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91.
A 13-year-old spayed mixed-breed dog was diagnosed with a gastrointestinal stromal tumor (GIST) after histopathological examination of an abdominal mass. Five months after surgical resection of the tumor, we detected the recurrence of GIST with multiple disseminated abdominal lesions. A sequence analysis of cDNA obtained from a biopsy of the recurrent tumors revealed a mutation within exon 9 of the c-kit gene (1523A>T, Asn508Ile), which has been shown to cause ligand-independent phosphorylation of the KIT protein in GISTs and canine mast cell tumors (MCTs). Upon detection of the recurrent tumors, we initiated treatment with imatinib mesylate (10 mg/kg, q 24 hr). After 2 months, the dog achieved complete remission. Our findings indicate that canine GIST, and possibly MCT, may be responsive to molecular-targeted therapy.  相似文献   
92.
Swim bladder tumors were detected in three out of 28 wavy medakas aged about 2 years old, all of which displayed abnormal swimming patterns caused by their spinal curvature. The tumors were located in the dorsal abdominal cavity. The swim bladder lumen was not detected in the region where it was originally assumed to be located, and that region was replaced with adipose tissue. The tumors were non-invasive, expansile, and encapsulated solid masses composed of a homogenous population of well-differentiated, densely packed, gas glandular epithelium-like cells. The tumor masses were connected to the rete mirabile, but the tumor cells did not infiltrate into them. Histopathologically, these tumors were diagnosed as adenomas originating from the gas glandular epithelium of the swim bladder. Spontaneous swim bladder tumors are rare in medaka, with an incidence of 0.02%; however, in the present study of wavy medaka, the incidence was much higher (10.7%). The long-term physical effects on the gas gland caused by swim bladder deformation considered to be a secondary effect of the spinal curvature may be an important factor in the proliferation of the gas glandular epithelium in the wavy medaka, resulting in the higher incidence of swim bladder tumors.  相似文献   
93.
T cell‐mediated cellular immunity and humoral immunity are equally important for the prevention of diseases. To assess activation of human and mouse cellular immunity, early activation markers of lymphocytes are often used in flow cytometry targeting expression of CD69 molecules. Response of humoral immunity against infection or vaccination has been well investigated in pigs, but that of cellular immunity has been largely neglected due to lack of direct evaluation tools. Thus, in pig research a proper assay of antibody reacted with porcine CD69 is still unavailable. In the present study, two anti‐porcine CD69 mAb‐producing mouse hybridomas, 01‐14‐22‐51 (IgG2b–κ) and 01‐22‐44‐102 (IgG2a–κ), both showing fine reactivity with phorbol 12‐myristate 13‐acetate (PMA) and ionomycin‐stimulated porcine peripheral blood lymphocytes in flow cytometry, were established. When porcine peripheral blood lymphocytes were activated with PMA and ionomycin and analyzed by flow cytometry, it was found that both mAbs generated in this study stained about 70% of lymphocytes. In contrast, after an identical procedure, only 5% and 13.5% of lymphocytes were stained with anti‐interferon‐γ mAb and anti‐tumor necrosis factor‐α mAb, respectively. These results indicate that evaluation of cellular immunity activation turns more sensitive after using our newly generated mAbs.  相似文献   
94.
The elite indica rice variety Hua-jing-xian 74 and its 12 single segment substitution lines (SSSLs), all of which have been shown to have quantitative trait loci (QTL) for panicle number (PN), were used as crossing parents to construct a half-diallel crossing population with the aim of analyzing the expression of these QTL under different cropping densities. A total of 91 half-diallel crossing combinations were grown in two planting seasons at three cropping densities. PN was measured at the mature stage. The additive, dominant and epistatic effects of the 12 QTL as well as their interaction effects with the seasons and with the densities were estimated based on genetic effect components. Our analysis revealed that PN generally decreased with increasing cropping density. In the six single environments, eight additive QTL, nine dominant QTL and 49 pairs of epistatic QTL were detected, which were mostly associated with estimated positive, positive and negative effects, respectively. Expression of these QTL differed across planting seasons and cropping densities, implying an existing of QTL-by-environment interaction. Further analysis of the QTL effect components revealed that seven, eight and 28 pairs of QTL were present with significant additive, dominance, epistasis and/or interaction effects with densities. QTL additive and dominant effects were mostly positive, while epistatic effects were all negative. No significant QTL-by-season effects were detected. QTL Pn3-1, without any significant additive-by-density interaction effect, showed stable additive expression across densities. QTL Pn3-1, Pn3-2 and Pn6-1 showed stable dominance expression, and QTL pairs Pn2-1/Pn9, Pn2-2/Pn3-1, Pn2-2/Pn6-2, Pn3-1/Pn6-1, Pn3-1/Pn7 and Pn6-1/Pn6-3 had stable epistasis expression. The remaining significant QTL had different effects across densities. We determined that a density of 10 × 16.7 cm2 had little influence on QTL expression, that a density of 16.7 × 16.7 cm2 mostly increased QTL additive and dominant effects and decreased QTL epistatic effects and that a density of 23.3 × 16.7 cm2 had the opposite impact on QTL effects compared with 16.7 × 16.7 cm2. Additionally, the influence of density on QTL epistatic effect was generally larger than that on QTL additive or dominant effect. These results provide the information on cropping density and how it influences PN QTL expression, which may be useful information to improve rice PN via heterosis and/or QTL pyramiding.  相似文献   
95.
The metabolism of grape seed polyphenol (GSP) has been investigated in rats by high-performance liquid chromatography analysis of the serum and urinary concentrations of the GSP metabolites (+)-catechin (CT), (-)-epicatechin (EC), 3'-O-methyl-(+)-catechin, and 3'-O-methyl-(-)-epicatechin. The serum concentration of these four metabolites reached a maximum 3 h after the oral administration of GSP. The urinary excretion of these GSP metabolites accounted for 0.254% (w/w) of the administered dose of GSP (1.0 g/kg), and the majority of these metabolites were excreted within 25 h of oral administration. The serum concentration and urinary excretion of these metabolites were also compared after the oral administration of different GSP monomers (gallic acid, CT, and EC), normal GSP, and the high molecular weight components of GSP (GSPH). No metabolites were detected in the serum of rats given GSPH. The urinary percentage excretion of the GSP metabolites derived from the respective monomers (CT or EC) did not vary with the administration of different substances (CT or EC, GSP, or GSPH). Taken together, these results suggest that only the monomers of GSP are absorbed and metabolized.  相似文献   
96.
While silicon (Si) fertilization is widely practiced in rice production, establishing critical soil Si levels has remained understudied. Field trials were established at 12 sites across Louisiana from 2013 to 2015 to determine critical soil Si for rice cultivation. Five silica slag (14% Si) rates at 0, 1, 2, 4, 6, and 8 Mg ha?1 and two lime rates (2 and 4 Mg ha?1) were arranged in randomized complete block design with four replications. Post harvest soil samples were analyzed for Si using seven extraction procedures. The critical soil Si levels established by the linear plateau model using 0.5 M acetic acid-1 hr (OAc-1) extraction procedure were 36, 41 and 50 mg kg?1 for plant Si uptake, grain yield, and relative yield as response variables, respectively. Generally, soils having high initial Si and pH had minimal responses to Si fertilization, whereas Si content of soils with low initial Si was significantly increased.  相似文献   
97.
Nitrogen and carbon dynamics in paddy and upland soils for rice cultivation and in upland soil for corn cultivation was investigated by using 13C and 15N dual-labeled cattle manure compost (CMC). In a soil with low fertility, paddy and upland rice took up carbon and nitrogen from the CMC at rates ranging from 0.685 to 1.051% of C and 17.6–34.6% of N applied. The 13C concentration was much higher in the roots than in the plant top, whereas the 15N concentration differed slightly between them, indicating that organic carbon taken up preferentially accumulated in roots. The 13C recovery in the plant top tended to be higher in upland soil than in paddy soil, whereas 15N applied was recovered at the same level in both paddy and upland soils. In the experiment with organic farming soil, paddy rice took up C and N from the CMC along with plant growth and the final recovery rates of 13C and 15N were 2.16 and 17.2% of C and N applied. In the corn experiment, a very large amount of carbon from the CMC was absorbed, accounting for at least 7 times value for rice. The final uptake rates of 13C and 15N reached about 13 and 10% of C and N applied, respectively. Carbon emission from the CMC sharply increased by 2 weeks after transplanting and the nitrogen emission was very low. It is concluded that rice and corn can take up an appreciable level of carbon and nitrogen from the CMC through roots.  相似文献   
98.
Two new triterpene benzoates, 5-dehydrokarounidiol dibenzoate (1) and karounidiol dibenzoate (2), and two new triterpene glycosides, 5alpha,6alpha-epoxymogroside IE(1) (8) and 11-oxomogroside A(1) (9), along with 15 known triterpenoids (one triterpene benzoate, 3; three triterpene mono-ols, 4-6; one triterpene aglycon, 7; and 10 triterpene glycosides, 10-19), were isolated from the ethanol extract of the fruit of Momordica grosvenori. The structures of 1, 2, 8, and 9 were determined on the basis of spectroscopic and chemical methods. Among the known triterpene glycosides, mogroside I E(1) (12) was a new naturally occurring compound. Eighteen triterpenoids (2-19) and 11-oxomogrol (20), a hydrolysis product of 9, were evaluated with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, which is known to be a primary screening test for antitumor promoters. All of the compounds tested showed potent inhibitory effects on EBV-EA induction (70-100% inhibition at 1 x 10(3) mol ratio/TPA).  相似文献   
99.
The effects of non-ionic (sorbitol, maltose, trehalose) and ionic compounds (Na-glutamate, Na-acetate, Na-sulfate, ammonium sulfate) on freeze denaturation of myosin subfragment-1 (S-1) and of myofibrils were compared. Sugars, Na-glutamate and Na-acetate well suppressed the freeze denaturation of myofibrils as well as S-1 in a concentration dependent manner. Although sulfate suppressed freeze denaturation of S-1 irregularly, it accelerated myofibril denaturation. It was concluded that sulfate salts were useless as cryoprotectant for myofibrils. Stabilization extent by F-actin in frozen storage was much less than that in heating.  相似文献   
100.
Morphological features of Pacific bluefin tuna Thunnus orientalis have important functions for its fast swimming. Morphological features of tuna change with growth; therefore, morphological functions may develop during this process. In this study, we precisely quantified the morphology of bluefin tuna with growth from juvenile to young adult using a three-dimensional laser profiler and evaluated the fluid dynamic characteristics of tuna using computational fluid dynamics (CFD) and an accurate model based on measured data. As results of measurement of morphological features, the aspect ratio and sweepback angle, which are indices of hydrodynamic characteristics for a hydrofoil, suggested that the lift force of caudal fin was increased as the tuna grows. The results of CFD analysis showed that the coefficient of drag force gradually decreased with growth. Pectoral fins generated lift force, and the ratio of lift force to submerged weight (FL/SW) increased as the tuna grew to 0.2 m total length (TL). After the tuna exceeded 0.2 m TL, FL/SW changed to a wider range in angle of attack as the tuna grew. These results suggest that the morphological function of bluefin tuna develops to enhance its swimming ability as it grows from juvenile to young adult.  相似文献   
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