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991.
Baumgarner BL Riley CP Sepulveda MS Brown PB Meyer JL Adamec J 《Fish physiology and biochemistry》2012,38(2):319-327
Short-term starvation has been linked to in vivo protein degradation in liver of rainbow trout (Oncorhynchus mykiss). However, it is unclear whether this proposed increase in protein degradation is followed by programmed cell death (apoptosis)
in liver of starved trout. A preliminary study in our laboratory revealed an isoform of glyceraldehyde-3-phosphate dehydrogenase
(GAPDH) protein that increased 4.5-fold in liver of starved trout. GAPDH is a glycolytic enzyme involved in other cellular
functions, including apoptosis. Increased intracellular nitric oxide (NO) promotes nuclear translocation of GAPDH that is
associated with increased apoptosis in mammals. If GAPDH protein is associated with apoptosis in rainbow trout, it could potentially
be used as a biomarker of cellular stress in liver of teleost fish species. The purpose of this study was to determine whether
increased GAPDH protein expression in liver of starved rainbow trout is associated with NO-induced apoptosis. Targeted proteomic
analysis using multiple reaction monitoring (MRM) was used to determine the level of GAPDH in nuclear and cytoplasmic fractions
and inducible nitric oxide synthase (iNOS) in cell lysates. Dot blot and DNA fragmentation analyses were conducted to evaluate
protein S-nitrosylation and apoptosis, respectively. Results showed that cytoplasmic GAPDH was 3.4-fold higher in liver of
starved versus fed rainbow trout but could not be detected in nuclear fractions. Starvation significantly reduced hepato-somatic
index but had no effect on iNOS protein expression, protein S-nitrosylation, or apoptosis. Our results indicate that starvation
promoted significant reduction in liver mass that was not associated with increased apoptosis or NO-induced stress and that
greater GAPDH concentration in liver of starved rainbow trout was located primarily in the cytoplasm. 相似文献
992.
The status of the Potato virus Y (PVY) in Swiss seed potato production was investigated in the years 2003 and 2008 by analysing 385 leaf samples of field-grown,
suspicious potato plants collected in four representative seed control fields. Serological investigations by ELISA showed
that in c. 84% of the PVY-positive samples in both years, viruses belonging to the PVYN group were found. All 124 serologically positive PVY samples collected in 2003 and a selection of 81 isolates of 2008 were
further typified by molecular tests and by biological assays on tobacco and potato plants. These tests largely confirmed the
predominance of the PVYN group and, within this group, the prevalence of recombinant PVYNTN, with 81.4% and 70.4% in 2003 and 2008, respectively. The percentage of PVYN-Wilga (PVYN-Wi) increased from c. 6% to 17% between the two years. PVYO was detected only in 10.5% and 4.9% of all molecularly analysed samples in 2003 and 2008, respectively. The persistent predominance
of recombinant PVYNTN in Swiss seed potatoes indicates that this strain group is now widespread, representing a considerable threat to Swiss seed
potato production. 相似文献
993.
Peter R. Gildemacher Elmar Schulte-Geldermann Dinah Borus Paul Demo Peter Kinyae Pauline Mundia Paul C. Struik 《Potato Research》2011,54(3):253-266
In Kenya, seed potato quality is often a major yield constraint in potato production as smallholder farmers use farm-saved
seed without proper management of seed-borne pests and diseases. Farm-saved seed is therefore often highly degenerated. We
carried out on-farm research to assess whether farmer-managed positive seed selection could improve yield. Positive selection
gave an average yield increase in farmer-managed trials of 34%, corresponding to a 284-€ increase in profit per hectare at
an additional production cost of only 6 €/ha. Positive selection can be an important alternative and complementary technology
to regular seed replacement, especially in the context of imperfect rural economies characterized by high risks of production
and insecure markets. It does not require cash investments and is thus accessible for all potato producers. It can also be
applied where access to high-quality seed is not guaranteed. The technology is also suitable for landraces and not recognized
cultivars that cannot be multiplied formally. Finally, the technology fits seamlessly within the seed systems of Sub-Saharan
Africa, which are dominated by self-supply and neighbour supply of seed potatoes. 相似文献
994.
Factors influencing the quality of half‐pearls (mabé) produced by the winged pearl oyster,Pteria penguin (Röding, 1758) 下载免费PDF全文
The winged pearl oyster, Pteria penguin, is cultured primarily to produce half‐pearls (mabé). The mabé quality is influenced by culture techniques, but there is limited information in this field. P. penguin with mean (±SE) dorso‐ventral height of 250 ± 6.5 mm were used to investigate the influence of culture period and nucleus position on mabé quality. Oysters were relaxed using 1‐propylene phenoxetol, and five nuclei were glued at different positions to the inner surfaces of the oyster shells; three on the more concave left valve and two on the right valve. Nucleated oysters were then cultured for 10 months under commercial pearl farming conditions at Savusavu in Fiji. Nacre deposited at the base and top of the nuclei was measured monthly, from the 6th to the 10th months of culture and the different qualities of mabé produced at different positions were scrutinized. Nacre thicknesses at the base and top of the resulting mabé were significantly different at different months (P < 0.05) and the rate of nacre deposition was highest during the warmer months. The different positions of nuclei on the valve greatly affected the quality of mabé formed. After a 10‐month culture period, around 1 mm of nacre covered the nuclei although the best quality mabé were obtained after 9 months. 相似文献
995.
996.
Fande Meng Decheng Jin Kai Guo Steven L. Larson John H. Ballard Liangmei Chen Zikri Arslan Guodong Yuan Jeremy R. White Lixiang Zhou Youhua Ma Charles A. Waggoner Fengxiang X. Han 《Water, air, and soil pollution》2018,229(11):369
Anthropogenic activities, such as ore mining and processing, nuclear power generation, and weapon tests, have generated uranium (U) contamination to soils and waters. The mobility and bioavailability of U are influenced by its sources, speciation, and plant species. Phytoremediation has emerged as an environmentally friendly, cost-effective green technology to remediate radioisotope- and metal-contaminated soils. The main objective of this study was to explore the feasibility using sunflower (Helianthus annuus) and Indian mustard (Brassica juncea) in cleaning up soils with UO2, UO3, and UO2(NO3)2. Uranium was found to be bioaccumulated in plant roots more than plant shoots. Uranium uptake by both plant species was significantly higher from the UO3- and uranyl-contaminated soils than from UO2-contaminated soils. UO3- and UO2(NO3)2-contaminated soils showed higher exchangeable, weak acid extractable, and labile U than the UO2-contaminated soils. After a growing season, three U forms decreased as redistribution/transformation of U resulted in U species with lower extractability. This study indicates the importance of U speciation in soil with regard to the potential use of sunflower and Indian mustard for phytoremediation of U-contaminated soils. 相似文献
997.
T.?ChitiEmail authorView authors OrcID profile A.?Rey K.?Jeffery M.?Lauteri V.?Mihindou Y.?Malhi F.?Marzaioli L.?J.?T.?White R.?Valentini 《Biology and Fertility of Soils》2018,54(8):897-907
In this study, we quantified the contribution of forest-derived carbon (FDC) to the soil organic C (SOC) pool along a natural succession from savanna (S) to mixed Marantaceae forest (MMF) in the Lopè National Park, Gabon. Four 1-ha plots, corresponding to different stages along the natural succession, were used to determine the SOC stock and soil C isotope composition (δ13C) to derive the FDC contribution in different soil layers down to 1 m depth. Besides, to investigate changes in SOC stability, we determined the 14C concentration of SOC to 30 cm depth and derived turnover time (TT). Results indicated that SOC increased only at the end of the succession in the MMF stage, which stored 46% more SOC (41 Mg C ha?1) in the 0–30 cm depth than the S stage (28.8 Mg C ha?1). The FDC contribution increased along forest succession affecting mainly the top layers of the initial successional stages to 15 cm depth and reaching 70 cm depth in the MMF stage. The TT suggests a small increase in stability in the 0–5 cm layer from S (146 years) to MMF (157 years) stages. Below 5 cm, the increase in stability was high, suggesting that FDC can remain in soils for a much longer time than savanna-derived C. In conclusion, the natural succession toward Marantaceae forests can positively impact climate change resulting in large SOC stocks, which can be removed from the atmosphere and stored for a much longer time in forest soils compared to savanna soils. 相似文献
998.
Zongzhuan?Shen Chao?Xue Paul?W.?J.?Taylor Yannan?Ou Beibei?Wang Yan?Zhao Yunze?Ruan Rong?LiEmail authorView authors OrcID profile Qirong?Shen 《Biology and Fertility of Soils》2018,54(7):793-806
Two seasonal pot experiments were conducted to investigate the effect of biofertilizer application after mixture of lime and ammonium bicarbonate (LA) fumigation, on banana Fusarium wilt disease suppression and soil microbial community composition. Biofertilizer application after LA fumigation decreased 80% of disease incidence compared to control of biofertilizer application to non-fumigated soil. Biofertilizer application after fumigation clearly manipulated soil microbial community composition as revealed by non-metric multidimensional scaling and Venn diagram. LA fumigation significantly reduced the abundance of F. oxysporum while biofertilizer application after fumigation could further decrease it. Furthermore, indigenous microbes, e.g., Bacillus, Pseudomonas, and Mortierella, were associated with disease suppression. Biofertilizer application after fumigation significantly (p?<?0.05) increased the soil pH and content of soil total C and available P and K, and this probably reshaped soil microbial community as revealed by redundancy analysis and variance partitioning analysis. The observed disease suppression due to biofertilizer application after soil fumigation can be attributed to the reduced abundance of F. oxysporum by general suppression resulting from manipulated soil properties and recovered soil microbiome. 相似文献
999.
目的 探讨二甲基亚砜(DMSO)代替N,N-二甲基甲酰胺(DMF)用于制霉菌素效价测定的可行性.方法 制霉菌素分别用DMSO和DMF溶解,采用美国药典中抗生素-微生物测定法检测制霉菌素效价.结果 DMF和DMSO均有较好的准确性、精密度、特异性、线性范围(10.0-40.0 U/mL)、检出限(2.0 U/mL)和稳定性,且DMSO方法的灵敏度、定量下限(LOQ,3.0 U/mL)优于DMF.结论 鉴于DMSO毒性明显低于DMF,且DMSO方法的分析性能特征与DMF法相当甚或更好,故DMSO可代替DMF作为溶剂用于制霉菌素活性测定. 相似文献
1000.