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81.
Ellen Schulz Vanessa Piotrowski Marcus Clauss Marcus Mau Gildas Merceron Thomas M. Kaiser 《PloS one》2013,8(2)
Dental microwear and 3D surface texture analyses are useful in reconstructing herbivore diets, with scratches usually interpreted as indicators of grass dominated diets and pits as indicators of browse. We conducted feeding experiments with four groups of rabbits (Oryctolagus cuniculus) each fed a different uniform, pelleted diet (lucerne, lucerne & oats, grass & oats, grass). The lowest silica content was measured in the lucerne and the highest in the grass diet. After 25 weeks of exposure to the diets, dental castings were made of the rabbit''s lower molars. Occlusal surfaces were then investigated using dental microwear and 3D areal surface texture analysis. In terms of traditional microwear, we found our hypothesis supported, as the grass group showed a high proportion of (long) “scratches” and the lucerne group a high proportion of “pits”. Regardless of the uniform diets, variability of microwear and surface textures was higher when silica content was low. A high variability in microwear and texture analysis thus need not represent dietary diversity, but can also be related to a uniform, low-abrasion diet. The uniformity or variability of microwear/texture analysis results thus might represent varying degrees of abrasion and attrition rather than a variety of diet items per se. 相似文献
82.
Hamadryas baboons possess salivary proline-rich proteins (PRP), as indicated by the presence of pink-staining protein bands using 1D SDS gel electrophoresis and Coomassie R250 staining. The ability of these protein bands to interact with tannic acid was further examined. In a tannin-binding assay using 5 μg tannic acid mixed with hamadryas whole saliva, we recently found four distinct protein bands of apparently 72, 55, 20, and 15 kDa that were precipitated during the experiments. In this work, we were able to identify these protein bands in a follow-up analysis using MS/MS mass spectrometry after excising such bands out of air-dried gels. Albumin and α-amylase were present in the tannic acid-protein complexes, with albumin already known to nonspecifically interact with a great diversity of chemical compounds. More interesting, we also identified a basic PRP and a cystatin precursor protein. This was the first successful attempt to identify a PRP from precipitated tannin-protein complexes in hamadryas baboons using MS/MS mass spectrometry. On the other hand, the role of cystatins in tannin binding is not yet well understood. However, there are recent reports on cystatin expression in saliva of rats responding to astringent dietary compounds. In conclusion, the follow-up data on tannin-binding proteins present in salivary secretions from hamadryas baboons adds important knowledge to primate physiology and feeding ecology, in order to shed light on the establishment and development of food adaptations in primates. It also demonstrates that tannin binding is characteristic for PRP, but might not be restricted to this particular group of proteins in primate species. 相似文献
83.
Glasner JD Yang CH Reverchon S Hugouvieux-Cotte-Pattat N Condemine G Bohin JP Van Gijsegem F Yang S Franza T Expert D Plunkett G San Francisco MJ Charkowski AO Py B Bell K Rauscher L Rodriguez-Palenzuela P Toussaint A Holeva MC He SY Douet V Boccara M Blanco C Toth I Anderson BD Biehl BS Mau B Flynn SM Barras F Lindeberg M Birch PR Tsuyumu S Shi X Hibbing M Yap MN Carpentier M Dassa E Umehara M Kim JF Rusch M Soni P Mayhew GF Fouts DE Gill SR Blattner FR Keen NT Perna NT 《Journal of bacteriology》2011,193(8):2076-2077
Dickeya dadantii is a plant-pathogenic enterobacterium responsible for the soft rot disease of many plants of economic importance. We present here the sequence of strain 3937, a strain widely used as a model system for research on the molecular biology and pathogenicity of this group of bacteria. 相似文献
84.
The allelopathic activity of the aquatic macrophyte, Stratiotes aloides, was determined with laboratory experiments. Active compounds exuded in the medium or present in plant tissue were extracted
using standard procedures and solid phase extraction (SPE). The activity towards various cyanobacteria and chlorophytes was
tested in two different bioassay systems using agar plates and liquid cultures of phytoplankton. Extracts and exudates of
S. aloides affected phytoplankton growth. SPE-enriched exudates and enriched water from a natural Stratiotes stand caused inhibition of target species, however, also some controls were active. Phytoplankton species exhibited differential
sensitivity to extracts of S. aloides. We observed inhibitory and stimulatory effects on phytoplankton. In general, more cyanobacteria than other phytoplankton
species were inhibited, and the inhibition of cyanobacteria was stronger. In most cases, nutrient (P or K) limitation of Synechococcus elongatus and Scenedesmus obliquus decreased the sensitivity of these species towards allelochemicals from Stratiotes aloides, except for P-limited cultures of Scenedesmus. The allelopathically active compound(s) from Stratiotes are moderately lipophilic and most likely no phenolic compounds. Our results indicate that allelopathy (besides nutrient
interference and shading) might also account for the low phytoplankton and filamentous algae densities in the vicinity of
Stratiotes plants, at least during certain phases of the life-cycle of Stratiotes. 相似文献
85.
86.
Nguyen Thi Ngoc Lan Hoang Thi Thu Hoan Nguyen Huu Quan Tu Quang Tan Tran Thi Hong Lo Thi Mai Thu Vu Thi Thu Thuy Chu Hoang Mau 《In vitro cellular & developmental biology. Plant》2022,58(1):93-102
In Vitro Cellular & Developmental Biology - Plant - Aconitum carmichaelii Debx. is a medicinal plant that contains a variety of valuable medicinal substances, including flavonoids, alkaloids,... 相似文献
87.
Chai YY Rahman RN Illias RM Goh KM 《Journal of industrial microbiology & biotechnology》2012,39(5):731-741
Two genes that encode α-amylases from two Anoxybacillus species were cloned and expressed in Escherichia coli. The genes are 1,518 bp long and encode 506 amino acids. Both sequences are 98% similar but are distinct from other well-known
α-amylases. Both of the recombinant enzymes, ASKA and ADTA, were purified using an α-CD–Sepharose column. They exhibited an
optimum activity at 60°C and pH 8. Both amylases were stable at pH 6–10. At 60°C in the absence of Ca2+, negligible reduction in activity for up to 48 h was observed. The activity half-life at 65°C was 48 and 3 h for ASKA and
ADTA, respectively. In the presence of Ca2+ ions, both amylases were highly stable for at least 48 h and had less than a 10% decrease in activity at 70°C. Both enzymes
exhibited similar end-product profiles, and the predominant yield was maltose (69%) from starch hydrolysis. To the best of
our knowledge, most α-amylases that produce high levels of maltose are active at an acidic to neutral pH. This is the first
report of two thermostable, alkalitolerant recombinant α-amylases from Anoxybacillus that produce high levels of maltose and have an atypical protein sequence compared with known α-amylases. 相似文献
88.
Kushwaha GS Pandey N Sinha M Singh SB Kaur P Sharma S Singh TP 《Biochimica et biophysica acta》2012,1824(4):679-691
The ribosome inactivating proteins (RIPs) of type 1 are plant toxins that eliminate adenine base selectively from the single stranded loop of rRNA. We report six crystal structures, type 1 RIP from Momordica balsamina (A), three in complexed states with ribose (B), guanine (C) and adenine (D) and two structures of MbRIP-1 when crystallized with adenosine triphosphate (ATP) (E) and 2'-deoxyadenosine triphosphate (2'-dATP) (F). These were determined at 1.67?, 1.60?, 2.20?, 1.70?, 2.07? and 1.90? resolutions respectively. The structures contained, (A) unbound protein molecule, (B) one protein molecule and one ribose sugar, (C) one protein molecule and one guanine base, (D) one protein molecule and one adenine base, (E) one protein molecule and one ATP-product adenine molecule and (F) one protein molecule and one 2'-dATP-product adenine molecule. Three distinct conformations of the side chain of Tyr70 were observed with (i) χ(1)=-66°and χ(2)=165° in structures (A) and (B); (ii) χ(1)=-95° and χ(2)=70° in structures (C), (D) and (E); and (iii) χ(1)=-163° and χ(2)=87° in structure (F). The conformation of Tyr70 in (F) corresponds to the structure of a conformational intermediate. This is the first structure which demonstrates that the slow conversion of DNA substrates by RIPs can be trapped during crystallization. 相似文献
89.
Gajraj Singh KushwahaNisha Pandey Mau SinhaS. Baskar Singh Punit KaurSujata Sharma Tej P. Singh 《Biochimica et Biophysica Acta - Proteins and Proteomics》2012,1824(4):679-691
The ribosome inactivating proteins (RIPs) of type 1 are plant toxins that eliminate adenine base selectively from the single stranded loop of rRNA. We report six crystal structures, type 1 RIP from Momordica balsamina (A), three in complexed states with ribose (B), guanine (C) and adenine (D) and two structures of MbRIP-1 when crystallized with adenosine triphosphate (ATP) (E) and 2′-deoxyadenosine triphosphate (2′-dATP) (F). These were determined at 1.67 Å, 1.60 Å, 2.20 Å, 1.70 Å, 2.07 Å and 1.90 Å resolutions respectively. The structures contained, (A) unbound protein molecule, (B) one protein molecule and one ribose sugar, (C) one protein molecule and one guanine base, (D) one protein molecule and one adenine base, (E) one protein molecule and one ATP-product adenine molecule and (F) one protein molecule and one 2′-dATP-product adenine molecule. Three distinct conformations of the side chain of Tyr70 were observed with (i) χ1 = − 66°and χ2 = 165° in structures (A) and (B); (ii) χ1 = − 95° and χ2 = 70° in structures (C), (D) and (E); and (iii) χ1 = − 163° and χ2 = 87° in structure (F). The conformation of Tyr70 in (F) corresponds to the structure of a conformational intermediate. This is the first structure which demonstrates that the slow conversion of DNA substrates by RIPs can be trapped during crystallization. 相似文献
90.
Sharma P Singh N Sinha M Sharma S Perbandt M Betzel C Kaur P Srinivasan A Singh TP 《Journal of molecular biology》2008,378(4):923-932
The mammalian peptidoglycan recognition protein-S (PGRP-S) binds to peptidoglycans (PGNs), which are essential components of the cell wall of bacteria. The protein was isolated from the samples of milk obtained from camels with mastitis and purified to homogeneity and crystallized. The crystals belong to orthorhombic space group I222 with a = 87.0 Å, b = 101.7 Å and c = 162.3 Å having four crystallographically independent molecules in the asymmetric unit. The structure has been determined using X-ray crystallographic data and refined to 1.8 Å resolution. Overall, the structures of all the four crystallographically independent molecules are identical. The folding of PGRP-S consists of a central β-sheet with five β-strands, four parallel and one antiparallel, and three α-helices. This protein fold provides two functional sites. The first of these is the PGN-binding site, located on the groove that opens on the surface in the direction opposite to the location of the N terminus. The second site is implicated to be involved in the binding of non-PGN molecules, it also includes putative N-terminal segment residues (1-31) and helix α2 in the extended binding. The structure reveals a novel arrangement of PGRP-S molecules in which two pairs of molecules associate to form two independent dimers. The first dimer is formed by two molecules with N-terminal segments at the interface in which non-PGN binding sites are buried completely, whereas the PGN-binding sites of two participating molecules are fully exposed at the opposite ends of the dimer. In the second dimer, PGN-binding sites are buried at the interface while non-PGN binding sites are fully exposed at the opposite ends of the dimer. This form of dimeric arrangement is unique and seems to be aimed at enhancing the capability of the protein against specific invading bacteria. This mode of functional dimerization enhances efficiency and specificity, and is observed for the first time in the family of PGRP molecules. 相似文献