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991.
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Red cell carbonic anhydrase (Ca) types were investigated in 750 animals from three zebu, two exotic and three crossbred breeds. A Ca isozyme of slower mobility than the S isozyme was observed in four Sahiwal animals. The gene frequency of CaS, which was the predominant allele in all the breeds investigated ranged from 0.88 to 1.0. 相似文献
994.
Shashi Dhingra B. Bhatia G. S. Chhina Baldev Singh 《International journal of biometeorology》1987,31(3):191-199
Freezing incidence and tissue loss on exposure of hind limbs of female Wistar rats to freezing mixture was reduced by demedullation 6 days prior to cold exposure (p<0.01 and p<0.001 respectively); demedullation 1 h after freezing injury had no effect on tissue loss. Noradrenaline (1 mg/kg i.p.) 5 min before exposure increased the freezing incidence in intact (p<0.05) as well as in demedullated rats (p<0.01), with no effect on tissue loss. Adrenaline (500 mg/kg i.p.) had no effect on either. A sustained fall in plasma adrenaline after demedullation leading to reduced reactivity of the blood vessels to some vasoactive agents is postulated. 相似文献
995.
K K Kohli S C Bhatia T A Venkitasubramanian 《Environmental physiology & biochemistry》1975,5(2):119-125
The effect of a single oral dose of dieldrin (30 mg/kg body weight) on lipid metabolism in rats was studied. Liver lipids content increased and this increase was mainly in the triglyceride fraction. The incorporation of acetate-14C into fatty acids was decreased indicating an inhibition of lipogenesis. Fatty acid oxidation was increased. Palmitate-14C incorporation into the triglyceride fraction was enhanced pointing to an overall increased utilization of fatty acids. 相似文献
996.
997.
Development of chickpea EST-SSR markers and analysis of allelic variation across related species 总被引:1,自引:0,他引:1
Shalu Choudhary Niroj Kumar Sethy Bhumika Shokeen Sabhyata Bhatia 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(3):591-608
Despite chickpea being the third important grain legume, there is a limited availability of genomic resources, especially
of the expressed sequence tag (EST)-based markers. In this study, we generated 822 chickpea ESTs from immature seeds as well
as exploited 1,309 ESTs from the chickpea database, thus utilizing a total of 2,131 EST sequences for development of functional
EST-SSR markers. Two hundred and forty-six simple sequence repeat (SSR) motifs were identified from which 183 primer pairs
were designed and 60 validated as functional markers. Genetic diversity analysis across 30 chickpea accessions revealed ten
markers to be polymorphic producing a total of 29 alleles and an observed heterozygosity average of 0.16 thereby exhibiting
low levels of intra-specific polymorphism. However, the markers exhibited high cross-species transferability ranging from
68.3 to 96.6% across the six annual Cicer species and from 29.4 to 61.7% across the seven legume genera. Sequence analysis of size variant amplicons from various species
revealed that size polymorphism was due to multiple events such as copy number variation, point mutations and insertions/deletions
in the microsatellite repeat as well as in the flanking regions. Interestingly, a wide prevalence of crossability-group-specific
sequence variations were observed among Cicer species that were phylogenetically informative. The neighbor joining dendrogram clearly separated the chickpea cultivars
from the wild Cicer and validated the proximity of C. judaicum with C. pinnatifidum. Hence, this study for the first time provides an insight into the distribution of SSRs in the chickpea transcribed regions
and also demonstrates the development and utilization of genic-SSRs. In addition to proving their suitability for genetic
diversity analysis, their high rates of transferability also proved their potential for comparative genomic studies and for
following gene introgressions and evolution in wild species, which constitute the valuable secondary genepool in chickpea.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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We have identified two types of invertases, one bound ionically and the other covalently to the particulate fraction in grains
of heat tolerant C 306 and heat susceptible WH 542 cultivars of wheat (Triticum aestivum L.). The cell walls contained a high level of invertase activity, of which 79.2–72.8% was extractable by 2 M NaCl and 14.9–21.1%
by 0.5% EDTA in C 306 and WH 542, respectively. The NaCl-released invertase constituted the predominant fraction. Using 5–100 mM
sucrose and pH range of 4.0–7.0, the apparent Michaelis constant (K
m, enzyme substrate affinity measure) of enzyme ranged from 5.73 to 16.06 mM for C 306 and from 6.08 to 19.86 mM for WH 542.
The V
max (maximum catalytic rate) values at these pH were higher in C 306 (0.63–11.04 μg sucrose hydrolysed min−1) than WH 542 (0.51–8.73 μg sucrose hydrolysed min−1). By employing photo-oxidation and by studying the effect of pH on K
m and V
max, the involvement of histidine and α-carboxyl groups at the active site of the enzyme was indicated. The two cultivars also
showed differential response in terms of thermodynamic properties of the enzyme i.e. energy of activation (E
a), enthalpy change (ΔH) and entropy change (ΔS). NaCl-released invertase showed differential response to metal ions in two cultivars suggesting their distinctive nature.
Mn2+, Cu2+, Hg2+, Mg2+, Zn2+ and Cd2+ were strong inhibitors in WH 542 as compared to C 306 while K+, Ca2+ were stimulators in both the cultivars. Overall the results suggest that genetic differences exist in wall bound invertase
properties of wheat grains as evident in its altered kinetic behaviour. 相似文献