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91.
AK Ghosh D Sarkar DC Nayak P Bhattacharyya 《Archives of Agronomy and Soil Science》2013,59(6):583-591
A sequential fractionation scheme, based on a soil phosphorous fractionation, was developed to assess the chemical nature, and thus the potential bioavailability and mobility of As, at the sites. Soil As was separated into five fractions with (i) anion exchange resin, (ii) NaHCO3, (iii) NaOH, (iv) HCl, (v) residual. Most sites contained relatively low concentrations of As in the two most labile fractions. The bulk of the contaminant As at the sites seemed to be associated with soil amorphous Fe and Al minerals and the dominant clay minerals which help in As sorption are montmorillonite and mica. Resin-extractable As in particular might provide a good index of potential As bioavailability and mobility. 相似文献
92.
Uttam Kumar Sarkar Prashant Kumar Deepak Dhurendra Kapoor Raje Singh Negi Samir Kumar Paul & Sreeprakash Singh 《Aquaculture Research》2005,36(10):941-945
Induced breeding of climbing perch, Anabas testudineus was conducted by synthetic hormone Wova‐FH in the intensity level of 0.1, 0.2 and 0.3 mL kg?1 of body weight respectively. The brooders were injected one time and left to spawn in the spawning hapa in the sex ratio between male and female as 2:1. It was found that at all the intensity level hormone Wova‐FH could enhance the fishes to breed and lay eggs whereas no breeding was observed in control set. The spawning time, quantity of the brooder spawn, fertilization rate, hatching rate and survival rate were quantified in each set of experiment. The egg output/female was significantly higher in 0.3 mL in comparison with 0.1 and 0.2 mL kg?1 of body weight. The statistical analysis showed significant (P≤0.05) effect between hormone dose on fertilization rate, egg output and hatching rate. The present experiment suggests that Wova‐FH at the dose of 0.3 mL kg?1 body weight of fish is more effective which might be considered for raising captive population. 相似文献
93.
U.K. Sarkar W.S. Lakra P.K. Deepak R.S. Negi S.K. Paul A. Srivastava 《Aquaculture (Amsterdam, Netherlands)》2006,261(1):141-150
This is the first report on the successful larval rearing of captive bred population of Chitala chitala (Hamilton). C. chitala is one of the endangered fresh water fish species in India for which the development of controlled larval rearing procedures are needed for stock enhancement. Fifteen days old post-hatchlings were stocked for 28 d in a 30 L recirculatory tanks using eight different diets i.e. live feed (tubifex worms, chironomous larvae, zooplanktons,), dry feed (dry tubifex, spirulina, daphnia) and other non-conventional feed (fish eggs and boiled egg-yolk). Fishes accepted all types of diets. The study revealed that specific growth rate (SGR) was higher in post-hatchlings fed on live tubifex worms (2.40 ± 0.72) followed by fish eggs (2.15 ± 0.71), dry tubifex (2.12 ± 0.40), chironomous larvae (1.91 ± 0.44), spirulina (1.79 ± 0.38), daphnia (1.42 ± 0.79) and planktons (1.37 ± 0.77) whereas minimum SGR was recorded with boiled egg-yolk (0.63 ± 0.5). A highly significant difference (p < 0.01) in SGR was observed in fish fed on live feed (tubifex worms, chironomous larvae, planktons, spirulina), dry tubifex and fish eggs whereas for daphnia and boiled egg-yolk it was only significant (p < 0.05). The final mean weight and weight gain showed highly significant difference (p < 0.01) in live tubifex, zooplanktons, spirulina, chironomous larvae, dry tubifex and fish eggs, whereas daphnia and boiled egg-yolk fed larvae showed significant difference (p < 0.05). Highest mean survival rate on day 28 was observed in live tubifex worms (94%) and chironomous larvae (92%). The post-hatchlings reared with spirulina and daphnia showed same survival rate of 88% whereas the lowest mean survival of 66% was recorded in boiled egg-yolk. The experiments showed that captive bred post-hatchlings of C.chitala could be reared in experimental recirculatory system for attaining higher growth and survival during early life stages. However, methods to improve the larval rearing have to be improved further for commercial farming of the species. 相似文献
94.
施氮对香稻某些生理效应的研究 总被引:8,自引:0,他引:8
用1个非和时稻品种Ratna和3个香稻品种HKR228,Basmati370及CBⅡ施氮和不施氮处理对比试验结果,施氮可使稻株光合作用,呼吸作用,植株含氮量提高。但是,施氮对光合作用的促进作用未达差异显著水平。对比非香稻品种Ratna和春稻品种HKR228,施氮对叶片呼吸作用促进作用前者大于后者。 相似文献
95.
Summary Greenhouse experiments demonstrated a differential interaction between potato viruses X and Y in two potato cultivars. Enhancement
of PVX synthesis in doubly infected plants occurred only in the PVY-susceptible potato cv. Ulla, whereas PVX multiplication
was almost completely inhibited in the doubly infected PVY-resistant cv. Franzi. However, a synergistic effect was also evident
in the latter cultivar in the form of a growth inhibition of the plants. An increased multiplication of one or both of the
viruses is, therefore, not related to a synergistic reaction. 相似文献
96.
VS Chouhan RP Panda VP Yadav V Babitha FA Khan GK Das M Gupta SS Dangi G Singh S Bag GT Sharma B Berisha D Schams M Sarkar 《Reproduction in domestic animals》2013,48(5):810-818
The aim of this study was to document the expression and localization of VEGF system comprising of VEGF isoforms (VEGF 120, VEGF 164 and VEGF 188) and their receptors (VEGFR1 and VEGFR2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors. In general, all the components of VEGF system (the VEGF isoforms and their receptors) were found in the water buffalo CL during the oestrous cycle. The mRNA as well as protein expression of VEGF system was highest during the early and mid‐luteal phase, which later steadily decreased (p < 0.05) after day 10 to reach the lowest level in regressed CL. As demonstrated by immunohistochemistry, VEGF protein was localized predominantly in luteal cells; however, VEGFR1 and VEGFR2 were localized in luteal cells as well as in endothelial cells. In conclusion, the dynamics of expression and localization of VEGF system in buffalo corpora lutea during the luteal phase were demonstrated in this study, indicating the possible role of VEGF system in the regulation of luteal angiogenesis and proliferation of luteal as well as endothelial cells through their non‐angiogenic function. 相似文献
97.
M Pande GK Das FA Khan M Sarkar JK Prasad MC Pathak H Kumar 《Reproduction in domestic animals》2013,48(1):79-84
The effect of uterine infection on size and follicular fluid composition of the largest follicle was studied in buffalo. Reproductive tracts were collected from 102 graded Murrah buffaloes at an abattoir. Uterine infection was diagnosed by physical examination of uterine mucus, white side test and uterine cytology. Samples with pus‐containing mucus, positive reaction on white side test and/or >5% neutrophils were considered to be positive for uterine infection. Diameter of the largest follicle was measured, and follicular fluid was aspirated and assayed for nitric oxide (NO), ascorbic acid (AA), cholesterol, oestradiol (E2) and progesterone (P4). Infected buffaloes had smaller‐sized (p < 0.0001) largest follicles than non‐infected buffaloes. Follicular fluid collected from the largest follicle in infected buffaloes had greater (p < 0.0001) NO and P4 concentrations coincident with lesser AA (p < 0.001), cholesterol (p < 0.0001) and E2 (p < 0.0001) concentrations. Results indicated that uterine infection has an inhibitory effect on growth of the largest follicle in buffalo. The changes in follicular fluid composition in infected buffaloes suggest that the direct effect of uterine infection on ovarian function may be mediated through an alteration in the follicular microenvironment. Greater NO and lesser AA concentrations in the follicular fluid of infected animals are novel findings. 相似文献
98.
I. Hyder K. RameshS. Sharma S. UniyalV.P. Yadav R.P. PandaV.P. Maurya G. SinghM. Sarkar 《Livestock Science》2013,152(1):63-73
This study aims to assess the effect of different energy levels of restriction on physiological and genetic level adaptability. Eighteen adult nonpregnant does (average BW 33.56 kg) were used in the present study. The ewes were divided into three groups, viz., GI (n=6; control), GII (n=6; 30% feed intake of control), GIII (n=6; 40% feed intake of control). The study was conducted for 40 days covering a period of two estrous cycles. Blood samples were collected every ten days interval. The parameters studied were allometric parameters (viz., body weight, and body condition) scoring and physiological responses (viz., respiration rate, pulse rate, and rectal temperature) biochemical parameters (glucose, albumin, creatinine, cholesterol), hormones (T3, T4, cortisol, leptin) and mRNA expression profile of leptin in peripheral blood mononuclear cells (PBMC). The nutritional stress significantly (P<0.05) affected most of the parameters. There was a significant (P<0.05) reduction in Body weight, Body condition score and. The physiological responses were significantly (P<0.05) affected. Among the biochemical parameters mean serum glucose first increased significantly (P<0.05) and then stabilized in GII whereas as there was no change in serum glucose levels in GIII. Serum albumin significantly (P<0.05) affected in late stages of study. There was no significant (P<0.05) changes in serum creatinine. Among hormonal parameters there was significant decrease in T3 in both the groups; T4 increased significantly in GII on 10th day and then stabilized whereas no changes was observed in GIII. Cortisol levels increased significantly (P<0.05) in both GII and GIII. There was a significant (P<0.05) reduction in serum leptin levels in GII but in GIII significant reduction was observed only 10th and 30th day of study. The mRNA expression was significantly (P<0.05) upregulated in GII on 30th day followed by a significant downregulation whereas in GIII significant (P<0.05) downregulation was only seen on 30th and 40th days. It can be concluded from our study that animals can maintain near physiological homeostasis even at 40% energy intake levels. The animals have innate physiological ability to survive periods of nutritional stress by adjusting leptin levels which are required for maintaining the physiological normalcy. 相似文献
99.
Soumen Chattopadhyay Kabiul Akhter Ali S. Gandhi Doss Nirvan K. Das Ramesh K. Aggarwal Tapas K. Bandopadhyay A. Sarkar A. K. Bajpai 《Journal of General Plant Pathology》2010,76(2):87-93
Powdery mildew caused by the ascomycete Phyllactinia guttata (syn. P. corylea) is a major foliar disease worldwide of the unique mulberry (Morus spp.) for silkworm feed. Genetic resistance to powdery mildew, the most sustainable and economical strategy for disease control,
is still elusive for tropical mulberry. About 147 germplasm sources, representing 18 countries of origin, were screened for
resistance to P. guttata in six seasonal fields and greenhouse trials after exposure to natural and artificial inoculum, respectively. In the field,
the level of plant responsiveness to disease was assessed from 30 to 62 days after pruning in each season as variations in
the disease severity index (DSI), disease incidence (DI%) and area under the disease progress curve (AUDPC). These measures
differed significantly among the germplasm. Of 147 germplasm sources, ~6.8% had useful resistance (two high and nine moderately
resistant) to the powdery mildew pathogen on the basis of DSI. The AUDPC values were 13.5-fold higher in the most susceptible
accession—(Philippines) than the least responsive (Vietnam-2). The results of DSI were strongly correlated with the obtained
DI values (r = 0.92; P < 0.01) and AUDPC (r = 0.89; P < 0.01). Moreover, field screening results were highly correlated (R
2 = 0.839) with values from the greenhouse evaluation using artificial inoculum. However, the DSI values in field and greenhouse
screenings for three sources (Non-nayapati, Nao-khurkul and Tista Valley) varied significantly. A relatively low disease reaction
of 09 resources (Vietnam-2, Ankara and 07 others) using different assessment scales after natural and artificial inoculation
prove, for the first time, that they have potential in breeding for resistance in tropical mulberry to powdery mildew. 相似文献
100.
Two (di)haploids (2n = 2x = 24) and nine tetraploids (2n = 4x = 48) obtained from Solanum tuberosum through anther culture were characterized for nDNA variation, phenotypic variation and nuclear microsatellite polymorphism.
Androgenic (di)haploids were also characterized for late blight resistance. The (di)haploid C-13 was derived from Indian tetraploid
potato cv. Kufri Chipsona-2, while D4 from TPS (true potato seed) parental line JTH/C-107, which is an interspecific hybrid
between Indian tetraploid cv. Kufri Jyoti and diploid (2n = 2x = 24) cultivated species S. phureja Juz. & Buk. IVP-35. C-13 and D4 (both male-fertile) could be distinguished from their corresponding tetraploid anther donors
based on plant height, shoot number, terminal leaflet length and width, leaf ratio, anther length, pollen diameter and corolla
width and radius. A complete reversal of flower color occurred in D4, and C-13 was highly resistant to late blight. Most interestingly,
about 3–7% increase in nDNA content occurred in most of the anther-derived tetraploids. Both the androgenic (di)haploids and
their anther donors had unique genotypes at the microsatellite loci POTM1-2, STM0015 and STM0019b. However, the nine anther-derived tetraploids shared the same allelic profiles with their anther donor JTH/C-107 at all the
microsatellite loci, except at STM0019a where they were characterized by the absence of a standard donor allele (186-bp). A typical (di)haploid-specific allele was
detected for the locus STWAX-2 where the standard donor alleles were replaced by a 230-bp allele in both C-13 and D4. The over-expression of microsatellite
variation in D4 that also shows triallelic profiles at the microsatellite loci POTM1-2 and STM0015 can perhaps be attributed to its chimeric structure, which might have been formed through incomplete fusion of two different
pro-embryos during the first steps of microspore division. 相似文献