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1.
Plasma N-terminal pro-atrial natriuretic peptide (NT-proANP) concentration increases with progression of myxomatous mitral valve disease (MMVD) in dogs. This multicentre, prospective study compared plasma NT-proANP, N-terminal pro-brain natriuretic peptide (NT-proBNP), ANP, and cardiac troponin I (cTnI) concentrations in dogs with MMVD for their characteristics and discriminatory ability to detect cardiac dilatation and congestive heart failure (CHF). Thirty-six healthy dogs and 69 dogs with MMVD were included. Clinical variables were obtained via physical examination, thoracic radiography, and echocardiography. The discriminatory ability of each cardiac biomarker (CB) to determine the presence or absence of cardiac dilatation (event 1) and CHF (event 2) was evaluated using the receiver operating characteristic curves. Plasma NT-proANP, NT-proBNP, and ANP concentrations showed a significant association with the left atrium/aorta ratio (P<0.01). The area under the curve of plasma NT-proANP and NT-proBNP concentrations were 0.72 and 0.75, respectively in event1 and 0.72 and 0.76, respectively in event2. Plasma NT-proANP and NT-proBNP concentrations showed sensitivity 80.0 and 80.0%; specificity 67.6 and 64.7% in event1 (cutoff value; 8,497.81 pg/ml and 1,453.00 pmol/l, respectively) and sensitivity 85.7 and 81.0%; specificity 60.4 and 64.6% in event2 (cutoff value; 8,684.33 pg/ml and 1,772.00 pmol/l, respectively). In dogs with MMVD, plasma NT-proANP, NT-proBNP, and ANP concentrations increase with left atrial enlargement. Particularly, plasma NT-proANP and NT-proBNP concentrations appeared to be equally useful in the discriminatory ability to detect cardiac dilatation and CHF.  相似文献   
2.
研究了以索尔邦百合(Lilium Sorbonne)的鳞片叶为外植体的组培和植株离体再生技术,培养基采用MS基本培养基,附加不同的激素组合.分别获得诱导的愈伤组织、芽及根,并遴选出最佳激素组合,以确立索尔邦百合组织培养再生系统.试验结果表明适合的诱导培养基是MS BA0.5mg/L NAA 0.2mg/L;继代培养基为MS 2,4-D 1.0mg/L和MS BA 0.5mg/L NAA0.2mg/L;生根培养基是1/2MS IBA0.2mg/L和1/2MS NAA0.2mg/L.该方法最大增殖倍数达到5.74.  相似文献   
3.
1. The aim of this study was to examine the effects of dietary fibre sources on growth and on the development of the gastro-intestinal tract in growing geese. 2. Six-week-old female White Roman geese were divided at random into 6 groups with 6 dietary treatments. Diets were isoenergetic and isonitrogenous and contained alfalfa meal, barley bran, rice hulls, cellulose, pectin or lignin as the major dietary source of fibre. 3. Food intake was significantly higher in the barley bran group than in the other groups. Both daily weight gain and food conversion of the pectin and alfalfa meal groups were lower than those of the other groups. 4. In the 9-week-old geese, the relative weight and the length of the small intestine did not significantly differ among treatment groups. However, the relative weight was significantly lightest and the caecal length was significantly shortest ( P 0.05) in the pectin group. 5. Activities of amylase and cellulose hydrolases of the caecal contents were also highest in the pectin group. 6. From SEM micrographs, no morphological damage of the villi was observable in the different intestinal segments of the geese in any of the treatments.  相似文献   
4.
Orf virus (ORFV), a member of parapoxvirus, is an enveloped virus with genome of double-stranded DNA. ORFV causes contagious pustular dermatitis or contagious ecthyma in sheep and goats worldwide. In general, detection of viral DNA and observing ORFV virion in tissues of afflicted animals are two methods commonly used for diagnosis of orf infection; however, isolation of the ORFV in cell culture using virus-containing tissue as inoculum is known to be difficult. In this work, the ORFV (Hoping strain) isolated in central Taiwan was successfully grown in cell culture. We further examined the biochemical characteristic of our isolate, including viral genotyping, viral mRNA and protein expression. By electron microscopy, one unique form of viral particle from ORFV infected cellular lysate was demonstrated in the negative-stained field. Moreover, immunomodulating and anti-influenza virus properties of this ORFV were investigated. ORFV stimulated human monocytes (THP-1) secreting proinflammatory cytokines IL-8 and TNF-α. And, pre-treatment of ORFV-infected cell medium prevents A549 cells from subsequent type A influenza virus (IAV) infection. Similarly, mice infected with ORFV via both intramuscular and subcutaneous routes at two days prior to IAV infection significantly decreased the replication of IAV. In summary, the results of a current study indicated our Hoping strain harbors the immune modulator property; with such a bio-adjuvanticity, we further proved that pre-exposure of ORFV protects animals from subsequent IAV infection.  相似文献   
5.
騰格里沙漠地区沙地土壤微生物学特性的研究   总被引:3,自引:0,他引:3  
張憲武  許光輝 《土壤学报》1962,10(3):227-234
沙漠的严重危害主要是流沙的移动。因此,沙漠改造和治理中的重要工作之一。是采取各种措施固定流沙[1]。一般說来,固定流沙有两种方法:一种是植物固沙,一种是机械固沙。机械固沙是暂时的固沙法,为固定流沙不可缺少的一环;而植物固沙是一种最根本最可靠的永久固沙方法[2,3]流沙一经生长植物,它的基本性质就要改变,形成固定沙丘。这就为进一步改造利用沙漠,创造了先决条件。时的固沙法,为固定流沙不可缺少的一环;而植物固沙是一种最根本最可靠的永久固沙方法[2,3]流沙一经生长植物,它的基本性质就要改变,形成固定沙丘。这就为进一步改造利用沙漠,创造了先决条件。  相似文献   
6.
The effects of jingsongling (JSL) and xylazine on heart rate (HR) and mean arterial pressure (MAP) were studied in five conscious male dogs. An i.v. injection of xylazine (1 mg/kg) caused a bradycardia, an initial hypertension, and a subsequent hypotension. An i.v. injection of JSL (1 mg/kg) caused a bradycardia and a 20-min hypertension without a subsequent hypotension. Atropine sulfate (45 micrograms/kg, i.v.) increased HR for 30 min without changing MAP, and antagonized JSL-induced bradycardia for at least 60 min. There was a subsequent rebound bradycardia. Atropine sulfate potentiated JSL-induced hypertension in both magnitude and duration. Yohimbine (0.1 mg/kg, i.v.), an alpha 2-adrenoceptor antagonist, increased HR and MAP for 110 and 70 min, respectively. Yohimbine not only failed to potentiate but even reversed the pressor effect of JSL in a dose-dependent manner. Yohimbine also caused a dose-dependent reversal of JSL-induced bradycardia. Tolazoline (5 mg/kg, i.v.), a nonselective alpha-adrenoceptor antagonist, increased MAP for 20 min without changing HR. Tolazoline also reversed JSL-induced hypertension and bradycardia. Prazosin (1 mg/kg), an alpha 1-adrenoceptor antagonist, decreased MAP and increased HR for at least 110 min. Prazosin reversed JSL-induced hypertension but failed to affect JSL-induced bradycardia. These results indicated that: (1) JSL-induced bradycardia and hypertension are mediated by alpha 2-adrenoceptors; (2) yohimbine and tolazoline may be useful in antagonizing these untoward reactions associated with JSL administration, whereas prazosin and atropine were not found to be beneficial in this regard.  相似文献   
7.
 比較大規模的传病試驗的結果証知小米红叶病病毒不借种子传播,很难或者不能用机械式方法传染。  相似文献   
8.
 过去,国內外許多学者証明,适当的应用微量元素和生长刺激剂处理种籽,对农作物苗期生长有促进作用,也常常收到提高产量的效果。关于应用于棉籽处理方面,波波甫应用了溴化鉀浸种,显著的提高了棉花的产量。  相似文献   
9.
多伦县沙地云杉混交林物种多样性研究   总被引:1,自引:0,他引:1  
以多伦县沙地云杉林3条样带的群落调查数据为基础,研究了沙地云杉混交林的物种组成结构,分析了3个典型群落乔木层、灌木层、草本层的物种多样性。结果表明:沙地云杉混交林植物种类丰富,乔木层、灌木层、草本层共有植物71种,群落垂直结构分层明显;多伦县沙地云杉与白桦混交林物种多样性较丰富,在群落梯度上,群落Ⅰ为52种,群落Ⅱ为45种,群落Ⅲ为47种,物种丰富度指数大小顺序为群落Ⅰ>群落Ⅲ>群落Ⅱ;群落的物种多样性指数变化规律大致相同,均为草本层>灌木层>乔木层;3个典型群落的物种均匀度指数变化规律基本一致,为乔木层最大,灌木层其次,草本层最小。通过对多伦县沙地云杉混交林物种多样性的研究,为加强沙地云杉生物多样性的保护和经营管理提供理论依据。  相似文献   
10.
Feitsui reservoir, the major water supply of Taipei city, has shown declining water quality in recent years. The reservoir is located in an area famous for tea cultivation, and the question arises as to whether the hillside tea plantations have contributed to increased sediment and nutrient discharge into the reservoir. In this study, soil and phosphorus redistribution were examined along a steep tea plantation in the reservoir's catchment and the provenance of reservoir sediment was assessed. Fallout radionuclides were used as soil erosion/deposition tracers and as markers of sediment sources. Continuous fertilizer application has raised (inorganic) phosphorus levels in the studied tea plantation. The plantation's narrow bench terraces trap eroded material and slow down soil and nutrient translocation. Nevertheless, eroded soil and phosphorus have accumulated on a vegetated toeslope below the tea plantation. The reservoir sediment contained significant amounts of inorganic phosphorus and cesium-137, and application of a mixing model resulted in a surface soil contribution of approximately 30%. This points towards tea plantations as possible sediment and pollutant sources and underlines the necessity of soil conservation strategies, such as the maintenance of vegetated riparian buffer zones. However, other sources, such as landslide debris and urban wastewaters, cannot be entirely ruled out. Further research is needed to better characterize the catchment's soils and sediments and to improve sediment fingerprinting efforts. Potential point and non-point pollution sources need to be examined in detail to better understand how phosphorus enters the reservoir.  相似文献   
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