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111.
Anatol Luther Christian Bisang Daniel Obrecht 《Bioorganic & medicinal chemistry》2018,26(10):2850-2858
Macrocyclic peptide-based natural products have provided powerful new antibiotic drugs, drug candidates, and scaffolds for medicinal chemists as a source of inspiration to design novel antibiotics. While most of those natural products are active mainly against Gram-positive pathogens, novel macrocyclic peptide-based compounds have recently been described, which exhibit potent and specific activity against some of the most problematic Gram-negative ESKAPE pathogens. This mini-review gives an up-date on recent developments. 相似文献
112.
Bacillus probiotics: an alternative to antibiotics for livestock production 总被引:1,自引:0,他引:1 下载免费PDF全文
The use of probiotics as feed supplements in animal production has increased considerably over the last decade, particularly since the ban on antibiotic growth promoters in the livestock sector. Several Bacillus sp. are attractive for use as probiotic supplements in animal feed due to their ability to produce spores. Their heat stability and ability to survive the low pH of the gastric barrier represent an advantage over other probiotic micro‐organisms. This review discusses important characteristics required for selection of Bacillus probiotic strains and summarizes the beneficial effect of Bacillus‐based feed additives on animal production. Although the mechanism of action of Bacillus probiotics has not been fully elucidated, they are effective in improving the growth, survival and health status of terrestrial and aquatic livestock. Bacillus strains also have utility in bioremediation and can reduce nitrogenous waste, thereby improving environmental conditions and water quality. Finally, recent innovative approaches for using Bacillus spores in various applications are discussed. 相似文献
113.
Oral Antibiotic Treatment of Mice Exacerbates the Disease Severity of Multiple Flavivirus Infections
114.
Giorgia Letizia Marcone Elisa Binda Francesca Berini Flavia Marinelli 《Biotechnology advances》2018,36(2):534-554
Glycopeptide antibiotics are drugs of last resort for treating severe infections caused by multi-drug resistant Gram-positive pathogens. First-generation glycopeptides (vancomycin and teicoplanin) are produced by soil-dwelling actinomycetes. Second-generation glycopeptides (dalbavancin, oritavancin, and telavancin) are semi-synthetic derivatives of the progenitor natural products. Herein, we cover past and present biotechnological approaches for searching for and producing old and new glycopeptide antibiotics. We review the strategies adopted to increase microbial production (from classical strain improvement to rational genetic engineering), and the recent progress in genome mining, chemoenzymatic derivatization, and combinatorial biosynthesis for expanding glycopeptide chemical diversity and tackling the never-ceasing evolution of antibiotic resistance. 相似文献
115.
Morgane Sonia Thion Donovan Low Aymeric Silvin Jinmiao Chen Pauline Grisel Jonas Schulte-Schrepping Ronnie Blecher Thomas Ulas Paola Squarzoni Guillaume Hoeffel Fanny Coulpier Eleni Siopi Friederike Sophie David Claus Scholz Foo Shihui Josephine Lum Arlaine Anne Amoyo Anis Larbi Sonia Garel 《Cell》2018,172(3):500-516.e16
116.
Ohmori Takaaki Iwakawa Kazuhide Matsumoto Yasushi Arita Norimasa Okada Kazuyo 《Mycopathologia》1997,139(3):123-128
We report a fatal case of fungal (candidal) endocarditis of the tricuspid valve with clinico-pathologically interesting findings
following and associated with candidal pneumonia during long-term central venous catheterization (CVC) for intravenous therapy
and long-term treatment with antibiotics for bacterial and fungal infection in a patient with a history of alcohol abuse.
We review the literature on fungal cardiac infection related to long-term catheterization and alcohol abuse, and discuss the
pathogenesis.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
117.
118.
MARIA CRISTINA M. MOTTA LUIS HENRIQUE M. LEAL WANDERLEY DE SOUZA DARCY F. DE ALMEIDA LUIS CARLOS S. FERREIRA 《The Journal of eukaryotic microbiology》1997,44(5):492-496
ABSTRACT. Growth by serial transfers of the trypanosomatid Crithidia deanei in culture medium containing 1 mg/ml of the β-lactam antibiotics ampicillin or cephalexin resulted in shape distortion of its endosymbiont. The endosymbiont first appeared as filamentous structures with restricted areas of membrane damage. An increase of electron lucid areas was also observed in the endosymbiont matrix. The continuous treatment with β-lactam antibiotics, resulted in endosymbiont membranes fragmentation; and later on the space previously occupied by the symbiont was identified as an electron lucid area in the host cytoplasm. The putative targets of β-lactam antibiotic were two membrane-bound penicillin-binding proteins (PBPs) detected in the Sarkosyl-soluble fraction of purified symbionts labeled with [3 H]-benzylpenicillin. The apparent molecular weight of the proteins were 90 kDa (PBP1) and 45 kDa (PBP2). PBP2 represented 85% of the total PBP content in the membrane fraction of the endosymbionts. Competition experiments using the tested antibiotics and [3 H]-benzylpenicillin showed that ampicillin and cephalexin have half saturating concentrations considerably higher than [3 H]-benzylpenicillin and indicated that PBP1 is the probable lethal target of the antibiotics tested. These results suggest that a physiologically active PBP is present in the cell envelope of C. deanei endosymbionts and may play important roles in the control of processes such as cell division and shape determination. 相似文献
119.
The antiobiotics, diumycin, amphomycin, bacitracin, and showdomycin have been shown previously to block the synthesis of GlcNAc-P-P-dolichol and GlcNAc-GlcNAc-P-P-dolichol. In view of inconsistencies in the literature concerning the sites of inhibition, we have reinvestigated the influence of these drugs on the formation of these early intermediates of the dolichol pathway. Unexpectedly, when the individual products of the reactions were examined, instead of inhibition, showdomycin and bacitracin were found to stimulate the formation of GlcNAc-P-P-dolichol, and diumycin stimulated at low concentrations. Three derivatives of showdomycin were examined with similar results, showing stimulations of GlcNAc-P-P-dolichol formation of up to two-fold over controls. Amphomycin specifically inhibited GlcNAc-P-P-dolichol formation, an effect that was reversed by a high concentration of dolichyl phosphate. In contrast, with the exception of amphomycin, each compound directly inhibited the formation of GlcNAc-GlcNAc-P-P-dolichol. Using chemically synthesized GlcNAc-P-P-dolichol as substrate, the kinetics of inhibition of GlcNAc-GlcNAc-P-P-dolichol formation by showdomycin, bacitracin and diumycin was examined. The apparent Ki values calculated from these studies indicated that showdomycin was the most active inhibitor. These findings provide a new understanding of the action of these compounds on the GlcNAc-transferases of the dolichol pathway. © 1998 Rapid Science Ltd 相似文献
120.
Antibacterial activity of marine-derived fungi 总被引:4,自引:0,他引:4
Christophersen Carsten Crescente Oscar Frisvad Jens C. Gram Lone Nielsen Joan Nielsen Per Halfdan Rahbæk Lisa 《Mycopathologia》1998,143(3):135-138
A total of 227 marine isolates of ubiqituous fungi were cultivated on different media and the secondary metabolite content
of the extracts (ethyl acetate/chloroform/methanol 3 : 2 : 1) characterized by HPLC. The fungi were secured from animals,
plants and sediments of Venezuelan waters (0–10 m) including mangroves and lagoonal areas. The extracts were tested for antibacterial
activity. A total of 7 were active towards Vibrio parahaemolyticus and 55 towards Staphylococcus aureus, representing 18 different
fungal species from 8 ascomycetous genera. For 61 strains of Penicillium citrinum antibacterial activity correlated well with
content of secondary metabolites as measured by HPLC. Thirteen isolates of Penicillium steckii produced very similar profiles
of secondary metabolites and 6 of these had activity against either V. parahaemolyticus or S. aureus or both.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献