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101.
Mohamed A. M. Alsafy Samir A. El-Gendy Basma Kamal 《Anatomia, histologia, embryologia》2021,50(1):108-113
The objective of the current study was to describe the structures of the pastern and coffin joints in dromedary camel using x-ray, bone and soft tissue windows computed tomography (CT) and three-dimensional volume rendering (3DVR) of CT imaging. 3DVR of CT was obtained at the slight flexed dorsal view, plantar view, dorsolateral view and lateral view which explained all the surfaces and structures of the digit bony parts even the parts of the articular surface. The processed images of 3DVR of CT showed different patterns of the cortical, cancellous, subchondral bones and medullary cavity of the bones of the digits. The present study showed clearly all the hard and soft tissues in the pastern and coffin joints of the camel in CT images; however, the plantar ligaments of the pastern joint and ligaments of the navicular cartilage identified on CT images. The CT soft tissue window visualized the joint cavity and their pouches and tendon sheath of the flexor tendons better than the bone window CT. The radiographic, CT and 3D images could be used as a normal reference for the interpretation of some clinical diseases in the pastern and coffin joints of the camel. 相似文献
102.
Abdel-Moneim AM El-Saad AM Hussein HK Dekinesh SI 《Journal of aquatic animal health》2012,24(3):148-160
Various oxidative stress and histopathological biomarkers in gill tissues of Nile tilapia Oreochromis niloticus were investigated. Fish were collected from four sites that differ in their extent of pollution load, including heavy metals: the southeast basin (SEB), main basin (MB), and northwest basin (NWB) of Lake Mariut; and Boughaz El-Maadiya, a channel in Lake Edku. The oxidative stress biomarkers that were analyzed included lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), and glutathione redox cycle enzymes (glutathione peroxidase [GPx] and glutathione reductase [GR]). Levels of reduced glutathione (GSH) were also evaluated. Gill morphology was analyzed by light microscopy and scanning electron microscopy (SEM). Gill LPO was significantly higher in gill tissues of fish collected from the more heavily contaminated MB (40.0%) and NWB (51.4%) sites than in gill samples from the less-contaminated (reference) site, the SEB. Gill LPO in fish from Lake Edku was intermediate but was not significantly higher (17.1%) than the reference. The activities of antioxidant enzymes and the redox-sensitive thiol compound GSH were significantly lower in gill samples from the disturbed sites than in samples from the reference site. Specifically, SOD in MB, NWB, and Lake Edku samples; CAT and GPx in NWB samples; and GR activity and GSH content in MB and NWB samples were lower than those in SEB samples. In most cases, gill tissues from Lake Edku fish had intermediate levels of antioxidants. The main histopathological alterations observed in gills were epithelial lifting, hyperplasia and hypertrophy of the respiratory epithelium, lamellar fusion, and aneurysms. In addition, SEM results demonstrated transformation of the surface structure of epithelial pavement cells. Pathological reactions in the gills of Nile tilapia were most severe at the MB and NWB sites. Our findings suggest that Nile tilapia responded differently according to the environmental stress index in each sampling area. This study is the first to report gill oxidative stress and histopathologies in Nile tilapia from Egyptian aquatic environments. 相似文献
103.
Kobayashi Y Ogawa A Sato G Sato T Itou T Samara SI Carvalho AA Nociti DP Ito FH Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1097-1100
Seventy-seven rabies virus (RV) isolates originating from Brazilian cattle were genetically characterized. Partial nucleoprotein gene sequences of these isolates were phylogenetically and geographically analyzed. Cattle isolates, which clustered with the vampire bat-related RV group, were further subdivided into nine genetic subgroups. These subgroups were distributed widely in lowland regions, with some subgroups separated from each other by mountain ranges. In addition, separation of the groups in mountainous regions was correlated with altitude. These results indicate that cattle rabies is derived from several regionally-defined variants, which suggests that its geographical distribution is related to that of the vampire bat population. 相似文献
104.
We compared performance (growth, survival, and condition) of northern largemouth bass Micropterus salmoides salmoides fingerlings fed one of three commercial starter feeds: Otohime Marine Weaning (OMW; Marubeni Nisshin Feed), Bio-Oregon BiVita Fry (BVF; Bio-Oregon), and Purina Aquamax Starter (PAS; PMI Nutrition International LLC). Nine 833-L circular tanks, connected in parallel to a recirculation system, were stocked with 465 fish (1.4 kg), each to provide a rearing density of 1.1 fish/L. Water temperature was maintained at 27°C, and photoperiod was 15:9 h light:dark. Feed sizes (1.5–1.6 mm) were comparable and had similar protein composition (48%–50%). Feed was dispensed by vibratory feeders at a rate of 5% BWPD from 0730 h to 2130 h every 0.5 h for a total of 29 feedings per day (trial duration = 22 days). Overall performance was best for fish fed OMW, followed by BVF, then PAS. The PAS feed resulted in significantly lower growth, survival, and condition factor (P ≤ 0.05). Though not statistically significant, the BVF feed resulted in lower growth, condition factor, and survival than OMW (P > 0.05). Performance measures were positively correlated with crude fat and negatively correlated with protein to energy ratio of feeds. The OMW or BVF diets may be more appropriate for intensive culture when the artificial feed is the sole food supply, while the PAS diet may be more suitable for extensive culture as a supplemental food source. 相似文献
105.
Samir A. Aboulroos 《植物养料与土壤学杂志》1975,138(6):551-562
Natrium - (Calcium + Magnesium) - Austauschgleichgewichte in Böden . Beckett's approach has been used to describe the Na-(Ca + Mg) exchange isotherm in twenty soil samples that differed in texture and salinity. The data obtained from the isotherms were compared with the values of exchangeable sodium obtained by ammonium acetate and the concentration ratios (Na/ °Ca+Mg) calculated from the saturation paste extract. The Na-Q/I relation was always linear for each of the studied soils with no curvature at the lower values of concentration ratio. Values of - Δ Na0 obtained from the isotherms were highly correlated with exchangeable Na (r2 + 0.89). The equilibrium concentration ratios of the isotherms were similar to those obtained from the saturated paste extract in the non-saline soils, and were much lower in the case of the salt affected soils. The slope of the Na-Q/I relation appeared to be a soil characteristic not affected by either Na depletion from the soil or Na addition up to 5 me./100 g. soil. The PBCNa values were highly correlated with the C.E.C. values of the soil (r2 + 0.97). 相似文献
106.
Igor Renan Honorato Gatto Daniel Correia Lima Linhares Henrique Meiroz de Souza Almeida Luis Antônio Mathias Andrea Souza Ramos de Medeiros Zvonimir Poljak Samir Issa Samara Luis Guilherme de Oliveira 《Tropical animal health and production》2018,50(4):773-778
Bovine viral diarrhea virus (BVDV) infects ruminants as primary hosts. However, other animals like pigs are susceptible. This study was conducted to investigate seroprevalence and risk factors associated with the detection of BVDV antibodies in pig herds. A total of 1.705 serum samples of 33 finisher herds, from seven Brazilian states, were collected in slaughterhouses. The samples were tested by virus neutralization (VN) test. In total, 5.35% (91/1.705) were positive and 64% (21/33) of the herds had positive animals. A significant association with “trucks are not cleaned and disinfected” and “visitors do not respect 72-h interval between visits to farms” (P?<?0.05) was found in association with detection of BVDV-2 antibodies. This study suggests that important biosecurity gaps are present in Brazilian pig farms, as the presence of BVDV antibodies in pigs suggests (direct or indirect) contact with population(s) of ruminant species. Closing biosecurity gaps prevents spread of BVDV and other pathogens such as foot-and-mouth disease virus (FMDV) between pig and ruminant farms. This data should be taken in account by CSF surveillance programs, once cross-reaction in serologic tests between classical swine fever virus (CSFV) and BVDV antibodies has been shown to occur. 相似文献
107.
Suman Bhusan Chakraborty Samir Banerjee Saibal Chatterjee 《Aquaculture International》2011,19(6):1119-1137
The aim of this study was to investigate the molecular mechanism behind androgen-induced sex reversal and growth increase
in Nile tilapia. Three-day-old mixed-sex tilapia juveniles were treated with differential dose (0, 5, 10, 20, 30 mg/kg diet)
and duration (0, 15, 30, 45, 60 days) regimes of 17α-methyltestosterone. Treatment regimes 10, 20, 30 mg/kg-30, 45, 60 days
showed ~95% males, while 0 mg/kg-0 days (control) showed ~50% males (P < 0.01). Next, tilapia was cultured for 6 months in cistern and pond culture systems with 17α-methyltestosterone-treated
diet (10 mg/kg) for three different durations: 0 days (control), 30 days (30-day-treated), and 180 days (throughout-treated).
Fish in pond culture showed significantly higher (P < 0.05) final weight compared with tilapia in cistern culture (235.76, 156.82 g, respectively). Both 30-day-treated and throughout-treated
fish showed significantly higher (P < 0.05) final weight, length, daily weight gain, specific growth rate, and muscle protein content compared with control fish.
The androgen receptor β mRNA and protein expression levels in both 30-day-treated and throughout-treated fish were significantly
higher (~twofolds, P < 0.05) compared with hormone-untreated control males. However, there was not much difference for all these parameters among
the two hormone-treated groups. This higher growth probably results from an androgen-induced increased ‘androgen-androgen
receptor’ mediated anabolic pathway. Serum testosterone concentration of 30-day-treated fish after 6 months was similar to
that of control males (0.9 ng/ml). Moreover, culture of 17α-methyltestosterone-treated monosex tilapia was found beneficial
than hormone-untreated mixed-sex tilapia culture for maintenance of natural fish diversity in indigenous water bodies. 相似文献
108.
蜜瓜和西瓜果汁的射频介电特性及其与糖度的关系 总被引:2,自引:2,他引:2
为了解果汁的介电特性与其主要内部品质──糖度之间的关系,该文利用末端开路的同轴探头和阻抗分析仪测量了10MHz~18GHI的频率范围内不同成熟度的3个品种密瓜汁和4个品种西瓜汁的介电特性,同时测量了反映果汁糖度的可溶性固形物含量和果肉的含水率,分析了介电特性和糖度间的关系.结果显示:密瓜和西瓜果汁的相对介电常数和介质损耗因数皆随频率的增大单调减小,品种间的差异对介电特性有影响;1.8GHz下密瓜汁的损耗角正切与糖度有较好的线性关系,其决定系数为0.784,但西瓜汁的介电特性与糖度的相关性较差;密瓜和西瓜果汁的糖度与果肉的含水率有很好的线性相关性,其决定系数分别为0.973和0.906.该研究将为基于介电特性的果汁糖度检测仪的开发提供了研究基础. 相似文献
109.
Leonardo Schena Antonio Ippolito Tirtza Zahavi Lea Cohen Samir Droby 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(7):681-691
Nineteen yeast isolates obtained from the surface of several fruits and vegetables grown in Southern Italy and Israel were compared by molecular analysis using arbitrarily primed polymerase chain reaction (AP-PCR) and random amplified polymorphic DNA technique (RAPD-PCR). Genetic analysis made it possible to distinguish between closely-related genitically different strains which had the same morphological characteristic, and to discard isolates which were genetically identical. Following PCR characterisation, 6 isolates were selected and tested for their biocontrol activity against major postharvest pathogens (Penicillium digitatum on grapefruit, Botrytis cinerea, Rhizopus stolonifer and Aspergillus niger on table grape and B. cinerea and R. stolonifer on cherry tomato). All the isolates showed a good biocontrol efficacy on both wounded and non-wounded fruits. Furthermore, the preharvest application of the most effective antagonist (LS15) on table grape resulted in a significant reduction in grey mold ranging from 28.3% to 38.2% compared to the untreated control. The RAPD-PCR technique was also useful for identifying and monitoring the survival of the antagonist after field application. 相似文献
110.