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991.
In a field study conducted around Lake Manzala (Egypt) during 1995–1996, the distribution of the floating-leafed lotus (Nymphaea
lotus L.) in irrigation canals and ricefields was analyzed by classification and ordination methods. Environmental factors
associated with its abundance and distribution were evaluated. A data set of 30 stands of lotus and nine environmental variables
was analyzed by Canonical Correspondence Analysis (CCA) ordination relating environmental factors to the occurrence of the
weed. Ordination analysis detected a strong association between soil organic matter and fine sediment (silt + clay) in the
distribution of lotus. Water variables were less important. The density of lotus averaged 3.3±0.49 plants m−2 in the irrigation
canals and 6.6±1.4 plants m−2 in the ricefields. The phytomass of lotus ranged from 877 g m−2 in the pure stands to 226 g
m−2 in ricefield habitats. The highest proportion of lotus phytomass was allocated to leaf blade, with values reaching 40%
of total phytomass in the infested ricefields. Allocation proportions to other plant organs varied between natural and ricefield
habitats. Lotus plants allocated more dry matter to vegetative reproduction than to sexual reproduction. The ratio of vegetative
to sexual reproduction ranged from 3.48 in the pure stands to 9.63 in infested ricefields. Populations of lotus showed wider
variation in leaf area classes in pure stands than in rice stands. Presence of lotus as a weed in ricefields significantly
reduced the growth and grain yield of the crop, indicating the risk of its spreading as an invasive weed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
Mahmoud A. Omar Mohamed A. Abdel Hamid Hany A. Batakoushy Hytham M. Ahmed 《Luminescence》2020,35(2):260-265
A highly accurate, simple and sensitive spectrofluorimetric analytical method for dapagliflozin (DGF) quantitation was developed. The proposed method was successively applied to DGF analysis in both its pure and pharmaceutical dosage forms. This method was developed to investigate DGF stability in its degradation products, as laid out in International Council for Harmonisation (ICH) rules. Kinetics of alkaline degradation of DGF was also calculated. The half‐life time (t1/2) of the reaction was 75.32 min. An alkaline degradation pathway was described. The present study involved measurement of the second‐derivative synchronous fluorescence intensity of DGF at Δλ = 30 nm. Peak amplitude was measured at 322 nm. Linear range of the calibration curve was 0.1–1.0 μg ml?1. Lower detection and quantitation limits were 0.023 and 0.071 μg ml?1, respectively, and indicated good sensitivity of the proposed method. Mean per cent recovery was 99.78 ± 1.78%. The proposed analytical approach was successfully applied to DGF in the quality control laboratory and would be suitable as a stability‐indicating assay. 相似文献
993.
Transduction efficacy and retrograde movement of a lentiviral vector pseudotyped by modified rabies glycoprotein throughout the trisynaptic circuit of the rat hippocampus 下载免费PDF全文
994.
Sanaz Zardari Farshid Ghaderi-Far Hamid R. Sadeghipour Ebrahim Zeinali Elias Soltani Carol C. Baskin 《Plant Species Biology》2019,34(3):85-94
We tested the hypothesis that seeds of the monocarpic perennial Ferula gummosa from the Mediterranean area and central Asia have deep complex morphophysiological dormancy. We determined the water permeability of seeds, embryo morphology, temperature requirements for embryo growth and seed germination and responses of seeds to warm and cold stratification and to different concentrations of GA3. The embryo has differentiated organs, but it is small (underdeveloped) and must grow inside the seed, reaching a critical embryo length, seed length ratio of 0.65–0.7, before the seed can germinate. Seeds required 9 weeks of cold stratification at <10°C for embryo growth, dormancy break and germination to occur. Thus, seeds have morphophysiological dormancy (MPD). Furthermore, GA3 improved the germination percentage and rate at 5°C and promoted 20 and 5% germination of seeds incubated at 15 and 20°C, respectively. Thus, about 20% of the seeds had intermediate complex MPD. For the other seeds in the seed lot, cold stratification (5°C) was the only requirement for dormancy break and germination and GA3 could not substitute for cold stratification. Thus, about 80% of the seeds had deep complex MPD. 相似文献
995.
Hamid Reza Mirzaei Hamed Mirzaei Afshin Namdar Majid Rahmati Brian G. Till Jamshid Hadjati 《Journal of cellular physiology》2019,234(5):5827-5841
The adoptive transfer of genetically engineered T cells modified to express a chimeric antigen receptor (CAR) has shown remarkable activity and induces long-term remissions in patients with advanced hematologic malignancies. To date, little is known about predictive indicators of therapeutic efficacy or serious toxicity after CAR T-cell therapy in clinical practice. Biomarkers are not only potentially able to inform physicians and researchers of immunotherapy targets in particular but could also be used to monitor the effectiveness of treatments and to predict incidence of side effects in some circumstances. Identification of new biomarkers can therefore not only contribute to the development of new therapeutic and prognostic strategies for CAR T-cell therapy for cancer but also help to generate improved clinical practices for early recognition and minimization of adverse effects while preserving the antitumor activity of the CAR T cells. Herein, we will consider a variety of predictive and therapeutic biomarkers in CAR T-cell therapy and the state of current understanding of their clinical utility. The incorporation of biomarker studies in CAR T-cell clinical trials and practice will help to realize the potential clinical benefit of biomarker-guided therapy. 相似文献
996.
Wynn J.P. Hamid A.A. Midgley M. Ratledge C. 《World journal of microbiology & biotechnology》1997,14(1):145-147
World Journal of Microbiology and Biotechnology - Ten filamentous fungi, belonging to five different genera of both higher and lower fungi, including oleaginous fungi and fungi known to produce... 相似文献
997.
Storr SJ Royle L Chapman CJ Hamid UM Robertson JF Murray A Dwek RA Rudd PM 《Glycobiology》2008,18(6):456-462
MUC1 is a high molecular weight glycoprotein that is overexpressed in breast cancer. Aberrant O-linked glycosylation of MUC1 in cancer has been implicated in disease progression. We investigated the O-linked glycosylation of MUC1 purified from the serum of an advanced breast cancer patient. O-Glycans were released by hydrazinolysis and analyzed by liquid chromatography-electrospray ionization-mass spectrometry and by high performance liquid chromatography coupled with sequential exoglycosidase digestions. Core 1 type glycans (83%) dominated the profile which also confirmed high levels of sialylation: 80% of the glycans were mono-, di- or trisialylated. Core 2 type structures contributed approximately 17% of the assigned glycans and the oncofoetal Thomsen-Friedenreich (TF) antigen (Galbeta1-3GalNAc) accounted for 14% of the total glycans. Interestingly, two core 1 type glycans were identified that had sialic acid alpha2-8 linked to sialylated core 1 type structures (9% of the total glycan pool). This is the first O-glycan analysis of MUC1 from the serum of a breast cancer patient; the results suggest that amongst the cell lines commonly used to express recombinant MUC1 the T47D cell line processes glycans that are most similar to patient-derived material. 相似文献
998.
A high positive correlation was found between extractable Ni and Co contents and microbial activity of 40 ultramafic soil samples from New Caledonia, suggesting a possible role of microorganisms in the release of these two metals. A saprolite (ultramafic subsoil) and a hypermagnesian brown soil were incubated 9 months in different conditions. Ni and Co release, measured by their extractability, occurred without reduction of soil pH but did not occur when the native microflora was eliminated by heat treatment. However, when autoclaved soil was re-inoculated with a pinch of the same nonheated soil, the release of metals was recorded. The concentrations of extractable Ni and Co were much higher in soils amended with organic compounds in which microbial activity was enhanced, but only if the soil was not heat treated. The presence of Grevillea exul, a metal-tolerant plant, stimulated the metal release process, but the stimulation was less effective than it was in the compost-amended soil without plant. The influence of the plant in extractable Ni and Co contents in this amended soil was not significant. The release of the two metals therefore seemed to be induced by the activity of specialized organotrophic microorganisms. 相似文献
999.
In vitro and in vivo characterization of the minimal promoter region of the human thiamin transporter SLC19A2 总被引:2,自引:0,他引:2
The molecular mechanisms involved in the regulation of thiamin transport in mammalian cells are poorly understood. Previous studies established that a human thiamin transporter, SLC19A2, plays a role in thiamin uptake in human tissues. We cloned the 5' regulatory region of the SLC19A2 gene, identified the minimal promoter required for basal activity, and located multiple putative cis elements. To further characterize the SLC19A2 promoter, we investigated, in the present study, the role of the putative cis elements in regulating the activity of the SLC19A2 promoter in vitro and confirmed the activity of the SLC19A2 promoter in vivo. In vitro studies demonstrated that mutation of specific cis elements in the SLC19A2 minimal promoter [Gut-enriched Krupple-like factor (GKLF), nuclear factor-1 (NF-1), and stimulating protein-1 (SP-1)] led to a decrease in activity. Using electrophoretic mobility shift assays, four specific DNA/protein complexes were identified. The interacting factors were determined by oligonucleotide competition and antibody supershift analysis and shown to be GKLF, NF-1, and SP-1. Cotransfection studies of the SLC19A2 promoter with an SP-1 containing vector in Drosophila SL2 cells further confirmed a role for SP-1 in regulating SLC19A2 promoter activity. In vivo studies using transgenic mice established the functionality of the full-length and minimal SLC19A2 promoters. Furthermore, our studies revealed that the pattern of expression of the SLC19A2 promoter-Luciferase constructs in transgenic mice was similar to the reported SLC19A2 RNA expression pattern in native human tissues. The results demonstrate the importance of GKLF, NF-1, and SP-1 in regulating the activity of the SLC19A2 promoter and provide direct in vivo confirmation of promoter activity. promoter analysis in vitro and in vivo; thiamin transport; transgenic mice 相似文献
1000.