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51.
Tropical Animal Health and Production - The current experiment was performed to find the potential effect of inorganic and organic forms of zinc (Zn) on growth, intestinal histomorphology, immune...  相似文献   
52.
ABSTRACT

Root system is an important factor for crop productivity under water- and nutrient-limited environments. A pot study was conducted to evaluate root system response of three Thai rice varieties (Pathumthani 1, RD57, RD41) under three cultivation methods (dry direct seeding [DDS], wet direct seeding [WDS], transplanting [TP]) and three levels of alternate wetting and drying irrigation (–5, –15, –30 kPa). A second pot experiment examined the effect of potassium (K) rates (0, 80, 120, 160 kg ha–1) on root system response of the same varieties under DDS and TP subjected to alternate wetting and drying at –5 kPa. Pathumthani 1 was more tolerant to moisture stress; RD57 and RD41 showed an inconsistent response to moisture-deficit conditions. Rice plant under TP was more sensitive to moisture stress; rice plant performed better under DDS even at the highest soil moisture stress of –30 kPa. K application at the rate of 120 kg ha–1 as basal under DDS was optimum for root system development of Pathumthani 1, while RD57 and RD41 had higher actual root length at the same K rate regardless of cultivation methods. Alternate wetting and drying up to –30 kPa could be safely applied for the three tested varieties. The performance of root system of Pathumthani 1 was better under DDS method of cultivation. K fertilization at 120 kg ha–1 can be recommended as optimum rate under water-saving cultivation techniques for the three tested varieties.  相似文献   
53.

Yacon (Smallanthus sonchifolius (Poepp.) H. Robinson) leaves is traditionally consumed as herbal tea in many countries including Indonesia. This plant’s antidiabetic properties have been extensively researched, but studies on the responsible active compound identification are scarce. Information on the active compounds is critical for the consistency of Yacon herbal tea quality. The aim of this study was to identify α-glucosidase inhibitors in Indonesian Yacon leaves grown in two different locations using FTIR- and LC–MS/MS-based metabolomics in combination with in silico technique. Yacon leaves ethanol (50 and 95%) and water extracts were tested for α-glucosidase inhibitory activity, with the 95% ethanol extract being the most active. Geographical origins were found to have no major impact on the activity. In parallel, chemical profile of Yacon leaves extract was determined using FTIR and LC–MS/MS. Orthogonal Projection to Latent Structure (OPLS) was used to analyze both sets of data. OPLS analysis of FTIR data showed that compounds associated to α-glucosidase inhibitor activity included those with functional groups –OH, stretched CH, carbonyl, and alkene. It was consistent with the result of OPLS analysis of LC–MS/MS data, which revealed that based on their VIP and Y-related coefficient value, nystose, 1-kestose, luteolin-3′-7-di-O-glucoside, and 1,3-O-dicaffeoilquinic acid isomers, strongly linked to Yacon’s α-glucosidase inhibitor activity. In silico study supported these findings, revealing that the four compounds were potent α-glucosidase inhibitors with docking score in the range of ? 100.216 to ? 115.657 kcal/mol, which are similar to acarbose (? 115.774 kcal/mol) as a reference drug.

Graphical abstract
  相似文献   
54.
European Journal of Plant Pathology - Brown eye spot (Cercospora coffeicola) is one of the main diseases of coffee (Coffea arabica L.) and represents a serious phytosanitary problem for the crop....  相似文献   
55.
The present study was designed to evaluate different honey samples obtained from local market for their quality parameters for assessment of their feasibility for foreign export by comparing it with international standards. The study was conducted at PCSIR laboratories complex, Peshawar, during 2006. The tested samples were evaluated for moisture content, Ash percentage, acid content, HMF and reducing sugars percentage. The moisture content of locally produced honey was in the range of 14.5 to 18.23%. The ash content of locally produced honey samples ranged between 0.047-0.35 which is within the standard limits. The acid content of the honey samples ranged between 19.5 and 38.0 meq kg(-1). The HMF contents of locally produced honeys ranged from 5.3 to 23.20 mg kg(-1). The content of reducing sugar of the tested samples ranged between 43.14 and 81.40% for the tested samples of locally produced honey. All of the samples were found to be in acceptable range of international standards for all of the tested parameters except for only one sample with lower reducing sugars. These samples were marked to be according to the international standards and are healthy for human consumption.  相似文献   
56.
This study was conducted to determine the prevalence of bacteria recovered from bloodstream samples by Bactec 9240 at our hospital wards and to evaluate their antibacterial susceptibility patterns. During January 2001 through December 2004, 9407 referred blood samples in Bactec bottles from admitted patients at three main wards, neonates, pediatrics and adults at Nemazee Hospital, affiliated to Shiraz University of Medical Sciences in Shiraz were processed. Positive cultures were purified and identified according to standard methods. Sensitivity of bacteria to different antibiotics was determined by Kirby-Bauer disk diffusion method. Staphylococcus aureus 132(25%), Escherichia coli 64(12.1%) and Pseudomonas aeruginosa 52(9.8%) were the most pathogenic bacteria which were recovered from the blood samples. Pathogenic microorganisms were isolated from blood samples of 305 (57.8%) at pediatrics, from 181 (34.2%) at adults and from 42 (8%) at neonates wards. The highest antibiotics activities against gram positive isolates observed for vancomycin (98.4%), chloramphenicol (86.4%) and ciprofloxacin (77.4%), while in gram negative bacteria imipenem (96.1%), ciprofloxacin (83%) and amikacin (77.9%), were effective antibiotics. Frequency of isolated bacteria at pediatrics compared to adults and neonates wards were approximately two and seven folds high, respectively which indicates special attention should be paid to pediatrics patients both in prevention and treatment aspects. Vancomycin and imipenim are the effective antibiotics and could cover majority of gram positive and negative bacteria. Therefore, combined administrations of these antibiotics seems mandatory for empirical therapy.  相似文献   
57.
ABSTRACT Chitosan (CHN), a deacetylated derivative of chitin, was shown to be efficient in promoting plant defense reactions. CHN oligomers of different molecular weight (MW) and degree of acetylation (DA) triggered an accumulation of phytoalexins, trans- and cis-resveratrol and their derivatives epsilon-viniferin and piceid, in grapevine leaves. Highest phytoalexin production was achieved within 48 h of incubation with CHN at 200 mug/ml with an MW of 1,500 and a DA of 20% (CHN1.5/20), while oligomers with greater MW were less efficient, indicating that a specific MW threshold could be required for phytoalexin response. Treatment of grapevine leaves by highly active CHN1.5/20 also led to marked induction of chitinase and beta-1,3-glucanase activities. CHN1.5/20 applied together with copper sulfate (CuSO(4)) strongly induced phytoalexin accumulation. CuSO(4) alone, especially at low concentrations also elicited a substantial production of phytoalexins in grapevine leaves. Evidence is also provided that CHN1.5/20 significantly reduced the infection of grapevine leaves by Botrytis cinerea and Plasmopara viticola, and in combination with CuSO(4) conferred protection against both pathogens.  相似文献   
58.
黄土塬边坡植被类型对土壤孔隙的影响   总被引:2,自引:0,他引:2  
黄土塬边坡植被建设以固坡为目的,不同植被的土壤孔隙结构有利于增加降水入渗,从而减少坡面产流的水蚀危害。本研究以长武塬黄土塬边坡的侧柏(Platycladus orientalis)林地、沙棘(Hippophae rhamnoides)灌丛、草地和农地4种植被为研究对象,采集0–30 cm的原状土柱,利用CT扫描和图像处理技术,对其土壤孔隙度、孔隙数目、孔隙成圆率和孔隙分形维数进行定量分析,结合土层样品的理化性质,研究影响土壤孔隙结构的主要因素。结果表明,农地、侧柏孔隙的孔径大小分异不大,而草地、沙棘自身根系互动穿插生成的根孔扩展了孔径分布范围,不仅增加了孔隙度和大孔隙数目,也降低了孔隙成圆率。草地、沙棘有利于降水入渗,是固坡的优先选择。土壤有机质、粘粒含量等性质与孔隙参数之间具有极显著(P<0.001)或显著(P<0.05)相关关系,它们的改变对土壤孔隙特征变化和提高蓄水保土能力具有重要影响。  相似文献   
59.
We examined whether mutation of the platelet‐derived growth factor receptor protein tyrosine kinase (PDGFR)‐α and PDGFR‐β genes contributes to their overexpression in canine vascular tumours. Genomic sequences of trans‐ or juxtamembrane regions of PDGFR‐α and PDGFR‐β were analysed with immunohistochemical staining and polymerase chain reaction‐direct sequencing using DNA from paraffin‐embedded neoplastic tissues of 27 hemangiosarcomas (HSAs) and 20 hemangiomas (HAs). Immunohistochemically, 75% of the HA cases were positive for PDGFR‐α and almost most of the HA cases were negative for PDGFR‐β. Of the HSA cases, 55.6% were negative for PDGFR‐α and 63% were strongly positive for PDGFR‐β. Among the HA cases, 1 missense mutation was detected in PDGFR‐α exon 18 and 1 in PDGFR‐β exon 17. Two HSA cases had missense mutations in exon 14 and 1 in exon 17 of PDGFR‐β. Thus, genomic mutation of trans‐ or juxtamembrane regions of PDGFRs was not the main mechanism driving the activation of receptors in HSA and HA.  相似文献   
60.
The effect of dietary selenium on caprine leukocyte migration inhibitory factor (LMIF) production was examined in vitro using lymphocytes from goats fed a diet deficient in selenium. Selenium deficiency was determined by decreased plasma glutathione peroxidase (GSH-Px). The ability of peripheral blood lymphocytes to produce LMIF induced by concanavalin A (Con A) was significantly (P < 0.05) inhibited when cells from selenium-deficient and selenium-adequate goats were compared. In contrast, no significant (P > 0.05) differences were found between lymphocytes from selenium-deficient and selenium-adequate goats for Interleukin-2 (IL-2) production and blastogenesis induced by Con A. These data suggest that selenium deficiency may selectively impair LMIF production and hence the ability of lymphocytes to modulate neutrophil migration.  相似文献   
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