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991.
Exploiting cell cycle inhibitor genes of the KRP family to control root‐knot nematode induced feeding sites in plants
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José Dijair Antonino de Souza Júnior Cristina Martin‐Jimenez Lieven De Veylder Julie Cazareth Gilbert Engler Maria Fatima Grossi‐de‐Sa Janice de Almeida Engler 《Plant, cell & environment》2017,40(7):1174-1188
Cell cycle control in galls provoked by root‐knot nematodes involves the activity of inhibitor genes like the Arabidopsis ICK/KRP members. Ectopic KRP1, KRP2 and KRP4 expression resulted in decreased gall size by inhibiting mitotic activity, whereas KRP6 induces mitosis in galls. Herein, we investigate the role of KRP3, KRP5 and KRP7 during gall development and compared their role with previously studied members of this class of cell cycle inhibitors. Overexpression of KRP3 and KRP7 culminated in undersized giant cells, with KRP3OE galls presenting peculiar elongated giant cells. Nuclei in KRP3OE and KRP5OE lines presented a convoluted and apparently connected phenotype. This appearance may be associated with the punctuated protein nuclear localization driven by specific common motifs. As well, ectopic expression of KRP3OE and KRP5OE affected nematode development and offspring. Decreased mitotic activity in galls of KRP3OE and KRP7OE lines led to a reduced gall size which presented distinct shapes – from more elongated like in the KRP3OE line to small rounded like in the KRP7OE line. Results presented strongly support the idea that induced expression of cell cycle inhibitors such as KRP3 and KRP7 in galls can be envisaged as a conceivable strategy for nematode feeding site control in crop species attacked by phytopathogenic nematodes. 相似文献
992.
993.
Narel Y. Paniagua Zambrana Rainer W. Bussmann Robbie E. Hart Araceli L. Moya Huanca Gere Ortiz Soria Milton Ortiz Vaca David Ortiz Álvarez Jorge Soria Morán María Soria Morán Saúl Chávez Bertha Chávez Moreno Gualberto Chávez Moreno Oscar Roca Erlin Siripi 《Journal of ethnobiology and ethnomedicine》2017,13(1):57
Background
The Chácobo are a Panoan speaking tribe of about 1000 members (300+ adults) in Beni, Bolivia. Originally nomadic, the Chácabo were relocated to their current main location in the 1960s. Researchers have visited the Chácabo since 1911. A first more detailed anthropological report exists from the late 1960s, and ecological–ethnobotanical studies were conducted in the 1980s and 1990s. The presented work represents a complete ethnobotanical inventory of the entire adult Chácobo population, with interviews and plant collection conducted directly by Chácobo counterparts.Methods
Based on previous reports and our preliminary studies, we hypothesized that twenty-first century Chácobo plant use centered on income generation, and that traditional plant use related to household utensils, medicine and traditional crop varieties had almost disappeared. To test this hypothesis, we started the “Chácobo Ethnobotany Project,” training 10 indigenous Chácobo participants in ethnobotanical interview and plant collection techniques, in order to more fully document Chácobo knowledge and avoid the influence of foreign interviewers.Results
Our study found 331 useful plant species in 241genera of 95 plant families, with leaves, roots and bark being the most commonly used plant parts The comprehensive documentation that these methods enabled completely nullified our initial hypothesis of knowledge loss. Traditional crop varieties are still widely grown and traditional knowledge is alive. Moreover, it is being actively recuperated in certain domains by the younger generation. Most Chácobo know, and can name, traditional utensils and tools, although only the older generation has still the skills to manufacture them. While many Chácobo still know the names and uses of medicinal species, the younger generation is however often unsure how to identify them.Conclusions
In this paper we illustrate the complexity of perspectives on knowledge at different ages, and the persistence of knowledge over almost a century. We found that traditional knowledge was only partially affected by the processes of exposure to a market economy, and that different knowledge domains experienced different trends as a result of these changes. Overall knowledge was widely distributed, and we did not observe a directional knowledge loss.We stress the importance to not directly conclude processes of knowledge loss, cultural erosion or acculturation when comparing the knowledge of different age groups.994.
The effect of a static magnetic field on human erythrocytes at different hemoglobin states (normal, oxidized and reduced hemoglobin) was investigated. Three different blood samples, normal, iron deficiency anemic and beta thalassemia minor, were studied. Measurements of the magnetization curves of the erythrocytes for all blood samples in all states showed diamagnetic behavior; however, oxidation was found to enhance this behavior. These measurements have also shown that the normal and iron deficiency samples in the reduced states exhibit a less diamagnetic response in comparison with the normal state. This result indicates that the reduction process gave rise to a paramagnetic component of the magnetization. Analysis of the measured paramagnetic behavior, using a Brillouin function, gave an effective magnetic moment of 8 muB per reduced hemoglobin molecule for both normal and anemic samples. This result shows that both anemic and normal blood have similar magnetic behavior and the only difference is the number of hemoglobin molecules per erythrocyte. For the beta thalassemia minor blood sample, magnetic measurements showed that both the normal and reduced states have almost the same diamagnetic behavior. However, this diamagnetic response is less than that for the normal state of the iron deficiency anemic sample. This result may indicate a low oxygen intake for the blood in the normal state for the beta thalassemia minor blood. All magnetic measurements were made using a vibrating sample magnetometer using field steps of 0.001 T from 1 T to -1 T. 相似文献
995.
996.
对在大冷山自然保护区药用苔藓植物进行野外调查、样本采集,形态分类和鉴定,系统分析了其分布特征和药效功能.结果表明,该区域共有药用苔藓植物14科16属17种,其中包括3种苔类,14种藓类植物.17种药用苔藓植物中具有治疗烫伤或烧伤等功效的有4种,具有清热解毒治疗炎症作用的有7种,具有止血功效的有4种,对淋巴细胞白血病和神... 相似文献
997.
Protection by protein A of apoptotic cell death caused by anti-AIDS drug zidovudine. 总被引:1,自引:0,他引:1
A K Ghosh S Jana T Das G Sa N Mandal P K Ray 《Biochemical and biophysical research communications》1999,264(2):601-604
Zidovudine, the anti-AIDS drug, caused inhibition of mitogen-induced proliferation and perturbation of cell-cycle progression of cultured bone marrow cells of mice. There was significant hypoploidy observed in flow cytometric analysis of AZT-treated bone marrow cells. In apo-direct analysis, cells showed apoptosis in G0/G1 phase. In DNA gel analysis, characteristic laddering of apoptosis was observed in AZT-treated bone marrow cells. We demonstrated that, when the animals were pretreated with protein A (PA) of Staphylococcus aureus, the apoptotic changes could be prevented in bone marrow cells of AZT-treated animals. There is a significant (p < 0.05) increase in proliferation of bone marrow cells subjected to mitogen treatment in PA+AZT-treated animals, compared to only AZT-treated animals. However, cell-cycle phase distribution was not hampered and no laddering in DNA gel analysis was also observed in this group. In apo-direct analysis, PA treatment showed significant (p < 0.001) inhibition of AZT-induced apoptosis. These observations indicate that by using a suitable agent such as protein A the toxic side effects of AZT could be minimized. 相似文献
998.
防御素基因工程研究进展 总被引:10,自引:0,他引:10
防御素是一类在生物界广泛存在的、富含半胱氨酸、具有微生物和一些恶性细胞抗性的小分子短肽。它具有抗性谱广,作用机理特殊等优点;因此可以用来研制新型的抗生素类药,并在动植物抗病基域工程上发挥重要作用。概述了防御素在基因工程方面的研究进展,并对其应用前景作了展望。 相似文献
999.
Background
HIV-1 has evolved ways to exploit DCs, thereby facilitating viral dissemination and allowing evasion of antiviral immunity. Recently, the fate of DCs has been found to be extremely dependent on the interaction with autologous NK cells, but the mechanisms by which NK-DC interaction controls viral infections remain unclear. Here, we investigate the impact of NK-DC cross-talk on maturation and functions of HIV-infected immature DCs.Methodology/Principal Findings
Immature DCs were derived from primary monocytes, cultured in the presence of IL-4 and GM-CSF. In some experiments, DCs were infected with R5-HIV-1BaL or X4-HIV-1NDK, and viral replication, proviral HIV-DNA and the frequency of infected DCs were measured. Autologous NK cells were sorted and either kept unstimulated in the presence of suboptimal concentration of IL-2, or activated by a combination of PHA and IL-2. The impact of 24 h NK-DC cross-talk on the fate of HIV-1-infected DCs was analyzed. We report that activated NK cells were required for the induction of maturation of DCs, whether uninfected or HIV-1-infected, and this process involved HMGB1. However, the cross-talk between HIV-1-infected DCs and activated NK cells was functionally defective, as demonstrated by the strong impairment of DCs to induce Th1 polarization of naïve CD4 T cells. This was associated with the defective production of IL-12 and IL-18 by infected DCs. Moreover, the crosstalk between activated NK cells and HIV-infected DCs resulted in a dramatic increase in viral replication and proviral DNA expression in DCs. HMGB1, produced both by NK cells and DCs, was found to play a pivotal role in this process, and inhibition of HMGB1 activity by glycyrrhizin, known to bind specifically to HMGB1, or blocking anti-HMGB1 antibodies, abrogated NK-dependent HIV-1 replication in DCs.Conclusion
These observations provide evidence for the crucial role of NK-DC cross-talk in promoting viral dissemination, and challenge the question of the in vivo involvement of HMGB1 in the triggering of HIV-1 replication and replenishment of viral reservoirs in AIDS. 相似文献1000.
Malkov SN Zivković MV Beljanski MV Hall MB Zarić SD 《Journal of molecular modeling》2008,14(8):769-775
The correlation between the primary and secondary structures of proteins was analysed using a large data set from the Protein
Data Bank. Clear preferences of amino acids towards certain secondary structures classify amino acids into four groups: α-helix
preferrers, strand preferrers, turn and bend preferrers, and His and Cys (the latter two amino acids show no clear preference
for any secondary structure). Amino acids in the same group have similar structural characteristics at their Cβ and Cγ atoms
that predicts their preference for a particular secondary structure. All α-helix preferrers have neither polar heteroatoms
on Cβ and Cγ atoms, nor branching or aromatic group on the Cβ atom. All strand preferrers have aromatic groups or branching
groups on the Cβ atom. All turn and bend preferrers have a polar heteroatom on the Cβ or Cγ atoms or do not have a Cβ atom
at all. These new rules could be helpful in making predictions about non-natural amino acids.
相似文献
Snežana D. ZarićEmail: |