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171.
Mycorrhiza can improve plant growth and increase nutrient uptake. This study was conducted as factorial experiment based on complete random design (CRD) to study effects of mycorrhiza inoculation under limited iron (Fe) condition on antioxidant activity, phenol content and photosynthesis trait of cucumber (Cucumis sativus cv. N3). Treatments were Johnson modified nutrient solution (MNS) with 25% Fe (MNS1) = 0.57 mg/L Fe, 50% (MNS2) = 1.14 mg/L Fe and 100% (MNS3) = 2.3 mg/L Fe and mycorrhiza inoculation (M+) and non-mycorrhiza inoculation (M?) with 3 replications under hydroponic conditions. The results showed that plant growth and shoot phenol content decreased in the MNS1 treatment; whereas phenol content of the root exudates and antioxidant activity significantly increased in this treatment. All photosynthesis attribute increased in the MNS3 treatment. Mycorrhiza inoculation increased plant growth, phenol content, antioxidant activity and photosynthesis trait of cucumber. Also, mycorrhiza inoculation enhanced SPAD value in the MNS2 treatment and photosynthesis rate, transpiration and mesophyll conductance in all the modified nutrient solutions. Moreover, mycorrhiza symbiosis was stimulated by the internal carbon dioxide (CO2) content of the stomata in the MNS2 and MNS3 treatments. Furthermore, Mycorrhiza inoculation improved phenol content of the shoots and roots in all the nutrient solutions, whereas antioxidant activity was affected by mycorrhiza inoculation only in the MNS2 treatment.  相似文献   
172.

Background

Attempts for early detection of gastric cancer have recently focused on host''s genetic susceptibility factors and gene-environment interactions. We have, herein, studied the association of MTHFR C677T single nucleotide polymorphism (SNP) and its interaction with Helicobacter pylori infection, smoking, age and gender on the risk of gastric cancer among an Iranian population.

Methods

Gastric cancer patients (n = 450) and cancer-free controls (n = 780) were studied for serum H. pylori-specific IgG antibodies by ELISA and MTHFR C677T polymorphism (SNP) by PCR-RFLP. Demographic and life style data were collected through patient interviews. Unconditional logistic regression model estimated odds ratio (OR) and the corresponding 95% confidence intervals (CI).

Results

The interactions of MTHFR genotype with H. pylori infection (P = 0.03), age (P = 0.049) and gender (P = 0.007) were statistically significant. Accordingly, MTHFR C677T carriers who were also positive for H. pylori infection exhibited 80% (OR = 1.8, 95% CI = 1.0-2.9) significant excess risk of non-cardia gastric cancer. Furthermore, subjects over the age of 50 or female subjects carrying MTHFR C677T SNP showed 40 (OR = 1.4, 95% CI = 1.0-2.0) and 100 (OR = 2.0, 95% CI = 1.2-3.2) percent increased risk of gastric cancer, respectively.

Conclusion

MTHFR C677T SNP seems to increase the risk of gastric cancer and the effect is significantly inflated by interactions with H. pylori infection, age and gender. Key Words: Helicobacter pylori, Smoking, Gender identity, Age group, Methylenetetrahydrofolate reductase  相似文献   
173.
This experiment was conducted to illustrate the effect of dietary taurine levels on Persian sturgeon, Acipenser persicus (mean weight of ~35 g) fed plant‐based diet. A basal diet containing low level of fishmeal (19%) was formulated containing 0.05% endogenous taurine (control diet). To this diet were added five levels of exogenous taurine: 0.25 (0.25T), 0.5 (0.5T), 0.8 (0.8T), 1.2 (1.2T) and 1.6% (1.6T). These diets were fed to the experimental fish for 42 days. Results showed that growth performance decreased and food conversion ratio increased as dietary taurine increased, although no significant difference was observed between the control and 0.25T treatments. Increased dietary taurine led to increased carcass moisture and decreased carcass lipid percentages. Feed intake was significantly and negatively correlated with dietary taurine. Carcass taurine content significantly increased with dietary taurine elevation up to 1.2% and then decreased. Hepatic taurine content showed a significant increase in 0.25T treatment and then decreased along with dietary taurine elevation and reached the control values at 1.6% taurine level. Dietary taurine elevation led to more hepatic damages compared to the control. In conclusion, although within the range reported for other studied fish, the tested taurine levels in this study might be supra‐optimal causing adverse effects in Persian sturgeon and further study with lower taurine levels is encouraged.  相似文献   
174.
Hemophilia A is a severe congenital bleeding disorder characterized by subcutaneous hematoma and hemorrhage into muscles resulting from a deficiency of blood coagulation factor VIII. The authors have recently reported two cases of hemophilia A in Japanese Brown cattle and identified a nucleotide substitution in the factor VIII gene, resulting in an amino acid substitution of Leu to His, as a possible cause of the deficiency. In the present study, a simple and effective polymerase chain reaction (PCR)‐based diagnostic method was developed to identify carriers of this disorder, using a mismatch primer in combination with restriction enzyme digestion. The PCR reaction amplified a 118 bp fragment, which was not digested by the BspT104I restriction enzyme in affected animals but was digested into two fragments in normal animals. Both digested and undigested fragments were observed in carrier animals. This method was applied to identify the carriers of hemophilia A in a population of Japanese Brown cattle. By screening 155 DNA samples from Japanese Brown cattle, except for the dam of the two probands, no carriers were identified. It was therefore concluded that the probands represent isolated cases of hemophilia A, and that the frequency of the mutant allele in the Japanese Brown cattle population is very low.  相似文献   
175.
176.
Cotton(Gossypium hirsutum L.) is utilized commercially in the production of textile, clothing, and household goods. Its growth is affected by various environmental conditions such as soil, climate, and water supply. Irrigation is one of the most important factors for crop management. This research was designed with the aim of studying the biochemical and anatomical features of two genotypes of cottonseed(Latif and Golestan) in order to determine optimum irrigation. Protein, starch, gossypol gland, total soluble protein, starch content, and the anatomical structure of the cotton seeds were investigated. The data were analyzed using the SAS Software. The results showed that when rainfed, Golestan genotype seeds had a larger number of secretory cavities, soluble protein, and starch compared to Latif seeds. There was also a noticeable difference in the size of the seeds. Cellulosic cell walls and protein particles were also observed in the seed structure under induced water stress conditions. It can therefore be concluded that in response to water shortage, there was a noticeable change in the morphometric, anatomic, and biochemical features of the cottonseeds. It can be concluded that when rainfed, the Golestan genotype of cottonseed has more compatibility than the Latif genotype. In general, the application of different levels of irrigation showed that at moderate levels of irrigation, anatomical features appeared more normal. The observations indicate that at high levels of irrigation, some cells begin to dehisce due to osmotic stress, which results in a lack of accurate formation of tissue structures. The Golestan genotype is therefore the best suited for dryland farming.  相似文献   
177.

Background:

The serum concentration of high-density lipoprotein cholesterol (HDL-C) is one of the important heritable risk factors for cardiovascular disease and is a target for therapeutic intervention. In this study, we aimed to evaluate the effects of lecithin cholesterol acyltransferase (LCAT) gene polymorphism rs5923 on LCAT enzyme activity and serum HDL-C concentration.

Methods:

The study population was selected from consecutive individuals with HDL-C ≤ 5th percentile (n = 73) and extremely high HDL-C ≥ 95th percentile (n = 57) who had participated in the Tehran Lipid and Glucose Study. The rs5923 polymorphism was genotyped using direct sequencing. LCAT activity was measured by fluorometric assay kit, and lipid concentrations were measured using the enzymatic colorimetric method.

Results:

The genotype frequencies were significantly different between the high HDL-C group (CC 94.7%, CT 5.3%) and the low HDL-C group (CC 83.6%, CT 16.4%) (P = 0.048). The T-allele frequencies in subjects with low and high HDL-C were 0.082 and 0.026, respectively (P = 0.16). The association of the single-nucleotide polymorphism rs5923 with low HDL-C was not statistically significant after adjustment for age, sex, and BMI (odd ratio = 2.65, 95% confidence interval = 0.32-21.5, P = 0.36, regression logistic analysis). Also, the effects of LCAT enzyme activity did not depend on the HDL-C level (P = 0.24).

Conclusion:

rs5923 polymorphism is not associated with low HDL-C levels in Iranian population. Key Words: Polymorphism, Single nucleotide, Lipoproteins  相似文献   
178.
A hydroponic experiment was conducted based on completely randomized design (CRD) to study the effects of Selenium (Se) on tomato (Lycopersicum esculentum L), cv. Foria with three replications. Treatments included 3, 5, 7, and 10 µM sodium selenite (Na2SeO3) and 0 as control. The results showed that selenium (Se) at 7 µM was beneficial to photosynthesis pigments. The highest relative water content was resulted from the 3 µM Se treatment. The membrane stability index was decreased with increasing Se concentration up to 10 µM Se. An increase in peroxidase (POD) activity occurred at the 3 µM Se level, and the catalase (CAT) activity was 80% higher than the control at the 7 µM Se level. In general, the highest root volume, leaf numbers, carotenoids content, and CAT activity were found at the 5 µM Se level, and Chlorophyll content increased at the 7 and 10 µM Se levels.  相似文献   
179.
Background:Pertussis is a current contagious bacterial disease caused by Bp. Given the prevalence of pertussis, development of new vaccines is important. This study was attempted to evaluate the expression of main virulence factors (PTX, PRN, and FHA) from Bp predominant strains and also compare the expression of these factors in the OMVs obtained from predominant circulating Bp isolate. Methods:The physicochemical features of the prepared OMVs were analyzed by electron microscopy and SDS-PAGE. The presence of the mentioned virulence factors was confirmed by Western blotting. BALB/c mice (n = 21) immunized with characterized OMVs were challenged intranasally with sublethal doses of Bp, to examine their protective capacity. Results:Electron microscopic examination of the OMVs indicated vesicles within the range of 40 to 200 nm. SDS-PAGE and Western blotting demonstrated the expression of all three main protective immunogens (PTX, PRN, and FHA), prevalent in the predominant, challenge, and vaccine strains, and OMVs of the predominant IR37 strain and BP134 vaccine strain. Significant differences were observed in lung bacterial counts between the immunized mice with OMV (30 CFU/lung) compared to the negative control group ((6 104 CFU/lung; p < 0.001). In mice immunized with OMVs (3 µg), the number of lungs recovered colonies after five days dropped at least five orders of magnitude compared to the control group. Conclusion:OMVs obtained from circulating isolates with the predominant profile may constitute a highly promising vaccine quality. They also can be proposed as a potential basic material for the development of new pertussis vaccine candidate. Key Words: Bordetella pertussis, Vaccines, Virulence factors  相似文献   
180.
Increasing water and fertilizer productivity stands as a relevant challenge for sustainable agriculture. Alternate furrow irrigation and surface fertigation have long been identified as water and fertilizer conserving techniques in agricultural lands. The objective of this study was to simulate water flow and fertilizer transport in the soil surface and in the soil profile for variable and fixed alternate furrow fertigation and for conventional furrow fertigation. An experimental data set was used to calibrate and validate two simulation models: a 1D surface fertigation model and the 2D subsurface water and solute transfer model HYDRUS-2D. Both models were combined to simulate the fertigation process in furrow irrigation. The surface fertigation model could successfully simulate runoff discharge and nitrate concentration for all irrigation treatments. Six soil hydraulic and solute transport parameters were inversely estimated using the Levenberg–Marquardt optimization technique. The outcome of this process calibrated HYDRUS-2D to the observed field data. HYDRUS-2D was run in validation mode, simulating water content and nitrate concentration in the soil profiles of the wet furrows, ridges and dry furrows at the upstream, middle and downstream parts of the experimental field. This model produced adequate agreement between measured and predicted soil water content and nitrate concentration. The combined model stands as a valuable tool to better design and manage fertigation in alternate and conventional furrow irrigation.  相似文献   
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