the 1997 and 2009 World Health Organization (WHO) classification criteria: dengue hemorrhagic fever (DHF; WHO 1997), dengue shock syndrome (DSS; WHO 1997), and severe dengue (WHO 2009). Overall, 1064 patients were confirmed as having acute dengue: 318 (17.4%) by NS1 rapid antigen testing and 746 (40.7%) by IgM antibody testing. Of these 1064 patients, 994 (93.4%) were adults ≥18 years and 704 (66.2%) were male. The majority (56, 80%) of children and more than half of adults (544, 54.7%) developed DHF during hospitalization, while 6 (8.6%) children and 22 (2.2%) adults developed DSS. Overall, 10 (14.3%) children and 113 (11.4%) adults developed severe dengue. A total of 2 (0.2%) patients died during hospitalization.ConclusionsOne-half of patients hospitalized with acute dengue progressed to develop DHF and a very small number developed DSS or severe dengue. Developing an algorithm for triaging patients to ambulatory versus inpatient management should be the future goal to optimize utilization of healthcare resources in dengue-endemic countries. 相似文献
83.
The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region. 相似文献
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Responses of aquatic macrophytes to leaf herbivory may differ from those documented for terrestrial plants, in part, because
the potential to maximize growth following herbivory may be limited by the stress of being rooted in flooded, anaerobic sediments.
Herbivory on aquatic macrophytes may have ecosystem consequences by altering the allocation of nutrients and production of
biomass within individual plants and changing the quality and quantity of aboveground biomass available to consumers or decomposers.
To test the effects of leaf herbivory on plant growth and production, herbivory of a dominant macrophyte, Nymphaea odorata, by chrysomelid beetles and crambid moths was controlled during a 2-year field experiment. Plants exposed to herbivory maintained,
or tended to increase, biomass and aboveground net primary production relative to controls, which resulted in 1.5 times more
aboveground primary production entering the detrital pathway of the wetland. In a complementary greenhouse experiment, the
effects of simulated leaf herbivory on total plant responses, including biomass and nutrient allocation, were investigated.
Plants in the greenhouse responded to moderate herbivory by maintaining aboveground biomass relative to controls, but this
response occurred at the expense of belowground growth. Results of these studies suggest that N. odorata may tolerate moderate levels of herbivory by reallocating biomass and resources aboveground, which in turn influences the
quantity, quality and fate of organic matter available to herbivores and decomposers. 相似文献
86.
Michael D. Woodrow Stuart P. Ballantine Michael D. Barker Beth J. Clarke John Dawson Tony W. Dean Christopher J. Delves Brian Evans Sharon L. Gough Steven B. Guntrip Stuart Holman Duncan S. Holmes Michael Kranz Mika K. Lindvaal Fiona S. Lucas Margarete Neu Lisa E. Ranshaw Yemisi E. Solanke Don O. Somers Peter Ward Joanne O. Wiseman 《Bioorganic & medicinal chemistry letters》2009,19(17):5261-5265
Crystallography driven optimisation of a lead derived from similarity searching of the GSK compound collection resulted in the discovery of quinoline-3-carboxamides as highly potent and selective inhibitors of phosphodiesterase 4B. This series has been optimized to GSK256066, a potent PDE4B inhibitor which also inhibits LPS induced production of TNF-α from isolated human peripheral blood mononuclear cells with a pIC50 of 11.1. GSK256066 also has a suitable profile for inhaled dosing. 相似文献
87.
88.
Helen C. Rees Ben C. Maddison Jonathan P. Owen Garry C. Whitelam Kevin C. Gough 《Molecular biotechnology》2009,41(3):254-262
Reagents that can precipitate the disease-associated prion protein (PrPSc) are vital for the development of high sensitivity tests to detect low levels of this disease marker in biological material.
Here, a range of minerals are shown to precipitate both ovine cellular prion protein (PrPC) and ovine scrapie PrPSc. The precipitation of prion protein with silicon dioxide is unaffected by PrPSc strain or host species and the method can be used to precipitate bovine BSE. This method can reliably concentrate protease-resistant
ovine PrPSc (PrPres) derived from 1.69 μg of brain protein from a clinically infected animal diluted into either 50 ml of buffer or 15 ml of
plasma. The introduction of a SiO2 precipitation step into the immunological detection of PrPres increased detection sensitivity by over 1,500-fold. Minerals such as SiO2 are readily available, low cost reagents with generic application to the concentration of diseases-associated prion proteins. 相似文献
89.
Background
Exposure of cells to environmental stress conditions can lead to the interruption of several intracellular processes, in particular those performed by macromolecular complexes such as the spliceosome. 相似文献90.