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51.
52.
Nezara viridula (L.) (Hemiptera: Pentatomidae), commonly known in the U.S. as the southern green stink bug (SGSB), is a cosmopolitan, highly polyphagous feeder that causes severe damage to a wide range of agronomically important crops such as fruit, vegetable, grain, tobacco, and cotton, throughout much of the United States, and is a global pest of considerable ecological, agricultural, and economical interest. During dissection of female Nz. viridula, conspicuous black and brown spots or lesions were observed on various internal organs. To determine the cause of these spots or lesions, tissues of fat body, spermatheca, ovaries, and ovulated eggs were collected from healthy and infected individuals. The gross morphology of the spots was characterized, and the microorganisms associated with the infection were identified by amplicon sequencing of the V4 region of the small subunit rRNA gene. The presence of a microsporidian pathogen Nosema maddoxi, Becnel, Solter, Hajek, Huang, Sanscrainte, & Estep (Microsporidia: Nosematidae) which has been observed on other species of stink bug, was evidenced for the first time. The characterization of the gross morphology of this associated microsporidian may enable more rapid determination of microsporidia infection in stink bug colonies and field populations.  相似文献   
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The aim was to evaluate the antineoplastic potential of a previously characterized peptide extract from the non-digestible fraction of common bean cv. Azufrado Higuera (AH) and its most abundant pure peptide GLTSK, in an azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colitis-associated colon carcinogenesis Balb/c mice model. The healthy control (C-) had no induction and no treatment, and the induced control (C+) had induction but no treatment. Groups AH and GLTSK were administered 50 mg/kg-bw of AH or GLTSK, respectively. The administration of AH and GLTSK decreased (p < 0.05) the disease activity index (DAI) compared to C+ (5.8, 9.1, 11.8, respectively). Furthermore, AH reduced the number of evident neoplasms compared to group C+ (1.8, 5.9 neoplasms/mice, respectively). The results suggest that peptides from common bean cv. Azufrado Higuera could prevent colitis-associated colon carcinogenesis.  相似文献   
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Seroprevalence of Toxoplasma gondii was tested for in 585 cats in different regions of Spain. Sera were tested by the indirect immunofluorescence antibody test (IFAT). Specific antitoxoplasma IgG (IFAT titer>or=1/80) were found in 189 of 585 (32.3%): 117 of 317 (36.9%) stray cats, 16 of 48 (33.3%) farm cats and 56 of 220 (25.5%) household cats. The overall prevalence was significantly higher in stray groups (36.4% of 365) than in household cats (25.5% of 220), higher in adult cats (>6 months old, 36.8% of 443) than in juvenile cats (<6 months old, 13.9% of 101), and higher in male stray cats (45.3% of 128) than in female stray cats (32% of 153). Prevalence of intestinal parasites was also analysed by a routine coprological method in 382 of the 585 cats. Intestinal parasites were found in 107 faecal samples (28%): 76 of 231 (32.9%) stray cats, 14 of 48 (29.2%) farm cats and 17 of 103 (16.5%) household cats. T. gondii oocysts were not found in any faecal samples analysed. The following prevalences of other intestinal parasites were found: Toxocara cati (18.3%), Toxascaris leonina (1.3%), Ancylostoma sp. (1%), Capillaria spp. (1.3%), Aelurostrongylus abstrusus (1%), Taenia like (3.7%), Dipylidium caninum (2.6%) and Cystoisospora spp. (6.3%).  相似文献   
55.
Samples of semen from 12 pigs, three from Yorkshire, Landrace, Duroc and Mexican Hairless each where obtained to study cryopreservation methods. Three stages of boar semen cryopreservation were evaluated: none (fresh stage), cooling at 5 degrees C and freezing at -196 degrees C then thawing to 56 degrees C for 12 sec. Perinuclear theca damage and domain alterations were selected as indices of seminal quality, as measured by electronic and fluorescence microcopy, respectively according to two lineal models considering by separately the effect of semen preservation and breed. Integrity and absence of perinuclear theca significantly (p < 0.001) decreased and increased, respectively according to a decrease in temperature of cryopreservation, from 87.4 to 58.8% and from 0.8 to 26.2%, respectively. This same significant (p < 0.001) effect was found for acrosomal and post-acrosomal membrane distribution of domains, from 92.1 to 76.8% and from 3.1 to 13.1% in this same order. Slight but highly significant (p < 0.001) differences were observed when theca integrity was evaluated as affected by breed, with highest and lowest values for Yorkshire and Pel6n Mexicano pigs, respectively. No breed effect was encountered for presence of acrosomal domains. A strong interdependence was found between perinuclear theca damage and domain distribution. In this connection, a highly significant (p < 0.001) positive, interdependence was observed between the theca damage and acrosomal domain (r = 0.87), while this same relationship was although highly significant (p < 0.001), negative in nature for equatorial and post-acrosonal domains (r = -0.77 and -0.85, respectively). This experiment confirmed that cryopreservation methods may severely affect semen quality of pigs and that genotype may further influence these same indices. More research is needed for improving methods of preservation of pig semen quality, from the point of view of perinuclear theca and domain characteristics of spermatozoa.  相似文献   
56.
Major phenotypic changes evolve in parallel in nature by molecular mechanisms that are largely unknown. Here, we use positional cloning methods to identify the major chromosome locus controlling armor plate patterning in wild threespine sticklebacks. Mapping, sequencing, and transgenic studies show that the Ectodysplasin (EDA) signaling pathway plays a key role in evolutionary change in natural populations and that parallel evolution of stickleback low-plated phenotypes at most freshwater locations around the world has occurred by repeated selection of Eda alleles derived from an ancestral low-plated haplotype that first appeared more than two million years ago. Members of this clade of low-plated alleles are present at low frequencies in marine fish, which suggests that standing genetic variation can provide a molecular basis for rapid, parallel evolution of dramatic phenotypic change in nature.  相似文献   
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58.
We have previously demonstrated that the non-digestible fraction (NDF) from common cooked beans (P. vulgaris L., cv Negro 8025) inhibits azoxymethane (AOM)-induced colon cancer and influences the expression of genes involved in the induction of apoptosis and cell cycle arrest through the action of butyrate. The objective of this study was to identify cell cycle alterations and morphological changes induced by treatment with AOM and to examine the formation of colonic aberrant crypt foci (ACF) in male Sprague Dawley rats fed with these beans. Rats were fed control diets upon arrival and were randomly placed into four groups after one week of acclimatization: control, NDF (intragastric administration), NDF?+?AOM and AOM. Rats treated with NDF?+?AOM exhibited a significantly lower number of total colonic ACF with a notable increase in the number of cells present in the G1 phase (83.14 %); a decreased proliferation index was observed in the NDF?+?AOM group when compared to AOM group. NDF?+?AOM also displayed a higher number of apoptotic cells compared to AOM group. NDF of cooked common beans inhibited colon carcinogenesis at an early stage by inducing cell cycle arrest of colon cells and morphological changes linked to apoptosis, thus confirming previous results obtained with gene expression studies.  相似文献   
59.
Different strategies were adopted to achieve increases in color stability in Tempranillo wines: (i) addition of maceration enzymes directly to the must, (ii) addition of commercial mannoproteins to the must, and (iii) inoculation of must with yeast overexpressed of mannoproteins. The addition of enzymes favored color extraction, and the wines obtained presented higher values of wine color, color intensity, bisulfite-stable color, and visually enhanced color intensity. The enzyme hydrolytic activity produced an increase in the acid polysaccharide content and polyphenol index and yielded to wines with more astringency, tannin, and length. Added mannoproteins had clearer effects on the analyzed parameters than yeast. Contrary to what may be thought, mannoproteins did not maintain the extracted polyphenols in colloidal dispersion and neither ensured color stability. These compounds clearly modified the gustative structure of the wines, enhancing the sweetness and roundness.  相似文献   
60.
We report for the first time the antioxidant and antimutagenic activities of fractions from Randia echinocarpa fruit, which is a Rubiaceae plant native to Sinaloa, Mexico. This fruit has been traditionally used in the prevention or treatment of cancer, among other diseases. The pulp of the fruit was sequentially extracted with solvents of different polarity (i.e. hexane, chloroform, methanol and water). A high extraction yield was obtained with methanol (72.17% d.w.). The aqueous extract showed the highest content of phenolics (2.27 mg/g as ferulic acid equivalents) and the highest antioxidant activity based on the β-carotene bleaching method (486.15). The commercial antioxidant BHT was used as control (835.05). Antimutagenic activity of the aqueous extract (0–500 μg/tube) was evaluated using the Salmonella microsuspension assay (YG1024 strain) and 1-NP as the mutagen (50 and 100 ng/tube). The aqueous extract was neither toxic nor mutagenic and the percentage of inhibition on 1-NP mutagenicity was 32 and 53% at doses of 50 and 100 ng/tube, respectively. The results of the double incubation assay suggest that the extract inhibited the mutagenicity of 1-NP by a combination of desmutagenic and bioantimutagenic effects.  相似文献   
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