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71.
Mohamed?A.?Wahdan Pieter?Spronck Hamdi?F.?Ali Eddy?Vaassen H.?Jaap?Van Den?HerikEmail author 《Systemic Practice and Action Research》2005,18(6):569-580
Most corporations are required by law to produce annual reports on their financial positions. These financial reports are accompanied by an auditor's report, which is an independent auditor's opinion on the fairness of the financial statements. To formulate their reports, auditors use a “personal-judgement” approach that heavily depends on their experience and expertise. This approach may be (1) ineffective and may lead to (2) different decisions, (3) personal bias, and (4) misleading judgements. These four drawbacks of a human auditor are a source of doubt and hesitation for every corporation. Therefore, the challenging question is: Can a computer do a better job? This paper focuses on the construction and implementation of a knowledge-based system, called the “Auditor's Report EXpert” (AREX), that is capable of formulating the opinion on financial statements, as expressed in the auditor's report. The knowledge used by AREX is acquired from the literature, and from a slate of practicing and academic auditors by means of questionnaires and in-depth interviews. A preliminary validation of AREX indicates that AREX is successful in performing the auditor's report task. Hence, we tentatively conclude that currently a computer program can support an auditor in his/her task. Moreover, in the foreseeable futur's reports that are effective, universal in their decisions, do not show a personal bias, and do not have misleading statements. 相似文献
72.
This paper presents a new methodological approach for the synthesis of a neuro-fuzzy controller, using an on-line learning procedure. A simple algebraic formulation of a Sugeno fuzzy inference system that ensures a coherent universe of discourse, making easy its interpretation by a human being, is proposed and implemented in the case of the control of a bioreactor, which is considered as a complex non linear process. 相似文献
73.
Römer W Berland L Chambon V Gaus K Windschiegl B Tenza D Aly MR Fraisier V Florent JC Perrais D Lamaze C Raposo G Steinem C Sens P Bassereau P Johannes L 《Nature》2007,450(7170):670-675
Clathrin seems to be dispensable for some endocytic processes and, in several instances, no cytosolic coat protein complexes could be detected at sites of membrane invagination. Hence, new principles must in these cases be invoked to account for the mechanical force driving membrane shape changes. Here we show that the Gb3 (glycolipid)-binding B-subunit of bacterial Shiga toxin induces narrow tubular membrane invaginations in human and mouse cells and model membranes. In cells, tubule occurrence increases on energy depletion and inhibition of dynamin or actin functions. Our data thus demonstrate that active cellular processes are needed for tubule scission rather than tubule formation. We conclude that the B-subunit induces lipid reorganization that favours negative membrane curvature, which drives the formation of inward membrane tubules. Our findings support a model in which the lateral growth of B-subunit-Gb3 microdomains is limited by the invagination process, which itself is regulated by membrane tension. The physical principles underlying this basic cargo-induced membrane uptake may also be relevant to other internalization processes, creating a rationale for conceptualizing the perplexing diversity of endocytic routes. 相似文献
74.
Within a short period of time after the discovery of bacterial cytoskletons, major progress had been made in areas such as general spatial layout of cytoskeletons, their involvement in a variety of cellfunctions (shape control, cell division, chromosome segregation, cell motility). This progress was achieved by application of advanced investigation techniques. Homologs of eukaryotic actin, tubulin, and intermediate filaments were found in bacteria; cytoskeletal proteins not closely or not at all related to any of these major cytoskeletal proteins were discovered in a number of bacteria such as Mycoplasmas, Spiroplasmas, Spirochetes, Treponema, Caulobacter. A structural role for bacterial elongation factor Tu was indicated. On the basis of this new thinking, new approaches in biotechnology and new drugs are on the way. 相似文献
75.
Ouria Dkhissi-Benyahya Christine Coutanson Kenneth Knoblauch Hasna Lahouaoui Vincent Leviel Catherine Rey Mohamed Bennis Howard M. Cooper 《Cellular and molecular life sciences : CMLS》2013,70(18):3435-3447
The retinal circadian clock is crucial for optimal regulation of retinal physiology and function, yet its cellular location in mammals is still controversial. We used laser microdissection to investigate the circadian profiles and phase relations of clock gene expression and Period gene induction by light in the isolated outer (rods/cones) and inner (inner nuclear and ganglion cell layers) regions in wild-type and melanopsin-knockout (Opn 4 ?/? ) mouse retinas. In the wild-type mouse, all clock genes are rhythmically expressed in the photoreceptor layer but not in the inner retina. For clock genes that are rhythmic in both retinal compartments, the circadian profiles are out of phase. These results are consistent with the view that photoreceptors are a potential site of circadian rhythm generation. In mice lacking melanopsin, we found an unexpected loss of clock gene rhythms and of the photic induction of Per1-Per2 mRNAs only in the outer retina. Since melanopsin ganglion cells are known to provide a feed-back signalling pathway for photic information to dopaminergic cells, we further examined dopamine (DA) synthesis in Opn 4 ?/? mice. The lack of melanopsin prevented the light-dependent increase of tyrosine hydroxylase (TH) mRNA and of DA and, in constant darkness, led to comparatively high levels of both components. These results suggest that melanopsin is required for molecular clock function and DA regulation in the retina, and that Period gene induction by light is mediated by a melanopsin-dependent, DA-driven signal acting on retinal photoreceptors. 相似文献
76.
Bradfield JP Taal HR Timpson NJ Scherag A Lecoeur C Warrington NM Hypponen E Holst C Valcarcel B Thiering E Salem RM Schumacher FR Cousminer DL Sleiman PM Zhao J Berkowitz RI Vimaleswaran KS Jarick I Pennell CE Evans DM St Pourcain B Berry DJ Mook-Kanamori DO Hofman A Rivadeneira F Uitterlinden AG van Duijn CM van der Valk RJ de Jongste JC Postma DS Boomsma DI Gauderman WJ Hassanein MT Lindgren CM Mägi R Boreham CA Neville CE Moreno LA Elliott P Pouta A Hartikainen AL Li M Raitakari O 《Nature genetics》2012,44(5):526-531
Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made in establishing genetic influences on common early-onset obesity. We performed a North American, Australian and European collaborative meta-analysis of 14 studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight newly discovered signals yielding association with P < 5 × 10(-6) in nine independent data sets (2,818 cases and 4,083 controls), we observed two loci that yielded genome-wide significant combined P values near OLFM4 at 13q14 (rs9568856; P = 1.82 × 10(-9); odds ratio (OR) = 1.22) and within HOXB5 at 17q21 (rs9299; P = 3.54 × 10(-9); OR = 1.14). Both loci continued to show association when two extreme childhood obesity cohorts were included (2,214 cases and 2,674 controls). These two loci also yielded directionally consistent associations in a previous meta-analysis of adult BMI(1). 相似文献
77.
Seyma Bahdoudi Ikram Ghouili Mansour Hmiden Jean-Luc do Rego Benjamin Lefranc Jérôme Leprince Julien Chuquet Jean-Claude do Rego Ann-Britt Marcher Susanne Mandrup Hubert Vaudry Marie-Christine Tonon Mohamed Amri Olfa Masmoudi-Kouki David Vaudry 《Cellular and molecular life sciences : CMLS》2018,75(11):2075-2091
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by a progressive loss of dopamine (DA) neurons through apoptotic, inflammatory and oxidative stress mechanisms. The octadecaneuropeptide (ODN) is a diazepam-binding inhibitor (DBI)-derived peptide, expressed by astrocytes, which protects neurons against oxidative cell damages and apoptosis in an in vitro model of PD. The present study reveals that a single intracerebroventricular injection of 10 ng ODN 1 h after the last administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) prevented the degeneration of DA neurons induced by the toxin in the substantia nigra pars compacta of mice, 7 days after treatment. ODN-mediated neuroprotection was associated with a reduction of the number of glial fibrillary acidic protein-positive reactive astrocytes and a strong inhibition of the expression of pro-inflammatory genes such as interleukins 1β and 6, and tumor necrosis factor-α. Moreover, ODN blocked the inhibition of the anti-apoptotic gene Bcl-2, and the stimulation of the pro-apoptotic genes Bax and caspase-3, induced by MPTP in the substantia nigra pars compacta. ODN also decreased or even in some cases abolished MPTP-induced oxidative damages, overproduction of reactive oxygen species and accumulation of lipid oxidation products in DA neurons. Furthermore, DBI knockout mice appeared to be more vulnerable than wild-type animals to MPTP neurotoxicity. Taken together, these results show that the gliopeptide ODN exerts a potent neuroprotective effect against MPTP-induced degeneration of nigrostriatal DA neurons in mice, through mechanisms involving downregulation of neuroinflammatory, oxidative and apoptotic processes. ODN may, thus, reduce neuronal damages in PD and other cerebral injuries involving oxidative neurodegeneration. 相似文献
78.
Summary Measurements of the asphyxial oxygen level forRhinomugil corsula, Tilapia mossambica, Puntius sarana andCarassius auratus at 30 and 35°C revealed that at 35°C the lethal oxygen level was higher forT. mossambica andP. sarana and lower forR. corsula, but it remained the same forC. auratus at 30 and 35°C.
From a thesis (M.P.M.) approved for the degree of Doctor of Philosophy, Madurai Kamaraj University, madurai, India.
We wish to express our thanks to Prof. S. Krishnaswamy for providing facilities and to Dr S.V. Job for suggestions. 相似文献
79.
Mohamed Gad-el-Hak 《国外科技新书评介》2009,(5)
随着人类生存环境的复杂化、世界多极化和经济全球化,难以预料的全球性气候反常和难以控制的自然灾害时有发生,恐怖事件接连不断,事故灾难频频发生,跨国性的重大疫情等不时出现,这一系列突发事件给人类社会和自然系统带来的灾难是沉重的,世界各国都面临着新的风险和挑战。本书正是对各个领域大规模灾难相关研究进行的总结和回顾,特别关注了由气候变化引起的极端事件,另外还包括空气污染、海啸、灾害模拟、遥感应用以及灾害管理等方面内容。 相似文献
80.
Low gene copy number shows that arbuscular mycorrhizal fungi inherit genetically different nuclei 总被引:1,自引:0,他引:1
Arbuscular mycorrhizal fungi (AMF) are ancient asexually reproducing organisms that form symbioses with the majority of plant species, improving plant nutrition and promoting plant diversity. Little is known about the evolution or organization of the genomes of any eukaryotic symbiont or ancient asexual organism. Direct evidence shows that one AMF species is heterokaryotic; that is, containing populations of genetically different nuclei. It has been suggested, however, that the genetic variation passed from generation to generation in AMF is simply due to multiple chromosome sets (that is, high ploidy). Here we show that previously documented genetic variation in Pol-like sequences, which are passed from generation to generation, cannot be due to either high ploidy or repeated gene duplications. Our results provide the clearest evidence so far for substantial genetic differences among nuclei in AMF. We also show that even AMF with a very large nuclear DNA content are haploid. An underlying principle of evolutionary theory is that an individual passes on one or half of its genome to each of its progeny. The coexistence of a population of many genomes in AMF and their transfer to subsequent generations, therefore, has far-reaching consequences for understanding genome evolution. 相似文献