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91.
The effectiveness of subcritical liquid water processing for extraction of antioxidants from the leaves of Eucalyptus grandis biomass was evaluated by determining the capability of the processed samples to scavenge peroxynitrite radicals in vitro, as compared with the extracts obtained by conventional extraction. Pyrogallol (1), 5-hydroxymethyl-2-furaldehyde (2), and 4,4,6,6-tetramethyl-3,5-dioxo-cyclohex-1-enecarboxylic acid (3) were identified as the major products obtained from the subcritical liquid water extracts. Among these, pyrogallol (1) exhibited stronger antioxidant activity than butylated hydroxytoluene, which was used as a standard for the antioxidant activity measurement. This research was presented at the conference of the Japan Society for Bioscience, Biotechnology, and Agrochemistry (JSBBA) in Tokyo, March 2007.  相似文献   
92.
OBJECTIVE: To compare right atrium incision (RAI) and right ventricular outflow incisions (RVI) for surgical repair of membranous ventricular septal defect (VSD) facilitated by cardiopulmonary bypass (CPB). STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=10) with VSD. METHODS: Medical records of dogs that had VSD repair were reviewed. Membranous VSD without any malformation and abnormality was confirmed on several clinical examinations and by angiocardiography. RAI (5 dogs) and RVI (5 dogs) was used for VSD access and repair facilitated by CPB. Procedure comparison was by surgical duration, postoperative recovery period, and occurrence of postoperative arrhythmia. RESULTS: Duration of surgery was similar for RAI and RVI; however, postoperative recovery time was significantly reduced with RAI. Significant moderate operative damage occurred with right atrium incision. CONCLUSIONS: Right atrium incision was more effective than RVI for repair of membranous VSD using CPB. CLINICAL RELEVANCE: RAI should be considered in preference to RVI for repair of membranous VSD using CPB.  相似文献   
93.
Hydraulic resistance in plants is one of the most important factors responsible for changes in leaf water potential that is an indicator of plant water stress. Although the hydraulic resistance to passive water transport (Rpa) is a robust index in paddy rice (Oryza sativa), measurement is both time-consuming and labour-intensive. Here, we describe on a quick method to measure hydraulic resistance to osmotic water transport (Ros) by measuring the xylem sap exudation rate and osmotic water potential. In a greenhouse experiment, Ros responded significantly to soil temperature, but under field conditions soil temperature varied considerably less than air temperature. In the field experiment, Ros of six rice cultivars at two growth stages was strongly positively correlated with Rpa. We conclude that measuring Ros could be used to evaluate root water transport capacity in paddy rice under conditions with adequate soil water.  相似文献   
94.
Recent progress in rice genomics has promoted the identification of quantitative trait loci (QTLs) associated with yield and its related traits. SPIKE, a QTL controlling spikelet number per panicle, and GPS, a QTL controlling leaf photosynthesis rate, were identical to NAL1. To assess the effect of SPIKE/GPS on yield potential, we compared DNA sequences of these alleles and conducted yield experiments in the field of Japan using the near-isogenic lines NIL-SPIKE (allele from Daringan in IR 64 genetic background), NIL-GPS (allele from Koshihikari in Takanari genetic background), and a chromosome segment substitution line, SL2115 (allele from Koshihikari in IR 64 genetic background). Despite the two SNPs in the promoter regions between Koshihikari and Daringan, both alleles were effective to increase the number of spikelets per panicle both in Takanari and IR 64 backgrounds. However, the extent of the increase was smaller and unstable in Takanari background than that in IR 64 background. In addition, SPIKE/GPS improved percentage of filled spikelets only in the IR 64 background. These results suggest that the effects of SPIKE/GPS alleles are similar but are affected by the difference of the genetic backgrounds. Because the increasing effect of spikelets number per panicle was canceled by the decrease of the number of panicles, which seems to be affected by environmental factors, none of NIL-SPIKE, SL2115, or NIL-GPS significantly out-yielded their parental cultivars. These results indicate the importance to consider genetic backgrounds and QTL-environment interaction toward the future use of SPIKE/GPS.  相似文献   
95.
We report a strategy to expand the pore aperture of metal-organic frameworks (MOFs) into a previously unattained size regime (>32 angstroms). Specifically, the systematic expansion of a well-known MOF structure, MOF-74, from its original link of one phenylene ring (I) to two, three, four, five, six, seven, nine, and eleven (II to XI, respectively), afforded an isoreticular series of MOF-74 structures (termed IRMOF-74-I to XI) with pore apertures ranging from 14 to 98 angstroms. All members of this series have noninterpenetrating structures and exhibit robust architectures, as evidenced by their permanent porosity and high thermal stability (up to 300°C). The pore apertures of an oligoethylene glycol-functionalized IRMOF-74-VII and IRMOF-74-IX are large enough for natural proteins to enter the pores.  相似文献   
96.
Purine nucleotides regulate the cellular functions in the animal body. The current study evaluates the comparative efficacy of dietary purine nucleotides, that is, adenosine monophosphate (AMP), guanosine monophosphate (GMP) and inosine monophosphate (IMP) in red sea bream Pagrus major. Semi‐purified basal diet was formulated (Control, D1) containing 550 g/kg protein, supplemented with purine nucleotides AMP, GMP and IMP at their optimum supplementation level (2, 4 and 4 g/kg) to formulate the experimental diet groups D2, D3 and D4, respectively. Initial weight of 3.5 ± 0.01 g fish was randomly fed test diets in triplicate. After 56 days, % weight gain (p = .003), specific growth rate (p = .003) and apparent lipid digestibility (p = .04) were significantly higher in fish fed diet group D4 followed by D3 and D2. Supplemented groups showed significantly higher feed intake in comparison to control (p = .001). Supplemented groups showed significantly increased and decreased NBT (p = .003) and CAT (p = .003) activity, respectively. Fish fed IMP supplemented diets had significantly lower blood urea nitrogen (p = .04), glutamyl oxaloacetic transaminase (p = .04) and glutamic‐pyruvate transaminase (p = .001) followed by other supplemented groups. Supplemented diet groups showed enhanced stress resistance. Interestingly, D2 and D4 groups showed best oxidative stress status of fish. Therefore, these results indicated that among purine nucleotides, supplementation of IMP could be a more effective nucleotide as functional supplement in red sea bream diet.  相似文献   
97.
Recent studies have demonstrated the benefits of nitric oxide (NO) on myocardial hypertrophy and myocardial fibrosis. It was suggested that NO has a protective effect on myocardial cell through the neurohormonal system. This effect serves to highlight the important role of NO in maintaining the function and form of heart with chronic heart failure. However, there are no known reports about on the effect of prolonged administration of nitrate on pressure over-load heart. This study was conducted to examine the long-term effect of oral nitrate therapy in rats with pressure-overloaded heart. An abdominal aorta constricted (AC) model of pressure-overloaded heart was created in male Wistar rats. Sustained release isosorbide dinitrate (sr-ISDN) (5 mg/kg once a daily) was administered to the rats once a daily for 12 weeks. The animals were euthanized during the study period, and the heart was collected and weighed. Histopathological examination was performed to evaluate the effect of sr-ISDN on myocardial hypertrophy and fibrosis. The ratio of heart to body weight increased significantly in AC rat and this increase was significantly prevented by sr-ISDN treatment. Histopathological examination showed significant increase in fibrotic area of AC rat compared to sham rat, this increase was inhibited by sr-ISDN treatment. Cardiomyocyte transverse diameter was significantly increased in AC rat compared with sham rat, but this increase tended to decrease by sr-ISDN treatment. In conclusion, intermittent administration with sr-ISDN has mild effect in inhibiting cardiac hypertrophy and marked effect in inhibiting fibrosis due to pressure-overload.  相似文献   
98.
Canine histiocytic sarcoma is an aggressive, fatal neoplastic disease with a poor prognosis. Lomustine is generally accepted as the first‐line systemic therapy, although this compound does not provide complete regression. Therefore, research into a novel approach against canine histiocytic sarcoma is needed. However, anti‐tumour effects of oncolytic therapy using reovirus against histiocytic sarcoma are unknown. Here, we showed that reovirus has oncolytic activity in canine histiocytic sarcoma cell lines in vitro and in vivo. We found that reovirus can replicate and induce caspase‐dependent apoptosis in canine histiocytic sarcoma cell lines. A single intra‐tumoural injection of reovirus completely suppressed the growth of subcutaneously grafted tumours in NOD/SCID mice. Additionally, we demonstrated that susceptibility to reovirus‐induced cell death was attributable to the extent of expression of type I interferons induced by reovirus infection in vitro. In conclusion, oncolytic reovirus appears to be an effective treatment option for histiocytic sarcoma, and therefore warrants further investigation in early clinical trials.  相似文献   
99.
100.
The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) causes resistance to nitrosoureas in various human cancers. In this study, we analyzed the correlation between canine lymphomas and MGMT in vitro. Two of five canine lymphoma cell lines required higher concentrations of lomustine to inhibit cell growth by 50%, but their sensitivity to the drug increased when they were cultured with an MGMT inhibitor. Fluorometric oligonucleotide assay and real-time polymerase chain reaction of these cell lines revealed MGMT activity and high MGMT mRNA expression, respectively. We analyzed the methylation status of the CpG islands of the canine MGMT gene by the bisulfite-sequencing method. Unlike human cells, the canine lymphoma cell lines did not show significant correlation between methylation status and MGMT suppression levels. Our results suggest that in canine lymphoma MGMT activity may influence sensitivity to nitrosoureas; thus, inhibition of MGMT activity would benefit nitrosourea-resistant patients. Additional studies are necessary to elucidate the mechanism of regulation of MGMT expression.  相似文献   
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