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501.
Germplasm lines of finger millet (400 lines) with diverse genetic background were screened to identify high CER and CGR genotypes. Considerable variation was noticed in LA, biomass and all the growth and yield attributes but range in stomatal frequency was relatively less. The difference in plant stomatal number was more due to variation in LA but not the frequency. Since high TDM is a primary criteria for achieving higher grain yield, from amongst the high biomass types, genotypes differing in LA/DM ratios but with similar DM and HI were selected. In six genotypes each from low and high LA/DM group which showed stability across the environment, gas exchange characteristics were studied. The CER in low LA/DM types was 45 per cent higher. A significant negative relationship (r = -0.87) exists between CER and LA/DM ratios. Higher net assimilation rate in these genotypes therefore could be attributed mainly due to CER rather than the dark respiration.
An approach to identify high CER types with high CGR and low plant conductances from the germplasm lines has been proposed. These conceptual types will have high CGR but with low functional LA, thus low transpiration leaf surface. These conceptual types will have specific advantage under rainfed water limited conditions.  相似文献   
502.
503.
The inhibition of the growth of Rhizoctohia solani in vitro by carbendazim was maximal at 20°C and at pH 8. In pot tests using mung bean, maximum protection against ‘damping-off’, caused by R. solani, was obtained when seeds were treated with carbendazim. at 1 g a. i. kg?1 (as a wettable powder) and sown in river sands of pH 7 and 8, kept at a 20°C. Better disease control was obtained in soils kept moist by frequent watering than in soils under water stress. Disease control was best in sandy soil and least in clay loam. The implications of these results, for the antifungal efficacy of carbendazim under diverse soil conditions, are discussed.  相似文献   
504.
505.
A two year field study conducted at the Indian Agricultural Research Institute, New Delhi, India showed that for direct seeded rice (drilled in moist bed) blending of urea with nitrification inhibitor N-Serve was the most advantageous; it gave significantly higher grain and straw yield nitrogen uptake by rice than urea super-granules (USG), urea briquettes (UB), sulphur coated urea (SCU), neem cake coated urea (NCU) and prilled urea. USG or UB were next in order and significantly superior to SCU, NCU and prilled urea, which were equally effective. Nitrogen application to rice left a significant residual effect on succeeding wheat, but various sources of nitrogen studied did not differ significantly in this respect.  相似文献   
506.
Infectious diseases have been responsible for large-scale declines in many endangered animals. Disease outbreaks in small populations have probably led to the eventual extinction of such endangered animals in the wild. The endangered Asiatic lion (Panthera leo persica) population may also face such threats. This was evident from this study on captive Asiatic lions from western India, which were sampled from December 1998 to March 1999. Fifty-six Asiatic lions, including 17 hybrid lions (Afro-Asian crosses) from six captive centers in western India, were tested for antibodies against canine distemper virus (CDV), feline parvovirus (FPV), feline immunodeficiency virus (FIV), and feline leukemia viral (FeLV) antigen. Agar gel immunodiffusion test and dot immunobinding assay were employed for CDV and FPV antibody detection. Commercial enzyme-linked immunosorbent assay kits were used for FIV antibody and FeLV antigen detection. Forty-nine of 56 lions (87.5%) were positive for CDV. All 56 (100%) lions were positive for FPV antibodies. There were no detectable levels of FIV antibodies and FeLV antigens. It was observed that CDV and FPV, two viruses known to cause high mortality in captive carnivores, were widely prevalent in these captive Asiatic lions. It is suggested that these seropositive animals will have the potential to pose a risk of infection to other seronegative animals. Hence, it is imperative to carefully consider any movement, translocation, or reintroduction of these animals to new regions. It is also recommended that these animals be required to undergo standard quarantine and disease screening protocols. The lack of exposure to pathogens, such as FIV and FeLV, would also be a risk, and, hence, identification of reservoirs and screening of in-contact animals is highly recommended. Vaccinations must be considered, using killed or other suitable viral vaccines, which have been proved to be safe, effective, and efficacious in endangered felids.  相似文献   
507.
The present investigation was carried out to study the effect of various levels of dissolved oxygen (DO) on reactive oxygen species (ROS) and cryocapacitation‐like changes in bull sperm. Egg yolk–Tris–glycerol (EYTG) extender was split into four subextenders; viz., Extender I (control; no flushing with liquid nitrogen (LN2)), Extender II, Extender III and Extender IV were flushed with LN2 for 40, 16 and 8 min, respectively. The DO levels were standardized to 11.7, 2, 4 and 8 ppm, respectively, in control (Extender I), Extender II, Extender III and Extender IV. Ejaculates with mass motility of ≥ 3+ were divided into group I (diluted with Extender I), group II (diluted with Extender II), group III (diluted with Extender III) and group IV (diluted with Extender IV) up to 80 × 106 sperm/ml. Extended semen samples were packed in French mini straws (0.25 ml), equilibrated and cryopreserved. Semen samples were evaluated at prefreeze and post‐thaw stage for various parameters (DO, progressive motility (PM), viability (VIB), acrosomal integrity (AI), hypo‐osmotic swelling (HOS) test, ROS, cholesterol (C) and phospholipid (P). The percentage of PM, VIB, AI, HOS test, cholesterol (C) and phospholipid (P) levels, and capacitated sperm were significantly (p < 0.05) higher in groups III and IV as compared to groups I and II. However, the acrosome‐reacted sperm (%; pattern AR) were significantly (p < 0.05) decreased in group III as compared to all other groups. Besides the proportion of sperm displaying tyrosine‐phosphorylated pattern, EA (fluorescence at both equatorial and anterior acrosomal regions, i.e. high capacitation level) was significantly (p < 0.05) reduced in group III compared to all other groups. In conclusion, varying DO levels in the extender significantly affect sperm quality, ROS production and capacitation‐like changes in bulls.  相似文献   
508.
The effects of residual sodium carbonate (RSC) in irrigation water on soil sodication and yield and cation composition of palmarosa (Cymbopogon martinii Roxb. Wats) and lemongrass (Cymbopogon flexuosus Steud Wats) were studied in the open bottom reinforced concrete cemented (RCC) cylindrical barrels embedded in the field and filled with sandy loam soils. The results indicated that the increasing RSC in irrigation water significantly increased the pH, electrolyte conductivity (ECe) and SARe of the soil and, hence, considerably decreased the herb and oil yield of both the palmarosa and lemongrass. The reduction in total herb yield was 14.5, 18.3, 28.8 and 32.0% in palmarosa and 38.6, 46.0, 57.7 and 62.6% in the lemongrass over control at 4.0, 8.0, 12.0 and 16.0 meq/l of RSC, respectively. The total oil yield of palmarosa increased by 22.6% with the increase in RSC from 2.0 (control) to 4.0 meq/l and further increase in RSC decreased the oil yield by 13.0, 22.4 and 22.9% over control at 8,12 and 16 meq/l of RSC, respectively. The total oil yield of lemongrass was decreased by 27.0, 39.4, 47.7 and 50.8% over control at 4, 8, 12 and 16 meq/l, respectively. The concentration of Na increased significantly and K and Ca decreased with increase in RSC of irrigation water in vegetative tissues of both species. The lemongrass accumulates significantly greater amount of Na in shoot tissues as compared to palmarosa and it failed to survive at high RSC after 21 months of transplanting. The results suggests that palmarosa is more tolerant to irrigation water sodicity than the lemongrass.  相似文献   
509.
Background: Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganodermo sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed. Results: Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO3 (1.0), and MgSO4 (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained. Conclusions: The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods.  相似文献   
510.
Vitellogenin is a female-specific calcium-binding glycolipophosphoprotein synthesized in the hepatocytes of fishes. Its synthesis can be induced in fishes of either sex by estradiol or by xenoestrogens. To study the in vitro synthesis of vitellogenin, different culture conditions were set up using the hepatocytes of Clarias gariepinus. The present study reports on a non-enzymatic procedure for isolation and culture of hepatocytes from the liver of the catfish Clarias gariepinus, in order to study the effects of estradiol on vitellogenin synthesis in vitro. The procedure employs chelating properties of ethylenediamine tetracetic acid to achieve cell viability in excess of 95%. Equal numbers of isolated cells were incubated in different culture media viz. RPMI F1640, Medium-199, and Williams’ Medium E. At 36 h, cell attachment and monolayer formation is faster in M-199 and Williams’ Medium E than in RPMI. In order to study the effects of estradiol on vitellogenin synthesis, the isolated hepatocytes were seeded in Williams’ Medium E in 24-well cell culture plates. 17 β-estradiol (E2) was introduced in the culture plates at different concentrations and for different time periods. The media were assayed for vitellogenin using competitive ELISA. Vitellogenin appeared in the medium after 48 h of incubation with 10−5 M estradiol whereas after 72 h of incubation 5×10−7 M E2 could elicit the synthesis.  相似文献   
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