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991.
Weiying Pan Chanteé M. Dancik Valery M. Nelson Zhi-Gang Jiang Michael S. Lebowitz Hossein A. Ghanbari 《Central European Journal of Biology》2009,4(1):34-40
Hydrogen peroxide (H2O2), a major non-radical reactive oxygen species (ROS) could elicit intracellular oxidative damage and/or cause extracellular
free calcium influx by activating the NMDA receptor or through calcium channels. In the present study, NMDA receptor antagonist
MK-801 fully blocked H2O2-induced neuronal cell death, whereas green tea (GT) extract containing-antioxidants only partially suppressed the neurotoxicity
of H2O2. These suggest that majority of ROS overproduction is downstream of H2O2-induced calcium influx. A novel neuroprotectant PAN-811 was previously demonstrated to efficiently attenuate ischemic neurotoxicity.
PAN-811 hereby fully blocks H2O2-elicited neuronal cell death with a more advanced neuroprotective profile than that of GT extract. PAN-811 was also shown
to protect against CaCl2-elicited neurotoxicity. Efficient protection against oxidative stress-induced neurotoxicity by PAN-811 indicates its potential
application in treatment of ROS-mediated neurodegenerative diseases.
W.P. and C.M.D. had equal contributions to this project 相似文献
992.
This study is focused on the sedimentary environments, facies distribution, and sequence stratigraphy of the Coniacian–Santonian
sediments of the Bangestan Palaeo-high in the Bangestan Anticline (Zagros, Iran). These sediments are subdivided into nine
microfacies types belonging to various sedimentary environments, ranging from continental lacustrine to very shallow and relatively
deep-water (hemipelagic to pelagic) marine environments. The lower boundary of the studied sections is characterised by an
unconformity. The lacustrine and very shallow marine sediments at the base of the studied sections are interpreted as a lowstand
system tract. The establishment of an open shelf carbonate platform took place during the transgressive system tract. The
maximum flooding zone of the Early Santonian is an important surface because it extends from the distal to the proximal part
of the depositional environment. 相似文献
993.
George A. Khoury Hossein Fazelinia Jonathan W. Chin Robert J. Pantazes Patrick C. Cirino Costas D. Maranas 《Protein science : a publication of the Protein Society》2009,18(10):2125-2138
In this study we introduce a computationally‐driven enzyme redesign workflow for altering cofactor specificity from NADPH to NADH. By compiling and comparing data from previous studies involving cofactor switching mutations, we show that their effect cannot be explained as straightforward changes in volume, hydrophobicity, charge, or BLOSUM62 scores of the residues populating the cofactor binding site. Instead, we find that the use of a detailed cofactor binding energy approximation is needed to adequately capture the relative affinity towards different cofactors. The implicit solvation models Generalized Born with molecular volume integration and Generalized Born with simple switching were integrated in the iterative protein redesign and optimization (IPRO) framework to drive the redesign of Candida boidinii xylose reductase (CbXR) to function using the non‐native cofactor NADH. We identified 10 variants, out of the 8,000 possible combinations of mutations, that improve the computationally assessed binding affinity for NADH by introducing mutations in the CbXR binding pocket. Experimental testing revealed that seven out of ten possessed significant xylose reductase activity utilizing NADH, with the best experimental design (CbXR‐GGD) being 27‐fold more active on NADH. The NADPH‐dependent activity for eight out of ten predicted designs was either completely abolished or significantly diminished by at least 90%, yielding a greater than 104‐fold change in specificity to NADH (CbXR‐REG). The remaining two variants (CbXR‐RTT and CBXR‐EQR) had dual cofactor specificity for both nicotinamide cofactors. 相似文献
994.
Reza?Kachuei Mohammad Hossein?Yadegari?Email author Sasan?Rezaie Abdolamir?Allameh Naser?Safaie Farideh?Zaini Fatemeh?Khanezad?Yazdi 《Annals of microbiology》2009,59(2):383
Wheat is the most important cereal produced in Iran. A mycological survey was carried out for the first time, on the stored wheat samples in Tehran, East Azarbayejan and Mazandaran provinces in 2007. Exogenous and endogenous fungi, were isolated by the method of flotation with Malachite green agar (MGA 0.25) and Freeze blotter techniques respectively. In this study, 46 species belonging to 23 different genera were isolated.Cladosporium spp. (57.1–89.2%) andAlternaria spp. (82.4–100%) species were the predominant fungal species identified as endogenous mycoflora. The predominant exogenous fungi werePenicillium spp. (78.4–92.8%) andAspergillus spp. (71.4–85.7%) species.Fusarium proliferatum was the most prevalent species ofFusarium isolates.Aspergillus niger (39.4%) andAspergillus flavus (36.7%) were the predominantAspergillus species identified as exogenous mycoflora.Aspergillus flavus (26.6%) was the predominantAspergillus species identified as endogenous mycoflora. Flotation method with MGA 0.25 recommended for isolating of hyaline fungi from wheat cereals. In this study one isolate fromFusarium species was isolated on the basis of morphology and ribosomal internal transcribed spacer classified asFusarium langsethiae but on the basis of partial translation elongation factor-1alpha gene grouped withFusarium sporotrichioides. To our knowledge, this is the first report aboutF. cf.langsethiae in Iran and Asia. 相似文献
995.
Amygdalus kurdistanica Attar, Maroofi & Vafadar and A. orazii Maroofi, Attar & Vafadar, two new species of the genus Amygdalus L. from western Iran are described and illustrated. Amygdalus kurdistanica is closely related to A. haussknechtii (C. K. Schneider) Bornm. var. pubescens but differs by leaf and petiole size, drupe shape, pedicel indumentum and style length. Amygdalus orazii is closely related to A. communis L. but can be distinguished from A. communis by the following characters: leaf and petiole size, drupe size, pedicel length and sepal length. 相似文献
996.
Mohammad Shamim Hossein Yeon Woo Jeong Sun Woo Park Joung Joo Kim Eugine Lee Kyeong Hee Ko Park Hyuk Song Seung Hoon Yeun Wook Kim Sang Hwan Hyun Taeyoung Shin Woo Suk Hwang 《Animal reproduction science》2009
The present study was undertaken to evaluate two enucleation methods for somatic cell nuclear transfer (SCNT), and to standardize the optimum number of embryos for transfer to each recipient for canines. Oocytes retrieved from outbreed dogs were reconstructed with adult somatic cells from a male Beagle dog. A total of 134 or 267 oocytes were enucleated either by aspiration or squeezing method, fused with two DC pulses of 1.75 kV/cm for 15 μs electrical stimulation, chemically activated after 1 h of fusion using 10 μM calcium ionophore for 4 min and cultured 4 h in 1.9 mM 6-dimethylaminopurine. Finally, 103 or 214 embryos for aspiration or squeezing method were transferred to 6 or 11 naturally synchronized recipients, respectively. A total of 53, 317 and 342 embryos were transferred to 7, 17 and 12 recipients for the group of 4–10, 11–25 and 26–40 embryos, respectively. There was no difference between fusion rate (76.87% vs. 80.15%), full term pregnancy rate (16.66% vs. 27.27%) and percent of live puppies born (0.97% vs. 1.87%) for aspiration and squeezing method (P > 0.05). Production efficiency of cloned dogs was significantly affected by the number of embryos transferred to each recipient. No pregnancy was established for the group of 4–10 embryos (n = 7) and 26–40 embryos (n = 12) while pregnancy was detected in 23.53% recipients received a group of 11–25 embryos (n = 17). Among them, five (1.76%) live puppies were born (P < 0.05). These data show an increase in the overall efficiency of SCNT in canine species. 相似文献
997.
Mojdeh Ghabaee Motahar Omranisikaroudi Shahla Amrisaroukolaei Alipasha Meysamie Mohammad Ali Sahraian Asghar Bayati Mohammad Hossein Sanati Mossoud Houshman Homa Sadeghian Khalili Vajihazaman 《Cellular and molecular neurobiology》2009,29(3):341-346
As multiple sclerosis (MS) has long been known to be associated with Leber, hereditary optic neuropathy (LHON), a disease
caused by mitochondrial (mtDNA) mutations, in this study we assessed possible involvement of mtDNA point mutation in MS patients.
Fifty-two MS patients whose disease was confirmed with revised McDonald criteria and referred to Iranian Center of Neurological
Research of Imam Khomeini hospital during 2006–2007 entered the study. Secondary mtDNA mutations, age, gender, clinical disability
according to expanded disability status scale (EDSS), course of the disease, and presenting symptoms were the variables investigated
in this study. DNA purification was performed by Diatom DNA Extraction Kit. Analysis of data was done by SPSS V11.5. The prevalent
mutations with frequency of 19.2% were J, L, and T haplogroups. Haplotype A was more prevalent in patients with younger age
of onset (P-value = 0.012) and high proportion of haplogroup H was associated with optic nerve involvement (P-value = 0.015). No motor symptoms were seen in haplogroup H patients. There is no significant relationship between duration
of the disease and EDSS in different mutation of mtDNA. 相似文献
998.
Hossein Alaei Mathias De Backer Jorinde Nuytinck Martine Maes Monica Höfte Kurt Heungens 《Mycological Research》2009,113(6-7):668-683
Isolates of the most important Puccinia species that have been reported on Chrysanthemum × morifolium were collected and the sequences of their ribosomal DNA internal transcribed spacers ITS1 and ITS2 were determined and used as phylogenetic markers. The focus of this study was on Puccinia horiana, due to its quarantine status and its impact in commercial chrysanthemum production. Three technical adjustments were needed to reliably obtain the nucleotide sequences starting from fresh or dried samples. The complete rDNA ITS nucleotide sequences of P. horiana, Puccinia chrysanthemi, and Puccinia tanaceti isolates of varying age and geographic origin were determined. We also identified an as yet undescribed Puccinia species on six old herbarium samples from chrysanthemum. This new species is morphologically similar to P. chrysanthemi and near identical to recent rust samples from Artemisia tridentata. P. tanaceti could not be confirmed as a pathogen of chrysanthemum. Different rDNA ITS sequences were present in P. horiana, with intra-isolate and inter-isolate variability in the length of three nucleotide repeat regions in the different rDNA tandem copies. We also identified three ITS types within P. horiana, with the rarer types displaying up to 67 bp nucleotide sequence differences. These rarer ITS types were detected at low copy number in all isolates. In general, very little rDNA ITS sequence variation was observed between P. horiana isolates from 1903 and 2003, and among isolates from different continents. Phylogenetic analyses using distance, Maximum Likelihood and Bayesian methods confirmed P. horiana, P. chrysanthemi, and the new Puccinia sp. as well-resolved groups, with P. horiana clustering in the clade where the economically important rust species of the Poaceae are located, and P. chrysanthemi and the new Puccinia sp. clustering in the clade where the majority of the rust fungi with hosts in the Asteraceae is located. 相似文献
999.
Ghasemi Younes Mohagheghzadeh Abdolali Moshavash Maryam Ostovan Zahra Rasoul-Amini Sara Morowvat Mohammad Hossein Ghoshoon Mohammad Bagher Raee Mohammad Javad Mosavi-Azam Seyed Bagher 《World journal of microbiology & biotechnology》2009,25(7):1301-1304
The biotransformation of several monoterpenes by the locally isolated unicellular microalga, Oocystis pusilla was investigated. The metabolites were identified by thin layer chromatography and GC/MS. The results showed that O. pusilla had the ability to reduce the C=C double bond in (+)-carvone to yield trans-dihydrocarvone and traces of cis-dihydrocarvone. O. pusilla also converted (+)-limonene to trans-carveol, as the main product, and yielded carvone and trans-limonene oxide. Furthermore, (−)-linalool was converted to trans-furanoid and trans-pyranoid linalool oxide, thymol was converted to thymoquinone, (−)-carveol was converted to carvone and trans-dihydrocarvone, (−)-menthone and (+)-pulegone were converted to menthol, (L)-citronellal was converted to citronellol, and
(+)-β-pinene was converted to trans-pinocarveol. 相似文献
1000.
Ewa Kolosionek Rajkumar Savai Hossein Ardeschir Ghofrani Norbert Weissmann Andreas Guenther Friedrich Grimminger Werner Seeger Gamal Andre Banat Ralph Theo Schermuly Soni Savai Pullamsetti 《Molecular biology of the cell》2009,20(22):4751-4765
Epithelial–mesenchymal transition (EMT) has emerged as a critical event in the pathogenesis of organ fibrosis and cancer and is typically induced by the multifunctional cytokine transforming growth factor (TGF)-β1. The present study was undertaken to evaluate the potential role of phosphodiesterases (PDEs) in TGF-β1-induced EMT in the human alveolar epithelial type II cell line A549. Stimulation of A549 with TGF-β1 induced EMT by morphological alterations and by expression changes of the epithelial phenotype markers E-cadherin, cytokeratin-18, zona occludens-1, and the mesenchymal phenotype markers, collagen I, fibronectin, and α-smooth muscle actin. Interestingly, TGF-β1 stimulation caused twofold increase in total cAMP-PDE activity, contributed mostly by PDE4. Furthermore, mRNA and protein expression demonstrated up-regulation of PDE4A and PDE4D isoforms in TGF-β1-stimulated cells. Most importantly, treatment of TGF-β1 stimulated epithelial cells with the PDE4-selective inhibitor rolipram or PDE4 small interfering RNA potently inhibited EMT changes in a Smad-independent manner by decreasing reactive oxygen species, p38, and extracellular signal-regulated kinase phosphorylation. In contrast, the ectopic overexpression of PDE4A and/or PDE4D resulted in a significant loss of epithelial marker E-cadherin but did not result in changes of mesenchymal markers. In addition, Rho kinase signaling activated by TGF-β1 during EMT demonstrated to be a positive regulator of PDE4. Collectively, the findings presented herein suggest that TGF-β1 mediated up-regulation of PDE4 promotes EMT in alveolar epithelial cells. Thus, targeting PDE4 isoforms may be a novel approach to attenuate EMT-associated lung diseases such as pulmonary fibrosis and lung cancer. 相似文献