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831.
Roel Bosma Ahmad Syafei Sidik Paul van Zwieten Anugrah Aditya Leontine Visser 《Wetlands Ecology and Management》2012,20(2):89-99
Around 1990, when in other countries mangrove protection took off, massive conversion of mangrove forest into shrimp ponds
started in the Mahakam delta. To identify constraints to and options for sustainable management we analysed institutions and
constraints with stakeholders. In 3 sites we used participatory tools and a complementary survey to assess the livelihood
framework. Since 1970, ponds for shrimp farming gradually replaced 75% of mangrove forested area. After 2004, recovery of
mangrove took off, as, mainly due to low shrimp yields, ponds were abandoned. In 2008, 54% of the delta was dedicated to ponds
for shrimp production. Around 80% of livelihood activities of pond-farmers, pond caretakers, and fishermen was related to
mangroves. The involvement of men and women in these activities varied between sites and types. Poor households depended more
on mangroves. Most activities resulted in seasonal income peaks; only a few activities resulted in a full daily livelihood.
Ponds, on the other hand, provide 50% of households’ livelihood, but this remains vulnerable in the context of the risky shrimp
production. Skewed land holding, unequal sharing of benefits, competing claims and vested interests of stakeholders pose a
great challenge to a transition to a more sustainable use of the mangrove area. In particular, ponds located on peat soils
are non-sustainable and would require full restoration into mangrove; ponds on other soils could best be transformed into
a mixed mangrove-pond system using a ‘green-water’ technology. 相似文献
832.
LF Chin SM Kong HL Seng YL Tiong KE Neo MJ Maah AS Khoo M Ahmad TS Hor HB Lee SL San SM Chye CH Ng 《Journal of biological inorganic chemistry》2012,17(7):1093-1105
Two ternary Zn(II) complexes, with 1,10-phenanthroline (phen) as the main ligand and a carboxylate-containing ligand [dipicolinate (dipico) or L-threoninate (L-Thr)] as the subsidiary ligand, were prepared and characterized by elemental analysis, Fourier transform IR, UV, and fluorescence spectroscopy, X-ray diffraction, molar conductivity, and electrospray ionization mass spectrometry. X-ray structure analysis shows that both [Zn(phen)(dipico)(H(2)O)]·H(2)O (1) and [Zn(phen)(L-Thr)(H(2)O)Cl]·2H(2)O (2) have octahedral geometry about the Zn(II) atom. Both complexes can inhibit topoisomerase I, and have better anticancer activity than cisplatin against nasopharyngeal cancer cell lines, HK1 and HONE-1, with concentrations causing 50?% inhibition of cell proliferation (IC(50)) in the low micromolar range. Complex 2 has the highest therapeutic index for HK1. Both Zn(II) complexes can induce cell death by apoptosis. Changing the subsidiary ligand in the Zn(II) complexes affects the UV-fluorescence spectral properties of the coordinated phen ligand, the binding affinity for some DNA sequences, nucleobase sequence-selective binding, the phase at which cell cycle progression was arrested for treated cancer cells, and their therapeutic index. 相似文献
833.
Chloroplast transformation offers an exciting platform for the safe, inexpensive and large-scale production of recombinant
proteins in plants. An important advantage for the isolation of proteins produced in the chloroplast would be the use of affinity
tags for rapid purification by affinity chromatography. To date, only His-tags have been used. In this study, we have tested
the feasibility of expressing two additional affinity tags: glutathione-S-transferase (GST) and a His-tagged derivative of the maltose-binding protein (His6-MBP). By using the chloroplast 16S rRNA promoter and 5′ untranslated region of phage T7 gene 10, GST and His6-MBP were expressed in homoplastomic tobacco plants at approximately 7% and 37% of total soluble protein, respectively. GST
could be purified by one-step-affinity purification using a glutathione column. Much better recoveries were obtained for His6-MBP by using a twin-affinity purification procedure involving first immobilised nickel followed by binding to amylose. Interestingly,
expression of GST led to cytoplasmic male sterility. Overall, our work expands the tools available for purifying recombinant
proteins from the chloroplast. 相似文献
834.
835.
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified
polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA
fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence
of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction
tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible
method for identifying and authentication of C. roseus. 相似文献
836.
This article presents an overview of the mechanism of chromium (Cr) stress in plants. Toxic effects of Cr on plant growth and development depend primarily on its valence state. Cr(VI) is highly toxic and mobile whereas Cr(III) is less toxic. Cr-induced oxidative stress involves induction of lipid peroxidation in plants that cause severe damage to cell membranes which includes degradation of photosynthetic pigments causing deterioration in growth. The potential of plants with the adequacy to accumulate or to stabilize Cr compounds for bioremediation of Cr contamination has gained engrossment in recent years. 相似文献
837.
838.
Zahoor Ahmad Mohamed A. M. Abd-Elbasit Mitsuhiro Inoue Hiroshi Yasuda Toshimasa Honna Sadahiro Yamamoto 《Soil & Sediment Contamination》2012,21(2):207-226
To control the dissolved reactive phosphorus (DRP) concentration in a soil solution, a number of soil amendments were tested. In the current study, Blast Furnace Slag (BFS) and Water Treatment Residues (WTR) were tested on bare soil under two rainfall intensities and two soil roughness levels. The soil was fertilized with P (KH2PO4) at a rate of 400 kg ha?1 while BFS and WTR were applied at a rate of 5 g per 100 g of soil. Two soil roughness levels were exposed to artificial rainfall intensities of 30 and 65 mm h?1. Three rainfall events were performed on each treatment. The runoff water generated over an area of 0.5 m2 with a slope of 8% was collected at different time intervals and analyzed for DRP, Al, Fe, and K concentrations. The results showed that, regardless of rainfall intensity and soil roughness, the concentration of DRP in the runoff water increased with increasing runoff time from the unamended plots. However, in the BFS- and WTR-amended soils, the DRP concentration decreased with runoff time. Dissolved reactive P and DRP loads were the lowest from the WTR-amended plots, followed by the control and the BFS treatment plots. Water treatment residues reduced the mean DRP concentration by 27.3% and the DRP load by 32% compared to unamended plots. The two rainfall intensities significantly affected the DRP concentration and load. Under the low rainfall intensity, the DRP concentration and load were higher compared to the high rainfall intensity. The overall DRP concentration was not affected by changes in soil roughness. However, the DRP loads were higher from the plots with low soil roughness levels, especially during the first and second runs. Both the BFS and WTR were also effective in reducing the DRP concentrations in the drain water collected during the runoff events. The concentrations of Al, Fe, and K in the runoff water were not affected by the soil amendments. However, the electrical conductivity and pH readings were higher from the BFS-amended plots. 相似文献
839.
ML De Leoz SC Gaerlan JS Strum LM Dimapasoc M Mirmiran DJ Tancredi JT Smilowitz KM Kalanetra DA Mills JB German CB Lebrilla MA Underwood 《Journal of proteome research》2012,11(9):4662-4672
Breast milk is the ideal nutrition for term infants but must be supplemented to provide adequate growth for most premature infants. Human milk oligosaccharides (HMOs) are remarkably abundant and diverse in breast milk and yet provide no nutritive value to the infant. HMOs appear to have at least two major functions: prebiotic activity (stimulation of the growth of commensal bacteria in the gut) and protection against pathogens. Investigations of HMOs in milk from women delivering preterm have been limited. We present the first detailed mass spectrometric analysis of the fucosylation and sialylation in HMOs in serial specimens of milk from 15 women delivering preterm and 7 women delivering at term using nanohigh performance liquid chromatography chip/time-of-flight mass spectrometry. A mixed-effects model with Levene's test was used for the statistical analyses. We find that lacto-N-tetraose, a core HMO, is both more abundant and more highly variable in the milk of women delivering preterm. Furthermore, fucosylation in preterm milk is not as well regulated as in term milk, resulting in higher within and between mother variation in women delivering preterm vs term. Of particular clinical interest, the α1,2-linked fucosylated oligosaccharide 2'-fucosyllactose, an indicator of secretor status, is not consistently present across lactation of several mothers that delivered preterm. The immaturity of HMO production does not appear to resolve over the time of lactation and may have relevance to the susceptibility of premature infants to necrotizing enterocolitis, late onset sepsis, and related neurodevelopmental impairments. 相似文献
840.