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41.
Yali Xu Amrita Yasin Thomas Wucherpfennig C. Perry Chou 《World journal of microbiology & biotechnology》2008,24(12):2827-2835
Functional expression of heterologous Pseudozyma antarctica lipase B (PalB) in the periplasm of Escherichia coli was explored using four fusion tags, i.e. DsbC, DsbA, maltose-binding protein (MBP), and FLAG in the sequence of increasing
expression efficacy. Amongst these fusion tags, FLAG and MBP appear to be the most effective ones in terms of boosting enzyme
activity and enhancing solubility of PalB, respectively. Overexpression of these PalB fusions often resulted in concomitant
formation of insoluble inclusion bodies. Coexpression of a selection of periplasmic folding factors, including DegP (and its
mutant variant of DegPS210A), FkpA, DsbA, DsbC, and a cocktail of SurA, FkpA, DsbA, and DsbC, could improve the expression performance. Coexpression
of DsbA appeared to be the most effective in reducing the formation of inclusion bodies for all the four PalB fusions, implying
that functional expression of PalB could be limited by initial bridging of disulfide bonds. Culture performance was optimized
by overexpressing FLAG-PalB with DsbA coexpression, resulting in a high volumetric PalB activity of 360 U/L. 相似文献
42.
Iovinella Manuela Eren Ayla Pinto Gabriele Pollio Antonino Davis Seth J. Cennamo Paola Ciniglia Claudia 《Extremophiles : life under extreme conditions》2018,22(5):713-723
Extremophiles - Cyanidiophytina are a group of polyextremophilic red algae with a worldwide, but discontinuous colonization. They are restricted to widely dispersed hot springs, geothermal... 相似文献
43.
The plant family Boraginaceae is known to produce a set of unusual fatty acids in the seed oils. In this study, the fatty acid, tocopherol, tocotrienol and plasto-chromanol-8 contents of some Onosma species ( Onosma sericeum, O. armeniacum and O. polioxanthum ) all belonging to sect. Onosma, Anchusa leptophylla subsp. leptophylla, Alkanna froedini and Paracaryum stenophyllum were determined. Some of the studied species are endemic for Turkey. While oleic, linoleic and alpha linolenic acid are the highest as usual fatty acids, gamma linolenic and stearidonic acids are more variable unusual fatty acids in studied genera patterns and the relative concentrations some of these fatty acids and partly also the tocochromanols in Boraginaceae seed oils are suggested to have chemotaxonomic value in this family. In particular, the presence or absence of chain elongation to erucic acid (22:1) and the presence or absence of Δ6-methylene-interrupted polyenoic acids such as γ-linolenic and stearidonic acid are determined and marked as indicators of taxonomic relationship. 相似文献
44.
45.
In the present study, the relationship between the nutritional status of leaves and the development of symptoms of cotton leaf curl virus (CLCuV) in two cotton (Gossypium hirsutum L.) cultivars (i.e. CIM-240 and S-12) was investigated. The incidence of disease attack was found to be 100% in the S-12 cultivar and 16% in the CIM-240 cultivar. Geminivirus particles in infected leaves were confirmed by transmission electron microscope examination of highly specific geminivirus coat protein antisera-treated cell sap. The CLCuV impaired the accumulation of different nutrients in both cultivars. A marked decrease in the accumulation of Ca2+ and K+ was observed in infected leaves. However, the disease had no effect on leaf concentrations of Na+, N, and P. It was observed that the curling of leaf margins in CLCuV-infected plants was associated with the leaf Ca2+ content; leaf curling was severe in plants with a significant reduction in Ca2+ content.Moreover, leaf K+ content was found to be associated with resistance/susceptibility to CLCuV infection. 相似文献
46.
47.
Narejo Ghulam Abbas Mirbahar Ameer Ahmed Yasin Sanaullah Sirohi Muzafar Hussain Saeed Rafat 《Journal of Plant Growth Regulation》2023,42(3):1592-1603
Journal of Plant Growth Regulation - Cotton (Gossypium hirsutum L.) is an important cash crop; its germination is very susceptible to salinity. Saline conditions result in a severe decline in yield... 相似文献
48.
Yasin Eren Sevim Feyza Erdoğmuş Dilek Akyıl Arzu Özkara Muhsin Konuk Esra Sağlam 《Cytotechnology》2015,67(6):1023-1030
Dioxacarb (Elecron, Famid) is a phenyl methylcarbamate insecticide and in vitro cytotoxic and genotoxic effects of this pesticide on human peripheral blood lymphocytes and Allium root meristematic cells were investigated by chromosomal aberrations (CAs) and Allium test. Human lymphocytes were treated with 62.5, 125, 250 and 500 ppm doses of dioxacarb for CAs. CA/cell, abnormal cell % and mitotic index % (MI %) data were obtained from these concentrations in 24 and 48 h treatment periods. Dioxacarb did not increase the CA/cell frequency significantly, so this insecticide was not identified as genotoxic. But it was found cytotoxic especially at 250 and 500 ppm concentrations because of the reduced the MI % and increased the abnormal cell %. In Allium test, 25 ppm (EC50/2), 50 ppm (EC50) and 100 ppm (EC50 × 2) concentrations were used for root growth inhibition (EC50 determination) and Allium mitotic index (MI) determination tests. The used concentrations of dioxacarb induced dose-dependent inhibition of MI and root growth on root meristems. Mitotic inhibition of dioxacarb was found significantly higher than for the positive control. These Allium results indicated the high cytotoxicity of dioxacarb. The present study is the first research on cytotoxicity and genotoxicity of dioxacarb by human lymphocyte CAs and Allium test. 相似文献
49.
An experiment was conducted to determine the effect of water stress on nutritional changes in tolerant (DS-4 and Chakwal-86)
and susceptible (DS-17 and Pavon) genotypes in lysimeters. The stress was imposed at different growth stages (pre-anthesis,
post-anthesis, terminal drought). The biomass (dry weight) and Ca, Mg and P concentration decreased with water stress in all
the wheat genotypes. However, the tolerant genotypes had less reduction than susceptible at all the treatments. Potassium
increased in all wheat genotypes due to water stress and was higher in tolerant than susceptible genotypes. Sodium content
was not affected by water stress. 相似文献
50.
This study aimed to examine the effects of CPB on salusin-α, salusin-β and apelin-36 bioactive peptides in people who are planned to undergo coronary artery bypass graft (CABG) operation due to coronary artery disease and to explore whether these peptides are produced in human aortic, saphenous and arterial tissues. The study included age and BMI matched 15 patients who underwent CABG operation by CPB. In order to determine salusin-α, salusin-β and apelin-36 levels, venous blood samples were collected before induction of anesthesia (T1), before CPB (T2), 5min before the removal of cross-clamp (T3), 5min after the removal of cross-clamp (T4), upon arrival in the intensive care (T5), at postoperative 24th hour (T6) and 72nd hour (T7). Salusin and apelin expressions of the tissues were shown by immunohistochemical method. Peptide amounts of sera and tissues were measured using ELISA. Salusins production by vessels occurs in fibroblast cells of the media in the aorta and smooth muscle cells of the media in the LIMA and saphena. Apelin is produced by endothelial cells of the intima and fibroblast cells of the media in the aorta and by smooth muscle cells of the media in the LIMA and saphena. Changes in the levels of salusin-β and apelin-36 were significant during CPB. Salusin-α, salusin-β and apelin-36 are locally synthesized in the arteries and veins. Salusins and apelin-36 might be important markers in the CPB, and also that salusin-β was more specific in comparison to salusin-α. 相似文献