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41.
The ability to detect DNA damage using the alkaline comet assay depends on pH, lysis time and temperature during lysis. However, it is not known whether different lysis conditions identify different types of DNA damage or simply measure the same damage with different efficiencies. Results support the latter interpretation for radiation, but not for the alkylating agent MNNG. For X-ray-induced damage, cells showed the same amount of damage, regardless of lysis pH (12.3 compared to >13). However, increasing the duration of lysis at 5 degrees C from 1 h to more than 6 h increased the amount of DNA damage detected by almost twofold. Another twofold increase in apparent damage was observed by conducting lysis at room temperature (22 degrees C) for 6 h, but at the expense of a higher background level of DNA damage. The oxygen enhancement ratio and the rate of rejoining of single-strand breaks after irradiation were similar regardless of pH and lysis time, consistent with more efficient detection of strand breaks rather than detection of damage to the DNA bases. Conversely, after MNNG treatment, DNA damage was dependent on both lysis time and pH. With the higher-pH lysis, there was a reduction in the ratio of oxidative base damage to strand breaks as revealed using treatment with endonuclease III and formamidopyrimidine glycosylase. Therefore, our current results support the hypothesis that the increased sensitivity of longer lysis at higher pH for detecting radiation-induced DNA damage is due primarily to an increase in efficiency for detecting strand breaks, probably by allowing more time for DNA unwinding and diffusion before electrophoresis. 相似文献
42.
Multiplexed genotyping with sequence-tagged molecular inversion probes 总被引:19,自引:0,他引:19
Hardenbol P Banér J Jain M Nilsson M Namsaraev EA Karlin-Neumann GA Fakhrai-Rad H Ronaghi M Willis TD Landegren U Davis RW 《Nature biotechnology》2003,21(6):673-678
We report on the development of molecular inversion probe (MIP) genotyping, an efficient technology for large-scale single nucleotide polymorphism (SNP) analysis. This technique uses MIPs to produce inverted sequences, which undergo a unimolecular rearrangement and are then amplified by PCR using common primers and analyzed using universal sequence tag DNA microarrays, resulting in highly specific genotyping. With this technology, multiplex analysis of more than 1,000 probes in a single tube can be done using standard laboratory equipment. Genotypes are generated with a high call rate (95%) and high accuracy (>99%) as determined by independent sequencing. 相似文献
43.
Urasaki N Tokumoto M Terauchi R Tarora K Chinen I Ban Y Kayano T Tanaka H 《Genes & genetic systems》2000,75(5):293-298
In the course of papaya EST collection, one clone (pRA4-3) encoding partial sequence of papaya small GTP-binding protein gene, pgp1, was obtained. Based on the sequence information of pRA4-3, the entire coding region of pgp1 was cloned using the 3'RACE PCR technique. ORF of pgp1 is 636bp long and deduced molecular weight of the protein is 23,311. Phylogenetic analysis showed that PGP1 belongs to YPT/RAB group of the small GTP-binding protein and is a homologue of RAB2. Southern analysis showed that there are several pgp1-related genes in papaya genome. Northern analysis showed that pgp1 was expressed equally in stems of seedlings that were grown under light and dark conditions. This result shows that PGP1 is not involved in the phytochrome-mediated signal transduction as an auxin signal transducer in stems of papaya seedlings. 相似文献
44.
A sensor consisting of a wooden monitor painted with a conductive circuit of silver particle emulsion was placed in a monitoring station to detect feeding activity of the subterranean termite Coptotermes havilandi Holmgren. Sensor accuracy was 100% 1 mo after installation, but 9 mo after sensor placement, the rate declined to 73%. After the detection of C. havilandi in the stations, baits containing the chitin synthesis inhibitor hexaflumuron were applied in five colonies, and four colonies were eliminated within 3-5 mo. Baiting could not be completed for the remaining one colony because the site became inaccessible. 相似文献
45.
Ban J Maysinger D Kovac V Galetić I Matulić M Hadzija M Uzarević B 《Life sciences》2000,68(2):165-175
Potassium bisperoxo(1,10-phenanthroline)oxovanadate, bpV(phen), a powerful protein phosphotyrosine phosphatase inhibitor and a potent insulinomimetic, influenced three fundamental cellular processes in HL-60 human leukemic cells: 1) inhibition of proliferation, 2) induction of differentiation and 3) apoptotic cell death. In the presence of micromolar concentrations of bpV(phen) cell number and DNA synthesis decreased progressively with time of incubation. A single treatment with bpV(phen) (3 microM) activated a differentiation program; after 6 days of incubation 82% of cells were differentiated, but differentiation started already within the first 24 h. Concentrations of 5-10 microM bpV(phen) caused the characteristic DNA ladder pattern, starting after 4.5 h. Differentiation in HL-60 cells appear to be associated with activation of extracellular signal-regulated kinase while apoptosis is connected with phosphorylation and activation of both extracellular signal-regulated kinase and c-Jun N-terminal kinase in a concentration and time-dependent manner. The antiproliferative and apoptotic action of bpV(phen) could be exploited in combination chemotherapy in leukemia. 相似文献
46.
The life cycles of Cyclops vicinus and Thermocyclops crassusin two shallow eutrophic habitats, Junsainuma and Naganuma Ponds,Hokkaido, Japan, were investigated. Both ponds exhibited similarseasonal patterns of temperature, oxygen levels and pH duringice-free periods; however, oxygen levels were extremely lowerunder the ice in Naganuma Pond. Cyclops vicinus showed differentlife cycles in the two ponds; in Junsainuma Pond, it reproducedin winter and spring (January-May) and entered diapause duringsummer and autumn (June-October) as copepodite IV stage, whileit reproduced in autumn (October-November) and spring (April-May),and entered diapause in summer (June-September) and winter (Januaryand February) as copepodite V stage in Naganuma Pond. Thermocyclopscrassus entered diapause during winter (December-April) as copepoditeIV and V stages in both ponds, and egg-bearing females appearedonly during the warmseason, from early May to late October,when water temperatures were >10°C. Summer diapause inC.vicinus was suggested to be an adaptation against fish predation,whereas C.vicinus entered winter diapause in Naganuma Pond probablyto avoid low oxygen levels. Thermocyclops crassus entered diapausein both ponds to avoid low water temperature. These resultssuggest that biotic and abiotic factors are important for leadingto specific life cycles of cyclopoid copepods in small waterbodies. 相似文献
47.
Eyelid opening stretches mechanoreceptors in the supratarsal Müller muscle to activate the proprioceptive fiber supplied by the trigeminal mesencephalic nucleus. This proprioception induces reflex contractions of the slow-twitch fibers in the levator palpebrae superioris and frontalis muscles to sustain eyelid and eyebrow positions against gravity. The cell bodies of the trigeminal proprioceptive neurons in the mesencephalon potentially make gap-junctional connections with the locus coeruleus neurons. The locus coeruleus is implicated in arousal and autonomic function. Due to the relationship between arousal, ventromedial prefrontal cortex, and skin conductance, we assessed whether upgaze with trigeminal proprioceptive evocation activates sympathetically innervated sweat glands and the ventromedial prefrontal cortex. Specifically, we examined whether 60° upgaze induces palmar sweating and hemodynamic changes in the prefrontal cortex in 16 subjects. Sweating was monitored using a thumb-mounted perspiration meter, and prefrontal cortex activity was measured with 45-channel, functional near-infrared spectroscopy (fNIRS) and 2-channel NIRS at Fp1 and Fp2. In 16 subjects, palmar sweating was induced by upgaze and decreased in response to downgaze. Upgaze activated the ventromedial prefrontal cortex with an accumulation of integrated concentration changes in deoxyhemoglobin, oxyhemoglobin, and total hemoglobin levels in 12 subjects. Upgaze phasically and degree-dependently increased deoxyhemoglobin level at Fp1 and Fp2, whereas downgaze phasically decreased it in 16 subjects. Unilateral anesthetization of mechanoreceptors in the supratarsal Müller muscle used to significantly reduce trigeminal proprioceptive evocation ipsilaterally impaired the increased deoxyhemoglobin level by 60° upgaze at Fp1 or Fp2 in 6 subjects. We concluded that upgaze with strong trigeminal proprioceptive evocation was sufficient to phasically activate sympathetically innervated sweat glands and appeared to induce rapid oxygen consumption in the ventromedial prefrontal cortex and to rapidly produce deoxyhemoglobin to regulate physiological arousal. Thus, eyelid opening with trigeminal proprioceptive evocation may activate the ventromedial prefrontal cortex via the mesencephalic trigeminal nucleus and locus coeruleus. 相似文献
48.
Xiang Sun Jinghao Ban Xinjia Sha Weiguo Wang Yang Jiao Wanshan Wang Yanwei Yang Jingjing Wei Lijuan Shen Jihua Chen 《PloS one》2015,10(11)
Background
The objective of this study was to investigate the influence of Er,Cr:YSGG laser irradiated at different powers on the micromorphology and the bonding property of non-carious sclerotic dentin to resin composites.Methods
Two hundred bovine incisors characterized by non-carious sclerotic dentin were selected, and the seventy-two teeth of which for surface morphological analysis were divided into nine groups according to various treatments (A: the control group, B: only treated with the adhesive Adper Easy One, C: diamond bur polishing followed by Adper Easy One, D-I: Er,Cr:YSGG laser irradiating at 1W, 2W, 3W, 4W, 5W, 6W output power, respectively, followed by Adper Easy One). The surface roughness values were measured by the non-contact three-dimensional morphology scanner, then the surface micromorphologies of surfaces in all groups were assessed by scanning electron microscopy (SEM); meanwhile, Image Pro-Plus 6.0 software was used to measure the relative percentage of open tubules on SEM images. The rest, one hundred twenty-eight teeth for bond strength test, were divided into eight groups according to the different treatments (A: only treated with the adhesive Adper Easy One, B: diamond bur polishing followed by the above adhesive, C-H: Er,Cr:YSGG laser irradiating at 1 W, 2 W, 3 W, 4 W, 5 W, 6 W output power, respectively, followed by the above adhesive), and each group was subsequently divided into two subgroups according to whether aging is performed (immediately tested and after thermocycling). Micro-shear bond strength test was used to evaluate the bond strength.Results
The 4W laser group showed the highest roughness value (30.84±1.93μm), which was statistically higher than the control group and the diamond bur groups (p<0.05). The mean percentages ((27.8±1.8)%, (28.0±2.2)%, (30.0±1.9)%) of open tubules area in the 4W, 5W, 6W group were higher than other groups (p<0.05). The 4W laser group showed the highest micro-shear bond strength not only in immediately tested (17.60±2.55 PMa) but after thermocycling (14.35±2.08MPa).Conclusion
The Er,Cr:YSGG laser at 4W power can effectively improve the bonding property between non-carious sclerotic dentin and resin composites by increasing the roughness and mean percentage area of open tubules. 相似文献49.
Zhang Yong Xia Qin Jian Sun Hua Yang Ming Xia Zhang Ru Ban Ge Lin Xu Ya Ping Wu Le Xin Wang Yi Feng Du 《PloS one》2015,10(6)
Background and Objectives
Carotid artery stenting (CAS) is an important therapeutic strategy for patients with carotid artery stenosis. However, the potential influence of CAS on cognitive function in patients with carotid artery stenosis and cerebral lacunar infarction has not been determined. This study investigated changes in cognitive function associated with CAS and the factors related to these changes.Methods
This prospective cohort study comprised 579 Chinese patients with cerebral lacunar infarction and carotid artery stenosis for whom CAS was indicated, and a matched control group of 552 healthy individuals. Cognitive function before CAS and at scheduled intervals from 6 months to 3 years was assessed with instruments that included the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scale. Potential factors that might affect cognitive function were analyzed via logistic regression.Results
The MMSE and MoCA scores of the patients before CAS were significantly lower than that of the control subjects. These scores were significantly higher 6 months after CAS and sustained or increased throughout the 3-year follow-up. Also significantly improved after CAS from baseline were scores for an alternating trail test, cube copying, clock-drawing, attention, and delayed recall in an auditory-verbal learning test. Logistic regression analyses showed that age greater than 65 y, little education, diabetes, and hypertension were independent risk factors for deteriorated MoCA scores 3 years after CAS.Conclusion
CAS was associated with significantly improved cognitive function in cerebral lacunar infarction patients with severe stenosis. 相似文献50.
Stacy E. Aguilera Jennifer Cole Elena M. Finkbeiner Elodie Le Cornu Natalie C. Ban Mark H. Carr Joshua E. Cinner Larry B. Crowder Stefan Gelcich Christina C. Hicks John N. Kittinger Rebecca Martone Daniel Malone Carrie Pomeroy Richard M. Starr Sanah Seram Rachel Zuercher Kenneth Broad 《PloS one》2015,10(3)
Globally, small-scale fisheries are influenced by dynamic climate, governance, and market drivers, which present social and ecological challenges and opportunities. It is difficult to manage fisheries adaptively for fluctuating drivers, except to allow participants to shift effort among multiple fisheries. Adapting to changing conditions allows small-scale fishery participants to survive economic and environmental disturbances and benefit from optimal conditions. This study explores the relative influence of large-scale drivers on shifts in effort and outcomes among three closely linked fisheries in Monterey Bay since the Magnuson-Stevens Fisheries Conservation and Management Act of 1976. In this region, Pacific sardine (Sardinops sagax), northern anchovy (Engraulis mordax), and market squid (Loligo opalescens) fisheries comprise a tightly linked system where shifting focus among fisheries is a key element to adaptive capacity and reduced social and ecological vulnerability. Using a cluster analysis of landings, we identify four modes from 1974 to 2012 that are dominated (i.e., a given species accounting for the plurality of landings) by squid, sardine, anchovy, or lack any dominance, and seven points of transition among these periods. This approach enables us to determine which drivers are associated with each mode and each transition. Overall, we show that market and climate drivers are predominantly attributed to dominance transitions. Model selection of external drivers indicates that governance phases, reflected as perceived abundance, dictate long-term outcomes. Our findings suggest that globally, small-scale fishery managers should consider enabling shifts in effort among fisheries and retaining existing flexibility, as adaptive capacity is a critical determinant for social and ecological resilience. 相似文献