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111.
The ecology of Escherichia coli O157:H7 is not well understood. The aims of this study were to determine the prevalence of and characterize E. coli O157:H7 associated with houseflies (HF). Musca domestica L. HF (n = 3,440) were collected from two sites on a cattle farm over a 4-month period and processed individually for E. coli O157:H7 isolation and quantification. The prevalence of E. coli O157:H7 was 2.9 and 1.4% in HF collected from feed bunks and a cattle feed storage shed, respectively. E. coli O157:H7 counts ranged from 3.0 × 101 to 1.5 × 105 CFU among the positive HF. PCR analysis of the E. coli O157:H7 isolates revealed that 90.4, 99.2, 99.2, and 100% of them (n = 125) possessed the stx1, stx2, eaeA, and fliC genes, respectively. Large populations of HF on cattle farms may play a role in the dissemination of E. coli O157:H7 among animals and to the surrounding environment. 相似文献
112.
A survey was conducted with the aim to document the indigenous information of Charkotli Hills, Batkhela District, Malakand,
Pakistan. The area has rich vegetation and a high potential for ethnobotanical utilization. Information was collected on various
traditional uses of 100 plants distributed over 49 families, of which 43 families were of dicot, 2 of monocot, 2 of pteridophyta,
and 1 of gymnosperms. Most plants have more than one local use. Sixty-six plants were found to be medicinal species, 21 fruit
and edible seed species, 11 furniture species, 18 fodder or forage species, 12 vegetable species, 12 fuel species, 11 thatching
and building species, 5 hedge or fencing species, 5 timber wood species, 5 poisonous plants, 3 species used in ketchup, 2
fixed oil yielding species, 2 miswak species, 2 species for making sticks for cattle and defense purposes, 2 species cultivated
for ornamental purposes, 2 species used as mehindi by girls, 1 irritant species, 1 species for the making of Salai (a little
stick for applying ‘surma’ to the eyes), 1 species for tanning, 1 species used as refresher in milk pots, 1 species giving
gum used as chewing gum, and 1 species used as insect repellent. The area is under heavy pressure of deforestation and overgrazing,
which have reduced the regeneration of woody plants. Proper ecological management is required to protect the wildlife and
ethnobotanical resources for the coming generations. 相似文献
113.
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115.
Tipu Muhammad Imran Ashraf Muhammad Yasin Sarwar Nadeem Akhtar Muhammad Shaheen Muhammad Rashid Ali Sajjad Damalas Christos A. 《Journal of Plant Growth Regulation》2021,40(2):774-786
Journal of Plant Growth Regulation - Nickel (Ni) element is strongly phytotoxic at high concentrations for several plants, but due to its dual behavior and complicated chemistry, it has received... 相似文献
116.
Zohaib Abbas Fariha Arooj Ihsan Elahi Zaheer Muhammad Rizwan Muhammad Ahsan Riaz 《International journal of phytoremediation》2019,21(13):1356-1367
AbstractIn the present study, the effectiveness of water hyacinth and water lettuce was tested for the phytoremediation of landfill leachate for the period of 15?days. Fifteen plastic containers were used in experimental setup where aquatic plants were fitted as a floating bed with the help of thermo-pole sheet. It was observed that both plants significantly (p?<?0.05/p?<?0.01/p?<?0.001) reduce the physicochemical parameters pH, TDS, BOD, COD and heavy metals like Zn, Pb, Fe, Cu and Ni from landfill leachate. Maximum reduction in these parameters was obtained at 50% and 75% landfill leachate treatment and their removal rate gradually increased from day 3 to day 15 of the experiment. The maximum removal rate for heavy metals such as for Zn (80–90%), Fe (83–87%) and Pb (76–84%) was attained by Eichhornia crassipes and Pistia stratiotes. Value of bioconcentration and translocation factor was less than 1 which indicates the low transport of heavy metals from roots to the above-ground parts of the plants. Both these plants accumulate heavy metals inside their body without showing much reduction in growth and showing tolerance to all the present metals. Therefore, results obtained from the study suggest that these aquatic plants are suitable candidate for the removal of pollution load from landfill leachate. 相似文献
117.
Ivo H. J. Ploemen Miguel Prudêncio Bruno G. Douradinha Jai Ramesar Jannik Fonager Geert-Jan van Gemert Adrian J. F. Luty Cornelus C. Hermsen Robert W. Sauerwein Fernanda G. Baptista Maria M. Mota Andrew P. Waters Ivo Que Clemens W. G. M. Lowik Shahid M. Khan Chris J. Janse Blandine M. D. Franke-Fayard 《PloS one》2009,4(11)
The quantitative analysis of Plasmodium development in the liver in laboratory animals in cultured cells is hampered by low parasite infection rates and the complicated methods required to monitor intracellular development. As a consequence, this important phase of the parasite''s life cycle has been poorly studied compared to blood stages, for example in screening anti-malarial drugs. Here we report the use of a transgenic P. berghei parasite, PbGFP-Luccon, expressing the bioluminescent reporter protein luciferase to visualize and quantify parasite development in liver cells both in culture and in live mice using real-time luminescence imaging. The reporter-parasite based quantification in cultured hepatocytes by real-time imaging or using a microplate reader correlates very well with established quantitative RT-PCR methods. For the first time the liver stage of Plasmodium is visualized in whole bodies of live mice and we were able to discriminate as few as 1–5 infected hepatocytes per liver in mice using 2D-imaging and to identify individual infected hepatocytes by 3D-imaging. The analysis of liver infections by whole body imaging shows a good correlation with quantitative RT-PCR analysis of extracted livers. The luminescence-based analysis of the effects of various drugs on in vitro hepatocyte infection shows that this method can effectively be used for in vitro screening of compounds targeting Plasmodium liver stages. Furthermore, by analysing the effect of primaquine and tafenoquine in vivo we demonstrate the applicability of real time imaging to assess parasite drug sensitivity in the liver. The simplicity and speed of quantitative analysis of liver-stage development by real-time imaging compared to the PCR methodologies, as well as the possibility to analyse liver development in live mice without surgery, opens up new possibilities for research on Plasmodium liver infections and for validating the effect of drugs and vaccines on the liver stage of Plasmodium. 相似文献
118.
Dawood Muhammad Fei Chen Jing Zhao Guoping Zhang Feibo Wu 《International journal of phytoremediation》2009,11(6):558-574
A pot experiment was conducted to study the performance of EDTA and citric acid (CA) addition in improving phytoextraction of Cd, Cu, Pb, and Cr from artificially contaminated soil by T. angustifolia. T. angustifolia showed the remarkable resistance to heavy metal toxicity with no visual toxic symptom including chlorosis and necrosis when exposed to metal stress. EDTA-addition significantly reduced plant height and biomass, compared with the control, and stunted plant growth, while 2.5 and 5 mM CA addition induced significant increases in root dry weight. EDTA, and 5 and 10 mM CA significantly increased shoot Cd, Pb, and Cr concentrations compared with the control, with EDTA being more effective. At final harvest, the highest shoot Cd, Cr, and Pb concentrations were recorded in the treatment of 5 mM EDTA addition, while maximal root Pb concentration was found at the 2.5 mM CA treatment. However, shoot Cd accumulation in the 10 mM CA treatment was 36.9% higher than that in 2.5 mM EDTA, and similar with that in 10 mM EDTA. Shoot Pb accumulation was lower in 10 mM CA than that in EDTA treatments. Further, root Cd, Cu, and Pb accumulation of CA treatments and shoot Cr accumulation in 5 or 10 mM CA treatments were markedly higher than that of control and EDTA treatments. The results also showed that EDTA dramatically increased the dissolution of Cu, Cr, Pb, and Cd in soil, while CA addition had less effect on water-soluble Cu, Cr, and Cd, and no effect on Pb levels. It is suggested that CA can be a good chelator candidate for T. angustifolia used for environmentally safe phytoextraction of Cd and Cr in soils. 相似文献
119.
Liang Chengcheng Raza Sayed Haidar Abbas Naqvi Muhammad Abuzar Raza Feng Yanrong Khan Rajwali Mohammedsaleh Zuhair M. Shater Abdullah F. Al-ahmadi Bassam M. Saleh Fayez M. Bilal Muhammad Ahsan Zan Linsen 《Biochemical genetics》2022,60(2):543-557
Biochemical Genetics - The Long non-coding RNA (lncRNA) expression profile data of ten samples including human Mesenchymal Stem Cell (MSC) adipogenic differentiation 0, 3, and 6 days from... 相似文献
120.
Crystal structure of peptidoglycan recognition protein SA in Apis mellifera (Hymenoptera: Apidae) 下载免费PDF全文
Yanjie Liu Xiaomeng Zhao Muhammad Naeem Jiandong An 《Protein science : a publication of the Protein Society》2018,27(4):893-897
Peptidoglycan recognition protein SA (PGRP‐SA) is a key pattern recognition receptor in the insect innate immune system. PGRP‐SA can bind to bacterial PGN and activate the Toll pathway, which triggers the expression and release of antimicrobial peptides to prevent bacterial infection. Here, we report the first structure of Apis mellifera PGRP‐SA from Hymenoptera at 1.86 Å resolution. The overall architecture of Am‐PGRP‐SA was similar to the Drosophila PGRP‐SA; however, the residues involved in PGN binding groove were not conserved, and the binding pocket was narrower. This structure gives insight into PGN binding characteristics in honeybees. 相似文献