全文获取类型
收费全文 | 215篇 |
免费 | 13篇 |
专业分类
林业 | 13篇 |
农学 | 11篇 |
基础科学 | 1篇 |
58篇 | |
综合类 | 8篇 |
农作物 | 54篇 |
水产渔业 | 25篇 |
畜牧兽医 | 43篇 |
园艺 | 4篇 |
植物保护 | 11篇 |
出版年
2022年 | 14篇 |
2021年 | 15篇 |
2020年 | 13篇 |
2019年 | 11篇 |
2018年 | 16篇 |
2017年 | 22篇 |
2016年 | 22篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 27篇 |
2012年 | 14篇 |
2011年 | 17篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 16篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 1篇 |
2000年 | 1篇 |
1985年 | 1篇 |
1983年 | 2篇 |
排序方式: 共有228条查询结果,搜索用时 0 毫秒
151.
152.
Precision Agriculture - The majority of the volume in a plant cell is water. Therefore, the growth and metabolism of plants are highly dependent on the changes in plant water content. To optimize... 相似文献
153.
Samaneh Saberi Kazem Zendehdel Sahar Jahangiri Yeganeh Talebkhan Afshin Abdirad Nazanin Mohajerani Maryam Bababeik Najmeh Karami Maryam Esmaili Akbar Oghalaie Parisa Hassanpour Neda Amini Mohammad Ali Mohagheghi Mahmoud Eshagh Hossieni Marjan Mohammadi 《Iranian Biomedical Journal》2012,16(4):179-184
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154.
Maryam KHALAJ Abdol Rahim ABBASI Takehito TSUJI Yasuo MORITOMO Kenichi SHIMOJO Tetsuo KUNIEDA 《Animal Science Journal》2006,77(1):122-125
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
155.
Background: During antigen capture and processing, mature dendritic cells (DC) express large amounts of peptide-MHC complexes and accessory molecules on their surface. DC are antigen-presenting cells that have an important role in tolerance and autoimmunity. The transforming growth factor-beta1 (TGF-Beta1) cytokine has a regulatory role on the immune and non-immune cells. The aim of this study is to evaluate the effect of TGF-Beta1 on the induction of human leukocyte antigen-G (HLA-G) expression on the DC which is derived from monocyte. Methods: In this study, we evaluated the effect of TGF-Beta1 in induction HLA-G expression on the monocyte-derived DC by flowcytometry and then CD4+ T cell proliferative responses in the presence of DC-treated TGF-Beta1 was studied. Results: The results of this study showed that DC bearing HLA-G down-regulated activation of CD4+ T cells and production of IL-6 and IL-17 in comparison with control (P<0.05). Conclusion: It is concluded that TGF-Beta1 has an important regulatory role in CD4+ T cell proliferation by increasing HLA-G on DC and these cells can probably prevent unexpected immune responses in vivo. 相似文献
156.
157.
MA Shokrgozar M Fattahi S Bonakdar I Ragerdi Kashani M Majidi N Haghighipour V Bayati H Sanati SN Saeedi 《Iranian Biomedical Journal》2012,16(2):68-76
Background: Wound healing of burned skin remains a major goal in public health. Previous reports showed that the bone marrow stem cells were potent in keratinization and vascularization of full thickness skin wounds. Methods: In this study, mesenchymal stem cells were derived from rat adipose tissues and characterized by flowcytometry. Staining methods were used to evaluate their differentiation ability. A collagen-chitosan scaffold was prepared by freeze-drying method and crosslinked by carbodiimide-based crosslinker. Results: The results of immunecytochemistry and PCR experiments confirmed the adipose-derived stem cells (ASC) in differentiation to the keratinocytes under the treatment of keratinocyte growth factor. The isolated ASC were seeded on the scaffolds and implanted at the prepared wounds. The scaffolds without cells were considered as a control and implanted on the other side of the rat. Histopathological analyses confirmed the formation of new tissue on the scaffold-cell side after 14 days with the formation of dermis and epidermis. Conclusion: These results indicated the capacity of ASC in differentiation to keratinocytes and also wound healing in vivo. Key Words: Tissue engineering, Keratinocytes, Mesenchymal stem cells 相似文献
158.
Roghieh Safari Seyed Hossein Hoseinifar Maryam Dadar Masoud Sattari Mina Rahbar 《Aquaculture Research》2019,50(9):2621-2627
This study investigates the effects of Coriander (C. sativum) on the growth, antioxidant, and immune‐associated genes and serum and mucosal immune parameters in zebrafish (D. rerio). The experimental fish were treated with 0 [control], 5, 10 and 20 g/kg coriander supplemented diets for 8 weeks. The results revealed that coriander remarkably increased mucosal immune parameters (the total Immunoglobulin, protease and lysozyme activity). The highest levels of the measured parameters were noticed in 20 g/kg CP treatment. Also, the zebrafish fed 20 g/kg coriander powder showed significantly higher expression gene for lysozyme and TNF‐alpha. The same results were noticed in case of IL‐1B gene expression. In case of sod gene expression there was no significant difference between treatments. However, regarding cat gene expression, significant difference was noticed between 20 g/kg CP treatment and other groups. In addition, no significant changes were observed between coriander fed zebrafish and control treatments regarding GH gene expression level, although IGF‐I remarkable up‐regulate in 20 g/kg coriander powder treatment compared other groups. In conclusion, it can be proposed that dietary Coriander powder can improve mucosal immune parameters and immune and antioxidant genes expression. 相似文献
159.
Antibacterial activity of immobilized silver nanoparticles on TEPA‐Den‐SiO2 against shrimp pathogen,Vibrio sp. Persian1 下载免费PDF全文
Mehrdad Sarkheil Iman Sourinejad Maryam Mirbakhsh Davood Kordestani Seyed Ali Johari 《Aquaculture Research》2017,48(5):2120-2132
In this study, we prepared silver nanoparticles immobilized onto silica sand beads as an antibacterial material against pathogenic luminous Vibrio sp. Persian1. Silica beads were modified with 3‐aminopropyltriethoxysilane (APTES), cyanuric chlorid and tetraethylene pentamine, and silver nanoparticles were generated in various concentrations (0.5, 1, and 2 mM g?1 of silica beads) of AgNO3 on the surface using chemical reduction. Ag/TEPA‐Den‐SiO2 samples were characterized by TEM, FE‐SEM/EDS, FT‐IR and ICP OES and their antibacterial activity assayed by zone of inhibition and test tube tests against pathogenic Vibrio sp. The results of the zone inhibitory test revealed that all the Ag/TEPA‐Den‐SiO2 samples had an antibacterial effect against luminous Vibrio sp. Persian1. In addition, the tube test results showed 100% killing of bacteria in 2 h contact period. Ag/TEPA‐Den‐SiO2 samples maintained their antibacterial activity after 14‐day immersion in seawater by slow release of silver ions. These results suggest that Ag/TEPA‐Den‐SiO2 substrates could be effective antibacterial materials for disinfection of seawater used to culture Penaeid shrimp larvae. 相似文献
160.
The effect of dietary taurine on growth performance and liver histopathology in Persian sturgeon,Acipenser persicus (Borodin, 1897) fed plant‐based diet 下载免费PDF全文
Seyyed Morteza Hoseini Seyed Abbas Hosseini Soheyl Eskandari Maryam Amirahmadi Mohammad Soudagar 《Aquaculture Research》2017,48(8):4184-4196
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