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61.
Bikas C. Debnath Purnendu Biswas Barun Roy 《Journal of animal physiology and animal nutrition》2019,103(1):29-40
Three hundred thirty‐day‐old unsexed commercial broiler chicks (Vencobb‐400) with initial average body weight of 44.04 ± 0.42 g were allocated into five experimental groups, in a completely randomized design (CRD) with 21‐day experiment. Groups were formed according to dose of supplemental L‐threonine in various rations i.e., 100% NRC specification, 100% threonine of Vencobb‐400 strain specification, 110% threonine of Vencobb‐400 strain specification, 120% of threonine of Vencobb‐400 strain specification and 130% threonine of Vencobb‐400 strain specification. Average daily feed intake (ADFI), average daily body weight gain (ADG), cumulative feed conversion ratio (CFCR), carcass characteristics, immune response, intestinal morphometry and biochemical profile were studied. The ADFI and ADG increased linearly and quadratically as dietary threonine levels were increased. However, the CFCR did not differ (p ? 0.05) among the groups. Though the carcass weight and drumstick yield did not differ (p ? 0.05) among the groups, the relative breast yield increased linearly (p = 0.007). The relative dressing yield and relative thigh weight increased linearly (p = 0.05 and p = 0.03, respectively). The relative weight of immune organs like bursa and thymus increased linearly. The mean total serum immunoglobulin, ND‐ELISA titre and the mean lymphocyte proliferation response index increased linearly, whereas mean phagocytic activity index of neutrophil increased linearly (p < 0.001) and quadratically (p = 0.001). The mean villus height (VH), crypt depth (CD), villus surface area and mean goblet cell number/villus increased linearly and quadratically, whereas the villus width (VW) and goblet cell density increased quadratically. The serum glucose increased linearly (p = 0.001), whereas serum total protein concentration and serum globulin level increased both linearly and quadratically. The albumin: globulin ratio tended to decrease linearly. There was a significant decrease (p < 0.05) in serum cholesterol and VLDL cholesterol level. However, a linear increment (p = 0.04) in the blood serum HDL cholesterol level with a linear reduction (p = 0.01) in the blood serum LDL cholesterol was noticed. 相似文献
62.
In India, a single soil loss tolerance ( T ) value of 11.2 Mg/ha is by default used for formulating land restoration strategies for all soil types, climates and vegetation covers. However, this single 'T' value does not represent a true picture of soil loss tolerance under all land uses. The objective of our study was to develop adjusted ' T ' values for Central India using soil infiltration rate, bulk density, total organic carbon, erodibility and soil pH. Soil state was defined using a quantitative model involving different soil functions which were used to convert soil parameters to a 0 to 1 scale. The normalized values were then multiplied by appropriate weighing factors based on relative importance and sensitivity analysis of each indicator. Based on overall assessment, each soil mapping unit was categorized into soil groups I, II or III. A general guideline of USDA – Natural Resource Conservation Service (USDA-NRCS) was followed to calculate soil loss tolerance for each soil group using effective soil depth. Adjusted ' T ' values for Central India ranged from 2.5 to 12.5 Mg/ha compared with a default value of 11.2 Mg/ha. Use of these values for soil mapping units will improve conservation planning and assist with planning the development of sustainable agriculture. 相似文献
63.
Bahram Falahatkar Samaneh Poursaeid Iraj Efatpanah Bahman Meknatkhah Amal Biswas 《Journal of the World Aquaculture Society》2012,43(5):679-687
The effect of five different light regimes on growth, stress and hematological indices was studied in Persian sturgeon, Acipenser persicus. Fish with average weight of 645.3 ± 11.2 g were subjected to different photoperiods (24 L, 12 L:12 D, 16 L:8 D, 8 L:16 D and 24 D) for 8 wk. Blood samples were collected at the end of the experiment for measuring cortisol, glucose and hematological features. The whole growth parameters showed no significant difference. Plasma cortisol concentration was significantly higher in 12 L:12 D, while the lowest level was observed in fish exposed to 24 D. No significant changes were observed among the treatments for glucose concentration. Lactate concentration varied significantly among the treatments. Some hematological indices including hematocrit and number of white blood cells were affected by different light regimes, but the others (hemoglobin and number of red blood cells) were not affected significantly. The results showed that photoperiod manipulation can alters some stress‐related metabolites and may enhance growth rate in fish exposing to continuous darkness. 相似文献
64.
Mohammad Shaheed Hossain Chowdhury Shampa Biswas Md. Abdul Halim S. M. Sirajul Haque Nur Muhammed Masao Koike 《林业研究》2007,18(1):27-30
Status of organic carbon (C), total nitrogen (N), available potassium (K), calcium (Ca) and phosphorus (P) in three different depths (0-5 cm, 5-15 cm and 15-30 cm) on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill. Tracts (CHTs) were evaluated and compared with those in degraded bush forests, through digging three profiles in each land use. The content of all the five nutrients was found to be higher in the soil of orange orchard than in the soil of forest. But the variation was not consistent for both the slopes. The content varied depth wise also, having the highest value in surface soil in case of both the land uses on both the slopes. A mean available K content was significantly higher in orange orchard than in forest on 55% slope, while it was lower on 35% slope. Surface soil contained the nutrients of K and Ca with the amount of 0.2905-mg·g^-1 soil and 3.025-mg·g^-1 soil respectively in the orchard, while 0.1934-mg·g^-1 soil and 1.6083-mg·g^-1 soil were respectively in the forest. Organic carbon and total nitrogen were found more or less similar in surface soil on both the land uses showing a slight difference. Available P was found only in orange orchard, and in forest it was too little in amount to detect by the spectrophotometer. The degraded forests were poor in nutrient content due to high rate of soil erosion, which would be possible to be improved by bringing it under tree cover as proved by the adaptation of orange orchard there. 相似文献
65.
Dhar P Chattopadhya K Bhattacharyya D Biswas A Roy B Ghosh S 《Journal of agricultural and food chemistry》2007,55(14):5875-5880
Sesame lignans are working as antioxidants in various physiological functions. In the present study, the antioxidative effect of sesame lignans is examined in chemically induced diabetes mellitus (DM) in rats against lipid profile and lipid peroxidations. DM was induced in four groups of rats by injection of alloxan. The control groups (non-diabetic and diabetic) received a diet containing sunflower oil while the rest of the three experimental diabetic groups received a diet containing 0.25% alpha-tocopherol (D-Toc), 0.5% sesame lignan (D-SL), and 0.25% alpha-tocopherol+0.25% sesame lignan (D-Toc-SL) in sunflower oil for 4 weeks. Lipid profile and lipid peroxidations of plasma, erythrocyte membrane (EM), and liver tissues were measured. The total cholesterol, non-HDL cholesterol, plasma lipid peroxidation, and also LDL-peroxidation decreased, and HDL cholesterol increased significantly (P<0.05) in all the experimental groups as compared to the control diabetic sunflower oil group. The triacylglycerol (TAG) level in plasma decreased significantly in the D-SL and D-Toc-SL groups as compared to control diabetic group. Significant decrease in TAG level was observed in the D-SL group as compared to the D-Toc group. LDL peroxidation also decreased significantly in the D-Toc-SL group as compared to the D-Toc group. EM lipid peroxidation and liver lipid peroxidation decreased significantly in the D-Toc, D-SL, and D-Toc-SL groups as compared to the control diabetic group. Liver TAG level decreased more significantly in the D-SL and D-Toc-SL groups than in the control diabetic group. So, sesame lignans at 0.5% level and sesame lignan + alpha-tocopherol significantly ameliorate the alteration in lipid profile and the adverse free radical generative influence of DM induced by alloxan. 相似文献
66.
Biswas S Sanyal A Hemadri D Tosh C Mohapatra JK Manoj Kumar R Bandyopadhyay SK 《Veterinary microbiology》2006,116(1-3):187-193
A total of 18 foot-and-mouth disease virus (FMDV) serotype Asia1 field isolates belonging to two different lineages (including the divergent group) as delineated earlier in VP1-based phylogeny were sequenced in the non-structural 3A and 3C protein-coding regions. The phylogenetic trees representing the regions coding for the non-structural proteins were very similar to that of the structural VP1 protein-coding region. Phylogenetic comparison at 3C region revealed clustering of Asia1 viruses with the isolates of serotypes O, A and C in the previously identified clade. Comparison of amino acid sequences identified lineage-specific signature residues in both the non-structural proteins. Overall analysis of the amino acid substitutions revealed that the 3A coding region was more prone to amino acid alterations than 3C region. 相似文献
67.
Saxena MK Singh VP Kumar AA Chaudhuri P Singh VP Shivachandra SB Biswas A Sharma B 《Veterinary research communications》2006,30(8):851-861
Repetitive extragenic palindromic sequence-based PCR (REP-PCR) was used to characterize 67 field isolates of Pasteurella multocida originating from different animal species and geographical regions of India. REP-PCR was found to be rapid and reproducible
(three repeats were done). These isolates yielded different 23 profiles which were clustered into eight groups. The discrimination
index was moderate (D value 0.83). Somatic and antigenic typing of the isolates did not reveal any correlation with REP-PCR profiles. There was
no host-specific, type-specific, region-specific or pathenogenicity-specific pattern. The REP profiles of isolates obtained
from wild animals were similar to those obtained from domestic animals. Two common bands were present in all the isolates
irrespective of somatic or antigenic types. The results were not comparable with earlier findings, which had shown high discrimination
index and correlation with disease presentation.
Saxena, M.K., Singh, V.P., Kumar, A.A., Chaudhuri, P., Singh, V.P., Shivachandra, S.B., Biswas, A. and Sharma, B., 2006. REP–PCR
analysis of Pasteurella multocida isolates from wild and domestic animals in India. Veterinary Research Communications, 30(8), 851–861 相似文献
68.
The metacommunity concept provides a spatial perspective on community dynamics, and the landscape provides the physical template
for a metacommunity. Several aspects of landscape heterogeneity, such as landscape diversity and composition, and characteristics
of the matrix between habitat patches such as habitat connectivity, and geometry of habitat patches, may moderate metacommunity
processes. These aspects of landscape heterogeneity are rarely considered explicitly in the metacommunity discussion, however.
We propose landscape contrast (i.e., the average dissimilarity in habitat quality between neighboring patches) as a key dimension
of landscape heterogeneity. The concept of landscape contrast unifies discrete and continuous landscape representations (homogeneous,
gradient, mosaic and binary) and offers a means to integrate landscape heterogeneity in the metacommunity concept. Landscape
contrast as perceived by the organisms affects several fundamental metacommunity processes and may thus constrain which metacommunity
models may be observed. In a review of empirical metacommunity studies (n = 123), only 22 % of studies were explicit about their underlying landscape model assumptions, with striking differences
among taxonomic groups. The assumed landscape model constrained, but did not determine, metacommunity models. Integration
and explicit investigation of landscape contrast effects in metacommunity studies are likely to advance ecological theory
and facilitate its application to real-world conservation problems. 相似文献
69.
Ligation of the caudal mesenteric artery during resection and anastomosis of the colorectal junction for annular adenocarcinoma in two dogs 总被引:1,自引:1,他引:0
An 8-year-old terrier cross and a 10-year-old German Shorthaired Pointer presented to the University Veterinary Centre, Sydney, for investigation of long-standing tenesmus and dyschezia. Both patients had an annular adenocarcinoma at the colorectal junction. Exploratory laparotomy was performed and the affected large intestinal segment was removed by resection and anastomosis. In both dogs, the caudal mesenteric artery was intimately associated with the mass, necessitating its ligation and transection. Postoperatively, there was no evidence of anastomosis breakdown in either case and both animals recovered well from surgery. The dogs were euthanased 8 and 10 months, respectively, after surgery because of clinical signs relating to metastatic disease. 相似文献
70.