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551.
Soluble nymphal antigens (HNAg) were purified by immunoaffinity chromatography using CNBr-activated Sepharose 4B coupled with immunoglobulin ligands from animals immunized with HNAg and 69–71% protected against challenge infestations, and 8% recovery of the purified protein (Aff-HNAg) was obtained. Following immunization of crossbred calves (Bos indicus×Bos taurus) with 1600 g of Aff-HNAg in three divided doses, significant rejections of larvae (p<0.001, 84.2%), nymphs (p<0.05, 61.4%) and adults (p<0.05, 58.7%) were recorded. No significant changes were recorded in the engorgement weights of the larvae and nymphs, but there was a significant (p<0.05) reduction in the weight of the engorged adults. Immunization conferred a significant decrease in the numbers of resultant nymphs (p<0.001) and adults (p<0.001) that had fed on the immunized animals. SDS-PAGE analysis identified a 39 kDa protein, previously isolated from larvae of Hyalomma anatolicum anatolicum, as the antigen responsible for the induction of resistance against all the stages of the tick.  相似文献   
552.
An attempt was made to determine plasma concentrations of, 13, 14‐dihydro‐15‐keto‐prostaglandin F (PGFM), cortisol and progesterone during periparturient period in yak. Plasma PGFM level showed an increasing trend beginning day 5 prior to parturition (0.48 ± 0.14 ng/ml) and increased steeply thereafter to reach a peak level (17.16 ± 1.31 ng/ml) on the day of parturition. The levels, then, declined sharply on day 1 postpartum to reach 1.20 ± 0.40 ng/ml and thereafter declined gradually over the days to reach 0.28 ± 0.09 ng/ml on day 20 postpartum and this level was maintained with fluctuation within narrow limits thereafter till conclusion of the blood sampling on day 90 post‐calving. The plasma progesterone concentration on days 7 and 6 before parturition was high (2.10 ± 0.10 and 2.12 ± 0.10 ng/ml, respectively). The level then decreased gradually and abrupt fall was observed 1–2 days before parturition and became basal on day of parturition (0.24 ± 0.04 ng/ml). This basal level was maintained till the end of the blood sampling on day 90 postpartum. Plasma cortisol level showed an increasing trend beginning day 2 prior to parturition (2.36 ± 0.65 ng/ml) and increased steeply thereafter to reach a peak level (26.65 ± 5.28 ng/ml) on the day of parturition. The levels, then, declined gradually over the days and touched 2.36 ± 0.25 ng/ml on day 3 postpartum and this level was maintained with fluctuation within narrow limits thereafter till day 7 post‐calving.  相似文献   
553.
Pharmacologic inhibition of autophagy can be achieved using lysosomotropic agents such as hydroxychloroquine (HCQ) that interfere with fusion of the autophagosome to the lysosome thus preventing completion of the recycling process. The goal of the present study is to determine the sensitivity of eight canine (cOSA) and four human (hOSA) osteosarcoma tumour cell lines to antiproliferative and cytotoxic effects of lysosomal autophagy inhibitors, and to compare these results to the autophagy-dependence measured using a CRISPR/Cas9 live-cell imaging assay in OSA and other tumour cell lines. Antiproliferative and cytotoxic response to HCQ and Lys05 was determined using live cell imaging and YOYO-1 staining. CRISPR/Cas9 live cell imaging screen was done using species specific guide RNA's and transfection of reagents into cells. Response to autophagy core genes was compared to response to an essential (PCNA) and non-essential (FOXO3A) gene. cOSA and hOSA cell lines showed similar antiproliferative and cytotoxic responses to HCQ and Lys05 with median lethal dose (Dm) values ranging from 4.6–15.8 μM and 2.1–5.1 μM for measures of anti-proliferative response, respectively. A relationship was observed between antiproliferative responses to HCQ and Lys05 and VPS34 CRISPR score with Dm values correlating with VPS34 response (r = 0.968 and 0.887) in a species independent manner. The results show that a subset of cOSA and hOSA cell lines are autophagy-dependent and sensitive to HCQ at pharmacologically-relevant exposures.  相似文献   
554.
Journal of Pest Science - The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is a highly destructive insect pest of several crop plants and threatening global food security. The current...  相似文献   
555.
It is mandatory to assess the allergenic potential of genetically modified (GM) crops before their commercialization. Recently, a transgene [Calcineurin B-like (CBL) protein] has been introduced into tobacco plant to make the crop salt resistance. Therefore, it was felt necessary to assess the allergenic potential of the cbl gene product, which was introduced and expressed in Nicotiana tabacum (tobacco) plant and compared the allergenic effects with the wild-type (WT) counterpart. Bioinformatic analysis revealed that there was no significant sequence homology with known allergens. Also, no difference between the protein digestibility profiles of GM and WT tobacco was found. Rapid digestion of CBL protein (Mol Wt 35 kDa) by simulated gastric fluid (SGF) indicated reduced chances of this protein to induce allergenicity. In addition, BALB/c mice sensitized by intraperitoneal administration of WT and GM tobacco protein showed comparable levels of clinical score, specific IgE, IgG1, histamine level, similar effect on different organs as well as IgE binding proteins. These findings indicate that insertion of cbl gene in tobacco did not cause any additional allergic risk to consumer and the GM and native tobacco proteins behave similarly in both in vitro and in vivo situations even after genetic modification.  相似文献   
556.
The primary objective of this study was to develop a simplified, rapid and authenticated protocol for sexing of caprine embryos. Polymerase chain reaction (PCR) is a powerful tool in preimplantation sex diagnosis, using embryo biopsy at the early developmental stage. Based on the amelogenin gene located on the conserved region of the sex chromosome, a primer pair was used and PCR was established to amplify a 262-bp fragment from the Xchromosome in female goat embryos and 262-bp fragments from the X chromosome and 202-bp fragments from the Y chromosome in male embryos. To validate the reliability of PCR, using the sex-determining region Y (SRY) gene located on the conserved region of Y chromosome, a primer pair was used and PCR was established to amplify a 122-bp fragment specific to the Y chromosome in male embryos. The in vitro-produced goat in vitro fertilisation (IVF)-embryos were made zona free by treating with pronase. The cell number in each embryo was counted before sexing. A single blastomere taken from these embryos was directly used as a template in PCR containing SRY and amelogenin gene-specific primers separately. Of 75 pronase-treated and 60 micromanipulated goat IVF embryos, 33 (44%) and 26 (43.33%) were confirmed as male and 42 (56%) and 34 (56.66%) as female, respectively. The sex-diagnosed embryos were kept in research vitro cleavage (RVCL) medium, and developed into 42.66% and 61.66% morulae and 13.33% and 23.33% blastocysts among pronase-treated and micromanipulated embryos, respectively. The AMELX gene-specific primer served as the internal control and did not interfere with amplification of the Y-specific sequence. In conclusion, a single blastomere sexing protocol based on the SRY and the amelogenin gene is simple, rapid, sensitive and efficient for sex determination in caprine early stage embryos.  相似文献   
557.
558.
The present study assessed the mineral status of pigs fed with local feed resources. The commonly used plants for feeding pigs and blood serum samples from Hampshire, Large White Yorkshire and indigenous pigs were analyzed for total protein, albumin and cholesterol levels. Processed plant and serum samples were also analyzed for calcium, phosphorus, magnesium, sodium, potassium, copper, cobalt, manganese, iron and zinc. The incidence and extent of mineral deficiency in pigs was quantified. No significant difference was observed in total protein and albumin levels between any two breed/types of pigs, however the Indigenous pigs showed significantly (P < 0.05) higher cholesterol level compared to other two breeds. Among different plants, Spilanthus sp had majority of macro and micro nutrients in high levels. Regarding incidence of mineral deficiency in pigs, it was observed that 90, 67.1, 61.4, 48.6, 95.7% of the pigs were deficient in calcium, phosphorus, sodium, magnesium and potassium. An interesting finding was that all the pigs (100%) utilized in the study were deficient in zinc. From this study, it was inferred that there are good numbers of potential source of mineral that might be used more economically to improve the mineral availability to pigs.  相似文献   
559.
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