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991.
The interaction of retention time in the rumen and concentrate diet on methane production in vitro and acetate:propionate ratio was examined. Twenty-four fistulated sheep were used in a complete factorial design with the sheep randomly divided into 4 groups. The sheep had a 5-wk acclimatization period on an oaten chaff diet, followed by two 3-wk diet phases. Two of the 4 groups were maintained on the oaten chaff diet for the duration of the experiment, with pot scrubbers added to the rumen of 1 of the 2 groups. The remaining 2 groups were offered a low-grain diet (35% grain) in the first diet phase followed by a high-grain diet (70% grain) in the second diet phase. Pot scrubbers were also added to the rumen of 1 of these 2 groups of grain-fed sheep. Pot scrubbers in combination with a low-grain diet decreased the amount of methane produced in vitro from 4.25 to 3.71 mmol/mL of digesta when compared with oaten chaff-fed sheep without pot scrubbers (P < 0.05). The acetate:propionate ratio was 1.6 in sheep fed a high-grain diet with pot scrubbers compared with 2.4 in sheep fed a high-grain diet without pot scrubbers in their rumen (P < 0.05). At high levels of grain, when employing a multivariate statistical analysis including all data, sheep given the combined treatment of grain and pot scrubbers were different from all other sheep groups in this experiment (P < 0.05). Furthermore, sheep fed a high-grain diet were different from sheep receiving the oaten chaff diets with and without pot scrubbers (P < 0.01 and P < 0.05, respectively). In conclusion, pot scrubbers combined with grain alter the rumen fermentation, and introducing pot scrubbers into the rumens of livestock consuming low levels of grain may be a way to lower methane emissions.  相似文献   
992.
OBJECTIVES: The aim of this study was to identify clinical features that could be used to identify individual dogs within the Guide Dogs for the Blind Association canine population at risk of being diagnosed as atopic in the future before they had fully developed the condition. METHODS: Clinical histories of atopic and non-atopic dogs from the Guide Dogs for the Blind Association population were analysed and statistically significant differences identified between the two groups. RESULTS: Atopic dogs were consistently affected by skin disease at a younger age than non-atopic dogs and that there was a significant difference in event curves between atopic and non-atopic dogs at 10 months of age. From a predictive point of view, dogs that suffered from four or more episodes of atopic-type skin disease by the age of 15 months were at an increased risk of developing atopic dermatitis. CLINICAL SIGNIFICANCE: It is suggested that the clinical history of all dogs from the Guide Dogs for the Blind Association about to undergo training should be examined for these factors to assess whether or not they should undergo training.  相似文献   
993.
Feline myeloma-related disorders (MRD) are rare neoplasms of plasma cells. The multistep transformation model of myeloma in humans is based on the premise that plasma cells undergo neoplastic transformation primarily within the intramedullary compartment and that over time they become poorly differentiated and metastasize to extramedullary locations. Historically, diagnostic criteria used for human multiple myeloma have been applied to the cat, with the assumption that feline MRD commonly arises in the intramedullary compartment. Our objectives were to describe the features of feline MRD confirmed by cytology, histopathology, histochemistry, and immunohistochemistry and to categorize these tumors. A priori hypotheses were 1) tumor category predicts survival and 2) cats with well-differentiated tumors commonly have extramedullary involvement in contrast to human myeloma patients. This multicenter, retrospective study identified 26 MRD cases. There was good agreement between histopathologic and cytologic tumor categorization. Histochemistry and immunohistochemistry were shown to be valuable adjunct tests in the diagnosis of MRD. Cats with well-differentiated tumors had increased median survival relative to those with poorly differentiated tumors (254 versus 14 days). We have reported that marked extramedullary involvement at initial clinical presentation is significantly more common in the cat than in human MRD patients. In this study, we demonstrate that cats with well-differentiated tumors more commonly have extramedullary involvement than human myeloma patients with well-differentiated tumors (90% versus 20%, P < 0.0002). These results contrast strongly with the human myeloma model of primary intramedullary neoplastic transformation and suggest that primary extramedullary neoplastic transformation may be more common in feline MRD.  相似文献   
994.
正随着教育的改革与深化,英语语言学习在高等教育中起着至关重要的作用。各院校为了明确办学目的和专业定位,在公共英语教学中,专业英语的学习与教学任务逐渐受到重视。采用通用英语教学(EGP)和特殊用途英语教学(ESP)相结合的教学模式,使得高校英语教学逐步形成科研型、职业型相结合的体制,对高校专业人才培养和学生的执业能力提高起到了重要作用。文章在简要总结和归纳了EGP和ESP概念的基础上,以动物医学专业的专业英语教学为主线,从一定程度上分析了动  相似文献   
995.
基于气候适宜度的贵州番茄精细化农业气候区划   总被引:4,自引:0,他引:4  
利用贵州省81个气象台站1961—2015年的温度、降水和日照等气象资料,建立番茄不同生育期的温度、降水和日照的气候适宜模型,并采用相对权重法计算了番茄整个生育期的综合气候适宜度。结果表明:全省温度适宜度空间呈东高西低、南高北低趋势,变化范围为0.42~0.97,降水充沛,降水适宜度较高,变化范围为0.78~1.00,日照适宜度在0.54~0.98,呈西高东低的分布特征;贵州省番茄适宜种植区的总面积为17.2万km2,其中最适宜区面积为4.25万km2,主要分布在黔西南州、六盘水南部、安顺市西部、南部边缘及遵义市北部边缘地区,约占全省面积的24.14%;适宜区主要集中在贵阳市、毕节市、遵义市、铜仁市和黔东南州大部及黔南州北部等地区,约占全省面积的73.49%。  相似文献   
996.
沼肥防治小麦全蚀病初探   总被引:1,自引:0,他引:1  
山东省昌邑县连续两年用沼肥防治小麦全蚀病取得明显效果。试验表明,施用沼肥的小麦全蚀病发病期出现晚,病株率显著减少。与施土杂肥对比,施沼肥的小麦全蚀病率在2%左右,而施土杂肥的发病率达50%以上。试验结果如下表。  相似文献   
997.
Rabies is diagnosed by FAT in the impression smears of brain tissues. In this study, an attempt was made to diagnose rabies using in situ polymerase chain reaction (ISPCR). A digoxigenin-labelled double-stranded probe specific for a portion of the ‘N’ gene of rabies virus was used. Positive signals were identified as blue dots in the intraneuronal and neuropil areas.  相似文献   
998.
999.
Diarrhoea in growing and finishing pigs is usually caused by infectious agents and laboratory diagnosis is a prerequisite for efficient therapy. Cultivation of Brachyspira hyodysenteriae or Brachyspira pilosicoli and detection of Lawsonia intracellularis by means of immunofluorescence tests (IFT) are time-consuming and in some cases lack sensitivity. A multiplex-PCR was designed to detect simultaneously these three pathogens in faeces and tissue samples, allowing the differential diagnosis of dysentery, intestinal spirochaetosis and proliferative enteropathy. Detection limits for B. hyodysenteriae, B. pilosicoli and L. intracellularis were 10(4), 10(2) and 10(3) copies respectively. Agreement between multiplex-PCR and nested-PCR or cultivation was considered substantial to almost perfect. Agreement between multiplex-PCR and IFT in detecting L. intracellularis was only moderate, which was probably related to false-positive results given by IFT. The multiplex-PCR described herein is a valuable tool for the rapid and simultaneous detection of three different pathogens in porcine samples causing enteric diseases.  相似文献   
1000.
This is the first report of feline solitary plasmacytoma of bone. We describe the clinical, clinico-pathological, radiographic and pathological findings of two successfully treated cats with long-term follow-up. The first case presented with spinal pain and neurological deficits. Radiographs demonstrated sclerosis of lumbar vertebra L6 and a myelogram confirmed interference to flow of contrast in the L4-7 region. A biopsy of L6 revealed neoplastic plasma cell infiltration. There was no evidence of paraproteinaemia on serum protein electrophoresis. The cat underwent hypofractionated megavoltage radiotherapy. Clinical signs resolved completely and 4 years after diagnosis the cat remains well and has no electrophoretically detectable paraproteinaemia. The second case presented with neurological deficits of the tail and spinal radiographs revealed extensive osteolysis of the sacrum. A biopsy of sacral bone demonstrated neoplastic plasma cell infiltration. The animal was normoglobulinaemic. The cat improved clinically with induction chemotherapy (melphalan and methylprednisolone). The same chemotherapeutics were continued at maintenance doses for 4.3 years, at which time there was recurrence of neurological deficits and a palpable sacral mass. Cytological examination of a fine needle aspirate confirmed recurrence of plasma cell neoplasia. A low concentration monoclonal paraproteinaemia was detected. Vincristine was administered resulting in resolution of neurological deficits and a palpably smaller sacral mass. Eighteen months into vincristine therapy, there was recurrence of clinical signs and the cat was euthanased, more than 6 years after the initial diagnosis.  相似文献   
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