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2.
Hypersensitive response of wheat to the Hessian fly 总被引:3,自引:0,他引:3
Paul B. Grover Jr. 《Entomologia Experimentalis et Applicata》1995,74(3):283-294
Hessian flyMayetiola destructor (Say) larvae are able to obtain food from their host plant without inflicting mechanical damage to the plant surface, apparently
by secreting substances which elicit release of nutrients from plant cells surrounding the feeding site. Cells of fully susceptible
plants retain their normal appearances, while in resistant plants extensive areas of cellular collapse occur. These responses
indicate that hypersensitivity is the basis of wheat's resistance to the Hessian fly. The fly's feeding mechanism more closely
resembles that of a pathogen than of a phytophagous insect; correspondingly, both the genetic relationship and resistance
mechanism of the host plant to the parasite are of the sorts commonly associated with bacterial and fungal pathogens. 相似文献
3.
Shendge Anil Khushalrao Panja Sourav Mandal Nripendranath 《Molecular and cellular biochemistry》2021,476(5):2181-2192
Molecular and Cellular Biochemistry - Lichens are the symbiotic association between photobiont algae and mycobiont fungi having diverse phytochemicals. However, they are still an underexplored... 相似文献
4.
Yiwen Sun Zexuan Zhu Siping Chen Jega Balakrishnan Derek Abbott Anil T. Ahuja Emma Pickwell-MacPherson 《PloS one》2012,7(11)
The GP2 peptide is derived from the Human Epidermal growth factor Receptor 2 (HER2/nue), a marker protein for breast cancer present in saliva. In this paper we study the temperature dependent behavior of hydrated GP2 at terahertz frequencies and find that the peptide undergoes a dynamic transition between 200 and 220 K. By fitting suitable molecular models to the frequency response we determine the molecular processes involved above and below the transition temperature (T
D). In particular, we show that below T
D the dynamic transition is dominated by a simple harmonic vibration with a slow and temperature dependent relaxation time constant and that above T
D, the dynamic behavior is governed by two oscillators, one of which has a fast and temperature independent relaxation time constant and the other of which is a heavily damped oscillator with a slow and temperature dependent time constant. Furthermore a red shifting of the characteristic frequency of the damped oscillator was observed, confirming the presence of a non-harmonic vibration potential. Our measurements and modeling of GP2 highlight the unique capabilities of THz spectroscopy for protein characterization. 相似文献
5.
Diffusing capacity of the lung in Caucasians native to 3,100 m 总被引:2,自引:0,他引:2
A C DeGraff R F Grover R L Johnson J W Hammond J M Miller 《Journal of applied physiology》1970,29(1):71-76
6.
7.
Bhuvnesh Shrivastava Shilpi Thakur Yogender Pal Khasa Akshaya Gupte Anil Kumar Puniya Ramesh Chander Kuhad 《Biodegradation》2011,22(4):823-831
In order to improve the digestibility and nutrient availability in rumen, wheat straw was subjected to solid state fermentation
(SSF) with white-rot fungi (i.e. Pleurotus ostreatus and Trametes versicolor) and the fermented biomass (called myco-straw) was evaluated for biochemical, enzymatic and nutritional parameters. The fungal
treatment after 30 days led to significant decrease (P < 0.05) in cell wall constituents viz, acid detergent fiber (ADF), neutral detergent fiber (NDF), hemicellulose, lignin and
cellulose to the extent of 35.00, 38.88, 45.00, 37.48 and 37.86%, respectively in P. ostreatus fermented straw, while 30.04, 33.85, 39.90, 31.29 and 34.00%, respectively in T. versicolor fermented straw. However, maximum efficiency of fermentation in terms of low carbohydrate consumption per unit of lignin
degradation, favoring cattle feed production was observed for P. ostreatus on the 10th day (17.12%) as compared with T. versicolor on the 30th day (16.91%). The myco-straw was found to contain significantly high (P < 0.05) crude protein (CP; 4.77% T. versicolor, 5.08% P. ostreatus) as compared to control straw (3.37%). Metabolizable energy (ME, MJ/kg DM), percent organic matter digestibility (OMD) and
short chain fatty acids (SCFAs; mmol) production also increased considerably from control straw (4.40, 29.91 and 0.292) to
a maximum up to P. ostreatus fermented straw (4.92, 33.39 and 0.376 on 20th day) and T. versicolor fermented straw (4.66, 31.74 and 0.334 on 10th day), respectively. Moreover, the myco-straw had lower organic carbon and
was rich in nitrogen with lower C/N ratio as compared to control wheat straw. Results suggest that the fungal fermentation
of wheat straw effectively improved CP content, OM digestibility, SCFAs production, ME value and simultaneously lowered the
C/N ratio, thus showing potential for bioconversion of lignin rich wheat straw into high energy cattle feed. 相似文献
8.
Merih Anil 《Dialectical Anthropology》2005,29(3-4):453-470
Since the beginning of the 1990s, Germany has been taking controversial policy measures that had been quite unimaginable, even in the 1980s. On the one hand, regulations for asylum seekers and ethnic Germans have gradually become restrictive in nature. On the other hand, changes to the Citizenship and Nationality Law of 1913 (Reichs und Staatsangehörigkeitsgesetz) and the Alien Act of 1965 (Ausländergesetz) have dramatically altered the naturalization process. Before the passage of the new German citizenship law in 1999, the acquisition of citizenship in Germany was solely based on the principle of descent (jus sanguinis). This paper attempts to explain why German government altered its citizenship policy and introduced birthright citizenship. It reviews the post-war contextual factors that have shaped the debate on citizenship and asks whether it is external or internal factors, that is international-level norms and institutions or domestic politics, that led to the change. If domestic politics can fully explain the adoption of the new citizenship law, what domestic forces played an important role? Was state action taken in the name of protecting “the national interest” or was it party politics? What role did societal forces play in the making of new citizenship policy? Did the act seek to mitigate anti-foreigner sentiment growing in Germany since the 1990s? Using archival and documentary research and secondary data on socio-economic and demographic trends in Germany, this paper concludes that domestic politics explain the changes in the citizenship law. I argue that granting and withholding national citizenship, including birthright citizenship, is exclusively in the hands of a nation state. Considering a purely ethnocultural understanding of nation-hood now includes legal and territorial components, the new German citizenship law is a major reform at the both theoretical and conceptual level. However, the practical consequences of the new naturalization process remain to be seen. The main question for the future research agenda is whether the new naturalization and citizenship laws will bring full integration of foreigners living in German society. 相似文献
9.
Oxalate-stimulation of ATP-dependent Ca-uptake is diminished during smooth muscle subcellular fractionation 总被引:1,自引:0,他引:1
The ATP-dependent azide-insensitive Ca-uptake by the postnuclear supernatant from rat myometrium is stimulated more by 5 mM oxalate than by 25 mM phosphate. During subcellular fractionation, however, the percent recovery of the oxalate stimulated Ca-uptake diminishes more rapidly than that of the Ca-uptake without any added oxalate or phosphate. The percent recovery of the phosphate stimulated Ca-uptake also diminishes but not to as low levels as that of the oxalate stimulated Ca-uptake. The net result is higher stimulation of this uptake by 25 mM phosphate than by 5 mM oxalate in the various sucrose density gradient fractions. This discrepancy in percent recoveries presents a major concern about the use of oxalate or phosphate stimulated Ca-uptake as a marker for smooth muscle membranes. 相似文献
10.
Control of breathing in Sherpas at low and high altitude 总被引:2,自引:0,他引:2
Hackett P. H.; Reeves J. T.; Reeves C. D.; Grover R. F.; Rennie D. 《Journal of applied physiology》1980,49(3):374-379