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91.
犬脓肿是临床常见的外科疾病之一,常因疮面较大,易形成溃疡,又往往因护理不好及周围环境而缠绵不愈,且常有日趋严重之象。犬脓肿多因外伤(创伤、划伤、缰绳勒伤)和注射不消毒或不彻底引起。多发于颈部及四肢上部。  相似文献   
92.
兽药的不合理使用可导致动物产品及环境中兽药残留超标,从而对公共卫生安全构成威胁。QuEChERS法是一类快速、简便、经济、高效、耐用和安全的样品前处理方法,常用于植物产品农药检测。通过持续优化,目前该方法开始在动物产品兽药残留检测中得到应用。本文综述了QuEChERS法的特点,探讨了该方法在畜禽产品或样品兽药残留检测中的优化与应用。与植物样品相比,动物相关样品基质复杂,脂肪含量较高,因此需要对QuEChERS法进行优化。常用的优化方式包括提取液优化、脱水盐优化和吸附剂优化。目前QuEChERS法在畜禽肌肉、内脏、鸡蛋、牛奶及相关产品以及尿液、粪便等环境样品兽药残留萃取中得到应用。随着与其他提取净化方法的连用以及自动化提取装置的不断更新,未来QuEChERS法会得到持续优化与发展,其提取效率和净化效果将进一步得到提高,并将在动物产品残留检测中发挥重要作用。  相似文献   
93.
  1. The advantage of supplemental sodium bicarbonate (NaHCO3) on eggshell quality in laying hens changes with age. Besides increasing calcium (Ca) secretion in the eggshell gland, it may improve Ca absorption in the intestine or kidney.

  2. Hy-Line Brown layers (n = 384), 25 weeks of age, were allocated to two treatment groups in two experiments, each of which included 4 replicates of 24 hens. Hens were fed a basal diet (control) or the basal diet containing 3 g NaHCO3 g/kg for 50 or 20 weeks in Experiment 1 or 2, respectively. A 24-h continuous lighting regimen was used to allow hens to consume the dietary supplements during the period of active eggshell formation.

  3. In Experiment 1, particularly from 25 to 50 weeks of age, and in Experiment 2, NaHCO3 supplementation favoured hen-d egg production at the expense of lower egg weight. The increased eggshell thickness should have nothing to do with the additional eggshell formation, because of the unchanged egg mass and daily eggshell calcification.

  4. At 35 weeks of age in both experiments, NaHCO3 supplementation increased duodenal expression of calbindin-d28k (CaBP-D28k) protein, contributing to higher Ca retention and balance.

  5. From 50 to 75 weeks of age in Experiment 1, the hens had little response to NaHCO3 supplementation and showed a negative trend on eggshell thickness and strength.

  6. It is concluded that dietary supplementation with 3 g NaHCO3 g/kg improves Ca absorption and eggshell quality of laying hens during the peak but not late production period, with the introduction of continuous lighting.

  相似文献   
94.
Bactrian camel is an ancient and precious species of livestock; that is, unique resources exist in the desert and have important economic and scientific value. In recent years, the number of Bactrian camels has declined sharply. Due to its long reproductive cycle and seasonal oestrus, the mechanism of oestrus is unknown. To identify candidate biomarkers of reproduction, we performed a comprehensive proteomic analysis of serum from Bactrian camel in oestrus and non-oestrus, using isobaric tags for relative and absolute quantitation (iTRAQ) coupled with tandem mass spectrometry. We identified 359 proteins, of which 32 were differentially expressed: 11 were up-regulated and 21 were down-regulated in samples from camels in oestrus. We validated the differential expression of a subset of these proteins using qPCR and Western blot. Gene ontology annotation identified that the differentially expressed proteins function in cellular processes, metabolic processes and immune system processes. Notably, five of the differentially expressed proteins, PCGF5, histone H1.2, RBP4, FOLR1 and ANTXR2, are involved in reproductive regulatory processes in other animals. KEGG enrichment analysis demonstrated significant enrichment in several cardiac-related pathways, such as ‘dilated cardiomyopathy’, ‘hypertrophic cardiomyopathy’, ‘cardiac muscle contraction’ and ‘adrenergic signalling in cardiomyopathy’. Our results suggest that candidate biomarker (PCGF5, histone H1.2, RBP4, FOLR1 and ANTXR2) discovery can aid in understanding reproduction in Bactrian camels. We conclude that the profiling of serum proteomes, followed by the measurement of selected proteins using more targeted methods, offers a promising approach for studying mechanisms of oestrus.  相似文献   
95.
近年来,羊多杀性巴氏杆菌病在内蒙古自治区呼伦贝尔市时有发生。为了解呼伦贝尔市羊源多杀性巴氏杆菌荚膜血清型流行状况,通过建立多杀性巴氏杆菌分子生物学诊断方法,以羊病变组织为研究对象,对呼伦贝尔市羊源多杀性巴氏杆菌,进行荚膜血清群分子流行病学调查,同时应用K-B纸片琼脂扩散法,对分离菌株进行药物敏感性试验,以找到针对本地区流行株的敏感药物。结果显示:从采集的35份病羊肺组织病料中,分离出12株B群、9株D群多杀性巴氏杆菌,未分离出其他血清群;分离菌株对青霉素、链霉素耐药率最高,对氯霉素、四环素、诺氟沙星、环丙沙星敏感。结果表明,呼伦贝尔市流行的羊源多杀性巴氏杆菌以B群、D群为主,且分离菌株对青霉素、链霉素产生了较高的耐药性,需指导和监管抗菌药物的合理使用。本研究查清了本地区流行的优势多杀性巴氏杆菌血清群,找到了针对性敏感药物,这为该市羊巴氏杆菌病防控提供了有效的技术支撑,也对多杀性巴氏杆菌病流行病学监测和基因多样性研究奠定了基础。  相似文献   
96.
为了了解和掌握我市猪场的猪瘟免疫情况及感染高致病性禽流感疫病的可能性,我所分别于2005年2月和4月两次对全市范围内各类型的养猪场免疫猪瘟的猪只采集血清941份,进行猪瘟血清抗体监测和猪高致病性禽流感疫情血清学监测。现将监测结果报告如下。  相似文献   
97.
用食盐作为助溶剂采用细胞自溶法,对解脂假丝酵母33M candida lipolytica细胞壁进行破碎后提取神经酰胺,用SPE(固相萃取法)将神经酰胺与膜中其它脂类分离,分别应用TLC(薄层色谱)方法和HPLC-ELSD(高效液相色谱-蒸发光散射器)对其进行定性和定量分析,取得了良好效果。  相似文献   
98.
根据雏鸡血清酶活性对蛋鸡进行早期选种的研究   总被引:6,自引:1,他引:6  
本研究测定了147只8、12周龄S220母雏血清碱性磷酸酶(AKP)、谷草转氨酶和乳酸脱氢酶活性,估测其遗传力及其与产蛋性能间的表型相关和遗传相关。结果表明,8周龄血清AKP活性遗传力为0.62,300日龄产蛋量遗传力为0.20,两者间的遗传相关为0.8245。利用8周龄血清AKP活性作为辅助性状对300日龄产蛋量进行间接选择,其间接选择效率为个体选择的1.4519倍,为家系选择的1.4837倍,为合并选择的1.1887倍。因此,8周龄血清AKP活性可作为蛋鸡早期选种血液生化指标之一。  相似文献   
99.
BackgroundInterferon lambda receptor 1 (IFNLR1) is a type II cytokine receptor that clings to interleukins IL-28A, IL29B, and IL-29 referred to as type III IFNs (IFN-λs). IFN-λs act through the JAK-STAT signaling pathway to exert antiviral effects related to preventing and curing an infection. Although the immune function of IFN-λs in virus invasion has been described, the molecular mechanism of IFNLR1 in that process is unclear.ObjectivesThe purpose of this study was to elucidate the role of IFNLR1 in the pathogenesis and treatment of porcine reproductive and respiratory syndrome virus (PRRSV).MethodsThe effects of IFNLR1 on the proliferation of porcine alveolar macrophages (PAMs) during PRRSV infection were investigated using interference and overexpression methods.ResultsIn this study, the expressions of the IFNLR1 gene in the liver, large intestine, small intestine, kidney, and lung tissues of Dapulian pigs were significantly higher than those in Landrace pigs. It was determined that porcine IFNLR1 overexpression suppresses PRRSV replication. The qRT-PCR results revealed that overexpression of IFNLR1 upregulated antiviral and IFN-stimulated genes. IFNLR1 overexpression inhibits the proliferation of PAMs and upregulation of p-STAT1. By contrast, knockdown of IFNLR1 expression promotes PAMs proliferation. The G0/G1 phase proportion in IFNLR1-overexpressing cells increased, and the opposite change was observed in IFNLR1-underexpressing cells. After inhibition of the JAK/STAT signaling pathway, the G2/M phase proportion in the IFNLR1-overexpressing cells showed a significant increasing trend. In conclusion, overexpression of IFNLR1 induces activation of the JAK/STAT pathway, thereby inhibiting the proliferation of PAMs infected with PRRSV.ConclusionExpression of the IFNLR1 gene has an important regulatory role in PRRSV-infected PAMs, indicating it has potential as a molecular target in developing a new strategy for the treatment of PRRSV.  相似文献   
100.
Stearoyl-CoA desaturase 1 (SCD1) catalyses the synthesis of conjugated linoleic acid (CLA) and mono-unsaturated fatty acids (MUFA) in the mammary gland of ruminant animals. Considerable variations in CLA and MUFA have been reported among animals of the same contemporary group. We hypothesized that single nucleotide polymorphisms (SNPs) in the 5' and 3' untranslated regions (UTRs) of the SCD1 gene would influence the production of SCD1 enzyme and consequently its activity in the mammary gland, which may account for some of the observed within breed variations in CLA and MUFA. The 5' and 3'UTRs of the SCD1 gene of 46 Holsteins and 35 Jerseys were analysed for SNPs by sequencing. No SNPs were identified in the 5'UTR, while 14 SNPs were identified in the 3'UTR region. Further analysis revealed three haplotype structures or regulatory variants in Holsteins: named H1, H2 and H3 and only H1 and H3 in Jerseys. An IRES motif was found in the H1 variant. A subsequent association study involving the milk fatty acid profiles of 862 Holstein cows found the H1 regulatory variant to be associated with higher C10 and C12 desaturase indices and consequently with higher contents of C10:1 and C12:1 relative to the H3 variant. The effects of the H2 variant were intermediate to those of H1 and H3. SNPs in the 3'UTR of the SCD1 gene could therefore explain some of the within-breed variations in MUFA content of milk fat.  相似文献   
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