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191.
Background:Glioblastoma multiforme is the most invasive and lethal form of brain cancer with unclear etiology. Our study aimed to investigate the molecular prevalence of HCMV and EBV infections in patients with GBM. Methods:This case-control study was conducted on 42 FFPE brain tumor samples from GBM patients and 42 brain autopsies from subjects without neurological disorders. The presence of EBV and HCMV DNA was determined, using PCR and nested-PCR assays, respectively. Results:HCMV DNA was detected in 3 out of 42 (7.1%) of GBM samples and was absent from the control group (p = 0.07). Importantly, EBV DNA was detected in 9 out of 42 (21.4%) brain tissue specimens of GBM subjects, but again in none of the control group (p = 0.001). Conclusion:Our findings indicate that infection with EBV is associated with GBM. Key Words: Brain tumor, Epstein-Barr virus, Glioblastoma, Human cytomegalovirus  相似文献   
192.
Background:FH, a hereditary disorder, is caused by pathogenic variants in the LDLR, APOB, and PCSK9 genes. This study has assessed genetic variants in a family, clinically diagnosed with FH. Methods:A family was recruited from MASHAD study in Iran with possible FH based on the Simon Broom criteria. The DNA sample of an affected individual (proband) was analyzed using WES, followed by bioinformatics and segregation analyses. Results:A novel splice site variant (c.345-2A>G) was detected in the LDLRAP1 gene, which was segregated in all affected family members. Moreover, HMGCR rs3846662 g.23092A>G was found to be homozygous (G/G) in the proband, probably leading to reduced response to simvastatin and pravastatin. Conclusion:LDLRAP1 c.345-2A>G could alter the PTB, which acts as an important part of biological pathways related to lipid metabolism. Key Words: Genetic research, LDLRAP1, Hypercholesterolemia, Hydroxymethylglutaryl-CoA Reductase Inhibitors  相似文献   
193.
The present study investigated the optimum dietary protein level for the maturation of adult Pangasianodon hypophthalmus broodstock. Four isocaloric diets containing 250, 300, 350 and 400 g kg?1 of protein levels were prepared and presented to triplicate groups of fish. The fish (mean weight 770 ± 17.23 g and 712 ± 23.42 g for females and males respectively) were stocked in outdoor canvas tanks (4 m × 1 m × 1 m) at a stocking density of 20 fish/tank with a male: female ratio of 1:4. The fish were fed the test diets to satiation twice daily for 6 months. Gonadosomatic index (GSI) and fecundity were similar among fish fed dietary protein levels, higher than those fed on the 250 g kg?1. Final weight, weight gain, oocyte weight were significantly highest (< 0.05) for the fish fed 350 and 400 g kg?1 dietary protein treatments. Only the 350 g kg?1 dietary protein treatment resulted in significantly best ovipositor diameter and % ripe egg. Amino acid levels were highest in the muscle followed by the oocyte and liver of fish fed 350 and 400 g kg?1 dietary protein levels. The present results suggested that a dietary protein level of 350 g kg?1 can be recommended for the development of P. hypophthalmus broodstock.  相似文献   
194.
Journal of Plant Diseases and Protection - Stem rot of tomato caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) results in economic yield loss worldwide. Previous studies have...  相似文献   
195.
Polyglycolic acid-poly lactic glycolic acid (PGA-PLGA) electrospun nanofibers containing silver nanoparticles have been produced and twisted into the nanofibrous yarn. The morphology of nanofibers and produced yarns, as well as the mechanical properties of the yarns, were investigated. Furthermore, in vitro antibacterial properties and in vitro degradation behavior of yarns containing various silver nanoparticles were studied. SEM images confirmed that the addition of the silver nanoparticles into the polymer solution increases the fiber diameters. The result of the mechanical test of the yarns alone and used in two different forms of the knots was measured and results showed that the strength of the yarns without the knot was significantly more than that of others. The biodegradability test showed that the mechanical properties and the weight of the yarns were quickly reduced after subjecting to in vitro condition. The result of the antibacterial test indicated that the nanofiber yarns containing %3 silver nanoparticles were the most appropriate sample with a considerably antibacterial activity against both gram-positive bacterium Staphylococcus aureus and gram-negative bacterium Escherichia Coli with inhibition zones of 8.1 and 9.5 mm, respectively; which demonstrated that silver nanoparticles retained their effectiveness after the electrospinning process. Therefore the nanofibrous yarns containing silver nanoparticles could be successfully produced by the electrospinning process with the proper antibacterial property as a candidate for the surgical sutures.  相似文献   
196.
Evaluating agricultural loss due to flooding is essential for defining an appropriate risk level in flood management projects. This research introduces a method for computing annual damage risk for rice fields with respect to both spatial and temporal pattern of floods, while considering the effect of crop growth stages on the total damage. For finding the spatial pattern of floods, HEC-RAS was employed to derive selected physical parameters of floods of interest and then a physical loss function was used to calculate the unconditional loss over flood prone areas. A time-dependent loss function was introduced for rice to determine the effect of growth on damages derived through the physical loss function. Due to the seasonal nature of agricultural risk, frequency analysis was performed for seasonal discharges for each growth stage of rice. A method was introduced to use the concept of Expected Annual Damage in agricultural fields. A method called “AGEAD” was introduced for evaluating short-term risk for agricultural activities considering their inherent spatial and temporal characteristics. Results showed that damages evaluated by employing AGEAD were completely different from what was obtained by applying a flood of defined return period, i.e. from the results of long-term risk evaluation. While it is common to attribute a unique predicted loss to all flood prone areas, AGEAD application showed that different zones in flooded paddy fields were subjected to different amount of damages from 100 to 0%.  相似文献   
197.
ABSTRACT

The proximate content, fatty acids composition, and nutritional quality index (NQI) of Macrobrachium nipponense at three habitats in the Anzali wetland in Iran were investigated as a potential source for human consumption. The highest amounts of protein, lipid, ash, and energy contents in muscle of M. nipponense were showed in autumn (non-reproductive season) (p < 0.05). The main monounsaturated fatty acids (MUFA) were oleic acid (C18:1 n9 C, C18:1 ω9 T) and palmitoleic acid (C16:1). Moreover, the main polyunsaturated fatty acids (PUFA) were docosahexaenoic acid (DHA, C22:6 n3), eicosapentaenoic acid (EPA, C20:5n3), arachidonic acid (ARA, C20:4 n6), linoleic acid (LA, C18:2 ω6), and α-linolenic acid (ALA, C18:3 n3). The predominant individual saturated fatty acid (SFA) was palmitic acid (0.07–13.4%), while oleic acid (14.7–26.3%), EPA (3.5–12.7%) and linoleic acid (0.04–14.9%) represented the most abundant individual MUFA and PUFA in M. nipponense. The highest mean value of EPA+DHA (14.0), n3/n6 (1.02), ΣMUFA/ΣSFA (1.05), ΣPUFA/ΣSFA (1.04), and EPA/DHA (3.8) ratios in M. nipponense was in autumn. The range of atherogenicity index (AI) and thrombogenicity index (TI) was much lower, from 0.42 to 0.6 and from 0.33 to 0.57, respectively, in terms of season. The results obtained in the present study show that M. nipponense is an excellent nutritional food source in the Anzali wetland.  相似文献   
198.
Background: The effect of ovariectomy and accompanying sudden loss of circulating gonad hormones on spatial learning performance in the young adult rats was examined. We hypothesized that spatial learning and memory in a considerable number of women who undergo a surgical menopause and estrogen deprivation before their natural menopause be impaired. Methods: In this study, we used 26 Wistar rats (approximately five months of age) and divided them into two groups: intact and ovariectomized (OVX). They were tested for spatial reference memory in Morris water maze 6 weeks after OVX. Results: The results showed that the performance of OVX group in the water maze was significantly lower than the control group. Although, mean path length decreased across blocks in both groups, OVX rats had significantly longer path length than controls across blocks 2-6 (P<0.05). OVX rats had lower percent of total time spent in target quarter than controls in probe trials (P<0.05). Body weight gain was significant only in OVX group during the experiment (P<0.05). Plasma estrogen significantly decreased after OVX (P<0.05). Conclusion: This finding provides further evidence for the role of estrogen, a gonadal steroid hormone, in the manipulation of functions related to learning and memory. It is suggested that estrogen loss following OVX impaired spatial reference memory in young adult rats. Our results suggest that it is necessary to protect women who undergo a surgical menopause before their natural menopause from cognition impairments.  相似文献   
199.
Journal of Soils and Sediments - The difference in copper (Cu) availability between soils can be a result of different distribution of Cu forms in various size fractions of aggregates. This study...  相似文献   
200.
This research is performed for evaluating the morphogenesis responses of thin cell layers (TCL) of alfalfa (Medicago sativa cv. Karysary) hypocotyls. TCLs (0.1–0.5 mm) were obtained from sterile hypocotyls that were cultured to SH medium containing various combinations of 2,4-D and kin (0, 0.5, 1, 1.5 and 2 mg/l). Unexpectedly, the percentage of callus induction (PCI) and Callus diameter (CD) were not affected by different concentrations of 2,4-D and kin. PCI was 100% without any correlation to hormonal combinations. Significantly the difference between concentrations of 2,4-D and kin for percentage of somatic embryogenesis (PSE) was observed (p < 0.01) so that, the maximum PSE occurred with 1.5 mg/l 2,4-D and without kin. The 2,4-D and kin interaction was not significant for PSE showing that each of these hormones affected by PSE independently. The number of embryoids (NE) was significantly different on the various concentrations of 2,4-D (p < 0.05) and maximum NEs were observed on 1.5 mg/l 2,4-D and without kin.  相似文献   
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