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51.
Hamid Bou Saab Samuel Fouchard Anna Boulanger Pierre Llopiz Serge Neunlist 《Journal of industrial microbiology & biotechnology》2013,40(11):1315-1320
Bioconversion of lipophilic compounds poorly soluble in water, such as sterols, required the use of chemicals and solubilizing agents. On the other hand, it was shown that immobilization of Mycobacterium species on the dried fruit of Luffa cylindrica (DFLC) allows a close interaction between immobilized cells and cholesterol particles and increases by then the product’s yield. In this work, the use of DFLC in a 5-l jar bioreactor with phytosterols mixture (1 g/l) as substrate was assessed without addition of any chemicals or solubilizing agents. DFLC increased by a factor of four the volumetric productivity of androstenones (0.08 g/l day). Products were accumulated in the aqueous medium while substrates remained on the fibers of DFLC. This observation lets envisage a green semi-continuous process of androstenone production. DFLC has no influence on cell growth, and is moreover natural, inexpensive, non-toxic, and mechanically strong. 相似文献
52.
53.
Bou Gerelchimeg Liu Li-Qing Zheng Zhong Tian Jiang-Tian Kong Qing-Ran Song Jun Wang Xue-Dong Liu Zhong-Hua 《Cryobiology》2009,59(1):54-58
The potential subcellular consequence of chilling on porcine germinal vesicle (GV) stage oocytes was examined. Prior to in vitro maturation (IVM), Cumulus-oocyte complexes (COCs) freshly collected from antral follicles (3–6 mm in diameter) were evenly divided into four groups and immediately incubated in PVA-TL-HEPES medium at the temperature of 39 °C (control group), 23 °C (room temperature), 15 °C and 10 °C for 10 min, respectively. Following 42 h of IVM at 39 °C, the survival rates were examined. There was no significant difference between the survival rate of 23 °C chilled group and control group (77.92 and 91.89%), but the survival rate of 15 and 10 °C chilled group were significantly decreased (46.34 and 4.81%, P < 0.01). A further experiment on15 °C group showed that most oocytes died from 2 to 4 h of IVM. In order to investigate the effects of chilling on oocytes at the subcellular level, the control and 15 °C chilled group COCs fixed at different time points of the IVM cultures (2, 2.5, 3, 3.5 and 4 h of IVM) were prepared for transmission electron microscope (TEM) observation. As the result, compared with the control group, there were two significant changes in the ultrastructural morphology of 15 °C treatment group: (1) dramatic reduction of heterogeneous lipid, (2) disorganized mitochondria–endoplasmic reticulum–lipid vesicles (M–E–L) combination. These results indicate that 15 °C is a critical chilling temperature for porcine GV stage oocyte and the alteration of cellular chemical composition and the destruction of M–E–L combination maybe responsible for chilling injury of porcine oocyte at this stage. 相似文献
54.
Gautier Koscielny Vincent Le Texier Chellappa Gopalakrishnan Vasudev Kumanduri Jean-Jack Riethoven Francesco Nardone Eleanor Stanley Christine Fallsehr Oliver Hofmann Meelis Kull Eoghan Harrington Stéphanie Boué Eduardo Eyras Mireya Plass Fabrice Lopez William Ritchie Virginie Moucadel Takeshi Ara Heike Pospisil Alexander Herrmann Daniel Gautheret 《Genomics》2009,93(3):213-220
55.
Qingran Kong Meiling Wu Yanjun Huan Li Zhang Haiyan Liu Gerelchimeg Bou Yibo Luo Yanshuang Mu Zhonghua Liu 《PloS one》2009,4(8)
Transgenic animals have been used for years to study gene function, produce important proteins, and generate models for the study of human diseases. However, inheritance and expression instability of the transgene in transgenic animals is a major limitation. Copy number and promoter methylation are known to regulate gene expression, but no report has systematically examined their effect on transgene expression. In the study, we generated two transgenic pigs by somatic cell nuclear transfer (SCNT) that express green fluorescent protein (GFP) driven by cytomegalovirus (CMV). Absolute quantitative real-time PCR and bisulfite sequencing were performed to determine transgene copy number and promoter methylation level. The correlation of transgene expression with copy number and promoter methylation was analyzed in individual development, fibroblast cells, various tissues, and offspring of the transgenic pigs. Our results demonstrate that transgene expression is associated with copy number and CMV promoter methylation in transgenic pigs. 相似文献
56.
A modified Segmental Sedimentation and Counting Technique (SSCT) to examine the presence of Echinococcus multilocularis helminths in segments of fox (Vulpes vulpes) intestine is described and compared to the “gold standard”, SCT. Out of the 358 intestines collected, 117 were E. multilocularis positive. Using SSCT methods we compare the sensitivity of individual or pairs of segments to establish a tradeoff between saving time and the reliability of the diagnosis, especially in areas with low infection intensities. The results show that the analysis of segment S4 associated with segment S1 or S2 give 98.3% sensitivity, with specificity close to 100%. Based on our results and the time saved, we recommend using SSCT for routine examination of fox intestines for large epidemiological studies, particularly where the endemic prevalence of E. multilocularis is low or unknown. 相似文献
57.
We cloned the cDNA and genomic DNA encoding for Izumo1 of cashmere goat (Capra hircus) and sheep (Ovis aries). Analysis of 4.6 kb Izumo1 genomic sequences in sheep and goat revealed a canonical open reading frame (ORF) of 963 bp spliced
by eight exons. Sheep and goat Izumo1 genes share >99% identity at both DNA and protein levels and are also highly homologous to the orthologues in cattle, mouse,
rat and human. Extensive cloning and analysis of Izumo1 cDNA revealed three (del 69, del 182 and del 217) and two (del 69
and ins 30) alternative splicing isoforms in goat and sheep, respectively. All of the isoforms are derived from splicing at
typical GT-AG sites leading to partial or complete truncation of the immunoglobulin (Ig)-like domain. Bioinformatics analysis
showed that caprine and ovine Izumo1 proteins share similar structure with their murine orthologue. There are a signal peptide
at the N-terminus (1–22 aa), a transmembrane domain at the C-terminus (302–319 aa), and an extracellular Ig-like region in
the middle (161–252 aa) with a putative N-linked glycosylation site (N205-N-S). Alignment of Izumo1 protein sequences among 15 mammalian species displayed several highly conserved regions, including
LDC and YRC motifs with cysteine residues for potential disulfide bridge formation, CPNKCG motif upstream of the Ig-like domain,
GLTDYSFYRVW motif upstream of the putative N-linked glycosylation site, and a number of scattered cysteine residues. These
distinctive features are very informative to pinpoint the important gene motifs and functions. The C-terminal regions, however,
are more variable across species. Izumo1 cDNA sequences of goat, sheep, and cow were found to be largely homologous, and the
molecular phylogenetic analysis is consistent with their morphological taxonomy. This implies the Izumo1 gene evolves from the same ancestor, and the mechanism of sperm–egg fusion in mammals may be under the same principle in
which Izumo1 plays an important role. 相似文献
58.
Farah Abdel Samad Alex Baumel Marianick Juin Daniel Pavon Sonia Siljak-Yakovlev Frédéric Médail Magda Bou Dagher Kharrat 《Plant Systematics and Evolution》2014,300(5):819-830
The Lebanese mountain range is an important zone of plant species richness and endemism where the genus Astragalus constitutes a principal component of plant biodiversity. Most of endemic Astragalus taxa, living in mountains and arid zones of Mounts Lebanon and anti-Lebanon, are characterized by a cushion, spiny vegetative form, named “tragacanthic”, which is a remarkable example of vegetative convergence evolution. Because of determination difficulties, taxonomic uncertainties, and discrepancy in the number of taxa listed according to authors, new data are hardly needed to improve systematics of Astragalus and to investigate the role of the Lebanese mountain range as refugia of biodiversity. Before this study only two values on the genome size of Astragalus were reported in the literature and no previous molecular studies had been carried out on Astragalus genus in Lebanon. We examined the utility of rDNA ITS molecular markers to distinguish Astragalus species of Lebanese mountain range and the variation range of their genome size. The main results revealed a striking diversity in Lebanese Astragalus species with the emphasis of a huge variation of genome sizes, an important inter-specific chromosome polymorphism and the existence of a high phylogenetic diversity. The strict endemic species of the Lebanese mountains are positioned throughout the phylogeny. These results confirm that the Lebanon and anti-Lebanon mounts constitute a third diversity center for Astragalus and that high altitude areas are important refugia of plant biodiversity despite centuries of exploitation by humans. 相似文献
59.
Kabindra Adhikari Alfred E. Hartemink Budiman Minasny Rania Bou Kheir Mette B. Greve Mogens H. Greve 《PloS one》2014,9(8)
Estimation of carbon contents and stocks are important for carbon sequestration, greenhouse gas emissions and national carbon balance inventories. For Denmark, we modeled the vertical distribution of soil organic carbon (SOC) and bulk density, and mapped its spatial distribution at five standard soil depth intervals (0−5, 5−15, 15−30, 30−60 and 60−100 cm) using 18 environmental variables as predictors. SOC distribution was influenced by precipitation, land use, soil type, wetland, elevation, wetness index, and multi-resolution index of valley bottom flatness. The highest average SOC content of 20 g kg−1 was reported for 0−5 cm soil, whereas there was on average 2.2 g SOC kg−1 at 60−100 cm depth. For SOC and bulk density prediction precision decreased with soil depth, and a standard error of 2.8 g kg−1 was found at 60−100 cm soil depth. Average SOC stock for 0−30 cm was 72 t ha−1 and in the top 1 m there was 120 t SOC ha−1. In total, the soils stored approximately 570 Tg C within the top 1 m. The soils under agriculture had the highest amount of carbon (444 Tg) followed by forest and semi-natural vegetation that contributed 11% of the total SOC stock. More than 60% of the total SOC stock was present in Podzols and Luvisols. Compared to previous estimates, our approach is more reliable as we adopted a robust quantification technique and mapped the spatial distribution of SOC stock and prediction uncertainty. The estimation was validated using common statistical indices and the data and high-resolution maps could be used for future soil carbon assessment and inventories. 相似文献
60.
Patrice?Njomnang?Soh Boris?Delaunay Elie?Bou?Nasr Martine?Delannes Michel?Soulie Eric?HuygheEmail author 《Andrologie》2014,24(1):13