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111.
JOSÉ ARTURO ALCÁNTARA‐RODRÍGUEZ JORGE CIROS‐PÉREZ ELIZABETH ORTEGA‐MAYAGOITIA CARMEN R. SERRANIA‐SOTO ELÍAS PIEDRA‐IBARRA 《Freshwater Biology》2012,57(4):728-740
1. Salinity is a strong selective force for many aquatic organisms, affecting both ecological and evolutionary processes. Most of our knowledge on the effects of salinity on rotifers in the Brachionus plicatilis species complex is based mainly on populations from waterbodies that experience broad environmental changes both seasonally and annually. We tested the hypothesis that, despite the supposedly high potential for gene flow among rotifers inhabiting neighbouring environments, constant salinity has promoted local adaptation, genetic population divergence and even cryptic speciation in B. plicatilis complex populations from three deep maar lakes of distinct salinities [1.1, 6.5 and 9.0 g L?1 total dissolved solids (TDS)] in Central Mexico. 2. To look for local adaptation, we performed common garden experiments to test the effect of different salinities on population density and intrinsic growth rate (r). Then, we evaluated the genetic divergence by sequencing the cytochrome c oxidase subunit I (COI) gene and performed reproductive trials to assess the potential gene flow among the three populations and with other closely related B. plicatilis complex species. 3. We confirmed that the rotifer populations have phenotypic plasticity in tolerance of salinity, but only rotifers from the least saline lake are adapted to low salinity. Among the populations, sequence divergence at COI was very low (just a single haplotype was found), suggesting a persistent founder effect from a relatively recent single colonisation event and a subsequent dispersal from one lake to the others, and a very restricted immigration rate. In the phylogenetic analysis, rotifers from this area of Mexico clustered in the same clade with the middle‐sized species Brachionus ibericus and B. sp. ‘Almenara’. Mexican rotifers showed successful recognition, copulation and formation of hybrids among them, but interpopulation breeding with the Spanish B. ibericus and B. sp. ‘Almenara’ was unsuccessful. 4. We conclude that the B. plicatilis complex populations from these three lakes belong to a new biological species not yet described (presently named B. sp. ‘Mexico’). To our knowledge, this is the first report of local adaptation of a natural B. plicatilis complex population living in freshwater conditions (1.1 g L?1 TDS). 相似文献
112.
Abstract Partial rootzone drying (PRD) and regulated deficit irrigation (RDI) are water saving irrigation systems that have been developed to increase water use efficiency (WUE) without significant yield reduction. To examine whether tomato responded differently to RDI and PRD, we compared the changes in antioxidative defenses in tomato plants using a split-root system. Tomato plants were grown for 21 days under controlled conditions with their roots separated equally between two soil compartments. Three irrigation treatments were imposed: Control, receiving an amount of water equivalent to 100% of plant transpiration; PRD in which one compartment was watered with 50% of the amount of water supplied to the controls, allowing one-half of the root system to be exposed to dry soil, and switching irrigation between sides weekly; RDI in which 50% of the amount of water given to the controls was supplied, half to each side of the root system. Relative water content (RWC), midday leaf Ψ and chlorophyll content decreased largely in RDI-treated plants, whereas the PRD plants exhibited relatively higher Ψ and RWC values. An enhanced level of lipid peroxidation in both roots and leaves indicated that PRD and RDI caused oxidative stress in tomato plants. In leaves, superoxide dismutase (SOD), soluble peroxidase (POX) and polyphenol oxidase (PPO) activities showed an increase in the early phase of water deficit, and then decreased in the remaining phase of the drying cycle. However, the increase was more pronounced under RDI. Catalase (CAT) activity declined continuously from the onset of PRD and RDI treatments to below the control level, and the reduction was less under PRD than RDI. POX cell-wall associated activities exceeded the control level by 450% and 230%, respectively, under RDI and PRD. At the root level, while CAT activity also decreased under both PRD and RDI, the activities of SOD, POX and PPO significantly increased and their activities showed an alternating increase/decrease paralleling the alternating irrigation in PRD-treated roots. As a result of the difference in POX and PPO activities between the two water treatments applied, PRD-treated plants accumulated more soluble and cell-wall bound phenolic compounds. 相似文献
113.
114.
Li C. Xue Rafael A. Jordan EL‐Manzalawy Yasser Drena Dobbs Vasant Honavar 《Proteins》2014,82(2):250-267
Selecting near‐native conformations from the immense number of conformations generated by docking programs remains a major challenge in molecular docking. We introduce DockRank, a novel approach to scoring docked conformations based on the degree to which the interface residues of the docked conformation match a set of predicted interface residues. DockRank uses interface residues predicted by partner‐specific sequence homology‐based protein–protein interface predictor (PS‐HomPPI), which predicts the interface residues of a query protein with a specific interaction partner. We compared the performance of DockRank with several state‐of‐the‐art docking scoring functions using Success Rate (the percentage of cases that have at least one near‐native conformation among the top m conformations) and Hit Rate (the percentage of near‐native conformations that are included among the top m conformations). In cases where it is possible to obtain partner‐specific (PS) interface predictions from PS‐HomPPI, DockRank consistently outperforms both (i) ZRank and IRAD, two state‐of‐the‐art energy‐based scoring functions (improving Success Rate by up to 4‐fold); and (ii) Variants of DockRank that use predicted interface residues obtained from several protein interface predictors that do not take into account the binding partner in making interface predictions (improving success rate by up to 39‐fold). The latter result underscores the importance of using partner‐specific interface residues in scoring docked conformations. We show that DockRank, when used to re‐rank the conformations returned by ClusPro, improves upon the original ClusPro rankings in terms of both Success Rate and Hit Rate. DockRank is available as a server at http://einstein.cs.iastate.edu/DockRank/ . Proteins 2014; 82:250–267. © 2013 Wiley Periodicals, Inc. 相似文献
115.
Thymol and Carvacrol Prevent Cisplatin‐Induced Nephrotoxicity by Abrogation of Oxidative Stress,Inflammation, and Apoptosis in Rats 下载免费PDF全文
El‐Sayed EM Abd‐Allah AR Mansour AM EL‐Arabey AA 《Journal of biochemical and molecular toxicology》2015,29(4):165-172
The aim of the present study is to assess the possible protective effects of thymol and carvacrol against cisplatin (CP)‐induced nephrotoxicity. A single dose of CP {6 mg/kg, intraperitoneally (i.p.)} injected to male rats revealed significant increases in serum urea, creatinine, and tumor necrosis factor alpha levels. It also increased kidney contents of malondialdehyde and caspase‐3 activity with significant reduction in serum albumin, kidney content of reduced glutathione as well as catalase, and superoxide dismutase activity as compared to that of the control group. In contrast, administration of thymol {20 mg/kg, orally (p.o.)} and/or carvacrol (15 mg/kg, p.o.) for 14 days before CP injection and for 7 days after CP administration restored the kidney function and examined oxidative stress parameters. In conclusion, thymol was more effective nephroprotective than carvacrol. Moreover, a combination of thymol and carvacrol had a synergistic nephroprotective effect that might be attributed to antioxidant, anti‐inflammatory, and antiapoptotic activities. 相似文献
116.
Md. Parvez Anwar Md. Ariful Islam Khalid A. K. M. Mominul Islam Sabina Yeasmin Sharif Ahmed Adel Hadifa Ismail A. Ismail Akbar Hossain Ayman EL Sabagh 《Phyton》2021,90(5):1491-1506
Seed priming has proved to be an effective pre-germination seed invigoration technique for different crops to
improve seed and seedling performance under different abiotic stresses. In Bangladesh, winter rice is very often
exposed to cold waves just after sowing in the nursery bed resulting in poor seed germination and seedling emergence, yellowish and thin seedlings production, and a very low survival rate. Seed priming may mitigate the cold
stress during seed germination and seedling emergence and helps in the quality seedling production of winter rice.
To evaluate the efficacy of different seed priming techniques in increasing seedling emergence, growth, vigor and
survivability of winter rice cultivars under cold stress, a pot experiment was conducted at the Department of Agronomy, Bangladesh Agricultural University during December 2018 to January 2019. The experiment comprised
two factors, (A) Winter rice variety namely, i) BRRI dhan29 and ii) BRRI dhan36; (B) Seed priming agent namely
i) Control (no priming), ii) 20000 ppm NaCl, iii) 30000 ppm NaCl, iv) 20000 ppm KCl, v) 30000 ppm KCl, vi)
20000 ppm CaCl2, vii) 30000 ppm CaCl2, viii) 50 ppm CuSO4, ix) 75 ppm CuSO4, x) 10000 ppm ZnSO4, xi)
15000 ppm ZnSO4, xii) 2 ppm Na2MoO4, xiii) 3 ppm Na2MoO4, xiv) 100 ppm PEG (Polyethylene glycol
4000) and xv) 150 ppm PEG. Seeds were sown on two different dates viz., 1st December and 1st January so that
seedlings are exposed to cold stress at different stages. The experiment was laid out in a completely randomized
design (CRD) with three replications. Results indicated that (in most of the cases) seed priming has a positive
impact on seedling emergence rate (%), root length, shoot length, root shoot ratio, root dry weight, shoot dry
weight, seedling dry weight and survival rate (%). Among the priming agents, KCl and CaCl2 performed best;
while priming with NaCl and PEG showed no advantages over no priming for both the sowing dates. In general,
BRRI dhan36 performed better than BRRI dhan29 in terms of seedling growth because of its higher tolerance to
cold stress. But, both the varieties performed similarly in terms of emergence rate and survival rate. Thus, priming
is an effective tool to increase seed germination, better seedling growth, and higher seedling survivability of winter
rice under cold stress, and KCl (20000 ppm) or CaCl2 (20000 ppm) can be considered as a viable priming agent. 相似文献
117.
Hocine Thinhinane Blaise Sebastien Hachet Cathy Guillot Alexandre Sartelet Herve Maurice Pascal Bennasroune Amar Martiny Laurent Duca Laurent Romier-Crouzet Beatrice EL Btaouri Hassan 《Journal of physiology and biochemistry》2020,76(3):457-467
Journal of Physiology and Biochemistry - Elastin, the major protein of the extracellular matrix, is specially found in cardiovascular tissues and contributing to 30–50% of the dry weight of... 相似文献
118.
Mahmuda Binte Monsur Nasrin Akter Ivy M. Moynul Haque Mirza Hasanuzzaman Ayman EL Sabagh Md. Motiar Rohman 《Phyton》2020,89(3):497-517
The research was conducted to investigate comparative oxidative
damage including probable protective roles of antioxidant and glyoxalase systems
in rice (Oryza sativa L.) seedlings under salinity stress. Seedlings of two rice genotypes: Pokkali (tolerant) and BRRI dhan28 (sensitive) were subjected to 8 dSm−1
salinity stress for seven days in a hydroponic system. We observed significant variation between Pokkali and BRRI dhan28 in phenotypic, biochemical and molecular level under salinity stress. Carotenoid content, ion homeostasis, antioxidant
enzymes, ascorbate and glutathione redox system and proline accumulation may
help Pokkali to develop defense system during salinity stress. However, the activity antioxidant enzymes particularly superoxide dismutase (SOD), catalase (CAT)
and non-chloroplastic peroxidase (POD) were observed significantly higher in
Pokkali compared to salt-sensitive BRRI dhan28. Higher glyoxalase (Gly-I)
and glyoxalase (Gly-II) activity might have also accompanied Pokkali genotype
to reduce potential cytotoxic MG through non-toxic hydroxy acids conversion.
However, the efficient antioxidants and glyoxalase system together increased
adaptability in Pokkali during salinity stress. 相似文献
119.
PETER J. WANIEK LEILA MENDONÇA‐LIMA GUSTAVO B. MENEZES ANA M. JANSEN CATARINA A. C. ARAÚJO 《Physiological Entomology》2009,34(4):309-317
Insect c‐type lysozymes are antibacterial proteins that are synthesized in different organs with high activity against Gram‐positive bacteria. Because lysozymes possess muramidase activity, they also play an important role in the digestion of bacteria in Diptera. Triatomines express lysozyme‐encoding genes constitutively in the anterior region (cardia and stomach) of the midgut and the fat body after injection of bacteria into the haemocoel. The present study describes the overexpression of the Triatoma brasiliensis lysozyme 1 (lys1) in Escherichia coli. Recombinant T. brasiliensis Lys1 (TbLys1) is purified after solubilization of the inclusion bodies. The protein refolds successfully, showing muramidase activity against Micrococcus lysodeikticus lyophilized cells, after enterokinase cleavage of its thioredoxin fusion protein. In in‐gel zymograms and turbidimetric liquid assays TbLys1 is broadly active under alkaline and acid conditions, indicating a possible digestive function in the two physiologically different midgut regions of the bug: the stomach and small intestine. Muramidase activity is shown in the stomach and small intestine content of unfed bugs and bugs at different days after feeding, respectively. Western blot analysis identifies TbLys1 as lysozyme. 相似文献
120.
ANNA MARTINEZ EL MOUKHTAR ALIOUAT MURIEL POTTIER NAUSICÂA GANTOIS CLAIRE PINÇON ANNIE STANDAERT-VITSE EDUARDO DEI-CAS CÉCILE-MARIE ALIOUAT-DENIS 《The Journal of eukaryotic microbiology》2009,56(5):446-453
ABSTRACT. The separation of Pneumocystis carinii life-cycle stages while preserving infectivity is a hitherto unresolved challenge. We describe an original, reproducible, and efficient method for separating trophic from cystic forms of P. carinii using a high-speed cell sorter. The large amounts of highly purified (99.6±0.3%) infectious trophic and cystic forms can now be used to elucidate the poorly understood P. carinii life cycle. 相似文献