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91.
Glycogen synthase kinase-3alpha (GSK-3alpha) was recently found to be an attractive target for the treatment of Alzheimer's disease due to its dual action in the formation of both amyloid plaques and neurofibrillary tangles. It is also a viable target for many other diseases, such as type 2 diabetes. Reported herein is a 2D-QSAR exploration of the physicochemical (hydrophobic, electronic, and steric) and structural requirements among 3-anilino-4-phenylmaleimides toward GSK-3alpha binding. Using Fujita-Ban and Hansch QSAR analysis, electronic and steric interactions at the 4-phenyl ring and hydrophobic interactions at the 3-anilino ring are shown to be crucial. Analysis of the 4-phenyl ring of these compounds using common aromatic substituent constants showed electron-withdrawing and bulky ortho substituents as imperative for GSK-3alpha inhibition. 相似文献
92.
93.
Keyur Raval Kartik Gehlot Prasanna B. D. 《Preparative biochemistry & biotechnology》2017,47(2):192-198
Naringinase bioprocess based on Bacillus methylotrophicus was successfully scaled up based on constant oxygen transfer rate (OTR) as the scale-up criterion from 5-L bioreactor to 20-L bioreactor. OTR was measured in 5 and 20-L bioreactor under various operating conditions using dynamic method. The operating conditions, where complete dispersion was observed were identified. The highest OTR of 0.035 and 0.04?mMol/L/s was observed in 5 and 20-L bioreactor, respectively. Critical dissolved oxygen concentration of novel isolated strain B. methylotrophicus was found to be 20% of oxygen saturation in optimized medium. The B. methylotrophicus cells grown on sucrose had maximum oxygen uptake rate of 0.14?mMol/L/s in optimized growth medium. The cells produced the maximum naringinase activity of 751 and 778?U/L at 34?hr in 5 and 20-L bioreactors, respectively. The maximum specific growth rate of about 0.178/hr was observed at both the scales of operations. The maximum naringinase yield of 160 and 164?U/g biomass was observed in 5 and 20-L bioreactors, respectively. The growth and production profiles at both scales were similar indicating successful scale-up strategy for B. methylotrophicus culture. 相似文献
94.
Ibne Ali Vikrant Singh Chouhan Satyaveer Singh Dangi Mahesh Gupta Ujjwala Tandiya Iqbal Hyder Vijay Pratap Yadav Rudra Prasanna Panda Vazhoor Babitha Vimla Nagar Arvind Sonwane Firdous Ahmad Khan Bikash Chandra Das Gyanendra Singh Sadhan Bag Mihir Sarkar 《Theriogenology》2014
Recent experiments using expression, immunolocalization, and cell culture approaches have provided leading insights into regulation of luteal angiogenesis by different growth factor systems and its role in the function of corpus luteum (CL) in buffalo. On the contrary, lymphangiogenesis and its regulation in the CL are still poorly understood. The aim of this study was to evaluate the expression and localization of lymphangiogenic factors (vascular endothelial growth factor [VEGF]-C and VEGFD), their receptor (VEGFR3), and lymphatic endothelial marker (LYVE1) in bubaline CL during different stages of the estrous cycle and to investigate functional role of VEGFC and VEGFD in luteal lymphangeogenesis. The mRNA and protein expression of VEGFC, VEGFD, and VEGFR3 was significantly greater in mid and late luteal phases, which correlated well with the expression of LYVE1. The lymphangiogenic factors were localized in luteal cells, exclusively in the cytoplasm. Immunoreactivity of VEGFC was greater during midluteal phase and that of VEGFD was greater during the mid and late luteal phases. Luteal cells were cultured in vitro and treated for different time duration (24, 48, and 72 hours) with VEGFC and VEGFD each at 50, 100, and 150 ng/mL concentration and VEGFC with VEGFD at 100 ng/mL concentration. The temporal increase in LYVE1 mRNA expression was significant (P < 0.05) in VEGFC and VEGFC with VEGFD treatment and no significant change was seen in VEGFD treatment. Thus, it seems likely that VEGFD itself has little role in lymphangiogenesis but along with VEGFC it might have a synergistic effect on VEGFR3 receptors for inducing lymphangiogenesis. In summary, the present study provided evidence that VEGFC and VEGFD, and their receptor VEGFR3, are expressed in bubaline CL and are localized exclusively in the cell cytoplasm, suggesting that these factors have a functional role in lymphangiogenesis of CL in buffalo. 相似文献
95.
Bobyk KD Kim SG Kumar VP Kim SK West AH Cook PF 《Archives of biochemistry and biophysics》2011,(2):71-80
Saccharopine dehydrogenase catalyzes the NAD-dependent conversion of saccharopine to generate l-lysine and α-ketoglutarate. A disulfide bond between cysteine 205 and cysteine 249, in the vicinity of the dinucleotide-binding site, is observed in structures of the apoenzyme, while a dithiol is observed in a structure with AMP bound, suggesting preferential binding of the dinucleotide to reduced enzyme. Mutation of C205 to S gave increased values of V/Et and V/KEt at pH 7 compared to wild type. Primary deuterium and solvent deuterium kinetic isotope effects suggest the catalytic pathway, which includes the hydride transfer and hydrolysis steps, contributes more to rate limitation in C205S, but the rates of the two steps relative to one another remain the same. There is a large increase in the rate constants V1/Et and V1/KNADEt at pH values below 7 compared to WT. Data indicate the low pH increase in activity results from a decreased sensitivity of the C205S mutant enzyme to the protonation state of an enzyme group with a pKa of about 7, likely responsible for a pH-dependent conformational change. Reduction of WT and C205S mutant enzymes with TCEP gives equal activities at pH 6, consistent with the increased activity observed for the C205S mutant enzyme. 相似文献
96.
Microscopic investigations were undertaken to decipher the diversity in the lotic algal communities from acidic waters (pH 2.4–3.2)
flowing overland in sheets and channels at an acid mine drainage (AMD) barrens near Kylertown, PA, USA. Microscopic observations,
supplemented with taxonomic keys, aided in identification of the dominant algae, and measurement of carbon from adjacent soils
was undertaken. The unicellular protist Euglena sp. was most abundant in slower flowing waters (i.e., pool near point of emergence and surficial flow sheets), while Ulothrix sp. was most abundant in faster flowing water from the central stream channel. A diverse range of unicellular microalgae
such as Chlorella, Cylindrocystis, Botryococcus, and Navicula and several filamentous forms identified as Microspora, Cladophora, and Binuclearia were also recorded. The observed high algal diversity may be related to the long duration of AMD flow at this site which
has led to the development of adapted algal communities. The comparatively higher carbon content in soil materials adjacent
to slower flowing water sampling locations provides evidence for the important role of algae as primary producers in this
extreme environment. 相似文献
97.
The ability of cyanobacteria to be useful as matrices for agriculturally important bacteria was evaluated. Biofilms were generated
with the selected strain Anabaena torulosa after co-culturing with Azotobacter chroococcum, Pseudomonas striata, Serratia marcescens, and Mesorhizobium ciceri. The biochemical attributes were compared with individual bacterial and cyanobacterial cultures. The biofilms were characterized
in terms of proteins, chlorophyll, IAA production, acetylene-reducing activity, phosphate solubilization, and antagonism towards
selected phytopathogenic fungi. An enhancement in the population counts was recorded in A. torulosa–S. marcescens and A. torulosa–P. striata biofilms. The A. torulosa–A. chroococcum and A. torulosa–M. ciceri biofilms were also able to utilize new saccharides as compared to the individual cultures. Such novel biofilms with agriculturally
useful traits can provide additional advantages including the broader spectrum of activity and the presence or formation of
biologically active compounds; they also suggest the way to effective inoculants for sustainable and environment friendly
agriculture. 相似文献
98.
K.?Murugan Jiang-Shiou?HwangEmail author K.?Kovendan K.?Prasanna Kumar C.?Vasugi A.?Naresh Kumar 《Hydrobiologia》2011,666(1):331-338
The efficacy of plant extracts (neem tree, Azadirachta indica A. Juss.; Meliaceae) and copepods [Mesocyclops aspericornis (Daday)] for the control of the dengue vector Aedes aegypti L. was tested in the laboratory. Neem Seed Kernel Extract (NSKE) at 25, 50, 100, 200 and 400 ppm caused significant mortality
of Ae. aegypti larvae. Lethal concentrations (LC50 and LC90) were worked out. The LC50 and LC90 values for I to IV larval instars were 111.98, 138.34, 158.93, 185.22 ppm and for pupae was 146.13 ppm, respectively. The
LC90 value of I instar was 372.95 ppm, II instar was 422.77 ppm, III instar was 440.63 ppm, IV instar was 456.96 ppm, and pupae
was 476.92 ppm, respectively. A study was conducted to test the whether the predatory efficiency of copepods on first instars
changed in the presence of NSKE. The percentage of predatory efficiency of copepod was 6.80% in treatments without NSKE and
the percentage of predatory efficiency increased up to 8.40% when copepods were combined with NSKE. This increase in predation
efficiency may caused by detrimental effects of the neem active principle compound (Azadirachtin) on the mosquito larvae.
Our results suggest that the combined application of copepods and neem extract to control Aedes populations is feasible. Repeated application of neem does not cause changes in copepod populations, because neem is highly
degradable in the environment. 相似文献
99.
Gene and QTL detection in a three-way barley cross under selection by a mixed model with kinship information using SNPs 总被引:1,自引:0,他引:1
Malosetti M van Eeuwijk FA Boer MP Casas AM Elía M Moralejo M Bhat PR Ramsay L Molina-Cano JL 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(8):1605-1616
Quantitative trait locus (QTL) detection is commonly performed by analysis of designed segregating populations derived from
two inbred parental lines, where absence of selection, mutation and genetic drift is assumed. Even for designed populations,
selection cannot always be avoided, with as consequence varying correlation between genotypes instead of uniform correlation.
Akin to linkage disequilibrium mapping, ignoring this type of genetic relatedness will increase the rate of false-positives.
In this paper, we advocate using mixed models including genetic relatedness, or ‘kinship’ information for QTL detection in
populations where selection forces operated. We demonstrate our case with a three-way barley cross, designed to segregate
for dwarfing, vernalization and spike morphology genes, in which selection occurred. The population of 161 inbred lines was
screened with 1,536 single nucleotide polymorphisms (SNPs), and used for gene and QTL detection. The coefficient of coancestry
matrix was estimated based on the SNPs and imposed to structure the distribution of random genotypic effects. The model incorporating
kinship, coancestry, information was consistently superior to the one without kinship (according to the Akaike information
criterion). We show, for three traits, that ignoring the coancestry information results in an unrealistically high number
of marker–trait associations, without providing clear conclusions about QTL locations. We used a number of widely recognized
dwarfing and vernalization genes known to segregate in the studied population as landmarks or references to assess the agreement
of the mapping results with a priori candidate gene expectations. Additional QTLs to the major genes were detected for all
traits as well. 相似文献
100.
The effect of dichloromethane (DCM) and ethyl acetate (EA) extract of a cyanobacterium, Microcystis aeruginosa was evaluated against unicellular cyanobacteria and the phytopathogenic fungus Rhizoctonia solani. Fractionation of the filtrate showed the presence of five spots of different Rf values on silica gel coated plates indicating
the presence of a number of compounds in the extract. A marked reduction in growth (52%) of the fungus was recorded on the
plates supplemented with cyanobacterial extract, indicating the involvement of anti-fungal metabolite(s). The extract did
not show any negative influence on seed germination and growth of seedlings of wheat, rice and mung, emphasizing the suitability
of the compound for use in agriculture. 相似文献