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991.
Effect of exercise on mRNA expression of select adrenal medullary catecholamine biosynthetic enzymes. 总被引:1,自引:0,他引:1
S Remzi Erdem Haydar A Demirel Christopher S Broxson Bistra B Nankova Esther L Sabban Nihal Tümer 《Journal of applied physiology》2002,93(2):463-468
The effect of submaximal endurance training (SET) on sympathoadrenal activity is not clear. We tested the hypothesis that SET (90 min/day, 5 days/wk, for 12 wk) elevates mRNA expression of catecholamine (CA) biosynthetic enzymes, tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DbetaH) in the adrenal medullae of adult, female Sprague-Dawley rats. SET increased TH protein level by 35%, TH activity by 62%, TH mRNA expression by 40%, and DbetaH mRNA expression by 67%. In addition, we examined the effect of SET on Fos-related antigens (FRAs), FRA-2 immunoreactivity, and activator protein (AP)-1 binding activity. SET increased AP-1 binding activity by 78%; however, it did not affect late FRAs and FRA-2 immunoreactivity. Because the regulation of neuropeptide Y (NPY) often parallels that of CAs, we also examined the effect of SET on NPY mRNA expression. Indeed, SET elevated NPY mRNA expression as well. We conclude that 1) SET elicits a pretranslational stimulatory effect on adrenomedullary CA biosynthetic enzymes, 2) another immediate early mRNA product, rather than FRA-2, may contribute to the increase in AP-1 binding activity in response to SET, and 3) SET increases NPY mRNA expression. 相似文献
992.
Eco-efficiency analysis by basf: the method 总被引:2,自引:0,他引:2
Peter Saling Andreas Kicherer Brigitte Dittrich-Krämer Rolf Wittlinger Winfried Zombik Isabell Schmidt Wolfgang Schrott Silke Schmidt 《The International Journal of Life Cycle Assessment》2002,7(4):203-218
Intention, Goal, Scope, Background BASF has developed the tool of eco-efficiency analysis to address not only strategic issues, but also issues posed by the
marketplace, politics and research. It was a goal to develop a tool for decision-making processes which is useful for a lot
of applications in chemistry and other industries. Objectives. The objectives were the development of a common tool, which
is usable in a simple way by LCA-experts and understandable by a lot of people without any experience in this field. The results
should be shown in such a way that complex studies are understandable in one view.
Methods The method belongs to the rules of ISO 14040 ff. Beyond these life cycle aspect costs, calculations are added and summarized
together with the ecological results to establish an eco-efficiency portfolio.
Results and Discussion The results of the studies are shown in a simple way, the eco-efficiency portfolio. Therefore, ecological data are summarized
in a special way as described in this paper. It could be shown that the weighting factors, which are used in our method, have
a negligible impact on the results. In most cases, the input data have an important impact on the results of the study. Conclusions.
It could be shown that the newly developed eco-efficiency analysis is a new tool, which is usable for a lot of problems in
decision-making processes. It is a tool which compares different alternatives of a defined customer benefit over the whole
life cycle.
Recommendations and Outlook This new method can be a helpful tool in different fields of the evaluation of product or process alternatives. It can be
used in research and development as well as in the optimization of customer processes and products. It is an analytical tool
for getting more sustainable processes and products in the future 相似文献
993.
Alfred E. Szmidt Marie‐Charlotte Nilsson Elmer Briceo Olle Zackrisson Xiao‐Ru Wang 《植被学杂志》2002,13(5):627-634
Abstract. In late successions of the boreal forest of northern Sweden the evergreen dwarf shrub Empetrum hermaphroditum forms an extensive cover and is believed to spread mainly vegetatively through layering. To analyse the process of population establishment and the relative importance of sexual vs asexual reproduction and the spatial clonal distribution of this species we selected one mainland and two island sites of different post‐fire successional ages (145, 375 and 1720 yr since last fire, respectively). Using 61 polymorphic RAPD markers, we found 96 genotypes in a total of 133 samples. All three populations showed high levels of genetic variation. AMOVA analysis revealed that 33% of the total variation resided among sites, 26% resided among plots within sites and 41% was due to variation within plots. The youngest population had only 14% clonal fraction. In contrast, the oldest population had > 30% clonal fraction and many genets had dimensions of 10–40 m and were intermingled. It appears that E. hermaphroditum establishes by seeds to a larger extent than previously thought and that the clonal spread by layering is rather slow. 相似文献
994.
SelÇuk Hazir Nevin Keskin S. Patricia Stock Harry K. Kaya Servet Özcan 《Biodiversity and Conservation》2003,12(2):375-386
The diversity and distribution of entomopathogenic nematodes in thefamilies Steinernematidae and Heterorhabditidae were assessed throughout anextensive soil survey in Turkey during 1999 and 2000. Entomopathogenic nematodeswere recovered from six out of seven regions sampled, with 22 positive sites(2%) out of 1080 sites sampled. A single nematode isolate was recovered at eachof the positive sites, of which 15 were steinernematid isolates and seven wereheterorhabditid isolates representing a total of four species. Based onmorphometric and molecular data, the nematode species were identified asHeterorhabditis bacteriophora, Steinernemafeltiae, S. affine, andSteinernema n. sp. The most common species was S.feltiae, which was isolated from 10 sites in six regions, followed byH. bacteriophora from seven sites in five regions,S. affine from four sites in two regions, andSteinernema n. sp. from one site. Heterorhabditisbacteriophora and S. feltiae have been found inmany parts of the world, whereas S. affine, so far, hasonly been recovered in Europe until our survey. Steinernemaaffine was isolated from the European (Marmara) as well as theAsiatic region (Middle Anatolia) of Turkey. A new undescribedSteinernema sp. was isolated from the most eastern region(East Anatolia) of Turkey. Soils of the positive sites were classified as sandy,sandy loam, or loam (68.2%) and sandy–clay–loam or clay loam (31.8%) and the pHranged from 5.6 to 7.9. The habitats from which the entomopathogenic nematodeswere isolated were broadly classified as disturbed (59.1%), which includedagricultural fields and poplar planted for lumber and wind breaks, andundisturbed (40.9%), which included pine forest, grassland, marsh and reed sites.Steinernema feltiae, S. affine, andH. bacteriophora were recovered from both disturbed andundisturbed habitats. The new Steinernema sp. was recoveredfrom grassland. Our survey showed that these nematodes occur widely throughoutTurkey, but at a frequency below that reported for other parts of the world. 相似文献
995.
Newly emerged females of the European pine sawfly, Neodiprion sertifer Geoffroy (Hymenoptera: Diprionidae), were placed on pine twigs in the field and their behavior was recorded. Twenty to 25% of the females attracted wild males and mated on the day of release. One-third to one-half of these females remained and oviposited, while the rest disappeared from their twigs after mating. The mating frequency peaked at noon, and on average the mating lasted for 19 ± 13 (SD) min. Eleven to 30% of the females that remained on their twigs after mating remated, occasionally up to five times. Most released females disappeared from their twigs on the first day. Disappearances included both predation and dispersal. Only a few dispersals >5 m were recorded, because the sawflies were difficult to follow during flight. By color marking, dispersal up to 20 m was recorded. 相似文献
996.
The tautomerism of uracil, 5-fluorouracil, and thymine has been investigated in the gas phase and in solution. Electron correlation effects were included in ab initio computations at the MP2 level, and DFT calculations were performed using the B3LYP level. Full geometry optimizations were conducted at the HF/6-31G**, HF/6-31+G**, and B3LYP/6-31+G** levels. Single-point MP2/6-31+G** calculations were performed on the HF/6-31+G** optimized geometries. The influence of the solvent was examined from self-consistent reaction field calculations performed with )=2.21 (1,4-dioxane) and )=78.54 (water). The calculated relative free energies ((G) indicate that substitution of uracil at the position group does not change the relative free energy order of the uracil tautomers in the gas phase and in 1,4-dioxane (except at the MP2 level) whereas this ordering changes in water. Attachment of a fluorine atom changes the relative free energy order of uracil tautomers in the gas phase and in solution. 相似文献
997.
Cloning and Expression of a Ralstonia eutropha HF39 Gene Mediating Indigo Formation in Escherichia coli 总被引:1,自引:0,他引:1 下载免费PDF全文
Sascha Drewlo Christian O. Brmer Mohamed Madkour Frank Mayer Alexander Steinbüchel 《Applied microbiology》2001,67(4):1964-1969
On complex medium Escherichia coli strains carrying hybrid plasmid pBEC/EE:11.0, pSKBEC/BE:9.0, pSKBEC/PP:3.3, or pSKBEC/PP:2.4 harboring genomic DNA of Ralstonia eutropha HF39 produced a blue pigment characterized as indigo by several chemical and spectroscopic methods. A 1,251-bp open reading frame (bec) was cloned and sequenced. The deduced amino acid sequence of bec showed only weak similarities to short-chain acyl-coenzyme A dehydrogenases, and the gene product catalyzed formation of indoxyl, a reactive preliminary stage for production of indigo. 相似文献
998.
Light and temperature dependent inhibition of photosynthesis in frost-hardened and un-hardened seedlings of pine 总被引:1,自引:0,他引:1
Needles of un-hardened and frost-hardended seedlings of Pinus sylvestris and Pinus contorta were exposed to photoinhibitory photon flux densities at temperatures between 0 and 35°C under laboratory conditions. Photoinhibition of photosynthesis was assayed by measuring oxygen evolution under saturating CO2 in a leaf disc oxygen electrode or by recording of photosystem II fluorescence induction kinetics at 77 K. It was demonstrated that frost hardening of pine did not affect the susceptibility of photosynthesis to short time (2 h) photoinhibition at 15°C. The two pine species irrespective of acclimative state were equally sensitive to photoinhibition as assayed by apparent photon yield analyses of photosynthetic oxygen evolution. Plots of the apparent photon yield of oxygen evolution vs. F
v
/F
m
revealed a non-linear relationship.In the temperature range of 15–20°C short term photoinhibition caused a loss of F
v
without effect on F
0
. However, photoinhibition at temperatures lower or higher caused F
0
to increase and decrease, respectively. In fact the decrease of F
v
v
/F
upon lowering the temperature was mainly caused by the temperature effect on F
0
. Besides photoinhibition causing the well established quenching of F
v
by increased radiationless decay somewhere in the reaction center-antenna complex, it is suggested that F
0
generally increases as a result of loss of functional reaction centers causing decreased trapping of excitation energy. However, the high temperature induced quenching of F
0
suggests that the quenching process (or processes) induced under photoinhibitory conditions is temperature dependent; i.e. it increases with the increase of temperature.In pine the photon yield of photosynthesis was much more sensitive to short term photoinhibition than was the rate of light saturated photosynthesis. This difference is explained by photosystem II and electron transport having surplus capacity relative to that of reductive carbon metabolism. 相似文献
999.
1000.
1. Egg size is often used as a proxy of egg quality although size and composition may vary, e.g. in insects egg size usually decreases as female ages. Whether this decrease in size reflects reduced concentrations of essential nutrients such as lipids and proteins of eggs laid by ageing females, or does reduced size per se explain often observed lower fitness of later laid eggs is poorly explored. 2. Egg properties were compared with fitness parameters of offspring laid on the first and fourth night during the oviposition period of a capital breeding moth, Cleorodes lichenaria (Hufnagel). The study aim was to explore whether decreased egg size is caused by decreased provisioning into later laid eggs measured as egg protein and lipid concentration, and whether it results in lower fitness of later laid offspring. 3. The fresh and dry weight of eggs decreased over the oviposition period, but the protein and lipid concentration remained constant. Survival of larvae was lower among the fourth night laid offspring on a low quality host Parmelia sulcata Taylor compared to a high quality host Ramalina fraxinea (L.) Ach. No differences were observed in egg fertility or hatchability, neonate survival without food and pupal mass between the offspring produced on different nights. 4. Decreased survival of offspring produced later was rather attributable to absolute provisioning (i.e. lower weight of eggs) than relative provisioning (i.e. decreased concentrations of nutrients in eggs). It is argued that lower survival of later laid smaller eggs on low quality diet is likely attributable to physical and chemical characteristics of host lichens and/or physical properties of tiny neonate larvae. 相似文献