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991.
Ece Terzioğlu Kara Ferdi Rıdvan Kiral Arzu Öztürk Çolak Arzu Çelik 《Archives of insect biochemistry and physiology》2020,104(2):e21675
The Drosophila inner photoreceptors R7 and R8 are responsible for color vision and their differentiation starts at the third instar larval stage. Only a handful of genes with R7 or R8-cell-specific expression are known. We performed an enhancer-trap screen using a novel piggyBac transposable element, pBGay, carrying a Gal4 sequence under the control of the P promoter to identify novel genes expressed specifically in R7 or R8 cells. From this screen, three lines were analyzed in detail: piggyBacAC109 and piggyBacAC783 are expressed in R8 cells and piggyBacAC887 is expressed in R7 cells at the third instar larval stage and pupal stages. Molecular analysis showed that the piggyBac elements were inserted into the first intron of CG14160 and CG7985 genes and the second intron of unzipped. We show the expression pattern in the developing eye imaginal disc, pupal retina as well as the adult retina. The photoreceptor-specific expression of these genes is reported for the first time and we propose that these lines are useful tools for studying the development of the visual system. 相似文献
992.
Hsp70 and Hsp40 attenuate formation of spherical and annular polyglutamine oligomers by partitioning monomer 总被引:8,自引:0,他引:8
Wacker JL Zareie MH Fong H Sarikaya M Muchowski PJ 《Nature structural & molecular biology》2004,11(12):1215-1222
Protein conformational changes that result in misfolding, aggregation and amyloid fibril formation are a common feature of many neurodegenerative disorders. Studies with beta-amyloid (Abeta), alpha-synuclein and other amyloid-forming proteins indicate that the assembly of misfolded protein conformers into fibrils is a complex process that may involve the population of metastable spherical and/or annular oligomeric assemblies. Here, we show by atomic force microscopy that a mutant huntingtin fragment with an expanded polyglutamine repeat forms spherical and annular oligomeric structures reminiscent of those formed by Abeta and alpha-synuclein. Notably, the molecular chaperones Hsp70 and Hsp40, which are protective in animal models of neurodegeneration, modulate polyglutamine aggregation reactions by partitioning monomeric conformations and disfavoring the accretion of spherical and annular oligomers. 相似文献
993.
Bukem Bilen Fatma Ates Alkan Umit Bora Barutcu Meltem Sezen Mehmet Burcin Unlu Kamran Aghayev 《Journal of medical case reports》2018,12(1):391
Background
Projectile foreign bodies are known to cause chronic heavy metal toxicity due to the release of metal into the bloodstream. However, the local effect around the metallic object has not been investigated and the main goal of our study is to examine the influence of the object in close proximity of the object.Case presentation
A 36-year-old Caucasian woman with one metallic pellet close to her sciatic nerve due to a previous shotgun injury at the gluteal area presented with a diagnosis of recurrent lumbar disk herniation at L4–5 level. A physical examination confirmed chronic neuropathy and she underwent a two-stage surgery. The surgery included removal of the foreign body, followed by discectomy and fusion at the involved level. During the removal of the metallic foreign body, a tissue sample around the pellet and another tissue sample from a remote area were obtained. The samples were analyzed by scanning acoustic microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Lead, chromium, copper, cadmium, iron, manganese, selenium, and zinc elements in tissue, blood, and serum specimens were detected by inductively coupled plasma optical emission spectroscopy.Conclusions
An acoustic impedance map of the tissue closer to the metallic body showed higher values indicating further accumulation of elements. Energy-dispersive X-ray spectroscopy results confirmed scanning acoustic microscopy results by measuring a higher concentration of elements closer to the metallic body. Scanning electron microscopy images showed that original structure was not disturbed far away; however, deformation of the structure existed in the tissue closer to the foreign body. Element analysis showed that element levels within blood and serum were more or less within acceptable ranges; on the other hand, element levels within the tissues showed pronounced differences indicating primarily lead intoxication in the proximity of the metallic body. We can state that residues of metallic foreign bodies of gunshot injuries cause chronic metal infiltration to the surrounding tissue and induce significant damage to nearby neural elements; this is supported by the results of scanning acoustic microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and inductively coupled plasma optical emission spectroscopy.994.
Surface water contamination from agricultural and urban runoff and wastewater discharges from industrial and municipal activities is of major concern to people worldwide. Classical models can be insufficient to visualise the results because the water quality variables used to describe dynamic pollution sources are complex, multivariable, and nonlinearly related. Artificial intelligence techniques with the ability to analyse multivariant water quality data by means of a sophisticated visualisation capacity can offer an alternative to current models. In this study, the Kohonen self-organising feature maps (SOM) neural network was initially applied to analyse the complex nonlinear relationships among multivariable surface water quality variables using the component planes of the variables to determine the complex behaviour of water quality parameters. The dependencies between water quality variables were extracted and interpreted using the pattern analysis visualised in component planes. For further investigation, the k-means clustering algorithm was used to determine the optimal number of clusters by partitioning the maps and utilising the Davies–Bouldin clustering index, leading to seven groups or clusters corresponding to water quality variables. The results reveal that the concentrations of Na, K, Cl, NH4-N, NO2-N, o-PO4, component planes of organic matter (pV), and dissolved oxygen (DO) were significantly affected by seasonal changes, and that the SOM technique is an efficient tool with which to analyse and determine the complex behaviour of multidimensional surface water quality data. These results suggest that this technique could also be applied to other environmentally sensitive areas such as air and groundwater pollution. 相似文献
995.
Prof. Dr. Veysel Çomaklı Dr. Rüya Sağlamtaş Prof. Dr. Müslüm Kuzu Dr. Yalçın Karagöz Assoc. Prof. Dr. Tuba Aydın Prof. Dr. Ramazan Demirdağ 《化学与生物多样性》2023,20(5):e202201231
In the study, water, ethanol, methanol, dichloromethane, and acetone extracts of Asparagus officinalis L. were obtained by maceration. DPPH⋅, ABTS⋅+, FRAP, and CUPRAC methods determined the antioxidant capacities of all extracts. Moreover, the in vitro effects of extracts on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carbonic anhydrase (CA)-I, CA-II and α-Glycosidase were investigated. At a 10 μg/ml concentration, the extract with the highest Fe3+ reduction capacity was ethanol (AE), and the extract with the highest Cu2+ reduction capacity was acetone (AA). AE for AChE (IC50=21.19 μg/ml) and α-Glycosidase (IC50: 70.00 μg/ml), methanol (AM) for BChE (IC50=17.33 μg/ml), CA−I and II (IC50=79.65 and 36.09 μg/ml, respectively) showed the most potent inhibition effect. The content analysis of acetone extract was performed with LC/MS-MS, the first three phytochemicals found most were p-Coumaric acid, rutin, and 4-hydroxybenzoic acid (284.29±3.97, 135.39±8.19, and 102.06±5.51 μg analyte/g extract, respectively). 相似文献
996.
997.
Serdar Oztuzcu Mustafa Ulaşlı Sercan Ergun Yusuf Ziya Iğci Mehri Iğci Recep Bayraktar Gülper Nacarkahya Ali Tamer Muammer Özgür Çevik Ecir Ali Çakmak Ahmet Arslan 《Molecular biology reports》2014,41(4):2601-2607
Familial mediterranean fever (FMF) is an autosomal recessive autoinflammatory disorder (MIM# 249100), particularly common in populations of Mediterranean extraction. MEFV gene, responsible for FMF, encoding pyrin has recently been mapped to chromosome 16p13.3. In the present study, 3,341 unrelated patients with the suspicion of FMF in south-east part of Turkey between the years 2009 and 2013 were enrolled and genomic sequences of exon 2 and exon 10 of the MEFV gene were scanned for mutations by direct sequencing. We identified 43 different type of mutations and 9 of them were novel. DNA was amplified by PCR and subjected to direct sequencing for the detection of MEFV gene mutations. Among the 3,341 patients, 1,598 (47.8 %) were males and 1,743 (52.1 %) were females. The mutations were heterozygous in 806 (62.3 %), compound heterozygous in 188 (14.5 %), homozygous in 281 (21.8 %) and mutations had complex genotype in 17 (1.32 %) patients. No mutation was detected in 2,051 (61.4 %) patients. The most frequent mutations were M694V, E148Q, M680I(G/C) and V726A. We could not find any significant differences between the two common mutations according to the gender. Molecular diagnosis of MEFV is a useful tool in clinical practice, thus a future study relating to genotype/phenotype correlation of FMF in more and larger group in Turkish population involving the whole MEFV gene mutations is necessary. 相似文献
998.
Serdar Ünlü Erden Banoglu Shigeru Ito Tokihiro Niiya Gökçen Eren Berna Ökçelik 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):351-361
In a search for novel compounds with analgesic and anti-inflammatory activity, a series of regioisomeric 1-(3-pyridazinyl)-3-arylpyrazole (5a–f, 6a–f) and 1-(3-pyridazinyl)-5-arylpyrazole (7a–f, 8a–f) derivatives were synthesized. The structure of these regioisomers was confirmed by spectral techniques. The compounds were preliminarily screened at 8 μM concentration for their inhibitory activity against cyclooxygenase enzymes, COX-1 and COX-2, using a human whole blood test. The tested derivatives showed inhibitory activity for both enzymes and are worthy of further investigation for developing better leads. 相似文献
999.
1000.
Cristina?JaénEmail author Mehmet?Hakan?Ozdener Johannes?Reisert 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(4):339-349
Odorant stimulation of olfactory receptor neurons (ORNs) leads to the activation of a Ca2+ permeable cyclic nucleotide-gated (CNG) channel followed by opening of an excitatory Ca2+-activated Cl− channel, which carries about 70% of the odorant-induced receptor current. This requires ORNs to have a [Cl−]i above the electrochemical equilibrium to render this anionic current excitatory. In mammalian ORNs, the Na+-K+-2Cl− co-transporter 1 (NKCC1) has been characterized as the principal mechanism by which these neurons actively accumulate Cl−. To determine if NKCC activity is needed in amphibian olfactory transduction, and to characterize its cellular location,
we used the suction pipette technique to record from Rana pipiens ORNs. Application of bumetanide, an NKCC blocker, produced a 50% decrease of the odorant-induced current. Similar effects
were observed when [Cl−]i was decreased by bathing ORNs in low Cl− solution. Both manipulations reduced only the Cl− component of the current. Application of bumetanide only to the ORN cell body and not to the cilia decreased the current
by again about 50%. The results show that NKCC is required for amphibian olfactory transduction, and suggest that the co-transporter
is located basolaterally at the cell body although its presence at the cilia could not be discarded. 相似文献