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91.
The objective of this study was to determine the tissue density, in vitro expansion and differentiation of canine adipose tissue-derived (ASC) and bone marrow-derived (BMSC) stromal cells. Primary (P0) and cell passages 1-6 (P1-6) cell doubling numbers (CD) and doubling times (DT) were determined in fresh cells. The P0, P3, and P6 adipogenic (CFU-Ad), osteogenic (CFU-Ob), and fibroblastic (CFU-F) colony forming unit frequencies, lineage specific mRNA levels in differentiated P3 cells and composition of P3 and P6 chondrogenic pellets were assessed in cryogenically preserved cells. Cell yields from bone marrow were significantly higher than adipose tissue. Overall ASC and BMSC CDs and DTs and P3 and P6 CFU-F, CFU-Ad, and CFU-Ob were comparable. The P0 BMSC CFU-Ob was significantly higher than ASC. Lineage specific mRNA levels were higher in differentiated versus control cells, but similar between cell types. Protein was significantly greater in P3 versus P6 ASC chondrogenic pellets. Based on these findings, fresh and revitalized canine ASCs are viable alternatives to BMSCs for stromal cell applications.  相似文献   
92.
93.
A rapid glasshouse‐based bioassay method to screen large numbers of cotton plants for responses to Fusarium oxysporum f. sp. vasinfectum (Fov) was developed. Different Fov inoculum concentrations and methods of inoculation were assessed using resistant and susceptible cotton cultivars. Cotton seeds were planted directly into Fov‐inoculated soil. Studies of seed germination, seedling establishment, seedling mortality and fusarium wilt symptoms (i.e. stunting, foliar symptoms and vascular browning) were performed to optimize the bioassay parameters. Growing seedlings in Fov‐inoculated soils at 5 × 104 or 1 × 105 CFU g?1 soil, in individual seedling tubes with 12 h at 28–30°C and 12 h at 15–18°C, gave consistent results when assessing Fov disease responses 6 weeks after inoculation. When fusarium wilt resistance ranks (FWRRs) and vascular browning index (VBI) means of 18 Australian and other cotton cultivars from the Fov glasshouse bioassay were compared against their fusarium field performance ranks (F‐ranks), assessed on adult plants for cotton cultivar release, Pearson’s correlation was highly significant for both comparisons. The level of congruence between field and glasshouse data indicated that this protocol should be an effective tool for large‐scale screening for Fov‐resistance responses in diverse germplasm and breeding populations and for advancing genetic research to develop molecular markers for Fov resistance in cotton.  相似文献   
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95.
The aim of this work was to analyse the genetic origin of the Mexican Creole donkey, as well as its genetic diversity, by comparison with Spanish and African donkey populations by means of the D-loop region of mitochondrial DNA. To this end, the genomic DNA of 68 Mexican Creole donkeys from eight geographical regions in six States of the Republic of Mexico and from a Sicilian donkey was obtained. By the polymerase chain-reaction technique (PCR) a fragment of 541 bp was amplified, corresponding to the most informative region of the mitochondrial DNA, the D-loop. The fragments were subsequently sequenced. The analysed sequences revealed 10 new Mexican haplotypes that were different from those of the Spanish and African breeds with which they were compared, showing high levels of genetic diversity. Analysis of the phylogenetic relationships in the different Creole varieties showed a tendency of origin towards Spanish breeds, mainly the Andaluza, Zamorano-Leonesa and Majorera from the Canary Islands; these in turn showed an African origin, seven Mexican haplotypes and three haplotypes similar to those analysed by Aranguren and colleagues (2004) of Spanish and African breeds being obtained. This work allows us to reach the preliminary conclusion that the origin of Mexican Creole donkey populations in the different states of the Republic of Mexico is clearly of Iberian origin, the Spanish donkey breed Andaluza being the main one contributing to the populations of the Mexican Creole donkeys, followed by the Spanish breeds Zamorano-Leonesa and Majorera from the Canary Islands, and that the populations possess high levels of genetic diversity.  相似文献   
96.
Fecal 17beta-estradiol and progestogens excretion was monitored in adult, female cheetahs (Acinonyx jubatus; n = 2), ZGG-12301 (born 3 April 1993), gonadotrophin treated and ZGT-3301, (born 19 August 1993), nontreated, for 120 days using commercially available plate enzyme immunoassay kits prepared for human serum or plasma. There were significant differences (P < 0.001) between baseline and peak concentrations of both hormone measures. Female ZGG-12301, which conceived, but this pregnancy resulted in an unobserved spontaneous abortion, showed no significant difference (P > 0.05) between baseline and gestation 17beta-estradiol values; fecal 17beta-estradiol excretion during pregnancy was statistically different (P < 0.001) from excretion during the nonpregnancy period. Baseline progestogen concentrations were different from pregnancy (P < 0.001) and postovulatory (P < 0.01) concentrations, and progestogen concentrations during pregnancy period were different (P < 0.001) from postovulatory concentrations. In the nontreated cheetah (ZGT-3301), basal and increased progestogen concentrations were statistically different (P < 0.01). On the basis of 17beta-estradiol excretory patterns, duration of the estrous cycle (x +/- SEM) was 13.2 +/- 2.2 days. These results suggest that the enzyme-linked immunosorbent methods reported in this study were capable of quantifying reproductive hormones in fecal extracts of cheetahs and could be a practical alternative to other enzyme-linked immunosorbent assays which require more complex procedures.  相似文献   
97.
An experimental study was carried out in order to evaluate the regeneration capacity of the neonatal intestinal wall in ischaemia and its repercussion over organs of the immune system such as the spleen. We isolated a reservoir of small intestine in adult Sprague-Dawley rats that, after having been everted and placed at a subcutaneous level, was grafted with a free small intestine segment of neonatal Sprague-Dawley rats and analysed 3, 15 and 30 days after grafting. Samples obtained were stained with Martin's trichromic stain and studied at the light microscopic level. A total regeneration of the crypt architecture, formed by absorptive enterocytes, was observed in the interior of the reservoirs. A quantitative immunohistochemical study with monoclonal antibodies against CD4, CD8, MHC I and MHC II was carried out in the spleen of these animals. An additional immunohistochemical study was also performed in the small intestine reservoirs and spleen of transplanted animals using nitric oxide synthase (NOS) antibodies. Three days after transplantation NOS immunoreactive cells were observed in the reservoirs with transplanted neonatal small intestine. Antigenic stimulation produced, in the spleen red pulp of transplanted animals, a significant increase (P < 0.001) in the percentage of NOS, CD8 and MHC I immunoreactive cells in relation with values observed in control animals. These morphometric changes could be related with the stimulation that nitric oxide produces in the proliferation of the cytotoxic T cells.  相似文献   
98.
Based on current literature which commonly associates bovine virus diarrhea virus and Mycoplasma bovis with "pneumonic pasteurellosis," an investigation was conducted into the effect of these two pathogens on the capacity of bovine lung to clear inhaled Pasteurella haemolytica. There was no significant effect (p less than 0.05) of either bovine virus diarrhea virus or M. bovis on the mean clearance rate of P. haemolytica, nor did the time interval of three, five or seven days between the first inoculation and exposure to P. haemolytica and adversely affect the lung clearance rates. However, it was found that the left lungs and a higher bacterial retention (p less than 0.05) than the right lungs.  相似文献   
99.
100.
Results of commercially available diagnostic test kits and commercial laboratory test results were compared for ability to detect FeLV antigen. Results of the immunofluorescent antibody (IFA) test were compared with test kit ELISA results and with results of a system in which samples were applied to an absorbent material, dried, sent to a laboratory, eluted, and assayed by a plate ELISA. Test kits were generally highly sensitive and specific, compared with the IFA test performed at a commercial laboratory. Feline heterophile antibody, specific for mouse immunoglobulin, was detected in approximately 0.14 to 0.57% of the cat population. Test kits B, E, and D contain reagents that correct for antimouse antibodies. During 1989 and 1990, 2,229 feline serum samples were tested for FeLV antigen (gsa p27); positive ELISA results were obtained for 204 (9%) of the samples. Results for 32 (1.4%) samples were interpreted as equivocal (color development slightly exceeded that of the negative control, but was much less than that of the positive control). Collectively, the data indicate that when testing serum or saliva, a negative test result may be a good predictor that a cat is not infected. In populations of cats in which FeLV prevalence is low, a positive test result may not be reliable and thus, a confirmatory test should be performed.  相似文献   
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