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排序方式: 共有436条查询结果,搜索用时 15 毫秒
91.
Caecal microbiota could effectively increase chicken growth performance by regulating fat metabolism
Xiaolong Zhang Yafang Hu Abdur Rahman Ansari Muhammad Akhtar Yan Chen Ranran Cheng Lei Cui Abdallah A. Nafady Abdelmotaleb A. Elokil El-Sayed M. Abdel-Kafy Huazhen Liu 《Microbial biotechnology》2022,15(3):844-861
It has been established that gut microbiota influences chicken growth performance and fat metabolism. However, whether gut microbiota affects chicken growth performance by regulating fat metabolism remains unclear. Therefore, seven-week-old chickens with high or low body weight were used in the present study. There were significant differences in body weight, breast and leg muscle indices, and cross-sectional area of muscle cells, suggesting different growth performance. The relative abundance of gut microbiota in the caecal contents at the genus level was compared by 16S rRNA gene sequencing. The results of LEfSe indicated that high body weight chickens contained Microbacterium and Sphingomonas more abundantly (P < 0.05). In contrast, low body weight chickens contained Slackia more abundantly (P < 0.05). The results of H & E, qPCR, IHC, WB and blood analysis suggested significantly different fat metabolism level in serum, liver, abdominal adipose, breast and leg muscles between high and low body weight chickens. Spearman correlation analysis revealed that fat metabolism positively correlated with the relative abundance of Microbacterium and Sphingomonas while negatively correlated with the abundance of Slackia. Furthermore, faecal microbiota transplantation was performed, which verified that transferring faecal microbiota from adult chickens with high body weight into one-day-old chickens improved growth performance and fat metabolism in liver by remodelling the gut microbiota. Overall, these results suggested that gut microbiota could affect chicken growth performance by regulating fat metabolism. 相似文献
92.
Casteleijn MG Alahuhta M Groebel K El-Sayed I Augustyns K Lambeir AM Neubauer P Wierenga RK 《Biochemistry》2006,45(51):15483-15494
The importance of the fully conserved active site proline, Pro168, for the reaction mechanism of triosephosphate isomerase (TIM) has been investigated by studying the enzymatic and crystallographic properties of the P168A variant of trypanosomal TIM. In TIM, Pro168 follows the key catalytic residue Glu167, situated at the beginning of the flexible active site loop (loop 6). Turnover numbers of the P168A variant for its substrates are reduced approximately 50-fold, whereas the Km values are approximately 2 times lower. The affinity of the P168A variant for the transition state analogue 2-phosphoglycolate (2PG) is reduced 5-fold. The crystal structures of unliganded and liganded (2PG) P168A show that the phosphate moiety of 2PG is bound similarly as in wild-type TIM, whereas the interactions of the carboxylic acid moiety with the side chain of the catalytic Glu167 differ. The unique properties of the proline side chain at position 168 are required to transmit ligand binding to the conformational change of Glu167: the side chain of Glu167 flips from the inactive swung-out to the active swung-in conformation on ligand binding in wild-type TIM, whereas in the mutant this conformational change does not occur. Further structural comparisons show that in the wild-type enzyme the concerted movement of loop 6 and loop 7 from unliganded-open to liganded-closed appears to be facilitated by the interactions of the phosphate moiety with loop 7. Apparently, the rotation of 90 degrees of the Gly211-Gly212 peptide plane of loop 7 plays a key role in this concerted movement. 相似文献
93.
94.
F. F. Abdel-Motaal M. S. M. Nassar S. A. El-Zayat M. A. El-Sayed S. Ito 《Folia microbiologica》2009,54(3):207-212
Antifungal activity of hyoscyamine (Hcy) and scopolamine (Sco) were determined by TLC-bioautography against fungi associated
with H. muticus grown in Egypt, and those isolated from other plants grown in Japan. All 40 fungal strains were tolerant to Sco and sensitive
to Hcy, exhibiting a growth inhibition zone around the Hcy spot on the bioautography plate. The strains were grouped into
three types based on the appearance of the inhibition zone: (i) 17 strains exhibiting a clear inhibition zone, which remained clear at 8 d after incubation (type I); (ii) 22 strains exhibiting the inhibition zone with a brown circle surrounding the zone and regrowth within the inhibition zone
(type II); (iii) 1 strain exhibiting the inhibition zone with no brown circle and regrowth within the inhibition zone (type III). In the type II and III strains, Hcy disappeared, and other alkaloids were found in the inhibition zones in its place. Hcy feeding experiments using
Penicillium purpurogenum (type II) and Cunninghamella elegans (type III) revealed that these fungi may convert Hcy to a new alkaloid compound. 相似文献
95.
Ashraf S. A. El-Sayed 《Indian journal of microbiology》2009,49(3):243-250
Solid state fermentation was conducted for the production of L-glutaminase by Trichoderma koningii Oud.aggr. using different agro-industrial byproducts inlcuding wheat bran, groundnut residues, rice hulls, soya bean meal,
corn steep, sesamum oil cake, cotton seed residues and lentil industrial residues as solid substrates. Wheat bran was the
best substrate for induction of L-glutaminase (12.1 U/mg protein) by T. koningii. The maximum productivity (23.2 U/mg protein) and yield (45.0 U/gds) of L-glutaminase by T. koningii occurred using wheat bran of 70% initial moisture content, initial pH 7.0, supplemented with D-glucose (1.0%) and L-glutamine
(2.0% w/v), inoculated with 3 ml of 6 day old fungal culture and incubated at 30°C for 7 days. After optimization, the productivity
of L-glutaminase by the solid cultures of T. koningii was increased by 2.2 fold regarding to the submerged culture. 相似文献
96.
Highly concentrated aqueous solutions of acrylamide (Am) were polymerized in presence of polyethylene glycol (PEG) using ammonium persulfate as initiator under different conditions including ammonium persulfate concentration (0.02–0.06 g/gAm) temperature (60–95 °C), Am/PEG400 ratio (1/1–1/5 g/g), PEG molecular weight (400–6000). At optimum reaction conditions a PEG 400/PAm adduct was prepared with a % total conversion of 99.7 in 2 min using ammonium persulfate (0.05 g/gAm), Am/PEG (1/2 g/g) at 70 °C. The structure of the adduct was confirmed by FT-IR spectra. The adduct was utilized as a finishing additive for cotton fabric in presence and absence of dimethyloldihydroxy ethylene urea (DMDHEU) by the bad – dry – cure method. In absence of DMDHEU, the adduct improves the fabric tensile strength, stiffness and oily stain release rating without affect the wettability along with decreasing the fabric resiliency compared to the blank sample. Inclusion DMDHEU the finishing bath (50 g/l) results in improving the fabric resiliency and stiffness as well as decreasing the strength, wettability and oily stain release compared to those of fabric treated with adduct in absence of DMDHEU. However, at an adduct concentration of 40 g/l and in presence of 50 g/l DMDHEU the fabric properties are in general, superior to those of blank fabric. 相似文献
97.
Monica M. Lins-de-Barros Ricardo P. Vieira Alexander M. Cardoso Vivian A. Monteiro Aline S. Turque Cynthia B. Silveira Rodolpho M. Albano Maysa M. Clementino Orlando B. Martins 《Microbial ecology》2010,59(3):523-532
Reef-building corals may be seen as holobiont organisms, presenting diverse associated microbial communities. Best known is
the symbiotic relationship with zooxanthellae, but Archaea, Bacteria, fungi, viruses, and algal plastids are also abundant.
Until now, there is little information concerning microbial communities associated with Brazilian corals. The present study
aims to describe the diversity of Archaea, Bacteria, and eukaryotic algal plastid communities associated with two sympatric
species, Siderastrea stellata and Mussismilia hispida, from Southeastern Brazil, using 16S rRNA gene libraries. Since corals present a high number of other associated invertebrates,
coral barcoding (COI) was performed to confirm the exclusive occurrence of coral DNA in our samples. Our analysis yielded
354 distinct microbial OTUs, represented mainly by novel phylotypes. Richness (Chao1 and ACE) and diversity (H') estimations
of the microbial communities associated with both species were high and comparable to other studies. Rarefaction analyses
showed that microbial diversity of S. stellata is higher than that of M. hispida. Libshuff comparative analyses showed that the highest microbial community similarity between the two coral species occurred
in the bacterial libraries, while archaeal and plastidial communities were significantly different. Crenarchaeota dominated
archaeal communities, while Proteobacteria was the most abundant bacterial phylum, dominated by alpha-Proteobacteria. Plastids
were also represented by novel phylotypes and did not match with any 16S rRNA sequences of Cyanobacteria and zooxanthellae
from GenBank. Our data improves the pool of available information on Brazilian coral microbes and shows corals as sources
of diverse prokaryotic and picoeukaryotic communities. 相似文献
98.
Fatmah A.M. Al-Omary Laila A. Abou-zeid Mahmoud N. Nagi El-Sayed E. Habib Alaa A.-M. Abdel-Aziz Adel S. El-Azab Sami G. Abdel-Hamide Mohamed A. Al-Omar Abdulrahman M. Al-Obaid Hussein I. El-Subbagh 《Bioorganic & medicinal chemistry》2010,18(8):2849-2863
A new series of 2,6-substituted-quinazolin-4-ones was designed, synthesized, and evaluated for their in vitro DHFR inhibition, antimicrobial, and antitumor activities. Compounds 22, 33–37, 39–43, and 45 proved to be active DHFR inhibitors with IC50 range of 0.4–1.0 μM. Compound 18 showed broad-spectrum antimicrobial activity comparable to the known antibiotic gentamicin. Compounds 34 and 36 showed antitumor activity at GI50 (MG-MID) concentrations of 11.2, and 24.2 μM, respectively. Molecular modeling study including flexible alignment; electrostatic, hydrophobic mappings; and pharmacophore prediction were performed. A main featured pharmacophore model was developed which justifies the importance of the main pharmacophoric groups as well as of their relative distances. The substitution pattern and spatial considerations of the π-systems in regard to the quinazoline nucleus proved critical for biological activity. 相似文献
99.
Maysa Faisal Suyagh Jeff Millership Paul Collier Henry Halliday James C. McElnay 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(9-10):769-776
A selective and sensitive liquid chromatography (LC)–atmospheric pressure chemical ionisation (APCI)–mass spectroscopic (MS) assay of canrenone has been developed and validated employing Dried Blood Spots (DBS) as the sample collection medium. DBS samples were prepared by applying 30 μl of spiked whole blood onto Guthrie cards. A 6 mm disc was punched from the each DBS and extracted with 2 ml of methanolic solution of 17α-methyltestosterone (Internal Standard). The methanolic extract was evaporated to dryness and reconstituted in acetonitrile:water (1:9, v/v). The reconstituted solution was further subjected to solid phase extraction using HLB cartridges. Chromatographic separation was achieved using Waters Sunfire C18 reversed-phase column using isocratic elution, followed by a high organic wash to clear late eluting/highly retained components. The mobile phase consisted of methanol:water (60:40, v/v) pumped at a flow rate of 0.3 ml/min. LC–APCI–MS detection was performed in the selected-ion monitoring (SIM) mode using target ions at m/z 341.1 and 303.3 for canrenone and internal standard respectively. The selectivity of the method was established by analysing DBS samples from 6 different sources (individuals). The calibration curve for canrenone was found to be linear over 25–1000 ng/ml (r > 0.994). Accuracy (% RE) and precision (% CV) values for within and between day were <20% at the lower limit of quantification (LLQC) and <15% at all other concentrations tested. The LLOQ of the method was validated at 25 ng/ml. Clinical validation of the method was achieved by employing the validated method for analysis of 160 DBS samples from 37 neonatal and paediatric patients. 相似文献
100.
Amal A. Sallam Yukio Hitotsuyanagi El-Sayed S. Mansour Atallah F. Ahmed Sahar Gedara Haruhiko Fukaya Koichi Takeya 《Phytochemistry letters》2010,3(3):117-121
From the roots of Bryonia cretica L. two new cucurbitacins, isocucurbitacins G (1) and H (2), along with three known cucrbitacins, cucurbitacins G (3), H (4), and J (5) were isolated. The structures of 1 and 2 were determined on the basis of 1D and 2D NMR spectroscopic analysis and X-ray crystallography. The relative stereochemistries of the side chains of 3–5 were also established by comparison of their NMR data and X-ray crystallography. 相似文献