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91.
Lameness remains a common cause of retirement in the equine athlete and among hobby enthusiasts. The distal limb is one of the most frequently imaged areas, and recent advances in diagnostic imaging capabilities help practicing veterinarians differentiate normal variants from informative pathology. Although acute, non–weight-bearing lameness is commonly associated with etiologies, such as fractures, abscesses, and laminitis, other uncommon differentials such as cystic lesions and neoplasia might also be considered. This report describes the characterization of a large, cystic lesion in the third phalanx (P3), which resulted in an acute, pathologic fracture. The lesion was fully characterized with the use of postmortem magnetic resonance imaging, gross pathology, and histopathology.  相似文献   
92.
An 18-year-old Appaloosa stallion presented with a history of ejaculatory dysfunction, which had recently progressed to an inability to ejaculate (anejaculation). Transrectal ultrasound evaluation revealed the presence of a prominent midline cyst of the colliculus seminalis, which was compressing the most terminal parts of the deferent ducts. Both ducts were enlarged and filled with hyperechoic content. The stallion was diagnosed with a complete occlusion of the deferent ducts because of the compression from the midline cyst of the colliculus seminalis. To date, there are no established treatments for this condition in stallions, although several procedures have been successfully used in men affected by similar problems. Therefore, we proposed performing one of these procedures—a laser ablation of the cyst to collapse it and to open the ejaculatory path. The stallion was placed under general anesthesia, and an endoscopic ultrasound-guided laser ablation of the cyst was performed. No immediate or long-term complications were observed. After the expulsion of accumulated material, the stallion produced normal semen and successfully impregnated mares during the next breeding season.  相似文献   
93.

Root-knot nematodes cause substantial economic loss of yield in coffee plantations and vegetable crops in Cuba. At present, methods to control the nematodes are ineffective or inappropriate and alternatives are being sought. The nematophagous fungus Verticillium chlamydosporium (Goddard) was isolated from soils collected from coffee plantations and infected root-knot nematode eggs from roots of tomato plants grown in these soils. A total of 83 isolates were collected and identified morphologically as V. chlamydosporium var. chlamydosporium, V. chlamydosporium var. catenulatum, V. psalliotae, V. suchlasporium and an isolate of V. chlamydosporium var. chlamydosporium with unusually large dictyochlamydospores. From these, 24 that represented a range of origins were selected and screened for their ability to parasitize eggs of root-knot nematodes, colonize the rhizosphere of barley roots and produce chlamydospores. None of the isolates grew at temperatures below 15°C and V. suchlasporium grew at a faster rate at lower temperatures than the other isolates. These were also screened in the glasshouse and V. chlamydosporium var. catenulatum caused the greatest reduction in nematode populations. One isolate of each subspecies of V. chlamydosporium was tested with the standard, Rothamsted isolate 10, on a range of host plants. The greatest reduction in numbers of nematodes occurred on tomato plants (cv. Pixie). The Rothamsted isolate 10 reduced numbers of nematodes toa greater extent than the other isolates, and therefore has the greatest potential as a biological control agent of root-knot nematodes.  相似文献   
94.
Nematodes of the genuses Strongylus and Setaria are able to erratically migrate to the equine testis and provoke characteristic inflammatory changes. Moreover, the presence of living parasites in scrotal testes is a scarce finding in which only the tracts and related lesions may be observed. In a 20-year experience of equine testes observed in abattoirs, 13 cases of atypical inflammatory lesions in scrotal testes were collected. On opening of the vaginal cavity, hydrocele was consistantly observed, and the Morgagni's appendix was enlarged, prominent, and reddish. Large, elongated, or irregular prominent red to yellow areas were visible on the testicular or epididymal serosa. Edematous enlargement of the epididymal head or tail was occasionally observed. In two cases, the described lesions were detected together with nematodes of the species Setaria equina, free and viable or encapsulated in the visceral and parietal layers of the tunica vaginalis, confirming the hypothesized cause. Histologically, the serosal lesions were interpreted as parasitic tracts, characterized by hemorrhage and leukocyte infiltrates in recent lesions or by granulation tissue with numerous macrophages in elderly ones. In the latter, areas of squamous metaplasia could be observed in the appendix testis and in the epididymal duct. Associated microscopic lesions included diffuse periorchitis, lymphocytic interstitial orchitis with mild to severe degeneration of seminiferous tubules, and vasculitis, epididymitis, and sperm granuloma.  相似文献   
95.
Mucin hypersecretion is considered to be one of the most common components of the immune response to gastrointestinal nematode infection. However, investigations have not been conducted in the Cattle–Cooperia oncophora system to verify the findings largely derived from murine models. In this study, we examined the expression of seven mucins and seven enzymes in the mucin biosynthesis pathway involved in O-linked glycosylation in the bovine small intestine including goblet cells enriched using laser capture microdissection during a primary C. oncophora infection. At the mRNA level, MUC2 expression was significantly higher in both lamina propria and goblet cells at 28 days post-infection compared to the naïve control. MUC5B expression at the mRNA level was also higher in lamina propria at 28 dpi. Expression of MUC1, MUC4, MUC5AC, and MUC6 was extremely low or not detectable in goblet cells, columnar epithelial cells, and lamina propria from both naïve control and infected animals. Among the seven enzymes involved in post-translational O-linked glycosylation of mucins, GCNT3, which may represent one of the key rate-limiting steps in mucin biosynthesis, was up-regulated in goblet cells, columnar epithelial cells, lamina propria, and gross small intestine tissue during the course of infection. Western blot analysis revealed that MUC2 glycoprotein was strongly induced by infection in both gross small intestine tissue and its mucosal layer. In contrast, the higher MUC5B protein expression was observed only in the mucosal layer. Immunohistochemistry provided further evidence of the mucin glycoprotein production and localization. Our results provided insight into regulation of mucin biosynthesis in various cell types in the bovine small intestine during gastrointestinal nematode infection and will facilitate our understanding of mucins and their role in immune response against parasitic nematodes.  相似文献   
96.
One of the key issues in compost research is to assess when the compost has reached a mature stage. The maturity status of the compost determines the quality of the final soil amendment product. The nematode community occurring in a Controlled Microbial Composting (CMC) process was analyzed with the objective of assessing whether the species composition could be used as a bio-indicator of the compost maturity status. The results obtained here describe the major shifts in species composition that occur during the composting process. Compared to terrestrial ecosystems, nematode succession in compost differs mainly in the absence of K-strategists and numerical importance of diplogastrids. At the beginning of the composting process (thermophilic phase), immediately after the heat peak, the nematode population is primarily built by bacterial feeding enrichment opportunists (cp-1) (Rhabditidae, Panagrolaimidae, Diplogastridae) followed by the bacterial-feeding general opportunists (cp-2) (Cephalobidae) and the fungal-feeding general opportunists (Aphelenchoididae). Thereafter, during the cooling and maturation stage, the bacterial-feeding-predator opportunistic nematodes (Mononchoides sp.) became dominant. Finally, at the most mature stage, the fungal-feeding Anguinidae (mainly Ditylenchus filimus) were most present. Both, the Maturity Index (MI) and the fungivorous/bacterivorous ratio (f/b ratio), increase as the compost becomes more mature (ranging, respectively, from 1 to 1.86 and from 0 to 11.90). Based on these results, both indices are suggested as potential suitable tools to assess compost maturity.  相似文献   
97.
Cyanobacteria or blue green algae are prokaryotic oxygenic phototrophs that require little moisture and diffused light for growth and are ubiquitous in nature. Both the heterocystous and non-heterocystous forms of cyanobacteria are reported to produce a large number of compounds with varying bioactivities including toxins such as microcystins, nodularins and neurotoxins. Extracts and exudates of cyanobacteria have been reported to inhibit hatching and to cause immobility and mortality of juvenile plant parasitic nematodes in vitro. Application of cyanobacteria in soil may reduce nematode infestation and increase plant yield. There are reports of several cyanobacterial formulations that are being developed and tested against plant pathogens but none have been commercialised. Screening of extracts or metabolites against plant parasitic nematodes is the initial step to determine the usefulness of cyanobacteria for nematode management. Therefore, a large scale screening programme is necessary for selection of strains with greater nematicidal potential. The nitrogen fixation abilities of some species of cyanobacteria also render them useful as biofertilizers. A combination of nitrogen fixation and nematode suppressive attributes can provide a dual advantage in several crops. Future research is needed in this direction to exploit these organisms for biorational management of plant parasitic nematodes.  相似文献   
98.
在国家948项目的资助下,从美国引进了抗线辣椒,查尔斯顿圆椒。对该品种进行了培育技术和抗线性的研究。结果表明,在所述技术条件下,该品种生长良好,在其根部和行间的土壤线虫数量显著降低。表明该品种可以用来在种植林木苗木、蔬菜、花卉等作物时,通过间作、换茬和嫁接等方法控制土壤线虫。  相似文献   
99.
对西藏拉果错卤虫线粒体12S-16S rDNA片段进行了限制性片段长度多态性(RFLP)分析。对两个样本ARC1347和ARC1348分别分析了40和31个个体。应用PCR技术扩增了卤虫单个休眠卵的线粒体12S-16S rDNA,选用能识别四碱基的限制性内切酶Hpa Ⅱ、Nde Ⅱ、TaqⅠ和Hag Ⅲ对该基因片段进行RFLP分析。在两个样本中均各检测出5种单倍型,其中单倍型AAAA为两个群体所共有,并均以该单倍型为主,它的个体数所占的百分比在两个群体(ARC1347和ARC1348)中分别为85.0%和83.9%。ARC1347号样本各单倍型之间的平均遗传距离为0.0350,ARC1348号样本各单倍型间的平均遗传距离为0.0121;ARC1347和ARC1348样本的线粒体12S-16S rDNA的多态度(或称核苷酸多样性指数)π值分别为0.0052和0.0013。结果说明,西藏拉果错卤虫具有一定的群体内遗传多样性。  相似文献   
100.
抗线虫基因表达载体构建与转化甘蔗研究初报   总被引:4,自引:0,他引:4  
试验研究利用德国引进的抗线虫基因Hs1pro 1构建表达载体并转化甘蔗 (SaccharumofficinarumL .) ,以获得抗线虫转基因植株。提取克隆载体P1832用NcoⅠ酶切、Klenow补平和SacⅠ酶切 ,回收基因片段 ;提取表达载体pBIL 1用KpnⅠ酶切、T4DNApolymerase补平和SacⅠ酶切 ,回收大片段 ;目的片段用T4DNAligase连接并转化E .coli,鉴定重组质粒 ;用基因枪轰击转化甘蔗品种“ROC”16获得 16株再生苗 ,其中 4株经PCR检测呈阳性 ,通过Southern杂交 ,证明Hs1pro 1基因已整合到其中 3株甘蔗基因组中  相似文献   
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