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111.
Enzyme activity and carbon dioxide evolution from upland and wetland rice soils under three agricultural practices in hilly regions 总被引:3,自引:0,他引:3
Summary Dehydrogenase activity (a measure of microbial biomass), urease activity and CO2 evolution were measured in soils planted to rice (Oryza sativa L.) under three different agricultural practices prevalent in hill regions. The effects of hill slope, terrace and valley agriculture were investigated for two cropping seasons. The valleys and terraces were kept flooded during each cropping season while the hill slopes were cultivated with dryland practices. The type of agricultural practice and the date of observation had a significant influence on enzyme activity and CO2 evolution. A positive correlation was observed between dehydrogenase and urease activity and soil moisture content. Dehydrogenase and urease activity and soil respiration were positively correlated among themselves. The activity of both enzymes and CO2 evolution were highest in valley soils followed by terrace and hill-slope sites. 相似文献
112.
D. Sharma R. C. Sharma R. Dhakal N. B. Dhami D. B. Gurung R. B. Katuwal K. B. Koirala R. C. Prasad S. N. Sah S. R. Upadhyay T. P. Tiwari G. Ortiz-Ferrara 《Euphytica》2008,164(3):689-698
The national maize improvement program in Nepal regularly receives elite maize (Zea mays L.) genotypes from CIMMYT and other countries and tests them for their performance stability in highly diverse environments.
Studies were conducted on research stations and farmers’ fields at five sites in three years to determine performance stability
of exotic maize genotypes. Replicated on-station and on-farm studies were conducted using 25 and 10 genotypes, respectively,
including a local check and an improved check (Manakamana-3), in 2004–2006. We analyzed grain yield, days to flowering, plant
and ear height, plant population, husk cover, and plant and ear aspect. Stability and genotype superiority for grain yield
was determined using genotype and genotype × environment (GGE) biplot analysis that compares among a set of genotypes with
a reference ‘ideal’ genotype, which has the highest average value of all genotypes and is absolutely stable. Several genotypes
produced significantly higher grain yield than the local check. Four genotypes (‘Across9942 × Across9944’, ‘Open Ended White
Hill Population’, ‘Population 44C10’ and ‘ZM621’), that produced significantly higher grain yield than the improved check,
also had other agronomic traits (days to flowering, plant and ear height, number of ears, resistance to leaf blight, plant
and ear aspect and husk cover tightness) equal to or better than the improved check. GGE-biplot analysis showed that Across9942 × Across9944
and ZM621 were the most superior genotypes in the on-station and on-farm trials, respectively. The findings from this study
provide new information on the stability of the maize genotypes that are also adapted to other regions of the world. Such
information could be useful for maize improvement program for the highlands in Nepal and other similar environments. 相似文献
113.
Julia Pinedo-Gil Ana Tomás-Vidal Daniel Rico-Barges Brijesh K. Tiwari Carlos Álvarez García Miguel Jover-Cerdá 《Journal Of Aquatic Food Product Technology》2019,28(1):38-48
The present study compares a control diet to four experimental diets, in which two red beet (14% and 28%) and two betaine levels (0.9% and 1.63%) were incorporated in rainbow trout diets according to a factorial design. The effects of the inclusion of different red beet and betaine concentrations on fatty acid (FA) profile, lipid peroxidation, and antioxidant activity on rainbow trout fillets were investigated. Although no significant differences were observed with the control group, results indicated that red beet and betaine improved fish fillet FA profile, producing an increase in polyunsaturated FAs, mainly docosahexaenoic acid. Higher red beet and betaine concentrations increased flavonoid and phenolic content in the diets; however, no effects were observed for the antioxidant properties of rainbow trout fillets. 相似文献
114.
T.K. Behera S.S. Dey A.D. Munshi Ambika B. Gaikwad Anand Pal Iqbal Singh 《Scientia Horticulturae》2009,120(1):130-133
Gynoecism has been used on a large scale in heterosis breeding of cucumber. Production of hybrid seeds in bitter gourd is highly expensive because it is done mainly through hand pollination. But utilization of a gynoecious line would be more economical and easier method. Since gynoecious parent has only female flowers, the open pollinated seeds it produces will be F1 hybrid. It will reduce the cost of male flower pinching and hand pollination. Two gynoecious lines, DBGY-201 and DBGY-202 were crossed with two monoecious cultivars, “Pusa Do Mausami” and “Pusa Vishesh” and their F2 populations were observed to determine the inheritance pattern of gynoecious sex form. Another experiment was conducted to determine magnitude of heterosis by utilizing nine inbred lines including one gynoecious line, DBGY-201 in diallel (without reciprocal) mating system. All the gynoecious hybrids showed significant heterosis in a desirable direction for traits like sex ratio (male:female), days to first picking, number of fruits per plant, yield per plant, and vine length. The segregation pattern in F2 suggested that gynoecious sex form in bitter gourd was governed by single recessive gene. The gynoecious hybrids DBGY-201 × “Pusa Vishesh” and DBGY-201 × “Pusa Do Mausami” were important for early harvest (~50 days after sowing) whereas DBGY-201 × “Priya” and DBGY-201 × “Arka Harit” were promising for higher yield. 相似文献
115.
Brucellosis not only represents an important health restraint on livestock but also causes high economic losses in many developing countries worldwide. Despite considerable efforts made for the control of brucellosis, the disease is still spreading in many regions (such as the Middle East) where it represents one of the most important health hazards impacting both animals and humans. The present review aims to investigate the efficacy of veterinary control programs regarding brucellosis, with a special focus on current prevention, control, and eradication approaches. The reasons for unsuccessful control programs such as the absence of highly effective vaccines and non-certified bulls are also debated, to understand why the prevalence of brucellosis in livestock is not decreasing in many areas despite considerable efforts taken to date. The importance of governmental and regional investment in brucellosis control remains one of the main limiting factors owing to the limited budget allocated to tackle this disease. In this context, one health concept has generated novel comprehensive approaches with multiple economic implications across the livestock industry and public health. However, the implementation of such global preventive strategies appears to be a key issue for many endemic and low-income countries. According to the collected data, epidemiological contexts including management and trade systems along with well-defined agro-ecological zones should be evaluated in brucellosis endemic countries to improve milk production and to enhance the sustainability of the livestock sector at both national and regional levels. 相似文献
116.
Tiwari J Kumar S Kolte AP Swarnkar CP Singh D Pathak KM 《Veterinary parasitology》2006,138(3-4):301-307
Benzimidazole (BZ) resistance in Haemonchus contortus is linked primarily with the mutation in the beta-tubulin isotype 1 gene that substitute phenylalanine (Phe) to tyrosine (Tyr) at 200 codon of the gene. In the present study, a new restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) technique has been developed for detection of BZ resistance in the beta-tubulin isotype 1 gene of H. contortus. The technique utilizes two primers viz. AvikaF and AvikaR to amplify the region containing mutation in the beta-tubulin gene followed by restriction digestion. After digestion, the 'rr' individuals (homozygous resistant) revealed 257 and 48 bp bands, the 'rS' individuals (heterozygous) showed 305, 257 and 48 bp bands, while 'SS' individuals (homozygous susceptible) revealed uncut 305 bp band. A total of 162 adult male H. contortus collected from Avikanagar, Jaipur and Bikaner regions (54 from each region) were genotyped for analyzing BZ resistance in the beta-tubulin gene. Out of which, 130 adults were 'rr' types, 20 'rS' types and 12 'SS' types. The results showed that genotypic frequencies of different genotypes (rr, rS and SS) were highly significant difference among the three regions (P<0.001). The 'rr' individuals were higher (98%) in Jaipur followed by Avikanagar (93%) and Bikaner (50%) regions. Overall, the prevalence of BZ resistant allele (r) was higher (86%) as compared to BZ susceptible allele (S) (14%). The technique was also found suitable for genotyping of larvae of H. contortus and yielded reproducible results. The study indicated that RFLP-PCR is an easy, reproducible and less expensive than allele specific PCR. This technique will be helpful in establishing the prevalence rate of BZ resistance in H. contortus and can also be utilized for existing worm control programme. 相似文献
117.
Bangar Pooja Tyagi Neetu Tiwari Bhavana Kumar Sanjay Barman Paramananda Kumari Ratna Gaikwad Ambika Bhat K. V. Chaudhury Ashok 《Journal of Crop Science and Biotechnology》2021,24(2):153-165
Journal of Crop Science and Biotechnology - Mungbean [Vigna radiata (L.) R. Wilczek var. radiata] is vital grain legume having nutritional and socio-economic importance, especially in the... 相似文献
118.
119.
Dimri U Singh SK Sharma MC Behera SK Kumar D Tiwari P 《Research in veterinary science》2012,93(1):296-299
The present study was aimed to examine lipid peroxides, antioxidants, zinc, copper, iron panels and apoptosis in peripheral blood of dogs with clinical dirofilariosis. In comparison to healthy control, erythrocytic lipid peroxides level and superoxide dismutase activity were significantly (P<0.01) higher in diseased dogs. However, level of reduced glutathione and activities of glutathione peroxidase, glutathione-S-transferase and catalase were significantly (P<0.01) lower in diseased dogs. Blood zinc, copper and iron levels in dogs with dirofilariosis were significantly (P<0.01) lower than the healthy control. The percent apoptotic peripheral leukocytes were significantly higher in dogs with dirofilariosis in comparison with healthy control. From the present study, it is concluded that significant alterations in oxidant/antioxidant balance, mineral status and rate of apoptosis in peripheral blood may be implicated in the pathogenesis of clinical canine dirofilariosis. 相似文献
120.
Kuldeep Dhama Vasudevan Gowthaman Kumaragurubaran Karthik Ruchi Tiwari Swati Sachan M. Asok Kumar 《The Veterinary quarterly》2017,37(1):31-42
Haemorrhagic enteritis virus (HEV), an adenovirus associated with acute haemorrhagic gastro-intestinal disease of 6–11-week old turkeys predominantly hampers both humoral and cellular immunity. Affected birds are more prone to secondary complications (e.g. colibacillosis and clostridiosis) and failure to mount an effective vaccine-induced immune response. HEV belongs to the new genus Siadenovirus. Feco-oral transmission is the main route of entry of the virus and it mainly colonizes bursa, intestine and spleen. Both naturally occurring virulent and avirulent strains of HEVs are serologically indistinguishable. Recent findings revealed that ORF1, E3 and fib genes are the key factors affecting virulence. The adoption of suitable diagnostic tools, proper vaccination and biosecurity measures have restrained the occurrence of disease epidemics. For diagnostic purposes, the best source of HEV is either intestinal contents or samples from spleen. For rapid detection highly sensitive and specific tests such as quantitative real-time PCR based on Taq man probe has been designed. Avirulent strains of HEV or MSDV can be effectively used as live vaccines. Novel vaccines include recombinant hexon protein-based subunit vaccines or recombinant virus-vectored vaccines using fowl poxvirus (FPV) expressing the native hexon of HEV. Notably, subunit vaccines and recombinant virus vectored vaccines altogether offer high protection against challenge or field viruses. Herein, we converse a comprehensive analysis of the HEV genetics, disease pathobiology, advancements in diagnosis and vaccination along with appropriate prevention and control strategies. 相似文献