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61.
The objective of this research was to study the effect of irrigation levels (five levels from 102 to 457 mm of water) on the physical and chemical properties and ethanol fermentation performance of maize. Twenty maize samples with two crop rotation systems, grain sorghum–maize and maize–maize, were harvested in 2011 and evaluated at the Kansas State University Southwest Research‐Extension Center near Garden City, Kansas, under a semiarid climate. Results showed that maize kernel weight, density, and breakage susceptibility decreased as irrigation level decreased. Starch contents of maize samples grown under a low irrigation level were approximately 3.0% lower than those under a high irrigation level. Protein contents ranged from 9.24 to 11.30% and increased as irrigation level decreased. Maize flour thermal and rheological properties were analyzed by differential scanning calorimetry and the Micro Visco‐Amylo‐Graph‐U device. Starch gelatinization temperature increased significantly as irrigation level decreased, whereas starch pasting viscosity decreased as irrigation level decreased. Free amino nitrogen (FAN) was significantly affected by irrigation level: it increased as irrigation decreased. Ethanol fermentation efficiency ranged from 90.96 to 92.48% and was positively correlated with FAN during the first 32 h of fermentation (r2 = 0.645). Deficit irrigation had a negative impact on ethanol yield. The maize with lower irrigation yielded about 4.0% less ethanol (44.14 mL/100 g of maize) than maize with high irrigation (45.92 mL/100 g of maize). Residual starch contents in the distillers dried grains with solubles were in a range of 0.80–1.02%. In conclusion, deficit irrigation had a significant effect on physical properties, chemical composition, ethanol yield, and fermentation efficiency of maize.  相似文献   
62.
In 2010, the highest annual number of human Puumala virus (PUUV) infections was reported in Germany since hantavirus surveillance started in 2001. The increase in annual case numbers was especially marked in western Thuringia. We combined results of case‐based hantavirus surveillance in humans and serological and molecular investigations in the rodent reservoir to describe the epidemiological situation and to identify the putative outbreak strain. A 5‐fold increase in notified hantavirus cases compared to the previous annual maximum was observed in western Thuringia in 2010. Disease incidence varied tremendously within a small geographical area with case patients' places of residence clustering around beech‐dominated broad leaf forest patches. Investigations in the rodent reservoir revealed a novel Puumala virus (PUUV) subtype, which is clearly distinct from strains collected in other PUUV endemic regions of Germany. It can be assumed that in regions in western Thuringia where hantavirus cases occurred in 2010 or previous outbreak years, PUUV has been present in the environment for a long time. Further studies are needed to elucidate the population dynamics and hantavirus prevalence of the rodent reservoir and driving ecological factors.  相似文献   
63.
Caffeine was shown to induce mitotic events in mammalian cells before DNA replication (S phase) was completed. Synchronized BHK cells that were arrested in early S phase underwent premature chromosome condensation, nuclear envelope breakdown, morphological "rounding up," and mitosis-specific phosphoprotein synthesis when they were exposed to caffeine. These mitotic responses occurred only after the cells had entered S phase and only while DNA synthesis was inhibited by more than 70 percent. Inhibitors of protein synthesis blocked these caffeine-induced events, while inhibitors of RNA synthesis had little effect. These results suggest that caffeine induces the translation or stabilizes the protein product (or products) of mitosis-related RNA that accumulates in S-phase cells when DNA replication is suppressed. The ability to chemically manipulate the onset of mitosis should be useful for studying the regulation of this event in mammalian cells.  相似文献   
64.
Non-mycorrhizal Norway spruce seedlings (Picea abies Karst.) and Norway spruce seedlings colonized with Paxillus involutus Fr. were grown in an axenic silica sand culture system. After successful mycorrhizal colonization, the seedlings were exposed to 200 or 800 micro M AlCl(3) for 10 weeks. In both non-mycorrhizal and mycorrhizal seedlings, exposure to Al significantly reduced root growth and the uptake of Mg and Ca. After 5 weeks of exposure to 800 micro M Al, the mycorrhizal seedlings had significantly higher chlorophyll concentrations than the non-mycorrhizal seedlings, although no difference in Mg nutrition was apparent. After 10 weeks of exposure to Al, both non-mycorrhizal and mycorrhizal seedlings exhibited needle chlorosis and reduced photosynthetic activity. However, the aluminum-induced reduction in shoot growth was largely ameliorated by colonization with P. involutus. We conclude that mycorrhizal colonization modifies the phytotoxic effects of Al in Norway spruce seedlings. However, differences in physiological responses to Al between mycorrhizal and non-mycorrhizal seedlings may be largely reduced in the long term as a result of impaired mineral nutrient uptake.  相似文献   
65.
Foliar applications of calcium salts are usually combined with fungicides. In the years 2002 and 2003, it was tested if this practice assures high rates of penetration of calcium. Amounts that penetrated in 24 h were measured at 20 °C using 45CaCl2. To ensure maximum penetration rates, humidity was maintained at 100 %. Sample size was 40 to 50 fruits, and data were presented as box plots because distribution of data was not normal. Median rates of penetration of CaCl2, measured with mixtures of fungicides and CaCl2 at 5 or 10 g l–1, respectively, were very slow, and amounted to only a few percent of the dose applied. Rates were a little higher with very young fruits (55 days after full bloom, DAFB). Adding alkyl polyglycoside surfactants at 0.2 g l–1 significantly decreased surface tensions, and increased rates of penetration by up to 15‐fold. Still, total penetration of CaCl2 rarely exceeded 20 % of the dose applied (median penetration), even in the presence of an additional surfactant. In all treatments, outliers with 60 to 100 % penetration in 24 h occurred, and this was attributed to penetration into lenticels. This is expected to result in unequal concentrations of calcium in fruits, especially in the sub‐epidermal layers. Addition of a suitable surfactant to mixtures of fungicides with CaCl2 is strongly recommended as it enhances wetting and greatly increases penetration rates of CaCl2.  相似文献   
66.
67.
One hundred-sixty Holstein growing-finishing steers (initial BW of 185 kg) were blocked by BW to determine the effectiveness of long-term bovine somatotropin (bST) administration on lean, skeletal, and carcass measurements. Steers were randomly allocated to 4 treatments (10 steers/treatment) within a block (n = 4 blocks). Treatments were control, no bST (C-C); bST from d 0 to 182 (bST-C); bST from d 183 to slaughter (C-bST); and bST from d 0 to slaughter (bST-bST). Steers received a s.c. injection of placebo or bST at 14-d intervals. Doses were 320 mg of bST/injection from d 0 to 112 and 640 mg of bST/injection from d 113 to slaughter. The last treatment was administered 31 d before slaughter. Steers received a 14% CP (DM basis) diet from d 0 to 182 and 11.5% CP from d 183 to slaughter that consisted of dry, whole-shelled corn and a pelleted protein-mineral supplement. Steers were slaughtered when BW per block averaged 615 kg (d 325, 353, 367, and 381 for the 4 blocks, respectively). Thirty steers were removed from the study because of poor performance with respect to their pen mates, illness, lameness, death, incomplete castration, and incorrect treatment. Serum IGF-I concentrations increased 151% (P < 0.01) from d 7 through 35 in bST-treated steers compared with control steers. During the first 182 d, bST-C and bST-bST steers were heavier (P < 0.01) and had greater (P < 0.01) ADG, G:F, hip height, and hip height gain compared with C-C and C-bST steers. From d 183 to slaughter, C-bST steers had reduced (P < 0.05) daily DMI and greater G:F than bST-C steers. At final slaughter, C-bST and bST-bST steers had greater (P < 0.05) hip height than C-C steers. Noncarcass weight was increased and dressing percent reduced (P < 0.05) in C-bST and bST-bST steers compared with C-C steers. Quality grade was least (P < 0.05) in bST-bST carcasses compared with C-C, whereas bST-C and C-bST carcasses were intermediate. At final slaughter, steers receiving bST had greater (P < 0.05) carcass protein and water composition and lower (P < 0.05) carcass lipid and lipid accretion than C-C steers. Bovine somatotropin was effective in reducing carcass fat and increasing edible lean. Administering bST to young, lightweight steers increased skeletal growth and noncarcass weight without an increase in total carcass weight, but decreased carcass quality.  相似文献   
68.
Fibroblast growth factor 21 (FGF21) has been identified as a novel hormonal factor involved in the regulation of metabolic adaptations during energy deprivation. The present study aimed to investigate the expression of the FGF21 gene in the liver of dairy cows during the transition from pregnancy to lactation. Therefore, the relative mRNA abundance of FGF21 in liver biopsy samples of 20 dairy cows in late pregnancy (3 weeks pre‐partum) and early lactation (1, 5, 14 weeks post‐partum) was determined. It was observed that hepatic mRNA abundance of FGF21 at 1 week post‐partum was dramatically increased (110‐fold) compared to 3 weeks pre‐partum (p < 0.001). With progress of lactation, mRNA concentration of FGF21 was declining; nevertheless, mRNA abundance at 5 and 14 weeks post‐partum remained 25‐ and 10‐fold increased compared to 3 weeks pre‐partum (p < 0.001). Using a gene array technique, it was found that many genes involved in fatty acid oxidation, gluconeogenesis and ketogenesis were up‐regulated during early lactation compared to late pregnancy. Moreover, there were positive linear correlations between hepatic mRNA concentration of FGF21 and mRNA concentrations of genes involved in ketogenesis as well as carnitine synthesis and carnitine uptake at various time‐points during lactation, indicating that FGF21 could play a role in ketogenesis and carnitine metabolism in the liver of dairy cows (p < 0.05). In overall, the present study shows that expression of the FGF21 gene is strongly up‐regulated during the transition period. It is assumed that the up‐regulation of FGF21 might play an important role in the adaptation of liver metabolism during early lactation in dairy cows such as in other species.  相似文献   
69.
The reaction of the Nalpha-hippuryllysine (BzGK) with fructose was investigated in two model systems to obtain an insight in fructose-induced modification of lysine in bakery products. After BzGK and fructose had been heated in a buffered low-moisture model system (80 degrees C, 60 min, aW = 0.86, pH 7.4), formation of epimeric Heyns compounds Nalpha-hippuryl-Nepsilon-glucosyl-lysine (BzGGlcK) and Nalpha-hippuryl-Nepsilon-mannosyl-lysine (BzGManK) was clearly demonstrated using RP-HPLC with UV as well as MS detection. The Amadori compound Nalpha-hippuryl-Nepsilon-fructosyl-lysine (BzGFruK) was formed in glucose-containing samples. When BzGK was added to the dough of fructose-containing biscuits, the Heyns compounds were detectable after baking at 175 degrees C for 7 min. The yields of the Heyns compounds in the fructose-containing biscuits and the yield of the Amadori compound in the glucose-containing biscuits were determined to 33 and 63%, pointing to the fact that formation of substantial amounts of Heyns products is very likely in fructose-containing bakery products.  相似文献   
70.
This study examined known or possible virulence-associated genes in type A Clostridium perfringens from cases of both bovine clostridial abomasitis (BCA) and jejunal hemorrhage syndrome (JHS) and compared these to isolates from calves that were healthy or had undifferentiated diarrheal illness. A real-time polymerase chain reaction (PCR) assay was used to genotype the 218 C. perfringens isolates. Isolates were sourced from healthy and diarrheic young and mature cattle (n = 191), from calves with confirmed or suspected BCA (n = 22), and from mature cattle with JHS (n = 5). Of 216 isolates (96%), 208 were positive for the cpa gene and 13% (29/218) were positive for atypical cpb2. Three of 8 (37.5%) confirmed BCA isolates, 2 of 13 (15.4%) suspected BCA isolates, and no JHS isolates tested positive for atypical cpb2. As all isolates were negative for cpb, cpb2, cpe, etx, netB, and tpeL, the results of the present study do not support a role for these genes in BCA or JHS. A subset of unique genes identified in 1 bovine clostridial abomasitis isolate (F262), for which a genome sequence is available, was searched for in 8 BCA isolates by PCR. None of the 10 genes was consistently present in all or even in a majority of BCA isolates. Many of these genes were also variably and inconsistently present in type A isolates from calves that did not have BCA. Although a virulence signature to aid in the diagnosis of BCA caused by C. perfringens type A was not identified, further work may discover a gene or group of genes that would constitute such a signature.  相似文献   
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