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Journal of Plant Diseases and Protection - In precision agriculture, pesticides and other inputs shall be used precisely when (and where) they are needed. European Directive 2009/128/EC calls for...  相似文献   
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Active surveillance of bats in France started in 2004 with an analysis of 18 of the 45 bat species reported in Europe. Rabies antibodies were detected in six indigenous species, mainly in Eptesicus serotinus and Myotis myotis, suggesting previous contact with the EBLV-1 rabies virus. Nineteen of the 177 tested bats were shown serologically positive in seven sites, particularly in central and south-western France. Neither infectious viral particles nor viral genomes were detected in 173 and 308 tested oral swabs, respectively. The presence of neutralising antibodies in female bats (18.6%) was significantly higher than in males (5.6%).  相似文献   
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OBJECTIVE: To compare the attitudes of French veterinarians to pain, and their provision of analgesia to animals, with that reported from other countries. STUDY DESIGN: Epidemiological study. METHODS: In June 1999, 379 French veterinarians were surveyed to ascertain their views on pain evaluation and control in dogs and cats, and their use of analgesics in daily practice. Survey results are expressed as a percentage of responses. RESULTS: The questionnaire was returned by 189 veterinarians (49.9%). The response rate was influenced by age (younger veterinarians were more likely to respond) but not gender. A majority (99.5%) expressed moderate to extreme concern over pain in their patients. Pain evaluation was based on the animal's attitude (88.3% dogs, 82.5% cats), interaction with the caregiver, response to palpation of the painful area (66.5% dogs, 62.7% cats) and inappetence (29.3% dogs, 46.3% cats, p < 0.001). Only 14.3% of respondents considered their knowledge of pain recognition to be inadequate. Many (58.8%) considered their methods of pain quantification and control (47% dogs, 59% cats) to be inadequate. Difficulties in recognizing pain (58.3%), a lack of knowledge in the appropriate use of analgesics (41.7%) and fear of drug side effects (30%) were used to explain inadequate provision of analgesia. Only 16.1 and 8.1% used opioids in dogs and cats, respectively. This low level of use resulted from the imposition of French narcotic legislation (79.9%) and lack of knowledge of opioid pharmacology (73.7%). Nonsteroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids were the most commonly used analgesics in both species (100% (dogs) and 96.7% (cats)). The most popular NSAID used in France was tolfenamic acid, followed by meloxicam (dogs), ketoprofen, nimesulide (cats) and carprofen (dogs). The type of surgery performed influenced the use of analgesics, from 17.2% for castration to 83.7% for orthopaedic procedures. Nonsurgical conditions believed to warrant analgesia included osteoarthritis (97.8%), trauma (97.3%) and bone neoplasia (93.4%). Female veterinarians were more likely than males to evaluate pain and provide analgesia. CONCLUSION: French practitioners demonstrate a level of interest in analgesia, which appears to be at least equivalent to that reported from English-speaking countries. The signs used to indicate the presence of pain do not, in general, appear to differ. Excessive confidence in their ability to recognize pain (despite a general ignorance of the subject), the minor role of animal health technicians in pain management and misconceptions about analgesics (mainly opioids) are French pecularities.  相似文献   
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形成足囊是海蜇(Rhopilema esculenta Kishinouye)螅状幼体无性生殖的方式。但已形成的足囊,有的可萌发为新的螅状幼体,有的则不萌发乃致死亡。为探讨足囊的萌发机制,了解海蜇在自然条件下的种群数量变动规律,作者首先就温度、盐度和光度等环境因子对足囊萌发的影响进行观察,温度实验在0°—30℃范围内分7组,实验结果表明:10℃以下(包括℃)足囊不萌发;15℃—30℃范围内,足囊萌发率随温度升高而增加,25℃和30℃时足囊萌发率最大,为23.33%(实验进行22天)。盐度实验是在20°±1℃温度下,在盐度2~32.1‰范围内分16个梯度,每梯度又分别设黑暗与自然光两种光度水平,实验结果表明,盐度在8‰以下(包括8‰)足囊死亡,足囊萌发的最适范围为18~22‰,在盐度为22‰黑暗条件下,足囊萌发率最高为43.33%(实验进行24天),黑暗有利于足囊萌发。  相似文献   
47.
微藻高密度培养中的生长指标和适应机制   总被引:3,自引:0,他引:3  
以雨生红球藻为材料,利用5cm光径平板式光生物反应器,在室内人工光照、通气条件下,建立高密度培养体系,探讨了微藻高密度培养中的生长指标问题。结果发现,表述微藻生长的传统指标出现失真现象。如在高密度培养生物量增加时,叶绿素含量或细胞数目指标都在一定程度上与干重指标反映的生长信息相背离,甚至出现相反的变化趋势。这主要是由于随着密度增高,细胞间的互相遮蔽作用加剧,单个藻细胞所能获得的光能逐渐减少。细胞在适应光能减弱的过程中,无论藻细胞体积大小还是单个藻细胞叶绿素含量都发生了明显变化。因此,建议评估高密度体系中微藻细胞的生长状况时,应当充分地考虑高密度效应对藻细胞生物学特性的影响,从对多种生长指标的综合分析中获得正确、客观的生长信息。同时,作者还发现微藻细胞群体和个体之间存在两种完全不同的高密度适应机制,协同适应机制和争夺机制。  相似文献   
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Hepatitis E virus (HEV) can cause enterically-transmitted hepatitis in humans. The zoonotic nature of Hepatitis E infections has been established in industrialized areas and domestic pigs are considered as the main reservoir. The dynamics of transmission in pig herds therefore needs to be understood to reduce the prevalence of viremic pigs at slaughter and prevent contaminated pig products from entering the food chain. An experimental trial was carried out to study the main characteristics of HEV transmission between orally inoculated pigs and naïve animals. A mathematical model was used to investigate three transmission routes, namely direct contact between pigs and two environmental components to represent within-and between-group oro-fecal transmission. A large inter-individual variability was observed in response to infection with an average latent period lasting 6.9 days (5.8; 7.9) in inoculated animals and an average infectious period of 9.7 days (8.2; 11.2). Our results show that direct transmission alone, with a partial reproduction number of 1.41 (0.21; 3.02), can be considered as a factor of persistence of infection within a population. However, the quantity of virus present in the environment was found to play an essential role in the transmission process strongly influencing the probability of infection with a within pen transmission rate estimated to 2 ⋅ 10− 6g ge− 1d− 1(1 ⋅ 10− 7; 7 ⋅ 10− 6). Between-pen environmental transmission occurred to a lesser extent (transmission rate: 7 ⋅ 10− 8g ge− 1d− 1(5 ⋅ 10− 9; 3 ⋅ 10− 7) but could further generate a within-group process. The combination of these transmission routes could explain the persistence and high prevalence of HEV in pig populations.  相似文献   
49.
东南太平洋公海智利竹筴鱼年龄与生长研究   总被引:2,自引:1,他引:1  
智利竹筴鱼是一种重要的中上层经济鱼类,对其生活史关键过程的认识还相当有限。根据2006年5-8月在智利公海采集的智利竹筴鱼样本,利用其中963尾智利竹筴鱼耳石对其年龄进行了鉴定,估算了智利竹筴鱼叉长体重关系以及von Bertalanffy生长方程参数,并分析了智利竹筴鱼耳石重量(OW)与年龄的关系。研究结果表明,样本最大年龄9龄,最小年龄2龄,样本年龄组成以4龄为主(71.5%)。智利竹筴鱼叉长体重方程参数a、b分别为0.000 03和2.801 9,von Bertalanffy生长方程参数L∞为738.4 mm,k为0.107,t0为-1.08。耳石重量与年龄呈显著线性关系(r=0.74,P<0.001),表明耳石重量可用于智利竹筴鱼年龄鉴定。  相似文献   
50.
通过采集星斑川鲽(Platichthys stellatus)血浆和血清样品,检测并比较其7项生化指标的异同。结果显示:谷草转氨酶(AST)、谷丙转氨酶(ALT)、碱性磷酸酶(ALP)、甘油三脂(TG)及总蛋白(TP)含量无显著性差异(P>0.05),而二者总胆固醇(T-CHO)和血糖(GLU)含量差异显著(P<0.05)。相关性分析结果表明,7项生化指标检测血清与血浆间存在高度相关性(0.9380.05),表明星斑川鲽部分血液指标受个体大小的影响,因此在对星斑川鲽的血液学诊断及营养水平对其血液学指标影响的考察中,应充分考虑鱼体大小的影响。  相似文献   
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