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981.
982.
Receptor tyrosine kinases are key regulators of cellular growth and proliferation. Dysregulations of receptor tyrosine kinases in cancer cells may promote tumorigenesis by multiple mechanisms including enhanced cell survival and inhibition of cell death. Araguspongines represent a group of macrocyclic oxaquinolizidine alkaloids isolated from the marine sponge Xestospongia species. This study evaluated the anticancer activity of the known oxaquinolizidine alkaloids araguspongines A, C, K and L, and xestospongin B against breast cancer cells. Araguspongine C inhibited the proliferation of multiple breast cancer cell lines in vitro in a dose-dependent manner. Interestingly, araguspongine C-induced autophagic cell death in HER2-overexpressing BT-474 breast cancer cells was characterized by vacuole formation and upregulation of autophagy markers including LC3A/B, Atg3, Atg7, and Atg16L. Araguspongine C-induced autophagy was associated with suppression of c-Met and HER2 receptor tyrosine kinase activation. Further in-silico docking studies and cell-free Z-LYTE assays indicated the potential of direct interaction between araguspongine C and the receptor tyrosine kinases c-Met and HER2 at their kinase domains. Remarkably, araguspongine C treatment resulted in the suppression of PI3K/Akt/mTOR signaling cascade in breast cancer cells undergoing autophagy. Induction of autophagic death in BT-474 cells was also associated with decreased levels of inositol 1,4,5-trisphosphate receptor upon treatment with effective concentration of araguspongine C. In conclusion, results of this study are the first to reveal the potential of araguspongine C as an inhibitor to receptor tyrosine kinases resulting in the induction of autophagic cell death in breast cancer cells.  相似文献   
983.
984.
Scale insects in Syria were surveyed between 2009 and 2015. This study showed that Diaspididae and Coccidae were the most common families, comprising 5 and 8 species, respectively. The remaining families found comprised 1 species each. New records of Coccoidea fauna from Syria were Parlatoria blanchardi, Phoenicococcus marlatti, Coccus hesperidum, Coccus pseudomagnoliarum and Chionaspis etrusca.  相似文献   
985.
986.
The effect of Bio‐Mos incorporated into feed formulation on the growth, feed utilization, body composition and histological response of sea bass (Dicentrarchus labrax) was investigated. Final fish weight, feed conversion ratio (FCR), specific growth rate (SGR), protein efficiency ratio (PER), protein productive value (PPV) and energy utilization (EU) of sea bass feed Bio‐Mos supplemented diet and the control diet were determined at the end of experiment. Data present mean ± SD from triplicate determination (n = 3) for a 75‐day feeding trial. Different concentrations (0.5, 1.0, 2.0. 3.0 and 4.0 g kg diet?1) of Bio‐Mos supplementation and a control without Bio‐Mos incorporation were fed to the fish, feed in the form of dry diets. Average final weight was significantly higher at 1.0 g kg diet?1 of Bio‐Mos and lowest in control fish group; SGR significantly higher at the 1.0 g kg diet?1 of Bio‐Mos. In addition,, PER, PPV and EU showed the same trend. The chemical body composition, crude protein, dry matter, crude fat and ash were significant (P ≤ 0.01) compared to control groups. We concluded that 1.0 g kg diet?1 of Bio‐Mos improved the growth, feed efficiency, histology intestine and survival of sea bass.  相似文献   
987.
The study was conducted to evaluate the efficiency of echnicacea (E) and garlic (G) supplemented diets as immunostimulant for tilapia (Oreochromis niloticus). Seven treatments were designed including a control (C). Fish were fed on 35% protein diet at a rate of 3% body weight per day. Echinacea (1.0 ppt) and garlic (3%) were incorporated in the feed, which was administered for periods of 1, 2 and 3 months (summer season), followed by basal diet for 4 more months (winter season). Neutrophil adherence and haematocrit values increased in both supplemented groups with prolonging period of application. The neutrophils adherence was significantly increased in all treatments except group administered echinacea for 1 month. The lymphocytic counts were significantly (p < 0.004) elevated that resulted in a significant increase in the total leucocytic count in groups administered echinacea for 1 and 2 months when compared with the control and/or other treatments. The gain in the body weight and specific growth rate was significantly increased in all supplemented groups (p < 0.004) during summer, but remained without any significant increase after winter. The survival rate was significantly high (>85%) in all the supplemented groups. The percentage of protection, after challenge infection using pathogenic Aeromonas hydrophila was the highest in groups supplemented with echinacea and garlic for 3 months after summer and winter seasons. It could be concluded that echinacea and garlic improve the gain in body weight, survival rate and resistance against challenge infection. Both compounds showed extended effects after withdrawal and improved resistance to cold stress during the winter season. However, a full commercial cost benefit analysis is necessary before recommending their application in aquaculture.  相似文献   
988.
Lecithin cholesterol acyltransferase (LCAT) activity was measured in 48 Egyptian water buffaloes four weeks pre-parturient. The activity was significantly low in 37 buffaloes (77.1%). Four weeks post-partum, clinical examination revealed that 23 buffaloes had the clinical signs of ketosis (K) while 14 had the clinical signs of parturient-haemoglobinuria (PHU). Serum samples were collected from 5 buffaloes of each group (K and PHU) besides 5 clinically healthy buffaloes with normal LCAT (control). Glucose level was significantly reduced in K and PHU groups while the phosphorous (P) level was significantly reduced in PHU group compared to control. There were significant reductions in the total cholesterol, free cholesterol, triglycerides, total protein and albumin in K and PHU groups; whereas, significant increases in AST, GGT, non-esterified fatty acids (NEFA) and beta-hydroxybutyric acid (BHBA) in K and PHU groups were detected. Therefore, LCAT could be a predictor for metabolic disorders in Egyptian water buffaloes.  相似文献   
989.
Twenty-one male growing lambs aged 6 months with an average weight 27.6 ± 0.24 kg were used to determine the effects of partial replacing yellow corn with potato processing waste (PPW) on performance of Ossimi lambs. Animals divided into three equal groups and assigned for control and two experimental diets containing PPW which was replaced from yellow corn at 0% PPW (R1), 25% PPW (R2), and 50% PPW (R3). The results showed that tested rations were almost isocaloric and isonitrogenous. Dietary treatments had no significant effect on feed intake, while water intake insignificantly decreased. Digestibility coefficients of dry matter, organic matter, and crude protein significantly (P < 0.05) improved. However, dietary treatment had no significant effect on crude fiber and nitrogen-free extract digestibilities. Values of total digestible nutrient and digestible crude protein significantly (P < 0.05) increased. Nitrogen retention was positive for all groups. Dietary treatments had no significant effect on ruminal pH but insignificantly decreased ammonia nitrogen (NH3–N) concentrations. However, total volatile fatty acid concentration was increased. Dietary treatments increased molar proportion of volatile fatty acids. Final weight, body weight gain, and average daily gain were significantly (P < 0.05) decreased, while feed conversion ratio insignificantly decreased. Inclusion of PPW decreased total daily feeding costs of experimental rations. PPW could be used as a source of energy in lamb rations instead of corn grain. Also, PPW can be successfully fed to lamb without any adverse effect on their performance, and it can be an economical substitute for grain.  相似文献   
990.
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