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91.
Nakagawa T Kitagawa H Yasuda Y Tarasov PE Nishida K Gotanda K Sawai Y;Yangtze River Civilization Program Members 《Science (New York, N.Y.)》2003,299(5607):688-691
Pollen records from the annually laminated sediment sequence in Lake Suigetsu, Japan, suggest a sequence of climate changes during the Last Termination that resembles that of the North Atlantic region but with noticeable differences in timing. An interstadial interval commenced a few centuries earlier [approximately 15,000 years before the present (yr B.P.)] than the North Atlantic GI-1 (B?lling) event. Conversely, the onset of a Younger Dryas (YD)-like cold reversal (12,300 to 11,250 yr B.P.) postdated the North Atlantic GS-1 (YD) event by a few centuries. Climate in the Far East during the Last Termination reflected solar insolation changes as much as Atlantic influences. 相似文献
92.
93.
Neurotransmitter release is triggered by calcium ions and depends critically on the correct function of three types of SNARE [soluble N-ethylmaleimide-sensitive factor attachment protein (SNAP) receptor] proteins. With use of the large calyx of Held presynaptic terminal from rats, we found that cleavage of different SNARE proteins by clostridial neurotoxins caused distinct kinetic changes in neurotransmitter release. When elevating calcium ion concentration directly at the presynaptic terminal with the use of caged calcium, cleavage of SNAP-25 by botulinum toxin A (BoNT/A) produced a strong reduction in the calcium sensitivity for release, whereas cleavage of syntaxin using BoNT/C1 and synaptobrevin using tetanus toxin (TeNT) produced an all-or-nothing block without changing the kinetics of remaining vesicles. When stimulating release by calcium influx through channels, a difference between BoNT/C1 and TeNT emerged, which suggests that cleavage of synaptobrevin modifies the coupling between channels and release-competent vesicles. 相似文献
94.
95.
Zhou M Morgner N Barrera NP Politis A Isaacson SC Matak-Vinković D Murata T Bernal RA Stock D Robinson CV 《Science (New York, N.Y.)》2011,334(6054):380-385
The ability of electrospray to propel large viruses into a mass spectrometer is established and is rationalized by analogy to the atmospheric transmission of the common cold. Much less clear is the fate of membrane-embedded molecular machines in the gas phase. Here we show that rotary adenosine triphosphatases (ATPases)/synthases from Thermus thermophilus and Enterococcus hirae can be maintained intact with membrane and soluble subunit interactions preserved in vacuum. Mass spectra reveal subunit stoichiometries and the identity of tightly bound lipids within the membrane rotors. Moreover, subcomplexes formed in solution and gas phases reveal the regulatory effects of nucleotide binding on both ATP hydrolysis and proton translocation. Consequently, we can link specific lipid and nucleotide binding with distinct regulatory roles. 相似文献
96.
The membrane rotor ring from the vacuolar-type (V-type) sodium ion-pumping adenosine triphosphatase (Na+-ATPase) from Enterococcus hirae consists of 10 NtpK subunits, which are homologs of the 16-kilodalton and 8-kilodalton proteolipids found in other V-ATPases and in F1Fo- or F-ATPases, respectively. Each NtpK subunit has four transmembrane alpha helices, with a sodium ion bound between helices 2 and 4 at a site buried deeply in the membrane that includes the essential residue glutamate-139. This site is probably connected to the membrane surface by two half-channels in subunit NtpI, against which the ring rotates. Symmetry mismatch between the rotor and catalytic domains appears to be an intrinsic feature of both V- and F-ATPases. 相似文献
97.
Masafumi KATAYAMA Tomokazu FUKUDA Toshihiro OKAMURA Eisaku SUZUKI Katsuo TAMURA Yuuko SHIMIZU Yoshihito SUDA Keiichi SUZUKI 《Animal Science Journal》2011,82(2):274-281
In pig production, dietary additive antibiotics are usually used for growth stimulation and disease prevention, although there is public concern about the increased incidence of resistant antibiotics and food safety. It is possible that such antibiotics might be replaced by naturally derived products such as seaweed and licorice. In this study, we evaluated the effect of dietary addition of seaweed and licorice on enhancing the immune function in swine. The animals of each group (eight animals per group) were sensitized at day 42 and 49, and the immunoglobulin production and the expression of cytokines were detected by the ELISA and real‐time PCR. As the results, saliva IgA production of the seaweed‐treated group increased around five times compared to that of control (day 56). Delayed hypersensitivity reaction and IgG production of the seaweed‐treated group increased around 1.8–2.0 times. In addition, enhanced saliva IgA production was detected at day 50 (around two times) and day 51 (around five times) by the licorice treatment, and lower expression level of tumor necrosis factor‐α messenger RNA at day 51 (around 1/25) was observed in the licorice treatment. We conclude that the replacement of antibiotics by naturally derived dietary additives might be feasible for immune system enhancement. 相似文献
98.
Masamitsu TOMIYAMA Shouhei KUBO Tsutomu TAKAGI Keiichi SUZUKI 《Animal Science Journal》2011,82(5):621-626
Genetic improvement of the reproductive performance of pigs is important for pig breeding despite their low heritabilities. The objectives of this study were to investigate the effectiveness of selection concerning reproductive traits and to determine the optimal number of parity records required for accurate estimation of breeding values (BVs) in the open population of a commercial pig breeding company. The study used records of 2220 purebred Large White pigs (9845 litters) farrowed between 1998 and 2009 in the two herds of the Pacific Ocean Breeding Co. Ltd. The traits studied included farrowing interval (FI), total number of piglets at birth (TNB), average weaning weight per litter (AWW), and raising rate (RR). A statistical model was applied to the 4‐trait repeatability animal model. The heritabilities of FI, TNB, AWW and RR were low. The genetic trends in TNB (h2 = 0.09) showed approximately 1.0 increase in 6 years from 2003 to 2008. The predicted error variances indicated that up to fourth parity records are necessary for accurate genetic evaluation. The present study results indicated that even reproductive traits with low heritability can be improved. 相似文献
99.
We investigated the changes in the plasma concentrations of oxidative stress markers in periparturient dairy cows in hot conditions. This study was performed on 10 cows from day ?5 to day 10 after parturition. The experimental duration was divided into three periods: period 1 (5 days before parturition); period 2 (5 days after parturition); and period 3 (from day 6 to day 10 after parturition). The average rectal temperature in the cows during the experimental period was more than 39°C. Plasma aspartate aminotransferase activities in periods 2 and 3 were higher than that in period 1 (P < 0.05). Blood urea nitrogen concentration in period 3 was lower than those in periods 1 and 2 (P < 0.05). The total ascorbic acid concentration in the plasma in period 2 was greater than those in periods 1 and 3 (P < 0.05). Thiobarbituric acid reactive substances (TBARS) concentrations in periods 2 and 3 were greater than that in period 1 (P < 0.05). TBARS concentration was positively correlated with aspartate aminotransferase activity (P < 0.05). These results suggested that oxidative stress increased in cows after parturition under hot climatic conditions. 相似文献
100.
Shinpei Banno Hidenari Saito Hiroshi Sakai Toshihiko Urushibara Kentaro Ikeda Takeshi Kabe Isao Kemmochi Makoto Fujimura 《Journal of General Plant Pathology》2011,77(5):282-291
Verticillium longisporum and V. dahliae, causal agents of Verticillium wilt, are spreading through the cabbage fields of Gunma Prefecture. Using the V. longisporum-specific intron within the 18S rDNA and differences between ITS 5.8S rDNA sequences in Japanese isolates of V. longisporum and V. dahliae, we developed three quantitative nested real-time (QNRT) PCR assays. The QNRT-PCR quantification of V. longisporum or V. dahliae in cabbage field soil was consistent with the severity of Verticillium wilt disease in those fields. In field trials of resistant
cultivar YR Ranpo grown for three seasons in soil infested with the pathogen, disease severity and pathogen density in the
soil were significantly reduced in a field moderately contaminated by V. dahliae, but only slightly reduced in a highly contaminated field. These results suggest that continuous cultivation of a resistant
cultivar is an effective way to reduce the pathogen population. QNRT-PCR assays provide a powerful analytical tool to evaluate
the soil population dynamics of V. longisporum and V. dahliae for disease management. 相似文献