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21.
Optimum conditions for the contact sensitivity (CS) test using 2,4-dinitrochlorobenzene (DNCB) were sensitization with 0.25 ml of a DNCB solution (10 mg/ml) and challenge with one-tenth of this dose two weeks later. This produced reaction in terms of skin thickness which could be easily observed and measured. The cutaneous hypersensitivity developed slowly, reaching its maximum manifestation after 24 h of challenge and gradually declining thereafter. The development of a skin reaction was typical of delayed type hypersensitivity and was characterized histopathologically by congestion, oedema, mononuclear and heterophilic cell infiltration in the dermal layer and lymphocytic perivascular cuffing. The efficiency of the CS test was compared with that of the lymphocyte transformation (LT) test and graft-versus-host (GvH) reaction for monitoring cell-mediated immunity (CMI) in normal and CMI deficient chickens. CMI deficient chickens were prepared by neonatal thymectomy and inoculation of antithymocyte serum. The CMI response of deficient chickens was significantly less (p less than 0.01) as determined by all three tests. The percentage decrease in response to mount GvH, CS and LT was 88.9, 58.3 and 74.6, respectively. All the tests were found to be equally effective in assessing CMI response in chickens as determined by comparing the means of their performances.  相似文献   
22.
A study was undertaken to investigate the role of in ovo administrated carbohydrates on the expression pattern of growth and immune‐related genes. In ovo injections (n = 400) were carried out on the 14th day of incubation into the yolk sac/amnion of the broiler chicken embryos. Expression of growth‐related genes: chicken growth hormone (cGH), insulin‐like growth factor‐I & II (IGF‐I & II) and mucin were studied in hepatic and jejunum tissues of late‐term embryo and early post‐hatch chicks. Expression of candidate immune genes: Interleukin‐2, 6, 10 and 12 (IL‐2, IL‐6, IL‐10 and IL‐12), Tumour necrosis factor‐alpha (TNF‐α) and Interferon gamma (IFN‐γ) were studied in peripheral blood monocyte cells of in ovo‐injected and control birds following antigenic stimulation with sheep RBC (SRBC) or mitogen concanavalin A (Con‐A). Glucose injection significantly increased the expression of IGF‐II gene during embryonic period and both cGH and IGF‐II in early post‐hatch period, while ribose‐injected chicks had higher expression of IGF‐II gene during embryonic stage. Enhanced mucin gene expression was also observed in fructose‐injected chicks during embryonic age. Glucose‐injected chicks had higher expression of IL‐6 or IL‐10, while those injected with fructose or ribose had higher expression of IL‐2, IL‐12 and IFN gamma. It is concluded that in ovo supplementation of carbohydrates might help in improving the growth of late‐term embryos and chicks. In ovo glucose could modulate humoral‐related immunity, while fructose or ribose might help in improving the cellular immunity in broiler chickens.  相似文献   
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The most important evolutionary event in the success of commercial tea cultivation outside China in ~30 countries came about by the origin of India hybrid tea in India, derived from the extensive spontaneous hybridization that took place between the Assam type tea growing in the forest regions of Assam, North-East India and China type tea introduced from China in ~1875 to many regions of North-East India. The release of an enormous pool of vigorous and highly variable plants of India hybrid tea in North-East India was a significant step forward for the origin and evolution of tea as a highly successful crop plant. The 1,644 accessions and clones of India hybrid tea, representatives of known 15 morphotypes, were screened by 412 AFLP markers amplified by 7 AFLP primer pair combinations. All the 412 genetic loci were polymorphic across the 1,644 accessions and clones. The analysis was done with distance (PCoA and NJ) methods, and the STRUCTURE (Bayesian) model. Both PCoA and NJ analysis clustered 1,644 tea accessions and clones into six major groups with one group in each, constituted mostly by China hybrid, Assam China hybrid and Assam hybrid morphotypes, of distinct genetic identity. No group was exclusive for any particular morphotype. The accessions and clones belonging to morphotypes, Assam type, Assam hybrid, China hybrid and China Cambod were distributed in all the groups. It is the Assam type/Assam hybrid morphotypes which exhibit much broader genetic variability than in China type/China hybrid/Cambod type/Cambod hybrid morphotypes. The STRUCTURE analysis inferred 16 populations (K = 16), for which the greatest values of probability were obtained. Nine of the 16 clusters were constituted by the tea accessions and clones of ‘pure’ ancestry. The remaining clusters were of ‘mixed’ ancestry. This analysis provides evidence that the accessions and clones of the same morphotype are not always of same genetic ancestry structure. The tea accessions and clones obtained from outside North-East India shared the same groups (distance method) and clusters (STRUCTURE model) which were constituted by North-East India accessions. The present study also demonstrates very narrow genetic diversity in the commercial tea clones vis-à-vis the profound genetic diversity existing in the tea accessions. These clones were distributed in hardly two of the six groups in NJ tree. The identified 105 core accessions and clones, capturing 98% diversity, have their origin from almost all groups/subgroups of NJ tree.  相似文献   
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Optimum conditions for haemolytic complement (HC) assay in buffalo serum were standardized. In all, 11 indicator systems of red blood cells (RBC) and haemolysins were investigated. Maximum HC CH50 titre was obtained with rabbit RBC sensitized with goat haemolysin. The effect of pH, Ca2+ and Mg2+ concentration, ionic strength, time and temperature were studied. Of all the variables, ionic strength influenced the HC activity most significantly. The standard system for titrating the HC consisted of rabbit RBC sensitized with goat haemolysin, sucrose-veronal buffer with pH 7.5, ionic strength 0.023 M and Ca2+ and Mg2+ concentrations 6 x 10(-4) and 2 x 10(-3) M, respectively. Incubation at 37 degrees C for 2 h gave highest haemolytic activity. With this protocol 5-7-fold higher HC activity was recorded than with prestandardized conditions. Levels of HC were determined in the sera of 98 buffaloes aged from 1 month to 12 years. The lowest mean CH50 units of 401 +/- 0.35 per ml were recorded in buffalo calves below 3 months of age. The mean HC levels increased with age, reaching peak values of 2349 +/- 62.25 CH50 units/ml in 2-3-year-old buffalo. Animals in the age group 5-12 years had significantly decreased (P less than 0.05) mean HC levels of 1545 +/- 68.94.  相似文献   
27.
Aegilops umbellulata acc. 3732, an excellent source of resistance to major wheat diseases, was used for transferring leaf rust and stripe rust resistance to cultivated wheat. An amphiploid between Ae. umbellulata acc. 3732 and Triticum durum cv. WH890 was crossed with cv. Chinese Spring Ph I to induce homoeologous pairing between Ae. umbellulata and wheat chromosomes. The F1 was crossed to the susceptible Triticum aestivum cv. ‘WL711’ and leaf rust and stripe rust resistant plants were selected among the backcross progenies. Homozygous lines were selected and screened against six Puccinia triticina and four Puccinia striiformis f. sp. tritici pathotypes at the seedling stage and a mixture of prevalent pathotypes of both rust pathogens at the adult plant stage. Genomic in situ hybridization in some of the selected introgression lines detected two lines with complete Ae. umbellulata chromosomes. Depending on the rust reactions and allelism tests, the introgression lines could be classified into two groups, comprising of lines with seedling leaf rust resistance gene Lr9 and with new seedling leaf rust and stripe rust resistance genes. Inheritance studies detected an additional adult plant leaf rust resistance gene in one of the introgression lines. A minimum of three putatively new genes—two for leaf rust resistance (LrU1 and LrU2) and one for stripe rust resistance (YrU1) have been introgressed into wheat from Ae. umbellulata. Two lines with no apparent linkage drag have been identified. These lines could serve as sources of resistance to leaf rust and stripe rust in breeding programs.  相似文献   
28.
The infectivity rate of Babesia equi in the salivary glands of Hyalomma anatolicum anatolicum was assessed. The hungry nymphs were fed on a donkey experimentally infected with B. equi. The engorged dropped-off nymphs were collected at different levels of parasitaemia and kept in BOD incubator. After ecdysis, the hungry adults were prefed on rabbits for different time intervals, thereafter the salivary glands were dissected out and acini were examined after methyl green pyronin (MGP) staining. A total of 134 male and 139 female ticks were dissected out. Average infected acini per tick were found to be significantly higher (p<0.05) in male as compared to the female ticks. Further, maximum infected acini in both male and female ticks were found at 24h of prefeeding on rabbits and overall infected acini per tick increased with rise in parasitaemia. The release of infected ticks on susceptible donkeys resulted in development of clinical babesiosis.  相似文献   
29.
Halichondrin B is a complex, natural, polyether macrolide derived from marine sponges. Eribulin is a structurally-simplified, synthetic, macrocyclic ketone analogue of Halichondrin B. Eribulin was approved by United States Food and Drug Administration in 2010 as a third-line therapy for metastatic breast cancer patients who have previously been treated with an anthracycline and a taxane. It has a unique microtubule dynamics inhibitory action. Phase III studies have either been completed or are currently ongoing in breast cancer, soft tissue sarcoma, and non-small cell lung cancer. Phase I and II studies in multiple cancers and various combinations are currently ongoing. This article reviews the available information on eribulin with respect to its clinical pharmacology, pharmacokinetics, pharmacodynamics, mechanism of action, metabolism, preclinical studies, and with special focus on clinical trials.  相似文献   
30.
An experimental work leading to the development of economical and improved stilling basin designs for circular pipe outlet in comparison to Garde's stilling basin [Garde, R.J. & Saraf, P.D., Journal of Irrigation and Power 1986, 145–154], is reported in this paper. In the present study, attempts are made to develop efficient and shorter stilling basin models keeping the basin floor at the invert level of the pipe outlet for inflow Froude number Fr = 5.50. The new designs are arrived at by conducting a systematic experiments on the stilling basin models having appurtenances like a wedge-shaped splitter block, a modified grid, an intermediate sill and a rounded step. Scour index, a non-dimensional number has been defined to compare the performance of the stilling basin models using the same erodible material and time of experimental run. The performance of the newly developed stilling basin models has been compared with that of Garde's stilling basin model G-D. The proposed model M is also compared with the earlier stilling basin model M-12, as suggested by Goel & Verma [Journal of Irrigation and Drainage Systems 15(1), 2001, 81–91].  相似文献   
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