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81.
Ashraf Sayed Awaad Mohamed Kamal Merai Abdel Maksoud Mohamed Zaki Fathy 《Anatomia, histologia, embryologia》2019,48(4):279-289
The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep. 相似文献
82.
Mandal SC Kohli MP Das P Singh SK Munilkumar S Sarma K Baruah K 《Fish physiology and biochemistry》2012,38(2):573-584
This study aimed to elucidate the effect of partial or complete replacement of live feed (LF) (Tubifex) with formulated feed (FF) on the reproductive performance of Betta
splendens. Three hundred B.
splendens fry (average weight 0.19 ± 0.01 g) were equally distributed into five different groups, each with three replicates. They
were fed for 105 days with following different diets: control (C)—100% LF; T1—75% LF, 25% FF; T2—50% LF, 50% FF; T3—25% LF,
75% FF, and T4—100% FF. Results showed that the average number of hatched larvae (654 ± 101) and fry survival after 2 weeks
of rearing (428 ± 70), after completion of three spawning, were recorded highest in the control group, which was, however,
not significantly different from the T1, T2, and T3 groups. At the end of the feeding trial, the highest hatching percentage
(90.3%) was registered in the T2 group, which was not significantly different from the control and T1 groups. The T2 group
also recorded highest fry survival (65.54%) after completion of three spawning, which was not significantly (P < 0.05) different from the T1 and T3 groups. Control diet contained higher saturated fatty acid (63.23%) than formulated
diet (29.80%). In the whole-body tissue, highest level of EPA (0.42%) and DHA (3.13%) were found in the T4 group followed
by T3 group. The DHA/EPA ration was recorded highest in the T2 group (10.96%), which did not differ significantly from the
T1 and T3 groups. Significant positive correlation was observed between saturated fatty acid levels in fish whole-body tissue
and number of hatched larvae (Y = 30.81 × −825.3, R
2 = 0.968) and fry survival after 2 weeks of rearing (Y = 21.38 × −580.9, R
2 = 0.967). Considering all these factors, it can be concluded that the live feed Tubifex can be replaced up to 50% without any adverse effect on the reproductive performance and fry survival of B. splendens. 相似文献
83.
Sidra Manzoor Asif Nadeem Javed Maryam Abu Saeed Hashmi Muhammad Imran Masroor Ellahi Babar 《Tropical animal health and production》2018,50(2):275-281
Osteopontin gene is regarded as a plausible candidate in mammary gland differentiation and development, expressed by variety of cells, tissues, and biological fluids including milk. The current study was performed in two phases. In the first phase, Osteopontin gene polymorphisms were identified and associated with milk composition such as ash, milk fat, SNF, lactose, and protein. In the second phase, milk samples from five healthy mastitis-free Nili Ravi buffaloes were analyzed for expression of Osteopontin gene at transition (day 15), mid (day 90), and end (day 250) stage of their second lactation. Briefly, blood samples were collected from Nili Ravi buffalo to isolate the genomic DNA, specific primers were designed for PCR amplification. The amplified PCR products were sequenced bi-directionally. Six polymorphisms were identified in the coding region and four in the intronic region of the gene. The results showed that SNP g.38329758 T > C causing substitution of valine to alanine (V127A) was associated with high milk protein. For mRNA expression analysis, somatic cells were separated from milk samples for RNA isolation. Analysis of differential gene expression data has permitted us to illustrate the expression pattern of osteopontin gene in lactating buffalo. The Osteopontin gene was found to be transcribed among all three lactation stages, but expression was observed with the highest value (fold change) in peak lactation and remained elevated till the end of lactation. Identified gene marker may be helpful for the prediction of superior animal for selection. The presented study also gave an insight into the genetic screening and lactation biology of riverine buffalo, offering direction for future research in lactating buffalo. 相似文献
84.
Jens Gebauer Yahia O. Adam Aida Cuní Sanchez Dietrich Darr Muneer E. S. Eltahir Kamal E. M. Fadl Gabriele Fernsebner Michael Frei Tsige-Yohannes Habte Karl Hammer Mauricio Hunsche Henry Johnson Maha Kordofani Michael Krawinkel Florian Kugler Eike Luedeling Tarig E. Mahmoud Anthony Maina Dagmar Mithöfer Chimuleke R. Y. Munthali Georg Noga Rabea North Willis O. Owino Kathleen Prinz Freda K. Rimberia Amina Saied Martin Schüring Anne Sennhenn Martin A. Späth Mohamed E. N. Taha Andreas Triebel Florian Wichern Martin Wiehle Nicole Wrage-Mönnig Katja Kehlenbeck 《Genetic Resources and Crop Evolution》2016,63(3):377-399
85.
Majid Aghaalikhani Majid Gholamhoseini Aria Dolatabadian Aydin Khodaei-Joghan Kamal Sadat Asilan 《Archives of Agronomy and Soil Science》2013,59(10):1149-1169
With regard to the low cation-exchange capacity and large saturated hydraulic conductivity of sandy soils, a field experiment was carried out in 2006–2007 to determine the impact of zeolite on nitrogen leaching and canola production. Four nitrogen (N) rates (0, 90, 180, and 270 kg ha–1) and three zeolite amounts (3, 6 and 9 t ha?1) were included as treatments. The results demonstrated that the highest growth parameters and seed yield were attained with 270 kg N ha?1 and 9 t zeolite ha?1. However, the highest and the lowest seed protein percentage and oil content were obtained with 270 kg N ha?1 accompanied by 9 t zeolite ha?1, respectively. Nitrate concentration in drained water was affected by nitrogen and zeolite. The lowest and highest leached nitrate values were found in control without N and zeolite (N0Z0) and in treatments with the highest N supply without zeolite (N270Z0), respectively. In general, nitrogen-use efficiency decreased with an increase in N supply. Application of 9 t zeolite ha?1 showed higher nitrogen use efficiency than other zeolite amounts. Also, application of more N fertilizer in soil reduced nitrogen uptake efficiency. In total, application of 270 kg N ha?1 and 9 t zeolite ha?1 could be suggested as superior treatment. 相似文献
86.
87.
Kamal Alskaf Debbie L. Sparkes Sacha J. Mooney Sofie Sjögersten Paul Wilson 《Soil Use and Management》2020,36(1):27-44
Reduced tillage systems have been argued to provide several potential benefits to soil, environment and to farm incomes. In England, while many farms have partially adopted such practices, a large proportion of arable farmers do not undertake reduced tillage in any form. This paper analyses the rationale for and uptake of different cultivation techniques, including analysis of the barriers to adoption of reduced tillage, aiming to benefit policymakers and researchers and increase the spread of smart agricultural practices. Based on a postal questionnaire, we estimated that 47.6% of English arable land is cultivated using minimum-tillage and 7% under no-tillage. As farm size increased, so did the probability of reduced tillage uptake. Furthermore, farms growing combinable crops were more likely to utilize reduced tillage approaches than other farm types. Soil type, weed control and weather conditions were noted as the main drivers for ‘strategic’ and ‘rotational’ ploughing, constraining continuous reduced tillage use. To effect greater reduced tillage uptake, greater communication between researchers and farmers is needed to facilitate the implementation of sustainable soil management solutions, supported by current legislation permitting responsible herbicide use in arable production. Financial support to access reduced tillage machinery may also be required for farmers operating smaller holdings. Adopting reduced tillage is a continuous learning process requiring ongoing training and information gathering; supporting a network of reduced tillage ‘farmer champions’ would facilitate practical knowledge exchange, allow farmers to observe soil improvements, understand transition phase barriers and ultimately encourage increased reduced tillage uptake. 相似文献
88.
Seham Haddad Ahmed E. Noreldin Basma Kamal Ahmed Abdeen Sameh M. Farouk Louise C. Abbott Mohamed Abdo 《Anatomia, histologia, embryologia》2019,48(5):404-414
Feral cats are considered as strays and are more likely to hunt in the street. We investigated the effect of environmental adaptations on the structures of lingual papillae in feral cats, which could be used as forensic evidence for their identification. There are no reported studies about the structural comparison of lingual papillae between suckling and adult feral cats. The present study described the lingual papillae of both suckling and adult cats macroscopically and microscopically via light and scanning electron microscopy. A total of nine tongue samples each for suckling and adult feral cats were examined grossly and histologically. Papillae distributions of suckling cats were similar to those observed in adult cats. Meanwhile, the shapes of those papillae were markedly different from that of corresponding papillae in adults. The change in taste bud position and size seemed to be related to the progressive growth of the papillae between adult and suckling cats; absence of taste buds in foliate papillae of feral cats at any stage; and marginal papillae which were a characteristic feature for all suckling cats. All previous elements could be affected by the specific feeding behaviour and mastication mode adaptation in suckling and adult feral cats which might help to identify suckling and adult feral cats among other breeds and animal species. We anticipate these findings may provide promising forensic evidence to discriminate between adult and suckling feral cat remains as well as prediction of environmental harshness and feeding behaviour. 相似文献
89.
90.
反相高效液相色谱法测定有机氯及含氮杀虫剂在水体·土壤沉积物及鱼体中的残留 总被引:6,自引:0,他引:6
Shahid Mahboob Ghazala S. Sultana Muhammad Rafique Asi S. Nadeem A.S. Chaudhry 《农业科学与技术》2009,10(5):9-12
[目的]测定水体、土壤沉积物以及鱼体内有机氯及含氮杀虫剂残留物,为科学评估杀虫剂残留对巴基斯坦地区公共卫生、农业和环境的影响提供依据。[方法]以食用鱼南亚野鲮为材料,设计2组体重,采用高效液相色谱法分别测定水体、土壤沉积物以及南亚野鲮体内α-硫丹、DDE、甲基对硫磷、异丙隆、呋喃丹、阿特拉津等含量。[结果]土壤沉积物中DDE的含量达(2.340±0.025)μg/g,在250~750g的南亚野鲮体内的含量分别为(0.270±0.0006)μg/g,但在水体中未发现DDE残留;不同饲料中农药残留物90%为有机磷、呋喃丹以及有机氯杀虫剂,6%为杀菌剂,仅4%为除草剂,在250~750g以及800~1300g的南亚野鲮体内硫丹的含量分别达到(0.491±0.0006)μg/g和(3.050±0.0608)μg/g,异丙隆的含量分别达到(0.010±0.0003)μg/g和(0.014±0.0006)μg/g,且随体重上升,其脂肪含量增加,积累的农药残留物则越多;硫丹、甲基对硫磷、阿特拉津和呋喃丹的含量在水体达到最大残留限量水平0.001μg/g。[结论]通过生物积累和在自然界中的运输以及再沉积作用,有机氯及其他杀虫剂的使用给全球的环境造成了严重污染,因此,在巴基斯坦已经禁止使用DDT等有机氯农药。 相似文献