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71.
Oral squamous cell carcinoma (OSCC) is an aggressive and treatment‐resistant malignancy in both feline and human patients. Recent work has demonstrated aberrant expression of fatty acid synthase (FASN) and an increased capacity for lipogenesis in human OSCC and other cancers. In human OSCC, inhibition of FASN decreased cell viability and growth in vitro, and diminished tumour growth and metastasis in murine preclinical models. This study aimed to characterize FASN as a therapeutic target in feline OSCC. Immunohistochemistry revealed high FASN expression in primary feline OSCC tumours, and FASN expression was detected in OSCC cell lines (3 feline and 3 human) by immunoblotting and quantitative real‐time‐polymerase chain reaction (qRT‐PCR). Orlistat, a FASN inhibitor, substantially reduced cell viability in both feline and human OSCC lines, although feline cell lines consistently displayed higher sensitivity to the drug. FASN mRNA expression among cell lines mirrored sensitivity to orlistat, with feline cell lines expressing higher levels of FASN. Consistent with this observation, diminished sensitivity to orlistat treatment and decreased FASN mRNA expression were observed in feline OSCC cells following incubation under hypoxic conditions. Treatment with orlistat did not potentiate sensitivity to carboplatin in the cell lines investigated; instead, combinations of the 2 drugs resulted in additive to antagonistic effects. Our results suggest that FASN inhibition is a viable therapeutic target for feline OSCC. Furthermore, cats may serve as a spontaneous large animal model for human oral cancer, although differences in the regulation of lipogenesis between these 2 species require further investigation.  相似文献   
72.
The restoration of native forbs in the Great Basin and similar dryland ecosystems remains a great challenge for land managers. Variable soil water, precocious germination and emergence, and the presence of soil fungal pathogens often reduce plant establishment. Novel restoration treatments that increase soil water during early forb life stages, delay germination and emergence to coincide with favorable spring conditions, and reduce mortality from soil fungal pathogens may benefit native forb restoration. We compared the efficacy of three novel treatments—snow fencing, plant protection fabric, and seed coatings—to improve establishment of a forb species native to the Great Basin, basalt milkvetch (Astragalus filipes Torr. ex A. Gray). We replicated treatments plus a no-treatment control at three sites in the Great Basin in a randomized complete block design over 2 yr. To evaluate the efficacy of our restoration treatments, we measured germination, seedling emergence, establishment, and second-yr survival. The effects of snow fencing and plant protection fabric varied by site and life stage and were likely influenced by the wet spring conditions across sites, particularly the two northern sites. Snow fencing increased establishment and second-yr survival at one site. Plant protection fabric did not benefit any life stage at any site. Seed coatings increased seedling emergence at all sites but did not affect establishment or survival. Overall, second-yr survival remained low across all sites and treatments. Our study indicates that our treatments can positively affect basalt milkvetch emergence, establishment, and survival, but additional management actions are needed to improve long-term restoration success of native forbs.  相似文献   
73.
The role of melatonin as a protective neurohormone against restoring cyclicity in summer anoestrous animals in photoperiod species has gained wider acceptance. This study was designed to uncover the evidence the slow‐release melatonin (MLT) has on initiation of ovarian cyclicity and conception rate (CR) in summer anoestrous buffaloes. Thus, buffaloes diagnosed as summer anoestrous (absence of overt signs of oestrus, concurrent rectal examination and radioimmunoassay for serum progesterone at 10 days interval) were grouped as untreated (Group I, sterilized corn oil, n = 8) and treated (Group II, single subcutaneous injection of MLT @18 mg/50 kg bwt in sterilized corn oil, n = 20). Animals treated and detected in oestrus were artificially inseminated (AI) followed by division into Group III (second dose of MLT on 5th day post‐AI, n = 8) and Group IV (no melatonin administration, n = 10). Blood samples were collected at 4 days interval for estimation of serum MLT, progesterone and oestrogen using radioimmunoassay kit. Mean oestrous induction rate (OIR), oestrous induction interval (OII), interoestrous interval (IOI) and CR were estimated. Compared to control, concentration of melatonin was significantly (p < 0.05) higher in treated group ranging from 14.34 ± 1.72 to 412.31 ± 14.47 pg/ml whereas other two hormones did not show any concentration difference. Melatonin‐administered buffaloes showed significantly (p < 0.05) higher (90%) OIR with OII of 18.06 ± 1.57 days. Results showed improvement in conception rate in buffaloes administered with post‐insemination melatonin. It can be concluded from the study that slow‐release melatonin supplementation restored cyclicity in summer anoestrous animals resulting in improvement in conception rate in buffaloes.  相似文献   
74.
Hydraulic conductivity at compacted minimum bulk density value was reported earlier to be a sensitive and significant index of soil structure (1,2,3). The compacted bulk density value is minimum only for a critical moisture condition of the soil and the value varies slightly with the type of soil used. When once this critical value is determined for a soil type, the expedient routine use of this technique depends mostly on the method for obtaining soil samples with the critical moisture content.  相似文献   
75.
In humans, regulatory T (T reg) cells are known to play a critical role in both the regulation of immune homoeostasis and the progression of cancer. However, there is little information about the identification, characterization and the function of T reg cells in canine tumours. We identified T reg cells in 28 canine seminoma samples using a Forkhead box P3 (Foxp3) antibody and investigated the relationship between T reg cell infiltration and histopathological features of classical and spermatocytic seminomas (SE and SS, respectively). The Foxp3 protein showed nuclear immunostaining in infiltrating lymphocytes, and Foxp3+ cells were diffused or focally distributed in seminoma tissues. Foxp3+ cells were frequently present in the SS histotype, in seminomas that showed no evidence of tumour cell invasion into the vessels and in seminomas showing a diffuse growth pattern with three cell types. Neither the SE/SS histotype nor the histopathological features of the tumour correlated with Foxp3+ cell counts. These results indicate that Foxp3+ T reg cells may be associated with a less malignant histological phenotype or may not play a critical role in the immune response of canine seminomas. Moreover, Foxp3+ T reg cells may be associated with SS seminoma, but further studies, involving a larger number of samples, are required to better understand whether these cells play a critical role in the immune response in canine seminomas. This is the first report to demonstrate the characteristics of T reg cell infiltration in canine seminoma.  相似文献   
76.
Anti-nutritional factors of developing seeds and pod walls of fenugreek were evaluated which affect their nutritional value. Sucrose, raffinose and stachyose decreased with maturity of seeds in all the cultivars. Total, non-reducing sugars increased and reducing sugars decreased at maturity in all the cultivars. The reducing sugars decreased with maturity of pod walls. The flatus producing sugars were maximum in PEB pod walls. Saponin content increased towards maturity of seeds but decreased at maturity of seeds and decreased at maturity in pod walls of all cultivars. Phytate increased with seed maturity up to 95 days after anthesis, while phytate decreased in pod walls of all the cultivars with maturity. Total phenol, catechol and flavonol decreased with advancement of pod wall development. Total phenol decreased except HM 46 a maturity of seeds.  相似文献   
77.
Buffaloes are known for their productivity as compared to average yielding cows due to higher fat percentage, better feed conversion ability and disease resistance. On the other hand, the reproductive performances of buffaloes are often considered as poor owing to late sexual maturity, weak/silent oestrus, repeat breeder and prolonged intercalving interval. The study of cascade of events during oestrus and oestrous cycle can be useful for the improvement of reproductive efficiency of buffaloes. More precisely, the hormonal changes initiated at the molecular level within the animal determine the reproductive nature of the species. Nucleotide/protein sequence analysis serves as a vital tool in analysing the binding of the hormones for their effect or functions. In this study, we have reported cloning and characterization of the complete coding (cDNA) sequence of oxytocin receptor gene (OXTR) in buffaloes. Buffalo OXTR gene contains an uninterrupted ORF of 1176 nucleotides corresponding to an inferred polypeptide length of 391 amino acids (aa). The molecular weight of the deduced aa sequence was found to be 43 kDa with an isoelectric point of 9.253 and 16.328 charge at pH 7.0. The deduced protein sequence consists of 38 strongly basic (+) (K,R), 22 strongly acidic (?) (D,E), 186 hydrophobic (A, I, L, F, W, V) and 95 Polar (N, C, Q, S, T, Y) aa. Results indicated that aspartate (D) at aa position 85 and D, R and C at aa positions 136, 137 and 138, respectively, are conserved in buffaloes. The buffalo OXTR gene shared a per cent similarity ranging from 84.7 to 98.1 and 88.5 to 97.7 at nucleotide and deduced aa sequence levels, respectively, with that of other species. Phylogram constructed on the basis of either nucleotide or deduced aa sequences of buffalo OXTR gene showed that buffalo, cattle and sheep have diverged from human and swine and formed a separate clad. The buffalo sequence has shown maximum similarity and closeness with cattle followed by sheep both at nucleotide and at aa level.  相似文献   
78.
Interferon‐τ (IFN‐τ) has been recognized as the primary embryonic signal responsible for maternal recognition of pregnancy. Uterine endometrium produces both prostaglandin F2α (PGF2α) and prostaglandin E2 (PGE2). PGF2α is responsible for the luteolysis; however, PGE2 favours establishment of pregnancy by its luteoprotective action. In this study, the dose‐response effect of recombinant bovine IFN‐τ (rbIFN‐τ) on prostaglandin (PG) production by buffalo endometrial stromal cells cultured in vitro was studied. Buffalo endometrial stromal cells were isolated by double enzymatic digestion, initially with trypsin III followed by a cocktail of trypsin III, collagenase type II and DNase I and subsequently cultured till confluence. Further, cells were treated with different doses of rbIFN‐τ (0.001, 0.01, 0.1, 1.0 and 10 μg/ml) and keeping a separate set of control. Culture supernatant was collected after 6, 12 and 24 h of treatment. PG levels in the culture supernatant were measured by enzyme immune assay (EIA) and total cellular protein estimated by Bradford method. Results indicated that buffalo endometrial stromal cells following rbIFN‐τ treatment enhanced the secretion of both PGE2 and PGF2α, and also its ratio in a strict dose‐dependent manner with a significant increase (p < 0.01) in PGE2 production at 1 μg/ml dose of rbIFN‐τ and maximal stimulation for both PG was observed at 10 μg/ml. Further, both PG production and its ratio were increased significantly (p < 0.01) in a time‐dependent fashion in all the groups at 6, 12 and 24 h post‐treatment with highest level achieved at 24 h as compared with control. Absolute levels of PGE2 remained higher than PGF2α indicating PGE2 as the major PG produced by endometrial stromal cells. The dose‐dependent response of rbIFN‐τ signifies the importance of optimum concentration of IFN‐τ for the embryonic development especially during the critical period to establish successful pregnancy.  相似文献   
79.
In the present investigation, soils representing ten locations and three agro-climatic zones of foot-hills of north-west Himalayas were studied to assess Non-exchangeable Potassium (NEK) reserves, its release and influence of K-fixing capacity and clay minerals on NEK release. Maximum release of non-exchangeable K was obtained in temperate zone soils (295 mg kg− 1) followed by intermediate zone (227 mg kg− 1) and sub-tropical zone soils (106 mg kg− 1), having relative soil quality index (RSQI) values of 85, 80 and 65, respectively. The quantitative analysis of clay minerals, through XRD technique, revealed that the temperate soils have more illite (averaging 62%) which holds well as a reason for high NEK reserves of 1556 mg kg− 1 in these soils in comparison to intermediate (having illite averaging 53%) and sub-tropical (having illite averaging to 49%) soils having NEK amounting to 1022 and 918 mg kg− 1, respectively. In order to study the NEK removal from the soils under investigation, maize was grown as a test crop and potassium was applied through four treatments having four levels of K (0, 15, 30 and 60 mg kg− 1) applied as KCl. The crop demonstrated significant response in terms of dry matter yield up to 30 mg kg− 1 in sub-tropical and intermediate soils while no such response was obtained in temperate soils. The percent NEK removed by maize crop from NEK reserves was 14, 25 and 20% in sub-tropical, intermediate and temperate soils, respectively. The information about NEK release, its removal as well as its relationship with K fixing capacity, clay minerals and RSQI can be used for understanding the K buffering potential of soils especially under adverse soil and climatic conditions that prevail in southwest India. Besides, the regression equations developed can be used for predicting NEK release on the basis of K fixing capacity and clay mineralogical composition.  相似文献   
80.
Summary Four, out of the maximum of 5 possible, primary trisomics have been identified karyomorphologically. These are Pseudo Normal, Slender, Semi Erect and Weak, trisomic for C, A, B and D chromosomes respectively. The trisomics are reasonably distinguishable from one another on the basis of qualitative and quantitative characters, like growth habit and rate, stem thickness, internode length, size and shape of leaves and flowers and fertility. The most common type of association at meiosis is 5II+1 I followed by 1 III+4 II. The trisomics differ in the number and type of trivalents. There is a significant increase in range and number of ring bivalents in all trisomics particularly in Slender. This is attributable to a correspondingly significant increase in chiasma frequency. The reasons for this are not clear. Anaphase segregation is ordinarily normal and pollen fertility is high except in Semi Erect in which it is correlated with segregational errors. Although, seed setting is apparently normal in all except Slender, yet germinability is very poor. Greater phenotypic effects and lesser tolerance to the addition results in trisomics for the long submedian and satellited A and medium submedian D chromosomes than for B and C chromosomes.  相似文献   
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