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141.
C. H. Bock T. T. Endalew B. K. Biswas A. K. Yadav V. Sitther M. W. Hotchkiss K. L. Stevenson B. W. Wood 《Forest Pathology》2014,44(4):266-275
Fusicladium effusum infects pecan causing yield loss, but no information is available on the genetic diversity of F. effusum. Randomly amplified polymorphic DNAs (RAPDs) and universally primed polymerase chain reaction (UP‐PCR) were compared to detect polymorphisms on a group of 20 isolates of F. effusum from 11 geographical locations in the southeastern USA. Two tests (run 1 and 2) of both the RAPD and UP‐PCRs were conducted to assess the repeatability of the methods, and the markers scored on agarose gels. In addition, the UP‐PCR markers from run 1 were scored using an automated capillary system. Both RAPDs and UP‐PCR markers detected a high level of polymorphism among the scored markers (92 and 91% of RAPD markers, and 86 and 87% of manually scored UP‐PCR markers in run 1 and 2 were polymorphic, respectively; 93% of UP‐PCR markers were polymorphic when scored using the automated system). Unweighted paired group method of arithmetic averages (UPGMA) analysis showed both RAPDs and UP‐PCR markers individually identified each isolate, producing three groupings, but only the groupings based on run 1 and 2 of the UP‐PCR contained the same isolates. Bootstrap analysis based on the Dice coefficient produced phenograms from the UP‐PCR data with weak to moderate node support (≥54) for the primary branch, but no support for the RAPDs data (≤34). A Mantel test of runs 1 and 2 using RAPDs or UP‐PCR showed good agreement (r = 0.8761 and 0.8289, p < 0.0001), but poor agreement between RAPDs and UP‐PCR. UP‐PCR results based on the interisolate Dice coefficients showed a weak to strong association with distance. Based on these results, both RAPDs and UP‐PCR markers were capable of demonstrating polymorphisms and identifying relationships among isolates of F. effusum; however, UP‐PCR markers appear to be more reliable. 相似文献
142.
Amal Kumar Biswas Jun Nozaki Michio Kurata Kenji Takii Hidemi Kumai & Manabu Seoka 《Aquaculture Research》2006,37(16):1662-1670
This study was carried out to investigate the suitability of Artemia enriched with docosahexaenoic acid (DHA) and choline as live food on the growth and survival rate of the Pacific bluefin tuna (PBT; Thunnus orientalis) larvae. The PBT larvae were fed either Artemia enriched with oleic acid (Diet 1), DHA (Diet 2), DHA+choline 1.0 mg L?1 (Diet 3) and DHA+choline 2.0 mg L?1 (Diet 4) or striped knifejaw larvae (Diet 5, reference diet), in duplicate for 12 days. Enrichment of Artemia with DHA significantly increased the DHA levels to 13.9, 13.8 and 12.5 mg g?1 on a dry matter basis in Diets 2, 3 and 4 respectively; however, the levels were significantly lower than the reference diet (26.9 mg g?1 dry matter basis; Diet 5). Although growth and survival rate were significantly improved by the enrichment of Artemia with DHA and choline, the improvement was negligible compared with the enhanced growth and survival rate of the fish larvae‐fed group (P<0.05). The results demonstrated that enriched Artemia does not seem to be the right choice to feed the PBT larvae perhaps because of the difficulties in achieving the correct balance of fatty acid with higher DHA/EPA from Artemia nauplii. 相似文献
143.
Chinmay Biswas Piyali Dey Subrata Satpathy Manoj Kumar Pratik Satya B. S. Mahapatra 《Phytoparasitica》2013,41(5):539-543
Mesta (Hibiscus sabdariffa) is an important bast fiber crop. In August 2011, there was an outbreak of a phytoplasma-like disease on H. sabdariffa in different villages of the northern coastal mesta-growing region of Andhra Pradesh, India, covering mainly two districts – Srikakulam and Vijayanagaram. The infected plants showed characteristic symptoms such as phyllody and reddening of leaves. PCR with P1/P7 universal primer pair of 16 S rDNA yielded amplicons of 1850 bp from all symptomatic mesta leaf samples similar to samples of brinjal little leaf (phytoplasma positive reference control). However, asymptomatic samples were not amplified. Multiplex nested-PCR showed simultaneous amplification of DNA fragments with phytoplasma specific primers, viz., P1/P7 universal primer pair of 16 S rDNA, nested primer pair R16F2n/R2, uvrB and DegV gene-specific uvrB-degVF/R primer generating amplicons of 1850 bp, 1200 bp and 1023bp, respectively. However, SecY-map gene specific primer SecY-mapF/R was not amplified. The 1023 bp nucleotide sequence of uvrB and DegV gene of the phytoplasma was deposited in the GenBank (NCBI) with the accession no. JX975061. NCBI BLASTn analysis of the 1023 bp products showed that the phytoplasma strain belonged to elm yellows group (16SrV-D). This is the first report that Hibiscus sabdariffa is infected by a phytoplasma and we named it mesta phyllody disease (MPD). 相似文献
144.
Summary Pashmina (cashmere) production data of Cheghu goats maintained at 2,400m altitude at the Indian Veterinary Research Institute,
Mukteswar, were analysed. The least-squares means for the first, second and third yield were 72.59±1.77g, 110.50±2.60g and
126.54±3.15g respectively. The sire effect on different yields was not significant. Year of birth was found to influence all
the three yields significantly. Seasons in different years had variable effect on yields. Difference between sex was not significant
for the first but was highly significant for the second and third yields. Intraclass regression showed that sex within age
at first combing had no effect on the first but significantly influenced the second and third yields.
Resumen Se analizaron los datos de producción de pashmina (casimir) de las cabras Cheghu mantenidas a una altitud de 2,400m en el Instituto Veterinario Indú de Investigaciones, en Mukteswar. Las medias minimas cuadradas para la primera, segunda y tercera producción fueron 72.59±1.77g, 110.50±2.60g y 126.54±3.15g, respectivamente. El efecto del progenitor sobre la producción no fue significativo. El a?o de nacimiento influenció significativamente las tres épocas de producción evaluadas. Las estaciones a través del a?o influenciaron en forma variable la producción. La diferencia entre sexo no fue significativa para la primera producción, sino si lo fue para la segunda y la tercera de una manera muy significativa. Las regresiones intraclases mostraron que el sexo dentro de la edad a la primera esquila, no tuvo efecto sobre la primera sino influenció significativamente la segunda y tercera producción.
Résumé La production de laine cashemire ou pashmine de chèvres Cheghus a été analysée par l'Institut Indien de Recherches Vétérinaires de Mukteswar situé à 2400m d'altitude. Les moyennes calculées par la méthode des moindres carrés ont donné les résultats suivants: première année, 72,59±1,77g, deuxième année 110,50±2,60g et 126,54±3,15g pour la troisième. L'influence du male sur les différents rendements n'est pas significative. L'année de naissance a en revanche influencé les trois niveaux de production. Les saisons, au cours des différentes années, ont eu un effet variable. La différence de sexe n'a pas eu d'effect sur la production de la première année alors qu'elle s'est révélée hautement significative pour les deux autres années. L'indice de régression entre classes d'age a montré que le sexe, à age égal, n'avait aucune influence sur le rendement au premier peignage alors que ceux des 2e et 3e lui étaient corrélés.相似文献
145.
146.
Biswas A Shivachandra SB Saxena MK Kumar AA Singh VP Srivastava SK 《Veterinary research communications》2004,28(4):287-298
The applicability of conventional and molecular methods for rapid detection and differentiation of Pasteurella multocida serogroup B isolates involved in an outbreak of haemorrhagic septicaemia affecting Indian buffaloes, was studied. Five isolates were obtained and were subjected to phenotypic and genotypic characterization. None of the five isolates could be differentiated on the basis of cultural, biochemical, pathogenicity and antimicrobial sensitivity patterns. Polymerase chain reaction (PCR)-based techniques were found to be specific and sensitive for rapid detection and differentiation of isolates. Repetitive extragenic palindromic (REP-) PCR, enterobacterial repetitive intergenic consensus (ERIC-) PCR and single-primer PCR differentiated all the five isolates into different profiles. All the isolates involved in the outbreak were found to have a genetic profile different from standard P. multocida strain (P52). However, three isolates had similar profiles, whereas each of the remaining two had a different profile. The study indicates the involvement of multiple strains of P. multocida in a single outbreak of haemorrhagic septicaemia in buffaloes. The results also indicate that molecular methods of detection and typing are superior to conventional methods for rapid epidemiological investigations of haemorrhagic septicaemia. 相似文献
147.
Avishek Biswas Namit Mohan Messam Raza Nasir Akbar Mir Asitbaran Mandal 《Journal of animal physiology and animal nutrition》2019,103(2):493-500
This experiment was conducted to identify the suitable replacer of broiler feed antibiotics with prebiotics (mannan oligosaccharides‐MOS or fructooligosaccharide‐FOS). Two hundred and forty (240)‐day‐old chicks were randomly divided into 30 groups (6 treatments x 5 replicates/treatment x 8 chicks/replicate). Six experimental diets T1, T2, T3, T4, T5 and T6 were formulated to contain an additional 0, antibiotic, that is, bacitracin methylene di‐salicylate (BMD) @20 mg/kg, MOS (0.1% and 0.2%) and FOS (0.1% and 0.2%) respectively. Body weight gain was significantly (p < 0.05) increased in MOS‐0.2% supplemented group at 0–21 d and 0–42 d of broiler chicken. Humoral and in vivo cell‐mediated immune response were significantly improved (p < 0.05) in BMD, MOS @0.1% or 0.2% treated group. Significant (p < 0.05) increase was recorded in total protein (except 21 d), albumin and aspartate amino transferase (AST) and decrease (p < 0.05) in alanine amino transferase (except 42 d), cholesterol and uric acid concentration. The weight of breast, thigh, back, drumstick bursa of Fabricius and thymus were higher (p < 0.05) in the birds given the MOS @0.2% (T4). It is concluded that MOS @0.2% may be suitable replacer of antibiotic growth promoter, and it has a beneficial effect on production performance, immune responses, blood biochemical parameters and cut up parts in broiler chickens. 相似文献
148.
Indrajit Bera Praveen K. Tyagi Nasir Akbar Mir Jubeda Begum Kapil Dev Pramod K. Tyagi Avishek Biswas Divya Sharma Asit Baran Mandal 《Journal of animal physiology and animal nutrition》2019,103(6):1800-1809
This study was conducted to evaluate the effects of dietary soapnut (Sapindus mukorossi) shell powder (SSP), a cheap source of saponins, on growth performance, immunity, serum biochemistry and gut health of broiler chickens. The experimental design was 4×2, employing four saponin levels (0, 100, 150 and 200 mg/kg diet), each provided for two time durations (0–42 day and 21–42 day) resulting into eight dietary treatments. Results revealed no significant effect of dietary saponins on body weight gain, feed intake and feed conversion ratio of birds. The abdominal fat percentage, heterophil to lymphocyte ratio, serum cholesterol and triglyceride levels, faecal total plate count, coliform count and E. coli count decreased (p < .05) progressively with increasing saponin levels and lower values were observed at 150 mg and 200 mg saponin levels. Significant improvement of cell‐mediated and humoral immune response was observed in birds fed 150 mg and 200 mg saponin compared to control. The serum glucose concentration was significantly (p < .05) higher in control group compared to other groups. No significant effects of dietary saponin were observed on carcass characteristics, faecal Lactobacillus count, intestinal histomorphometry and cost economics of broiler chicken production. Thus, dietary saponins at 150 mg/kg diet as SSP for three weeks (21–42 days) was optimum for better immunity and welfare of birds without adverse effects on the growth performance. 相似文献
149.
This study evaluated the physicochemical changes in the soil of potato field that was irrigated by fresh water, differentially diluted wastewater and undiluted wastewater (hereafter called wastewater). The potato crop was cultivated for consecutive three seasons under fertilized and unfertilized conditions. The wastewater contained higher concentrations of organic carbon (C), nitrogen (N), phosphorus (P), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), sulfur (S), zinc (Zn) and boron (B) and lower concentrations of heavy metals. In this study, properties of wastewater-irrigated soil were compared with fresh water-irrigated soil. The application of wastewater reduced the bulk density of the surface soil by 2.83% and augmented the porosity by 6.02%. The unsaturated hydraulic conductivity and water retention capacity of the soil were improved under wastewater irrigation. Soil pH increased due to wastewater application but decreased, to a smaller extent, due to fertilizer application. Soil EC increased both with wastewater and fertilizer application; both parameters changed significantly in the top 0–15 cm soil layer. But, at the deeper layers, they were not affected by wastewater application. The organic C, total N, available P and S of the soils increased significantly (p = 0.05) when potato field was irrigated with raw wastewater. The organic C increased by 23.80% under wastewater irrigation in the top soil layer. The N content of the soil showed similarities with the organic C contents. Exchangeable Na, K, Ca, Mg; Zn and B of the soil also increased significantly with wastewater application. So, irrigation with urban wastewater is suggested to improve soil fertility as well as to ease pressure on the fresh water in the area of water scarcity. 相似文献
150.
This research investigated the enzyme-catalyzed oxidative polymerization and precipitation/co-precipitation of the anilino compounds, p-cresidine (2-methoxy-5-methylaniline), and 4,4′-oxydianiline (ODA) suspected to be human carcinogens by the U.S. Environmental Protection Agency, as a means of treating industrial wastewater containing these pollutants. p-Cresidine is a synthetic chemical intermediate for azo dyes and pigments in the food and textile industries whereas ODA is used in the production of polyimide and poly(ester)imide resins in North America. A potentially inexpensive enzyme extracted from the soybean seed coat, soybean peroxidase (SBP), which is widely available from the agricultural commodity, was used to treat both these compounds. The optimum operating conditions such as pH, hydrogen peroxide-to-substrate concentration ratio, and the minimum SBP concentration required to achieve at least 95% SBP-catalyzed conversion of these pollutants in synthetic wastewaters were determined. Electrospray ionization mass spectrometry, employed for preliminary product determination after enzymatic conversion of the substrates, revealed the formation of azo dimers in the precipitates. A pro-forma cost analysis is presented showing the feasibility of commercialization of enzymatic treatment as an alternative, or as an adjunct, to conventional treatment methods. 相似文献