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101.
Morinda citrifolia adventitious roots were cultured in shake flasks using Murashige and Skoog medium with different types and concentrations
of auxin and cytokinin. Root (fresh weight and dry weight) accumulation was enhanced at 5 mg l−1 indole butyric acid (IBA) and at 7 and 9 mg l−1 naphthalene acetic acid (NAA). On the other hand, 9 mg l−1 NAA decreased the anthraquinone, phenolic and flavonoid contents more severely than 9 mg l−1 IBA. When adventitious roots were treated with kinetin (0.1, 0.3 and 0.5 mg l−1) and thidiazuron (TDZ; 0.1, 0.3 and 0.5 mg l−1) in combination with 5 mg l−1 IBA, fresh weight and dry weight decreased but secondary metabolite content increased. The secondary metabolite content (including
1,1-diphenyl-2-picrylhydrazyl activity) increased more in TDZ-treated than in kinetin-treated roots. Antioxidative enzymes
such as catalase (CAT) and guaiacol peroxidase (G-POD), which play important roles in plant defense, also increased. A strong
decrease in ascorbate peroxidase activity resulted in a high accumulation of hydrogen peroxide. This indicates that adventitious
roots can grow under stress conditions with induced CAT and G-POD activities and higher accumulations of secondary metabolites.
These results suggest that 5 mg l−1 IBA supplementation is useful for growth and secondary metabolite production in adventitious roots of M. citrifolia. 相似文献
102.
Md. Abdullahil Baque Eun-Joo Hahn Kee-Yoeup Paek 《In vitro cellular & developmental biology. Plant》2010,46(1):71-80
An efficient protocol for adventitious root induction from leaf explants of Morinda citrifolia treated with different concentrations of indole-3-butyric acid (IBA) and α-naphthaleneacetic acid (NAA) was established in
relation to physiological process changes during adventitious root induction under different light sources (fluorescent, red,
blue, red + blue, and far-red). Among the different concentrations of IBA and NAA, 1.0 mg l−1 IBA was proven as the best auxin source for adventitious root induction under fluorescent light. Higher concentrations of
IBA and NAA trigger callus formation in both light and dark conditions. Maximum numbers of adventitious roots were induced
under red light (26) followed by blue light (22) and the lowest under far-red light (6). In contrast, numerous callus formations
were induced by red + blue followed by red and blue, while the highest root length (1.66 cm) with negligible callusing was
observed under fluorescent light. Catalase and guaicacol peroxidase activities were highest under red light followed by fluorescent
light and the lowest under red + blue light, but superoxide dismutase activity was not significantly influenced by different
light sources. Ascorbate peroxidase played an important role in detoxification of the harmful effects of hydrogen peroxide
(H2O2). Under fluorescent light, significantly lower accumulation of H2O2 was observed. Accumulation of H2O2 in the induced root under different light showed a positive correlation with peroxidation of lipids and was observed higher
under far-red followed by red + blue and blue light. 相似文献
103.
Arabidopsis CUP-SHAPED COTYLEDON3 regulates postembryonic shoot meristem and organ boundary formation 总被引:1,自引:0,他引:1 下载免费PDF全文
Overall shoot architecture in higher plants is highly dependent on the activity of embryonic and axillary shoot meristems, which are produced from the basal adaxial boundaries of cotyledons and leaves, respectively. In Arabidopsis thaliana, redundant functions of the CUP-SHAPED COTYLEDON genes CUC1, CUC2, and CUC3 regulate embryonic shoot meristem formation and cotyledon boundary specification. Their functional importance and relationship in postembryonic development, however, is poorly understood. Here, we performed extensive analyses of the embryonic and postembryonic functions of the three CUC genes using multiple combinations of newly isolated mutant alleles. We found significant roles of CUC2 and CUC3, but not CUC1, in axillary meristem formation and boundary specification of various postembryonic shoot organs, such as leaves, stems, and pedicels. In embryogenesis, all three genes make significant contributions, although CUC3 appears to possess, at least partially, a distinct function from that of CUC1 and CUC2. The function of CUC3 and CUC2 overlaps that of LATERAL SUPPRESSOR, which was previously shown to be required for axillary meristem formation. Our results reveal that redundant but partially distinct functions of CUC1, CUC2, and CUC3 are responsible for shoot organ boundary and meristem formation throughout the life cycle in Arabidopsis. 相似文献
104.
A multispecific monoclonal antibody G2 recognizes at least three completely different epitope sequences with high affinity 下载免费PDF全文
Md. Nuruddin Mahmud Masayuki Oda Daiki Usui Yasuo Inoshima Naotaka Ishiguro Yuji O. Kamatari 《Protein science : a publication of the Protein Society》2017,26(11):2162-2169
A monoclonal antibody (mAb) G2 possesses an unusual characteristic of reacting with at least three proteins (ATP6V1C1, SEPT3, and C6H10orf76) other than its original antigen, chicken prion protein (ChPrP). The epitopes on ChPrP and ATP6V1C1 have been identified previously. In this study, we identified the epitope in the third protein, SEPT3. Interestingly, there was no amino acid sequence similarity among the epitopes on the three proteins. These epitopes had high binding affinities to G2 (K D = ~10?7 M for monovalent binding and K D = ~10?9 M for divalent binding), as determined using a SPR biosensor. This is the first report on a three‐in‐one mAb recognizing completely different epitope sequences with high affinity. Additionally, competitive ELISA indicated that the binding sites on G2, specific for the three different epitopes, overlapped, suggesting that the antigen‐binding site may be flexible in the free form and capable of adapting to at least three different conformations to enable interactions with three different antigens. 相似文献
105.
This article attempts to evaluate men's approval of family planning in Bangladesh using the couple data set from the recent Bangladesh Demographic and Health Survey (BDHS), 1999-2000. Family planning approval is addressed both from individual and couple perspectives. Analysis of BDHS data shows that about 85% of the wives report that their husbands approve of family planning, which is lower than the wives' own approval rate (95%). Using the couple data set, husbands' characteristics were matched to the wives' responses on family planning approval. Regression analyses show that age, education, access to TV, inter-spousal communication, current use of family planning and the number of living children significantly determine family planning approval among both men as well as couples. Family planning approval was found to be much lower in Sylhet than in the other administrative divisions. Multilevel modelling analysis suggests almost negligible variation at the community level. The findings indicate the need for careful evaluation of the DHS questions in order to measure appropriately men's family planning attitudes. 相似文献
106.
Katherine E. Atkins Andrew F. Read Nicholas J. Savill Katrin G. Renz AFM Fakhrul Islam Stephen W. Walkden‐Brown Mark E. J. Woolhouse 《Evolution; international journal of organic evolution》2013,67(3):851-860
Marek’s disease virus (MDV), a commercially important disease of poultry, has become substantially more virulent over the last 60 years. This evolution was presumably a consequence of changes in virus ecology associated with the intensification of the poultry industry. Here, we assess whether vaccination or reduced host life span could have generated natural selection, which favored more virulent strains. Using previously published experimental data, we estimated viral fitness under a range of cohort durations and vaccine treatments on broiler farms. We found that viral fitness maximized at intermediate virulence, as a result of a trade‐off between virulence and transmission previously reported. Our results suggest that vaccination, acting on this trade‐off, could have led to the evolution of increased virulence. By keeping the host alive, vaccination prolongs infectious periods of virulent strains. Improvements in host genetics and nutrition, which reduced broiler life spans below 50 days, could have also increased the virulence of the circulating MDV strains because shortened cohort duration reduces the impact of host death on viral fitness. These results illustrate the dramatic impact anthropogenic change can potentially have on pathogen virulence. 相似文献
107.
Cassandra L.A. Hawco Estelle Marchal Md. Imam Uddin Alexander E.G. Baker Dale P. Corkery Graham Dellaire Alison Thompson 《Bioorganic & medicinal chemistry》2013,21(19):5995-6002
To generate the first series of prodigiosene conjugates, the tripyrrolic skeleton was appended to estrone, tamoxifen and porphyrin frameworks by way of ester linkers and various hydrocarbon chain lengths. The ability of the conjugates to inhibit various types of cancer cells was evaluated in vitro. The porphyrin conjugates did not exhibit significant activity. The estrone conjugates exhibited modest activity, for the most part. However, significantly greater growth inhibition activity against certain breast, colon, lung, leukemia, melanoma and prostate cell lines was noted. This unusual effect for this first generation model class of compound warrants further investigation and comparison to cases where estrogens are linked to prodigiosenes via connection points that do not feature in estrogen receptor binding. The 4-hydroxytamoxifen conjugates exhibit nanomolar range activity against the MCF-7 breast cancer cell line, paving the way to expand the scope and connectivity of prodigiosene–tamoxifen conjugates. 相似文献
108.
We offer a new hypothesis to explain calcium flows in skeletal muscle cells. Our model accounts for the uptake of Ca2+ from the extracellular fluid, and the release of Ca2+ from the sarcoplasmic reticulum (SR/ER) (the endoplasmic reticulum in muscle is named sarcoplasmic reticulum); this has engendered
difficulty in reviews encompassing both muscle and nonmuscle cells. Here we will typically refer to the organelle as ER, except
when specifically discussing muscle cells. The broad consideration of two major, still unexplained properties of skeletal
muscle function, namely excitation contraction coupling and capacitative calcium entry are accounted for in a unitary hypothesis.
This model allows a reinterpretation of existing data, and points to areas where new investigation may be fruitful. While
primarily aimed at explaining Ca2+ flows in skeletal muscle, we consider findings of other systems to explore the implications of this hypothesis for other
cell types. 相似文献
109.
Henar Hernando Claire Shannon-Lowe Abul B Islam Fatima Al-Shahrour Javier Rodríguez-Ubreva Virginia C Rodríguez-Cortez Biola M Javierre Cristina Mangas Agustín F Fernández Maribel Parra Henri-Jacques Delecluse Manel Esteller Eduardo López-Granados Mario F Fraga Nuria López-Bigas Esteban Ballestar 《Genome biology》2013,14(1):R3
110.
Faiqah Ramli Mawardi Rahmani Nur Kartinee Kassim Najihah Mohd Hashim Mohd Aspollah Sukari Abdah Md Akim Rusea Go 《Phytochemistry letters》2013,6(4):582-585
Two new diprenylated dihydrochalcones, elastichalcone A 1 and elastichalcone B 2 and three known compounds were isolated from the leaves of Artocarpus elasticus. Their structures were determined by various spectroscopic techniques (UV, IR, MS, 1D-NMR and 2D-NMR). Elastichalcone B 2 and a known compound exhibited good free radical scavenging activity with IC50 values of 11.30 and 11.89 μg/ml, respectively. 相似文献