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排序方式: 共有1615条查询结果,搜索用时 859 毫秒
1.
Roland W. S. Weber 《Erwerbs-Obstbau》2009,51(3):115-120
Whereas the rise in temperature during the past 30–40 years has already had clear impacts on the phenology of fruit trees and pathogenic insects, there is a lack of such correlations for fungal pathogens. An examination of fruit rots indicates that pathogenic fungi react differentially to climate change due to their complex infection biology. The appearance of the black rot fungus Diplodia seriata in Northwestern Europe is best explained by rising temperatures during the vegetation period. An increase in fruit rot caused by Nectria galligena is anticipated when milder and more humid winter months favour canker formation on twigs and branches, thereby increasing inoculum for fruit infections. An increasing importance of Neofabraea alba and Glomerella cingulata and/or G.??acutata as storage rots of apples in Northern Germany cannot be safely correlated with the climate change at present. Research on fungi is currently being expanded at the OVB Jork in order to ensure a faster identification of new pathogens and a more thorough investigation of relevant features of their infection biology. 相似文献
2.
Revierförfter von Mühlen zu Solitude 《European Journal of Forest Research》1868,12(1):340-342
Ohne Zusammenfassung
Bergleiche Auguftheft diefer Bl?tter, in melchem gleichfalls auf die Wichtigfeit diefes Qegenftandes hingemiefen murde. Die
Red. 相似文献
3.
A. Lindner Dr med vet l; P. von Wittke Dr. med vet; M. Schmald J. Kusserow H. Sommer Dr habil Dr med vet 《Journal of Equine Veterinary Science》1992,12(1)
Lactate kinetics in whole blood of horses was investigated after exercise of differing velocities and duration. The following categories of exercise were used: A: <11 m/second and >180 seconds (n=35), B: >11 m/second and <180 seconds (n=17) and C: <11 m/second and <180 s (n=10). The mean peak lactate concentration determined in horses in category A was 4.49 ± 2.21 mmol/1, in B, 16.32 ± 4.81 mmoVl and in C, 4.58 ± 1.59 mmol/l. While the maximum lactate concentrations in categories A and C were always found immediately after the exercise, the peaks in category B were measured between the first and tenth minute after exercise. Mean lactate concentrations measured at 2-minute intervals after bouts of category-B exercise tended to stabilize 3 to 10 minutes after exercise; however, mean lactate concentrations measured during the intervals before and after the peak value differed significantly. The lactate concentration returned to pre-exercise levels within 20 minutes after exercise bouts of category C, but remained above pre-exercise levels up to 60 minutes after bouts of category-A and -B exercise. It was concluded that, for an evaluation of lactate data after intensive anaerobic exercise, sequential blood sampling at 2-minute intervals for a period of up to 12 minutes after exercise is necessary. Less frequent sampling may be a reason for the often described irreproducibility of lactate concentrations in horses. After aerobic or mild anaerobic exercise, one sample is sufficient, but it has to be taken as soon as possible after exercise. 相似文献
4.
H Adam G von Lengerken D Olthoff M Schwalbe M Wicke 《Archiv fuer experimentelle veterinaermedizin》1989,43(2):293-299
Membraneous phospholipids of subcellular structures were determined from the musculature of German Landrace pigs of the GDR, following exposure to halothane. Mating variants A (H+ male X H+ female), B (H+ male X H- female), and C (H- male X H+ female) were used for positive responders (MHS), while variants B, C, and D (H- male X H- female) were used for negative responders (MHN). Four phospholipid fractions were recorded from the muscle samples for mitochondria and microsomes (according to SR section). Differences between the MHS and MHN groups for the above fractions and without consideration of mating variants and genotype were not observed, although unambiguous responses were exhibited by all animals, either positive or negative to halothan. Significant differences with regard to the above phospholipid fractions were recordable only for variant A (MHS group) as compared to D (MHN), in other words, for the homozygous genotypes, once the above results had been rearranged within MHS and MHN along with different mating variants and genotypes. However, no unambiguous results were obtainable for the heterozygous genotypes of mating variants B and C. Possible underlying reasons are discussed in some detail. The results obtained from mating variants A and D are likely to confirm earlier findings and seem to suggest that the sarcoplasmic reticulum is the primary site of origin of susceptibility to halothane or malignant hyperthermia. 相似文献
5.
Dr. Erika von Winning 《Journal of pest science》1948,21(9):141-142
Ohne Zusammenfassung 相似文献
6.
Colitis cystica profunda in dogs has been diagnosed in one case only. The two own cases were characterized by repeated, partly bloody diarrhea, vomitus, and painful defecation. The disease was diagnosed by clinical examination and colonoscopy with the ensuing histological examination of biopsy specimens. The disease could be managed by administration of a diet, sulfasalazine and corticosteroids. 相似文献
7.
8.
Safety of standardized Macleaya cordata extract in an eighty‐four‐day dietary study in dairy cows 下载免费PDF全文
W. Wang L. C. Dolan S. von Alvensleben M. Morlacchini G. Fusconi 《Journal of animal physiology and animal nutrition》2018,102(1):e61-e68
The objective of this study was to evaluate the safety of a standardized Macleaya cordata Extract Product (MCEP) containing the quaternary benzophenanthridine alkaloids, sanguinarine and chelerythrine, when fed to dairy cows. Thirty‐six dairy cows were randomized into three groups with twelve cows/treatment in two replica pens for each treatment group: control (C) without MCEP added to feed, treatment 1 (SANG‐1000) with MCEP added to feed at 1,000 mg/animal/day (1.5 mg/kg bw/day) and treatment 2 (SANG‐10000) with MCEP added to feed at 10,000 mg/animal/day (15.5 mg MCEP/kg bw/day). After two weeks of acclimation, animals were observed for an 84‐day experimental period, with body weight, feed intake and milk production measured daily. Milk composition was analysed every two weeks. Haematological analyses were performed on Day 0 and Day 84, and clinical chemistry analyses were performed on Day 84 of the study. There was no statistically significant difference (p > .10) among the three groups on body condition score, milk production or milk composition over the study period. There were no significant differences in body weight gain or feed consumption among the three groups. Animals in the SANG‐10000 group had significantly higher mean corpuscular volume (MCV) than the C group (p < .1) and lower mean corpuscular haemoglobin concentration (MCHC) than the SANG‐1000 group (p < .1). Concentrations of sanguinarine and chelerythrine in milk samples collected on Day 84 were below the detection limit (LOD) as measured by high‐performance liquid chromatography‐mass spectrometry (HPLC‐MS/MS). In conclusion, this study presents compelling data supporting the hypothesis that the test product MCEP, when included in the TMR at up to 10,000 mg/animal/day (15.5 mg MCEP/kg bw/day), is well tolerated by dairy cows. 相似文献
9.
Yi Zhao Shuxia Wu Roland Bol Mansoor Ahmed Bughio Wenliang Wu Yecui Hu Fanqiao Meng 《植物养料与土壤学杂志》2020,183(2):155-168
Intensive vegetable production in greenhouses has rapidly expanded in China since the 1990s and increased to 1.3 million ha of farmland by 2016, which is the highest in the world. We conducted an 11‐year greenhouse vegetable production experiment from 2002 to 2013 to observe soil organic carbon (SOC) dynamics under three management systems, i.e., conventional (CON), integrated (ING), and intensive organic (ORG) farming. Soil samples (0–20 and 20–40 cm depth) were collected in 2002 and 2013 and separated into four particle‐size fractions, i.e., coarse sand (> 250 µm), fine sand (250–53 µm), silt (53–2 µm), and clay (< 2 µm). The SOC contents and δ13C values of the whole soil and the four particle‐size fractions were analyzed. After 11 years of vegetable farming, ORG and ING significantly increased SOC stocks (0–20 cm) by 4008 ± 36.6 and 2880 ± 365 kg C ha?1 y?1, respectively, 8.1‐ and 5.8‐times that of CON (494 ± 42.6 kg C ha?1 y?1). The SOC stock increase in ORG at 20–40 cm depth was 245 ± 66.4 kg C ha?1 y?1, significantly higher than in ING (66 ± 13.4 kg C ha?1 y?1) and CON (109 ± 44.8 kg C ha?1 y?1). Analyses of 13C revealed a significant increase in newly produced SOC in both soil layers in ORG. However, the carbon conversion efficiency (CE: increased organic carbon in soil divided by organic carbon input) was lower in ORG (14.4%–21.7%) than in ING (18.2%–27.4%). Among the four particle‐sizes in the 0–20 cm layer, the silt fraction exhibited the largest proportion of increase in SOC content (57.8% and 55.4% of the SOC increase in ORG and ING, respectively). A similar trend was detected in the 20–40 cm soil layer. Over all, intensive organic (ORG) vegetable production increases soil organic carbon but with a lower carbon conversion efficiency than integrated (ING) management. 相似文献
10.