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51.
On the diffusion constant of water in wheat 总被引:1,自引:0,他引:1
Diffusion-weighted magnetic resonance imaging (MRI) was used to obtain diffusion constants for water in the embryo and endosperm of wheat. Our experiments showed a significant difference between the diffusion constant for the two components. It was also shown that water diffusion in both the endosperm and embryo deviates from the typically observed Gaussian behavior in bulk fluids, showing a time-dependent diffusion constant. Diffusion constants for the embryo and endosperm were shown to differ by an order of magnitude. Using a model for restricted diffusion, information on the endosperm pore size and the embryo cell dimensions could be obtained. 相似文献
52.
Samit Kumar Nandi Biswanath Kundu Samir Kumar Ghosh Dipak Kumar De Debabrata Basu 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(2):183-191
The present study was undertaken to evaluate porous hydroxyapatite (HAp), the powder of which was prepared by a novel aqueous solution combustion technique, as a bone substitute in healing bone defects in vivo, as assessed by radiologic and histopathologic methods, oxytetracycline labeling, and angiogenic features in Bengal goat. Bone defects were created in the diaphysis of the radius and either not filled (group I) or filled with a HAp strut (group II). The radiologic study in group II showed the presence of unabsorbed implants which acted as a scaffold for new bone growth across the defect, and the quality of healing of the bone defect was almost indistinguishable from the control group, in which the defect was more or less similar, although the newly formed bony tissue was more organized when HAp was used. Histologic methods showed complete normal ossification with development of Haversian canals and well-defined osteoblasts at the periphery in group II, whereas the control group had moderate fibro-collagenization and an adequate amount of marrow material, fat cells, and blood vessels. An oxytetracycline labeling study showed moderate activity of new bone formation with crossing-over of new bone trabeculae along with the presence of resorption cavities in group II, whereas in the control group, the process of new bone formation was active from both ends and the defect site appeared as a homogenous non-fluoroscent area. Angiograms of the animals in the control group showed uniform angiogenesis in the defect site with establishment of trans-transplant angiogenesis, whereas in group II there was complete trans-transplant shunting of blood vessel communication. Porous HAp ceramic prepared by an aqueous combustion technique promoted bone formation over the defect, confirming their biologic osteoconductive property. 相似文献
53.
Datta Apurba Kumar Haider Mohammed Ziaul Ghosh Sumon Kumar 《Tropical animal health and production》2019,51(1):55-64
Tropical Animal Health and Production - A study was conducted to analyze the dairy farming sector of Bangladesh from an economic viewpoint. Primary data was collected from smallholder dairy farms... 相似文献
54.
Molecular expression of caprine estrogen receptor gene 1 in reproductive and non‐reproductive tissues 下载免费PDF全文
S Saraswat PK Rout SD Kharche SK Jindal AK Goel 《Reproduction in domestic animals》2016,51(6):1049-1054
During the last decades, physiological effects of oestrogens have been increasingly explored by scientists and biotechnologists. Estrogens exert a wide range of effects on a large variety of cell types. Oestrogen and its receptors are essential for sexual development and reproduction. Estrogen receptor alpha is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene estrogen receptor gene 1 (ESR1), responsible for better fertility. The ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. Therefore, this is a good startby to study the expression pattern of estrogen receptor 1 gene in high‐fertile (G1) and low‐fertile (G2) bucks of Jamunapari and Barbari breeds identified on the basis of seminal quality traits and fertility trials. RNA was extracted from the tissues by TRIzol method. The identification and expression pattern of caprine ESR1 gene was analysed by real‐time PCR (Roche LC‐480). Our work shows that the relative quantification by RT‐PCR indicates more fold in head of epididymis as compared to spleen of caprine ESR1 gene. Furthermore, the RT‐PCR indicated that fertile bucks of Jamunapari breed have more fold value as compared to Barbari breed in respect of reproductive organ. 相似文献
55.
Effects of low‐density lipoproteins as additive on quality parameters and oxidative stress following cryopreservation of mithun (Bos frontalis) spermatozoa 下载免费PDF全文
P Perumal SK Srivastava SK Ghosh KK Baruah S Bag JS Rajoria K Kumar C Rajkhowa M Pande N Srivastava 《Reproduction in domestic animals》2016,51(5):708-716
Artificial breeding of mithun poses several challenges including lack of standard protocol for cryopreservation of spermatozoa. This is further complicated by harmful effects of hen's egg yolk (EY) as additive in extender. Purified low‐density lipoproteins (LDL) extracted from EY have been shown as beneficial over EY extender for long‐term semen storage in several species. This investigation explored use of LDL versus EY on semen quality and oxidative stress following freezing–thawing of spermatozoa. A total of 25 of 50 ejaculates based on biophysical parameters were selected for the experiment. After diluting with the Tris‐citrate‐glycerol (TCG) extender, each sample was split into three equal aliquots: Group I, control, EY; Group II and Group III contained 8% and 10% purified LDL, respectively. Frozen–thawed samples were evaluated for motility parameters (progressive, and in the bovine cervical mucus penetration test [BCMPT]), viability, sperm and nuclear abnormality, acrosome integrity, and enzymatic (leakage of intracellular contents) and biochemical (oxidative stress) profiles and in vitro fertility (IVF) assay. Study revealed a significant (p < .05) improvement in viability, sperm and nuclear abnormality, acrosome integrity, motility (progressive and in cervical mucus), cholesterol content, and reduction in the leakage of intracellular enzymes in Group II. Moreover, intactness of acrosome and biochemical membranes was protected significantly (p < .05) in addition to significant (p < .05) improvement in binding per cent and binding index in IVF assay in extender containing 8% LDL. These results demonstrate that although cryopreservation of mithun's spermatozoa in EY was comparable with other species, addition of 8% LDL holds a clear advantage over EY or 10% LDL. 相似文献
56.
57.
Probiotic efficiency of Bacillus sp. in Labeo rohita challenged by Aeromonas hydrophila: assessment of stress profile,haemato‐biochemical parameters and immune responses 下载免费PDF全文
Ankita Nandi Goutam Banerjee Suhas Kumar Dan Koushik Ghosh Arun Kumar Ray 《Aquaculture Research》2017,48(8):4334-4345
Fish are always susceptible to a wide variety of deadly pathogens which cause a huge loss in aquaculture industries. In this investigation, we have demonstrated the in vivo probiotic efficiency of Bacillus sp. MVF1 (GenBank Acc. No. KP256503) in Labeo rohita challenged with pathogenic strain of Aeromonas hydrophila (MTCC 1739). To check the probiotic potential of the selected bacterial strain, fish were divided into four groups: control, D1, D2 and D3. A total of 100 days (70 days probiotic feeding + 71th day sampling and 28 days challenged test + 29th day sampling) of feeding trial was conducted. To establish the probiotic potential of Bacillus sp. MVF1, certain haematological parameters (haemoglobin, total erythrocyte and leucocyte count), serum biochemical parameters (total protein, albumin and globulin), immune parameters (serum lysozyme and total IgM levels) and hepatic stress profile (malondialdehyde production, superoxide dismutase and catalase activity) have been measured. Our results demonstrated that red blood cell number, white blood cell number and haemoglobin content were much higher in D2 group fish compared to other groups and control fish. Similarly, total protein contents, albumin concentration, globulin concentration, lysozyme activity and IgM production were also recorded to be highest in D2 group fish. This finding clearly indicated the probiotic potential of Bacillus sp. MVF1 in L. rohita. Furthermore, our results also demonstrated that 1 × 107 CFU g?1 feed (D2) provides better immunity compared to 1 × 105 (D1) and 1 × 109 (D3). Due to beneficial effects, the bacterium Bacillus sp. MVF1 might be useful in aquaculture industries to reduce the disease susceptibility. 相似文献
58.
Effect of irrigation and nitrogen application methods on input use efficiency of wheat under limited water supply in a Vertisol of Central India 总被引:1,自引:0,他引:1
K. K. Bandyopadhyay A. K. Misra P. K. Ghosh K. M. Hati K. G. Mandal M. Moahnty 《Irrigation Science》2010,28(4):285-299
Field experiments were conducted in a deep Vertisol at the Indian Institute of Soil Science, Bhopal during the years 2001–2005
to assess the effect of five different irrigation strategies through combinations of sprinkler and flood irrigation and two
N application methods on yield and water use efficiency of wheat (cv WH 147). The amount of irrigation applied each year differed
according to the availability of water in the water harvesting pond to simulate the actual water crisis faced by the farmers
in this region during these years due to monsoon failure. Results indicated that when wheat was grown only with 8-cm irrigation
at sowing or 14 cm up to the crown root initiation stage, dry sowing of wheat immediately followed by sprinkler and subsequent
irrigation through flooding produced the highest yield and water and nitrogen use efficiencies. However, when 20-cm irrigation
was supplied up to the flowering stage or 14-cm irrigation was supplied up to tillering stage through sprinkler in 4 and 3
splits, respectively, at critical growth stages, maximized the grain yield and water and nitrogen use efficiencies. Across
the years, the crop yield and water and nitrogen use efficiencies increased with increase in water supply. 相似文献
59.
A highly sensitive,non‐invasive qPCR‐based strategy for direct quantification of Yersinia ruckeri in fish faeces 下载免费PDF全文
Bikramjit Ghosh Philip B. B. Crosbie Barbara F. Nowak Andrew R. Bridle 《Journal of fish diseases》2018,41(9):1421-1428
Finfish with asymptomatic Yersinia ruckeri infections pose a major risk as they can transmit the pathogen and cause clinical outbreaks in stock populations. Current tools have insufficient quantitative ability for accurately detecting the trace levels of Y. ruckeri typically associated with asymptomatic infection, necessitate invasive or lethal sampling, or require long processing times. This study presents a highly sensitive qPCR‐based method, targeting part of the Y. ruckeri 16S rRNA sequence, that is capable of detecting extremely low levels of Y. ruckeri in noninvasively collected faecal samples. Quantitative precision and accuracy of faecal sample analysis was consistent, despite the complexity of the faecal matrix. The assay demonstrated linearity over a six log‐wide dynamic range. Its limit of detection (LOD) and limit of quantification (LOQ) were 4 and 10 copies of the target sequence, respectively. Sensitivity of the assay was comparable to other qPCR‐based methods without requiring invasive or lethal sampling. Applicability as a screening strategy was tested using passively collected faecal samples. Asymptomatic Y. ruckeri infection was detected in all samples, although none of the fish exhibited overt infection. This method will be beneficial for finfish disease management if developed further as a noninvasive, screening tool against asymptomatic Y. ruckeri infection. 相似文献
60.