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11.
An extended disease recording programme in pigs has been carried out by the meat inspection service at Sentralslakteriet, Forus, Stavanger. A data system including 57 disease codes has been applied. In the period 1975–1977 an average of 85,000 baconers were slaughtered yearly. About 39 % of these were given disease remarks; 42–47 % of the lesions were directly related to the parasites Sarcoptes scabiei (rind lesions) and Ascaris suum (white spots in the livers). The thoracic cavity was the most commonly affected part of the body with 30–35 % of all recorded lesions.Sixteen disease codes occurred at frequencies above 0.3 %, and they encompassed approx. 97 % of all recorded lesions. Scabies occurred at an average of 12 % of the fatteners. Parasitic hepatitis of severe and moderate degrees were seen in about 11 %, pleurisy in 7 %, pneumonia — severe and moderate — in 5.4 %, pericarditis in 4.3 %, pyaemia and abscess/-es in 2.5 %, tail lesions in 2.3 %, perihepatitis and other non-parasitic liver lesions in 2.2 %, polyarthritis and arthritis in 1.7 %, tuberculous lesions in the cervical lymph nodes in 0.9 %, peritonitis in 0.9 % and atrophic rhinitis — external lesions — in 0.8 % of the carcasses. The majority of the other 41 disease codes occurred at frequencies below 0.1 %.A seasonal variation was pronounced in scabies, numerous white spots in the liver, and tuberculous lesions in the cervical lymph nodes. It could be noted in pleurisy, pericarditis, perihepatitis and other non-parasitic liver lesions, arthritis and atrophic rhinitis, but not in pneumonias, moderate number of white spots in the liver, tail lesions, pyaemia, abscess/-es, peritonitis and polyarthritis.  相似文献   
12.
Data from the meat inspection at a large regional abattoir in Norway was used to study the effect of different production systems and herd size on the occurrence of pathological lesions in pig carcasses. Three production systems were compared: combined production, production strictly in batches and continuous production. Only the former reared its own piglets. The data was collected in the period 1975–1977. The number of herds varied between 87 and 94, and between 26,000 and 30,000 bacon pigs were slaughtered each year. The herds were divided into three different size groups: ≤ 200, 201–400, and > 400 pigs slaughtered annually. Each year was considered separately.The study showed that the highest frequency of sound carcasses occurred in the combined production group. There was no significant difference between the two production groups rearing purchased piglets. Moreover, there was an inverse relationship between the frequency of sound carcasses and herd size, but the positive effect of the small herd was estimated to be less important than that of production system.The distribution of 16 different pathological lesions was also considered. Four lesions (pneumonia — moderate and severe —, pleurisy and scabies) were recorded at significantly different levels in the production systems all three years of recording.Analysis of the effect of herd size also showed that in the cases of moderate pneumonia and pleurisy, the small herds were at an advantage. The other lesions had a rather casual distribution among the groups.The statistical evaluation indicates however, that in cases of significant differences between the tested groups, only 20–40 % of the variation could be “explained” by our model comprizing production systems and herd size groups.  相似文献   
13.
The influence of environment on animal health was studied in 40 bacon herds. These herds delivered approx. 11,000 baconers annually to the slaughter-house. The data from the meat inspection was studied in connection with the environmental recordings, and the relationship between 18 lesions and 20 environmental factors were estimated by statistical methods. The data was collected in the period 1975–1977.The influence of environmental factors upon the prevalence of different lesions showed considerable variation. Ten environmental factors were significantly associated with pleurisy and tail lesions (cannibalism). On the other hand none of the environmental factors bore any significant relation to atrophic rhinitis, pericarditis, peritonitis, perihepatitis, polyarthritis, arthritis and claw lesions. Eight environmental factors influenced the proportion of healthy animals.The recorded environmental factors influenced the overall health situation to a varying degree. For example, design of pen walls, insulation of pen floors, occasional use of supplementary feed and free access to drinking water were related to 5–7 lesions, while the nature of the concentrate (meal/pellets) had no significant influence.The study indicated that many details in environment and management could be of importance to the health of bacon pigs. However, statistical analysis also showed that production systems had a considerably stronger influence upon the health situation than any of the “pure” environmental factors – even when these factors were added.  相似文献   
14.
应用开发设计的昆虫声音采集与录制系统,对在不同实验条件下(玻璃板夹心、木段钻孔、室外直接测定)的红脂大小蠹两性成虫声音信号进行了采集、放大与数字化记录,并应用Adobe Audition与matlab软件分别对雌雄成虫的胁迫声、雄虫求偶声、雄虫竞争声、雌虫回应声等声音信号进行了脉冲组、频率、持续时间、频谱等特征分析,此外,还应用扫描电镜对其摩擦发声器官进行了观察与记录。研究结果表明:红脂大小蠹整体摩擦声音频率为35.3 kHz;雌雄间声音有显著区别,其摩擦发音结构音锉也有明显不同;而不同行为下所发出的声音信号在时域和频域上也略有差异,显示其与行为交流密切相关。  相似文献   
15.
家蚕蛾油对蛹虫草液体发酵培养的影响   总被引:1,自引:0,他引:1  
通过对蛹虫草菌丝体干产量以及胞外高分子聚合物和胞内多糖含量的测量分析,研究了添加家蚕蛾油对蛹虫草(Cordyceps militarisL.)液体发酵培养效果的影响。添加4%雄蚕蛾油或2%雌蚕蛾油,蛹虫草菌丝体的产量分别增加76.1%和45.9%,胞外高分子聚合物含量分别增加64.2%和43.0%,均达到最大值;添加3%雄蚕蛾油或雌蚕蛾油使胞内多糖含量分别增加46.8%和47.1%,菌丝体产量分别增加145%和102%,均达到最大值。结果表明,添加一定量的家蚕蛾油对蛹虫草液体发酵培养具有促进作用,而在作用效果上,家蚕雄蛾油要优于家蚕雌蛾油。  相似文献   
16.
根据近几年来学校电化教学室的使用情况和利用现代教育技术进行课堂教学的教师、学生提供的信息,结合电化教学实践经验,对幻灯、投影、教学录象及多媒体课堂教学系统等电教媒体的课堂教学效果进行了初步研究.  相似文献   
17.
基于信号特征分析的植物体表电信号记录模式选择   总被引:1,自引:0,他引:1  
为了探索不同耦合记录模式所记录植物体表波形数据特征,选择德抗961型小麦与含羞草2类植物,分别对每株植物进行直流耦合、交流耦合同步信号记录。分析光诱导下小麦所产生的局部电位中直流耦合记录与交流耦合记录的数据差异。小麦局部电位直流耦合与交流耦合记录数据波形峰峰值差异可达25倍以上;基于短时傅里叶变换,功率密度时频分布图显示直流耦合记录到的信号局部电位的频谱主要在0.2 Hz以内。而含羞草的变异电位的上述2种耦合模式记录的波形差异相对较小,功率密度时频分布图中可以反映其信号功率谱分布在0.6 Hz以内。通过记录不同下限截止频率的数据,小麦的光诱导电信号更加清晰的反映耦合方式对信号的影响,进一步地,通过含羞草变异电位的传导特性与对小麦钙通道阻滞的对照试验来验证所测信号的真实性。因此,针对不同植物及其植物电信号本身的特点,应选择适合的耦合记录方式。  相似文献   
18.
当今,精准农业技术已经越来越受到重视,同时随着劳动力成本的提高,越来越多的新技术新设备摆在了农民面前,如何将大量信息数据进行整合应用成为了摆在农民面前的问题。智能农业正是在这种情况下提出的。该文从6个方面介绍了智能农业的概念、发展方向以及目前应用状况,同时也阐明了发展中存在的问题。  相似文献   
19.
蛋鸡发声音频数据库的构建与应用   总被引:8,自引:7,他引:1  
蛋鸡发声含有丰富的机体信息,充分挖掘其声学特性,并利用其无接触、无应激的优点,为建立基于发声信息的蛋鸡养殖远程监测平台提供基础依据。该研究借助音频数字化处理技术和数据库管理平台,以海兰褐蛋鸡为例,搭建系统分别采集其在小规模(5只)饲养条件下的叫声信息及其体态行为。运用音频处理软件Adobe Auditionv1.0和音频分析软件Praat5.3提取蛋鸡发声特征参数,包括持续时间、基音频率、频谱质心、共振峰及其衍生的统计值,以此构建出蛋鸡发声音频数据库,在此基础上分别选取蛋鸡产蛋行为发声、鸣唱声和鸣叫声等典型发声行为对比分析。结果表明,蛋鸡产蛋行为发声与鸣唱声均为多次重复的、有节奏的、短促的音节所构成(称其为句子),前者先抑后扬、后者先扬后抑,句子的音节个数分别是7.8±2.0、15.2±7.7,但其时频域特征间存在着显著差异(P<0.05),与鸣叫声相比,其发声特征参数如频谱质心、共振峰等有着显著差异。研究表明,掌握蛋鸡发声的含义,有助于了解其行为特性、机体状态以及种群间的信息传递,并为蛋鸡行为特征识别与数字化监测平台的构建提供数据支持。  相似文献   
20.
实验得出适合膜片钳实验的耐盐木本植物中国沙棘子叶原生质体的游离条件,即取当天脱壳的子叶,放入渗透浓度为0.88 mol/L,pH为5.8,酶液的组分为10 g/LCellulase R-10、0.5 g/LPectolyase Y-23、1.5 g/LMacrozymeR-10、1 g/L Hemicellulase、1 g/L BSA、1 g/L PVP-40、2 mmol/L CaCl2、10 mmol/L Mes和5 mmol/L Vc的溶液中,在26℃、黑暗条件下,静置4 h。并且利用Multiclamp 700B放大器和Clampex 9.2软件,记录到了该原生质体质膜全细胞内向K 通道电流(-459.137 pA及-290.527 pA)和非选择性阳离子通道的外向电流(8.036 pA)。这为沙棘属木本植物细胞的电生理特性及其耐盐性机制关系的研究奠定基础。  相似文献   
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