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161.
This is the fourth Capsule review article provided by the WSAVA Global Pain Council and which discusses the use of ice or cold therapy as a non-pharmacologic modality for pain control in small animal practice. The physiological effects of cold therapy on tissues, receptors and ion channels are discussed; as well as indications, recommendations for, and limitations of use.  相似文献   
162.
This study investigated the effect of type‐I interferon (IFN) on the expression of matrix metalloproteinases (MMPs) of the bovine endometrial stromal cells (BES) and epithelial cells (BEE). The cells were separated and purified from the caruncles and cultured in DMEM/F‐12 containing 10% fetal bovine serum. Spheroids were generated by using ascorbate. Zymograms of the supernatant showed that BEE predominantly expressed MMP‐9, whereas MMP‐2 was expressed in BES and homo‐spheroids. While MMPs expression was not detected in hetero‐spheroids. Real‐time quantitative PCR revealed that type‐I IFN and P4 suppressed the gene expression of MMP‐2 and MMP‐9 in hetero‐spheroids, respectively. On the other hand, gelatin zymography analysis of the supernatant showed that type‐I IFN strongly promote the clearance of MMPs. While zymograms of the MMPs stocked in the hetero‐spheroids were significantly reduced by type‐I IFN. Phenylmethanesulfonyl fluoride and leupeptin (both are serine proteinase inhibitors) significantly repressed the clearance of MMP‐2 and MMP‐9 induced by type‐I IFN. Moreover, collagen fibers in hetero‐spheroids significantly decreased after the treatment with type‐I IFN. In conclusion, it was suggested that type‐I IFN participate in the tissue remodeling by regulation the clearance of MMPs.  相似文献   
163.
Cardiovascular effects of tramadol were evaluated in dogs anesthetized with sevoflurane. Six beagle dogs were anesthetized twice at 7 days interval. The minimum alveolar concentration (MAC) of sevoflurane was earlier determined in each dog. The dogs were then anesthetized with sevoflurane at 1.3 times of predetermined individual MAC and cardiovascular parameters were evaluated before (baseline) and after an intravenous injection of tramadol (4 mg/kg). The administration of tramadol produced a transient and mild increase in arterial blood pressure (ABP) (P=0.004) with prolonged increase in systemic vascular resistance (SVR) (P<0.0001). Compared with baseline value, mean ABP increased significantly at 5 min (119% of baseline value, P=0.003), 10 min (113%, P=0.027), and 15 min (111%, P=0.022). SVR also increased significantly at 5 min (128%, P<0.0001), 10 min (121%, P=0.026), 30 min (114%, P=0.025), 45 min (113%, P=0.025) and 60 min (112%, P=0.048). Plasma concentrations of tramadol were weakly correlated with the percentage changes in mean ABP (r=0.642, P<0.0001) and SVR (r=0.646, P<0.0001). There was no significant change in heart rate, cardiac output, cardiac index, stroke volume, pulmonary arterial pressure, right atrial pressure and pulmonary capillary wedge pressure. In conclusion, the administration of tramadol produces a prolonged peripheral vascular constriction in dogs anesthetized with sevoflurane, which is accompanied with a transient and mild increase in arterial blood pressure. It also indicated that the degree of vasoconstriction might depend on the plasma concentration of tramadol.  相似文献   
164.
Branched oligosaccharide phosphate (BOS-P) and oleyl BOS-P (OA-BOS-P) were prepared from potato starch with a high phosphate content by limited amylolysis with α-amylase and exhaustive digestion with glucoamylase and oleylation of BOS-P through a lipase-catalyzed solid-phase synthesis. The multifunctional properties of OA-BOS-P were evaluated in terms of surface tension, emulsifying ability, Ca(2+)-binding ability, and ability to control the gelatinization and retrogradation of potato starch. OA-BOS-P exhibited better emulsifying ability than BOS-P and Ca(2+)-binding ability similar to that of BOS-P. OA-BOS-P elevated the gelatinization temperature and reduced viscosity more than BOS-P. OA-BOS-P also reduced retrogradation as indicated by the reduction in the setback viscosity, turbidity, development of the ordered structure and crystalline structure, and digestibility, whereas BOS-P elevated the setback and turbidness, despite reducing the development of the crystalline structure, except for development of the ordered structure, similar to that of the control. These results show that OA-BOS-P could be a useful material with novel emulsifying, Ca(2+)-binding, and starchy food-controlling properties.  相似文献   
165.
The regulation of plasma membrane ATPase activity by salt stress was investigated in barley roots. The plasma membrane fractions were prepared from the roots treated with or without 200 mM sodium chloride (NaCl) for one day. After salt treatment, ATPase activity reduced by 20 to 30% as compared with that of control roots. No significant changes in the content of total phospholipid and sterol were detected in the plasma membrane fraction by salt stress. After extraction of most of the phospholipids in the plasma membrane vesicles with a solution containing 1% (W/V) octylglucoside and 1% (W/V) Triton X‐100, the ATPase activity in salt‐stressed roots was lower than that of control roots. After reconstitution of detergent‐extracted protein into liposome, the reduction of ATPase activity by salt stress did not recover. Based on immunoblott analysis, the relative amount of H+‐ATPase in plasma membrane fraction prepared, from NaCl‐stressed roots was smaller than that of control roots. These results indicate that the reduction of H+‐ATPase activity by salt stress was caused by the decrease in the amount of H+‐ATPase rather than the modification of ATPase.  相似文献   
166.
Abstract

Potassium (K) in microbial cells, microbial biomass K, in soil has been recently recognized as a K pool for plant growth. We determined soil microbial biomass K in paddy fields to reveal its importance as a K pool in paddy field soil for the first time. Microbial biomass K ranged from 5 to 21 mg K kg?1 in the soil samples periodically collected from a paddy field and the value corresponded to 41% of the exchangeable K on average. Both microbial biomass K and exchangeable K increased conspicuously due to the long-term application of livestock manure compost or rice straw compost. Biomass K was higher than exchangeable K under K-deficient conditions in the long-term experimental plots without K application. The present study revealed that the microbial biomass contained considerable amounts of K in paddy field soil, indicating the need for evaluation of the microbial biomass K as a source and a stock of K in soil that has been overlooked.  相似文献   
167.
Stress-induced apoptosis in larval embryos of Japanese flounder   总被引:1,自引:0,他引:1  
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168.
Pituitary gonadotropins (GTHs) are of primary importance in triggering oocyte growth and maturation. However, the actions of GTHs are not direct, but are mediated by the ovarian production of steroidal mediators of oocyte growth (estradiol-17β) and maturation (maturation-inducing hormone, MIH; 17α,20β-dihydroxy-4-pregnen-3-one, 17α,20β-DP in salmonid fishes; 17α,20β,21-trihydroxy-4-pregnen-3-one, 20β-S in sciaenid fishes). It is established that production of estradiol-17β and 17α,20β-DP by salmonid ovarian follicles occurs via the interaction of two cell layers, the thecal and granulosa cell layers (two-cell type model). A distinct shift in the salmonid steroidogenesis from estradiol-17β to 17α,20β-DP occurs in the ovarian follicle layer immediately prior to oocyte maturation. It is possible that this shift is a consequence of dramatic changes in the expression of the genes encoding various steroidogenic enzymes. As an initial step to address this question, we have isolated and characterized the cDNAs encoding a number of ovarian steroidogenic enzymes including the rainbow trout cholesterol side-chain cleavage cytochrome P-450, 3β-hydroxysteroid dehydrogenase (HSD), 17α-hydroxylase/17,20 lyase cytochrome P-450, aromatase cytochrome P-450 cDNAS as well as the pig 20β-HSD cDNA. Estradiol-17β stimulates the hepatic synthesis and secretion of a yolk precursor, vitellogenin. Vitellogenin is then transported to the ovary where it is selectively taken up into the oocyte by a receptor-mediated process involving specific cell-surface receptors. Estradiol-17β was also shown to induce the synthesis of egg membrane proteins in the liver. The maturation-inducing action of 17α,20β-DP and 20β-S is through the binding to the oocyte plasma membrane. This initial MIH-surface interaction is followed by the formation of the major mediator of MIH, maturation-promoting factor (MPF). We have purified MPF from mature oocytes of carp. Carp MPF consists of two components: the homolog of the cdc2+ gene product of fission yeast (p34cdc2) and cyclin B. The cdc2 kinase protein is present in immature oocytes as well as in oocytes induced to mature by 17α,20β-DP treatment, while cyclin B proteins can be detected only in mature oocytes. Addition of bacterially expressed goldfish cyclin B to the extracts of immature goldfish oocytes induced MPF activation. These results suggest that the appearance of cyclin B protein is a crucial step for 17α,20β-DP-induced oocyte maturation in fish.  相似文献   
169.
Soybean dwarf virus (SbDV), a Luteoviridae family member, causes dwarfing, yellowing and sterility of soybean (Glycine max), leading to one of the most serious problems in soybean production in northern Japan. Previous studies revealed that the Indonesian soybean cultivar ‘Wilis’ is resistant to SbDV and that the resistance can be introduced into Japanese cultivars. A major QTL for SbDV resistance has been reported between SSR markers Sat_217 and Satt211 on chromosome 5. In this study, we named this QTL Rsdv1 (resistance to SbDV) and developed near-isogenic lines incorporating Rsdv1 (Rsdv1-NILs) using Sat_217 and Satt211 markers. The Rsdv1-NILs were resistant to SbDV in greenhouse inoculation and field tests, indicating that Rsdv1 alone is sufficient for the resistance phenotype. We fine-mapped Rsdv1 within the 44-kb region between Sat_11 and Sct_13. None of the six genes predicted in this region was closely related to known virus resistance genes in plants. Thus, Rsdv1 may confer resistance by a previously unknown mechanism. We suggest that Rsdv1 may be a useful source for the Japanese soybean breeding program to introduce SbDV resistance.  相似文献   
170.
Seasonal and spatial variability of litterfall and NO3 and NH4+ leaching from the litter layer and 5-cm soil depth were investigated along a slope in a tropical dry evergreen forest in northeastern Thailand. Using ion exchange resin and buried bag methods, the vertical flux and transformation of inorganic nitrogen (N) were observed during four periods (dry, early wet, middle wet, and late wet seasons) at 15 subplots in a 180-m × 40-m rectangular plot on the slope. Annual N input via litterfall and inorganic N leached from the litter layer and from 5-cm depth soil were 12.5, 6.9, and 3.7 g N m−2 year−1, respectively, whereas net mineralization and the inorganic N pool in 0–5-cm soil were 7.1 g N m−2 year−1 and 1.4 g N m−2, respectively. During the early wet season (90 days), we observed 82% and 74% of annual NO3 leaching from the litter layer and 5-cm soil depth, respectively. Higher N input via leaf litterfall in the dry season and via precipitation in the early wet season may have led to higher NO3 leaching rate from litter and surface soil layers during the early wet season. Large spatial variability in both NO3 vertical flux and litterfall was also observed within stands. Small-scale spatial patterns of total N input via litterfall were significantly correlated with NO3 leaching rate from the surface soil layer. In tropical dry evergreen forests, litterfall variability may be crucial to the remarkable seasonal changes and spatial variation in annual NO3 vertical flux in surface soil layers.  相似文献   
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