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81.
The Usefulness of Captive Kept Capercaillie (Tetrao urogallus L.) as the Semen Donors for Artificial Insemination and Gene Pool Preservation In vitro 下载免费PDF全文
Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106 per ml to 3520 × 106 per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons. 相似文献
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Interfacial charge-transfer rate constants have been measured for n-type Si electrodes in contact with a series of viologen-based redox couples in methanol through analyses of the behavior of these junctions with respect to their current density versus potential and differential capacitance versus potential properties. The data allow evaluation of the maximum rate constant (and therefore the electronic coupling) for majority carriers in the solid as well as of the dependence of the rate constant on the driving force for transfer of delocalized electrons from the n-Si semiconducting electrode into the localized molecular redox species in the solution phase. The data are in good agreement with existing models of this interfacial electron transfer process and provide insight into the fundamental kinetic events underlying the use of semiconducting photoelectrodes in applications such as solar energy conversion. 相似文献
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H. Bagnall-Oakeley C. Conroy A. Faiz A. Gunawan A. Gouyon E. Penot S. Liangsutthissagon H. D. Nguyen C. Anwar 《Agroforestry Systems》1996,36(1-3):83-104
A large proportion of global natural rubber production takes place in Southeast Asia. The majority of this rubber is produced by smallholders. Thailand, Indonesia and Malaysia are the three principal countries involved. In Malaysia and Indonesia the smallholder sector accounts for 72% and 84% of total rubber production respectively. In other countries rubber plays a significant role on a more local basis. Imperata is a serious problem for the smallholder rubber farmer in most of Southeast Asia in three respects: the high cost (labour and/or capital) of opening Imperata-infested land, its competitive effect on rubber and annual intercrops, and the fire hazard that it poses during the dry season as a major source of combustible material. The costs of Imperata to smallholders are substantial in terms of a direct loss through fire and revenue foregone or delayed as a result of competition. Most smallholders intercrop their rubber during the first 1–3 years after planting it, and during this period Imperata is reasonably well controlled. Intercropping is only feasible for a limited period because of limited soil fertility and/or the shading effect of the rubber trees. After intercropping, Imperata tends to establish itself for a few years until it too is shaded out by the rubber. This is the problem period, during which farmers practise only limited weed management, if any.A large amount of research has been done on methods of controlling Imperata, but the recommended methods have been generally spurned by smallholders unless they have been given subsidies to apply them. This paper describes the precise nature of the Imperata problem, with reference to some of the smallholder rubber-based farming systems within Southeast Asia; the different Imperata control strategies currently practised in these farming systems; and some of the constraints on the adoption of currently and recently recommended practices. It then proposes a ten-point agenda for research on Imperata control, including two ways in which current research programmes could be usefully reoriented: first, they need to take greater account of smallholder farming systems and constraints; and second they should shift their emphasis from single-method to integrated control systems. 相似文献
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The major impacts of bovine viral diarrhoea (BVD) on cattle health and production have prompted many countries to embark on national elimination programmes. These programmes typically involve identifying and removing persistently infected (PI) cattle in infected herds and implementing biosecurity measures, such as pre- or post-movement testing. In order to design a systematic national control programme to eliminate BVD in New Zealand, which achieves the greatest benefits to the industries at the lowest cost to individual farmers, an accurate understanding is necessary of the epidemiology, economics and social motivation for BVD control in New Zealand. In this article we briefly review the pathogenesis of BVD, transmission and diagnosis of BVD virus infection, and effectiveness of vaccination. We summarise the current state of knowledge of the prevalence, risk factors for transmission, and financial impacts of BVD in New Zealand. We describe control programmes in Europe and then discuss the challenges that must be addressed to design a cost-effective national control programme to eliminate BVD in New Zealand. 相似文献
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Seppo AM Saari Kirsi H Juuti Joanna H Paloj?rvi Kirsi M V?is?nen Riitta-Liisa Rajaniemi Leena E Saijonmaa-Koulumies 《Acta veterinaria Scandinavica》2009,51(1):40
Background
Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation.Case presentation
We describe D. gatoi in 10 cats, including five Cornish Rex, two Burmese, one Exotic, one Persian and one Siamese, living in six multi-cat households in different locations in Finland containing 21 cats in total. Intense pruritus was the main clinical sign. Scaling, broken hairs, alopecia and self-inflicted excoriations were also observed.Diagnosis was based on finding typical short-bodied demodectic mites in skin scrapings, skin biopsies or on tape strips. Other pruritic skin diseases, such as allergies and dermatophytoses, were ruled out. In one household, despite finding several mites on one cat, all six cats of the household remained symptomless.Amitraz used weekly at a concentration of 125-250 ppm for 2-3 months, proved successful in three households, 2% lime sulphur weekly dips applied for six weeks in one household and peroral ivermectin (1 mg every other day for 10 weeks) in one household. Previous trials in four households with imidacloprid-moxidectin, selamectin or injected ivermectin given once or twice a month appeared ineffective.Conclusion
D. gatoi-associated dermatitis is an emerging contagious skin disease in cats in Finland. Although pruritus is common, some cats may harbour the mites without clinical signs. In addition, due to translucency of the mites and fastidious feline grooming habits, the diagnosis may be challenging. An effective and convenient way to treat D. gatoi infestations has yet to emerge. 相似文献90.
Retrospective analysis of records, from July 1987 to June 1991, of 1140 inspections of slaughtered pigs from 154 swine herds in the Pig Health Monitoring Scheme of South Australia was conducted to evaluate patterns of variation in the prevalence and severity of skin lesions typical of sarcoptic mange. An increase in the severity of sarcoptic mange in winter and spring was observed. There was a substantial reduction in the severity of mange over the period of monitoring. These observations support the role of monitoring at slaughter in the management of endemic disease. They provide some basis for refining control programs for mange to improve cost-effectiveness. 相似文献