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411.
Sorghum is one of the most drought-tolerant grain crops and is used in biofuel production. Since sorghum is often exposed to drought and high temperature (heat) stress, this study investigated the effect of stress applied at different phenological stages of crop development on the glucose levels in grain and subsequent ethanol production. Short season sorghum hybrid DK-28E grown under controlled environment was exposed to drought and heat stress at five different stages of growth, namely: (1) pre-flowering (boot leaf emergence) to flowering, (2) flower to seed-set, (3) seed-set to early seed-fill, (4) early seed-fill to mid seed-fill, and (5) mid seed-fill to late seed-fill stage. Drought stress at any of the growth stages did not statistically affect either the glucose content or the ethanol production compared to the control (337 mg/g), although the ethanol yield increased up to 4.5% (352 mg/g) in flowering to seed-set stage. Heat stress, on the other hand, significantly reduced the glucose release and ethanol yield compared to the control (322 mg/g). Marginal ethanol yield reduction by 9% (293 mg/g) and 8.3% (295 mg/g) was seen in plants stressed during early seed-fill to mid seed-fill and mid seed-fill to late seed-fill stages, respectively. The results suggest that the phenological stage when sorghum is exposed to stress affects the ethanol yield. Overall, from the point of ethanol yield, it appears that grain sorghum cultivated in semi-arid regions where heat and drought stress are prevalent can be used for biofuel production. However, economic viability of ethanol production, especially of grain sorghum from high temperature stress needs to be investigated.  相似文献   
412.
We conducted a tuberculosis (TB) serosurveillance program of captive elephants in Nepal and compared hematology and biochemistry parameters between seropositive and seronegative elephants. A total of 153 elephants (male=20, female=133) from four national parks were tested for TB using the ElephantTB STAT-PAK® Assay (ChemBio Diagnostic Systems, Inc., Medford, NY, USA). The mean reported age for 138 elephants was 38.5 years (range 2–71 years). Seroprevalence for TB was 21.56% (33/153). The majority of seropositive elephants were female (n=30) and from Chitwan National Park (n=29). The occurrence of TB seropositive cases in other more remote national parks suggests TB may be widespread among the captive elephant population of Nepal. Hematology and biochemistry analyses were performed on 13 and 22 seropositive elephants, respectively and, nine elephants from a seronegative TB herd for comparison. Hematology parameters (hemoglobin, packed cell volume, platelet, white blood cells, and erythrocyte sedimentation rate) were comparable between the two groups. Total protein, globulin, and lactate dehydrogenase were significantly higher in seronegative elephants, and bilirubin was significantly higher in seropositive elephants whereas blood urea nitrogen, creatinine, glutamic oxaloacetic transaminase/aspartate aminotransferase (GOT/AST), glutamic pyruvic transaminase/alanine aminotransferase (GPT/ALT), gamma glutamyl transferase (GT), and albumin were not significantly different. The range of biochemical parameters that were significantly different between seropositive and seronegative elephants had narrow ranges. Thus, the potential of these parameters as a direct biomarker for TB diagnosis is limited based on the findings in this study. We recommend including blood parameters in future TB surveillance studies.  相似文献   
413.
Parthenium or famine weed (Parthenium hysterophorus L.) is an annual plant originating from the Americas, which is a major invasive alien plant in almost all continents. While the deleterious impacts of the species on agriculture, human and animal health have been well documented, information on the pathways of entry of the species is only occasionally mentioned in the literature. As this invasive alien plant is only recorded as established in Israel and Egypt within the Euro‐Mediterranean region, the European and Mediterranean Plant Protection Organization identified P. hysterophorus as an emerging threat. EPPO therefore performed a Pest Risk Analysis on this species to assess the risk it represents and to consider appropriate management options. The EPPO Pest Risk Analysis main outputs are summarized in this article, indicating the probability of entry of the species via the different pathways within the EPPO region, its probabilities of establishment and spread, and the magnitude of its potential agricultural, environmental and social impacts.  相似文献   
414.
This study examined the effects of water hardness and salinity on yolk sac larvae and swim‐up fry survival of Nile tilapia, Oreochromis niloticus (Chitralada strain), eggs during artificial incubation. Four experiments were conducted to evaluate the effects of hardness, salinity and the sources of saline incubation water. High water hardness treatments (500–4200 mg L?1 as CaCO3) resulted in higher yolk sac larvae and swim‐up fry survival than low water hardness treatments (50.0 and 132 mg L?1 as CaCO3); although yolk sac larvae and swim‐up fry survival did not differ among the high or low hardness treatments. Salinity of 4.0 g L?1 using seawater, and 4.0 and 8.0 g L?1 using unprocessed common salt resulted in the higher survival rate of yolk sac larvae and swim‐up fry than other salinity treatments. Yolk sac larvae and swim‐up fry survival was found to decrease with the increase in salinity and increase with the increase in water hardness. The present study demonstrated the positive effects of increased water hardness level (>132 mg L?1) on yolk sac larvae and swim‐up fry survival. The study also showed that seawater salinity of 4 g L?1 was the most appropriate salinity level for incubating Nile tilapia eggs.  相似文献   
415.
Rice leaffolder, Cnaphalocrocis medinalis, is one of the major foliage feeders found in the rice growing regions in India. When the crop was at maturity, numerous adults of rice leaffolder were found in the rice fields though the larval population gradually decreased, and no eggs were found on rice leaves. The population characteristics of C. medinalis were assessed based on the physiological age status of adults at different crop growth stages. Based on egg development within ovarioles, ovariole appearance, number and colour of fat bodies, and characteristics of bursa copulatrix, physiological age status of the adults was described, which served as a basis for the determination of age composition. C. medinalis adults were found during the first week of August on rice plants, of which 44% were in Age 0 with immature ovaries, indicating immigrants. However, 28% adults each were at Ages 1–2 with developing ovaries, indicating local breeding population. The carryover and off-season survival of C. medinalis were also studied to determine the contribution of the alternative hosts in the population growth that helped in devising efficient management strategies. Rice was the most preferred host followed by Triticum aestivum, Echinochloa crusgulli and Brachiaria plantaginea. Various routes of the carryover of C. medinalis from season to season were discussed.  相似文献   
416.
417.
N-myristoyltransferase (NMT) attaches a 14 carbon fatty acid, myristic acid, to the N-terminal glycine residue of proteins. NMT exists in two isoforms NMT1 and NMT2. Myristoylated proteins play critical roles in protein–protein interactions, cell signaling and oncogenesis. Although elevated expression of NMT1 has been described in colorectal carcinoma, its expression and roles in normal and inflamed lungs of the cattle are unknown. Therefore, we investigated the expression and activity of NMT in a bovine model of lung inflammation induced with Mannheimia hemolytica and in vitro in neutrophils and macrophages. Western blots revealed increased expression of NMT1 in lungs from infected animals compared to control animals. Total NMT activity was reduced in inflamed lungs compared to control animals (p < 0.05) along with increased expression of enolase, a putative inhibitor of NMT. NMT1 staining was observed in the septum, vascular endothelium and the epithelium in the lungs from control as well as infected calves. NMT1 expression was intense in neutrophils in the necrotic areas in the inflamed lungs. Immuno-electron microscopy localized NMT1 in cytoplasm and nuclei of endothelium, pulmonary intravascular macrophages and airway epithelium. Total NMT activity and NMT1 expression were increased in neutrophils and macrophages exposed to Escherichia coli LPS in vitro. NMT knockdown increased apoptosis in activated neutrophils. This is the first report demonstrating expression of NMT in normal and inflamed lungs and a novel role for NMT in regulation of neutrophil lifespan.  相似文献   
418.
Forest fires are one of the major environmen-tal issues globally.In Nepal,substantial amounts of forest biomass and carbon are lost due to fire.Nepal's high val...  相似文献   
419.
A field experiment conducted at the Indian Agricultural Research Institute, New Delhi, India showed that oats (Avena sativa L.) responded (grain yield increase) to zinc (Zn) fertilizer and coating of oat seeds with Zn sulfate or Zn oxide is the best practice. Zinc fertilizer applied to soil, deep placement (5 cm below the seed placement) was superior for growth and yield than soil surface (broadcast) application. Delaying Zn application to 25 days after sowing (first irrigation) was inferior to Zn application at sowing. Partial factor productivity (PFP) of applied Zn varied from 700–2,024 kg grain kg Zn?1, agronomic efficiency (AE) varied from 62–428 kg grain increase kg?1 Zn (applied) and physiological efficiency (PE) of Zn varied from 1,822–3,221 kg grain kg?1 Zn (absorbed). The crop recovery efficiency (CRE) varied from 3.1–17.7%. Thus, adequate Zn fertilizer of oats can lead to higher grain yield and higher Zn concentration in grain (improved quality for human nutrition) under Zn deficient soil.  相似文献   
420.
Alternaria leaf spot (ALS) caused by Alternaria carthami Chowdhury can cause yield loss up to 90% in safflower (Carthamus tinctorius L.) under severe conditions. Even though a definite source of ALS resistance is not available in cultivated species, a few of the wild species, viz. C. palaestinus and C. lantaus, are known to be tolerant to ALS. Therefore, an attempt was made to introgress Alternaria resistance from these species into cultivated species. F1-F8 generations of crosses (PI537632 × C. palaestinus), (C. palaestinus × PI537632), (“Nira” × C. palaestinus) and ([MS 6(O) × C. lanatus] × C. palaestinus) were screened against ALS. ALS infection (%) was recorded in field and quantified using Windias Leaf Image Analysis system. Detached leaf technique was used in laboratory to confirm resistance in interspecific selections. Six resistant and 29 moderately resistant interspecific lines resembling mostly cultivated species were developed. Inheritance of ALS resistance indicated involvement of multiple minor alleles having small effects on resistance. The identified resistant lines could provide potential source of resistance to ALS for safflower breeding programmes.  相似文献   
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