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81.
Systolic and diastolic myocardial dysfunction in cats with hypertrophic cardiomyopathy or systemic hypertension 总被引:2,自引:0,他引:2
Carlos Sampedrano C Chetboul V Gouni V Nicolle AP Pouchelon JL Tissier R 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(5):1106-1115
BACKGROUND: Hypertrophic cardiomyopathy (HCM) and chronic systemic hypertension (SHT) can both lead to left-ventricular hypertrophy (LVH) in cats. Assessment of LVH-associated myocardial dysfunction could provide new insights in the understanding of the pathophysiology of these diseases. HYPOTHESIS: Quantification of left-ventricular free-wall (LVFW) motion using tissue Doppler imaging (TDI) could permit differentiation of feline HCM from SHT-related LVH (LVH-SHT). ANIMALS: A total of 108 cats of different breeds were enrolled in this study: 35 cats with HCM, 17 with concentric LVH and SHT, and 56 healthy cats as a control group. METHODS: All cats were examined by conventional echocardiography and 2-dimensional color TDI. RESULTS: Radial and longitudinal diastolic LVFW velocities were similarly altered in cats with HCM and LVH-SHT, compared to controls. Systolic velocities were also lower in the groups with hypertrophy than in the controls, for longitudinal but not radial motion. To determine whether these diastolic and systolic alterations could also be observed in cats without LVFW hypertrophy, we performed a subgroup analysis in cats with a normal M-mode examination, that is, with only a localized subaortic interventricular septum hypertrophy. A significant radial and longitudinal diastolic dysfunction was still observed in both the HCM and LVH-SHT groups compared to controls, and systolic dysfunction was detected in the longitudinal motion. CONCLUSIONS: LVFW motion is similarly altered in cats with HCM and LVH-SHT. This dysfunction occurs independently of the presence of myocardial hypertrophy, demonstrating that TDI is capable of detecting systolic and diastolic segmental functional changes in nonhypertrophied wall segments in cats with HCM and SHT. 相似文献
82.
Chetboul V Blot S Sampedrano CC Thibaud JL Granger N Tissier R Bruneval P Gaschen F Gouni V Nicolle AP Pouchelon JL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(3):640-647
Diagnosis of feline hypertrophic cardiomyopathy currently is based on the presence of myocardial hypertrophy detected using conventional echocardiography. The accuracy of tissue Doppler imaging (TDI) for earlier detection of the disease has never been described. The objective of this sudy was to quantify left ventricular free wall (LVFW) velocities in cats with hypertrophic muscular dystrophy (HFMD) during preclinical cardiomyopathy using TDI. The study animals included 22 healthy controls and 7 cats belonging to a family of cats with HFMD (2 affected adult males, 2 heterozygous adult females, one 2.5-month-old affected male kitten, and 2 phenotypically normal female kittens from the same litter). All cats were examined via conventional echocardiography and 2-dimensional color TDI. No LVFW hypertrophy was detected in the 2 carriers or in the affected kitten when using conventional echocardiography and histologic examination, respectively. The LVFW also was normal for 1 affected male and at the upper limit of normal for the 2nd male. Conversely, LVFW dysfunction was detected in all affected and carrier cats with HFMD when using TDI. TDI consistently detects LVFW dysfunction in cats with HFMD despite the absence of myocardial hypertrophy. Therefore, TDI appears more sensitive than conventional echocardiography in detecting regional myocardial abnormalities. 相似文献
83.
Mogensen BB Krongaard T Mathiassen SK Kudsk P 《Journal of agricultural and food chemistry》2006,54(4):1023-1030
Three varieties of winter wheat (Triticum aestivum) were grown in both conventional and organic farming systems. The contents of the benzoxazinone derivatives 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), 2-beta-d-glucopyranosyloxy-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA-Glc), 6-methoxybenzoxazolin-2-one (MBOA), 2-hydroxy-7-methoxy-1,4-benzoxazin-3-one (HMBOA), benzoxazolin-2-one (BOA), and 2-hydroxy-1,4-benzoxazin-3-one (HBOA) were analyzed at five growth stages (BBCH 9-10, 12, 21, 31, and 53). Major differences were found between the varieties, with Stakado exhibiting the highest contents. In contrast, only minor and erratic differences were found between the two farming systems, suggesting that the inherent differences in the content of benzoxazinone derivatives of the varieties were not significantly affected by the use of pesticides and synthetic fertilizers. The concentration of benzoxazinone derivatives in the foliage was considerably higher at the early growth stages than later in the growing season, with DIMBOA being the most abundant of the benzoxazinone derivatives. An increase in the concentration was observed in early spring compared to late autumn, suggesting that plants synthesized benzoxazinone derivatives at the commencement of growth in early spring. The concentrations in the roots were considerably lower than in the foliage at the early growth stages but remained relatively constant over time, resulting in a higher concentration than in the foliage at the late growth stages. The results are discussed in relation to previous findings that predominantly originate from experiments done under controlled conditions in either growth cabinets or greenhouses. 相似文献
84.
The hydroxamic acid 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) and the benzoxazolinones benzoxazolin-2-one (BOA) and 6-methoxybenzoxazolin-2-one (MBOA) have been identified as important allelochemicals in wheat. This study examines the possibility of exploiting the allelopathic properties of wheat as a weed control strategy by cultivating wheat as a precrop and incorporating plant residues into the soil before the next crop is sown. Different wheat varieties were cultivated in field plots during two seasons in both conventional and organic farming systems. Plants were sampled at various growth stages, and their contents of DIMBOA, MBOA, and BOA were determined by chemical analyses. The wheat samples were incorporated into soil, and the effect on germination and growth of 12 different weed species was examined in pot experiments under controlled conditions. In some cases significant effects were obtained, but the results were inconsistent and the effects were not correlated to the content of DIMBOA, MBOA, and BOA in the incorporated wheat plants. ED50 doses of the pure compounds were estimated in dose-response experiments in Petri dishes, and these turned out to be much higher than the predicted maximum concentrations of DIMBOA, MBOA, and BOA in the soil water following incorporation. The study shows that a prerequisite for exploiting the incorporation of wheat residues as a weed control strategy is the development of wheat varieties with an increased content of allelochemicals. 相似文献
85.
86.
Heading behaviour of eight strains of timothy was observed in the sowing and first harvest years, after sowing on a series of dates between March and August.
All strains produced heads in the sowing year. Only a very few plants failed to head when sown between 18 March and 29 April. With subsequent sowing dates the proportion of heading plants progressively declined, most markedly in S.50 Phleum nodosum , least in the early-heading P. pratense strains. No heading occurred in the sowing year after the mid-August sowing.
The environment to which the later sowings are exposed differs from that of the earlier sown lots in that (a) the initial temperatures and daylengths are higher and (b) the decline in daylength occurs earlier in their development. One or both of these factors must be responsible for failure of heading among plants of the later sowings.
The sequence of heading dates among the strains in the sowing year differed considerably from that in the same plants after overwintering, suggesting the action of some factor other than photo-period in determining heading date in the sowing year.
Variability in heading date within the strains was much greater in the sowing year than after overwintering, and increased with lateness of sowing. 相似文献
All strains produced heads in the sowing year. Only a very few plants failed to head when sown between 18 March and 29 April. With subsequent sowing dates the proportion of heading plants progressively declined, most markedly in S.50 Phleum nodosum , least in the early-heading P. pratense strains. No heading occurred in the sowing year after the mid-August sowing.
The environment to which the later sowings are exposed differs from that of the earlier sown lots in that (a) the initial temperatures and daylengths are higher and (b) the decline in daylength occurs earlier in their development. One or both of these factors must be responsible for failure of heading among plants of the later sowings.
The sequence of heading dates among the strains in the sowing year differed considerably from that in the same plants after overwintering, suggesting the action of some factor other than photo-period in determining heading date in the sowing year.
Variability in heading date within the strains was much greater in the sowing year than after overwintering, and increased with lateness of sowing. 相似文献
87.
Longeon A Copp BR Quévrain E Roué M Kientz B Cresteil T Petek S Debitus C Bourguet-Kondracki ML 《Marine drugs》2011,9(5):879-888
Indole derivatives including bromoindoles have been isolated from the South Pacific marine sponges Rhopaloeides odorabile and Hyrtios sp. Their structures were established through analysis of mass spectra and 1D and 2D NMR spectroscopic data. Their potential inhibitory phospholipase A2 (PLA2), antioxidant and cytotoxic activities were evaluated. The new derivative 5,6-dibromo-l-hypaphorine (9) isolated from Hyrtios sp. revealed a weak bee venom PLA2 inhibition (IC50 0.2 mM) and a significant antioxidant activity with an Oxygen Radical Absorbance Capacity (ORAC) value of 0.22. The sesquiterpene aureol (4), also isolated from Hyrtios sp., showed the most potent antioxidant activity with an ORAC value of 0.29. 相似文献
88.
Meggers BJ 《Science (New York, N.Y.)》2003,302(5653):2067-70; author reply 2067-70
89.
Howard L. Bachrach Donald O. Morgan Peter D. McKercher Douglas M. Moore Betty H. Robertson 《Veterinary microbiology》1982,7(2):85-96
Peptide fragments were obtained from the immunogenic capsid protein VP3, ca. 24 kilodaltons (kd), of foot-and-mouth disease virus type A12 119ab by three procedures: (1) spontaneous proteolysis of in virion VP3 in tissue cultures to produce a 15 kd peptide, designated S fragment; (2) trypsin treatment of purified virus to produce a 16 kd peptide, designated T fragment; and (3) cyanogen bromide cleavage of purified VP3 to produce a 13 kd fragment. Following isolation and purification by gel electrophoresis, VP3 and each of the three fragments were immunogenic for livestock. Lyophilization appeared to impair the immunogenicity of VP3. In addition, viruses containing VP3 fragments produced either by the spontaneous- or trypsin-induced proteolysis were as immunogenic as virus with its VP3 intact. Amino acid sequencing of N-terminal regions revealed that the S fragment was homologous with the N-terminus of VP3, whereas the 13 kd fragment possessed a unique N-terminus. Thus, putative common immunogenic amino acid sequences would appear to reside within an overlap region of the 15 kd S and 13 kd fragments. Sequencing of cDNA prepared to viral genome RNA provided three kinds of information: it (1) placed the above overlap region in the second and third quarters of VP3; (2) demonstrated that the codons for the C-terminus of VP1 and N-terminus of VP3 are contiguous; and (3) supported earlier evidence that these same codons program a chain reversal where VP1 and VP3 are joined in the precursor polyprotein. 相似文献
90.
Ge B Gram H Di Padova F Huang B New L Ulevitch RJ Luo Y Han J 《Science (New York, N.Y.)》2002,295(5558):1291-1294
Phosphorylation of mitogen-activated protein kinases (MAPKs) on specific tyrosine and threonine sites by MAP kinase kinases (MAPKKs) is thought to be the sole activation mechanism. Here, we report an unexpected activation mechanism for p38alpha MAPK that does not involve the prototypic kinase cascade. Rather it depends on interaction of p38alpha with TAB1 [transforming growth factor-beta-activated protein kinase 1 (TAK1)-binding protein 1] leading to autophosphorylation and activation of p38alpha. We detected formation of a TRAF6-TAB1-p38alpha complex and showed stimulus-specific TAB1-dependent and TAB1-independent p38alpha activation. These findings suggest that alternative activation pathways contribute to the biological responses of p38alpha to various stimuli. 相似文献