全文获取类型
收费全文 | 184篇 |
免费 | 9篇 |
专业分类
林业 | 8篇 |
农学 | 15篇 |
基础科学 | 1篇 |
45篇 | |
综合类 | 11篇 |
农作物 | 32篇 |
水产渔业 | 20篇 |
畜牧兽医 | 41篇 |
园艺 | 2篇 |
植物保护 | 18篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 12篇 |
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 9篇 |
2016年 | 3篇 |
2015年 | 7篇 |
2014年 | 7篇 |
2013年 | 16篇 |
2012年 | 9篇 |
2011年 | 12篇 |
2010年 | 6篇 |
2009年 | 7篇 |
2008年 | 5篇 |
2007年 | 3篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 2篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 5篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1978年 | 3篇 |
排序方式: 共有193条查询结果,搜索用时 15 毫秒
101.
E H Safar M E Azab H M Khalil M A Bebars H el Hady H M Khattab 《Folia parasitologica》1990,37(3):249-254
Sera from patients with ocular and visceral manifestations of toxocariasis were tested by precipitin absorption (PAT), counter-immunoelectrophoresis (CIEP), indirect fluorescent antibody (IFAT) and ELISA. The ocular cases revealed a percentage of positivity of 36% by PAT, 0% by CIEP, 32% and 28% by IFAT with embryonated egg (EE) and frozen section antigens (FS) respectively and 40% by ELISA. The visceral cases revealed 44% positively by PAT, 24% by CIEP 52% and 48% by IFAT with EE and FS respectively and 52% by ELISA. Statistical evaluation was done to interpret the results. 相似文献
102.
The effect of the fungicide, diclobutrazol, on the germination, growth, chloroplast pigment and sterol content of winter wheat seedlings has been studied. At 250 μEm it retards their germination and growth, producing smaller, darker green and apparently healthy young plants. This is largely due to the 2S,3S–enantiomeric component. The increased greenness is not due to a direct effect on chloroplast pigments. It inhibits sterol 14—demethylation, causing an increase in the content of 4α,14α–dimethyl sterols, and also increases the proportion of campesterol, a 24—methyl sterol, relative to that of the 24—ethyl sterols, stigmasterol and sitosterol. Both the 2R,3R– and 2S,3S–enantiomers appear to be able to cause these changes in sterol content. 相似文献
103.
An ethnobotanical survey was conducted among 31 local Arab practitioners living in Galilee, Negev, Golan Heights and West Bank. Seeing that the Arabic traditional medicine is in danger of disappearing, a multilevel program is required, involving the training of local practitioners, an establishment of a regional medicinal plant botanical garden and a field gene bank for plant preservation. 相似文献
104.
Thirteen hard red spring wheat genotypes in which seven genotypes had the same high molecular weight (HMW) glutenin subunits (2*, 7+9, 5+10) were compared for their physical-chemical and breadmaking properties. These samples were categorized into three groups based on their dough mixing and baking performances as follows: the strong dough (SD) group (six genotypes), characterized by the strongest dough mixing (average stability, 35 min); the good loaf (GL) group (four genotypes), characterized by the largest loaf volume; and the poor loaf (PL) group (three genotypes), characterized by the smallest loaf volume. Total flour proteins were fractionated into 0.5M salt-soluble proteins, 2% SDS-soluble proteins, and residue proteins (insoluble in SDS buffer). SDS-soluble proteins, residue proteins, and total flour proteins were analyzed by SDS-PAGE and densitometry procedures to determine the proportions of HMW glutenin subunits, medium molecular weight proteins, and low molecular weight proteins in relation to the total amount of proteins. No differences in the amount of salt-soluble proteins were found among the different groups of samples. Solubilities of gluten proteins (total proteins minus salt-soluble proteins) in SDS buffer were related to the differences in dough strength and baking quality among the three groups. The SD group had the lowest solubility and the PL group had the highest. SDS-PAGE analysis showed that SDS-soluble proteins of the SD group contained a smaller amount of HMW glutenin subunits than those of the GL and PL groups. The highest proportions of HMW glutenin subunits in total flour proteins were found in the SD group, while the PL group had the lowest percentage of HMW glutenin subunits in their total flour proteins. These results showed that the total quantities of HMW glutenin subunits played an important role in determining the dough mixing strength and breadmaking performance of hard red spring wheats. 相似文献
105.
Eman Maher Zahran Amgad Albohy Amira Khalil Alyaa Hatem Ibrahim Heba Ali Ahmed Ebaa M. El-Hossary Gerhard Bringmann Usama Ramadan Abdelmohsen 《Marine drugs》2020,18(12)
Marine organisms and their associated microbes are rich in diverse chemical leads. With the development of marine biotechnology, a considerable number of research activities are focused on marine bacteria and fungi-derived bioactive compounds. Marine bacteria and fungi are ranked on the top of the hierarchy of all organisms, as they are responsible for producing a wide range of bioactive secondary metabolites with possible pharmaceutical applications. Thus, they have the potential to provide future drugs against challenging diseases, such as cancer, a range of viral diseases, malaria, and inflammation. This review aims at describing the literature on secondary metabolites that have been obtained from Scleractinian-associated organisms including bacteria, fungi, and zooxanthellae, with full coverage of the period from 1982 to 2020, as well as illustrating their biological activities and structure activity relationship (SAR). Moreover, all these compounds were filtered based on ADME analysis to determine their physicochemical properties, and 15 compounds were selected. The selected compounds were virtually investigated for potential inhibition for SARS-CoV-2 targets using molecular docking studies. Promising potential results against SARS-CoV-2 RNA dependent RNA polymerase (RdRp) and methyltransferase (nsp16) are presented. 相似文献
106.
Ammar Khalil Mohamed Ahmed Luping Jiang Fang Wang Song Chen Xueyan Zhou Xiaona Pei Xiyang Zhao Guanzheng Qu 《林业研究》2020,31(1):45-55
To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,and potassium fertilizers),each with four levels,using an orthogonal experimental design.A logistic model was used to estimate growth in height.The growth curves for tree height were sigmoid,and the model R^2 values were greater than 0.9,which indicated that the fit was highly significant.ANOVA results for tree height and basal diameter indicated that all sources of variance showed significant differences(p<0.001).The average tree height and basal diameter for all the four clones under the different treatments ranged from 155.39 to 235.04 cm,and from 13.71 to 17.42 mm,respectively.A highly positive correlation between the extreme k value and tree height was observed,suggesting that the k value was an accurate estimation of tree height.For model parameters,the earliest average time point for the onset of the rapid growth period of poplar clones was 131 d,and the highest average increment in tree height during the rapid growth period was 138.78 cm.The highest average tree height for all clones under each factor was 219,210.51,200,and 201 cm when treated with either 1200 mL of water applied every third day,3 g of nitrogen,0 g of phosphorus,or 0 g of potassium,respectively.The most suitable treatment for the early growth of hybrid poplar cuttings,as suggested by the developed logistic model,was 1200 mL of water applied every third day and three applications of 1 g nitrogen(in the form of CH4N2O). 相似文献
107.
Jeffers LA Shen H Khalil S Bissinger BW Brandt A Gunnoe TB Roe RM 《Pest management science》2012,68(1):49-59
BACKGROUND: Trypsin modulating oostatic factor (TMOF), a decapeptide (Tyr-Asp-Pro-Ala-Pro6) isolated from the ovaries of the adult yellow fever mosquito, Aedes aegypti, regulates trypsin biosynthesis. TMOF per os is insecticidal to larval mosquitoes and a good model for the development of technologies to enhance protein insecticide activity by reduced catabolism and/or enhanced delivery to the target. RESULTS: TFA-TMOF-K (TFA = trifluoro acetyl) allowed the specific conjugation of monodispersed, aliphatic polyethylene glycol (PEG) to the amino group of lysine-producing TMOF-K-methyl(ethyleneglycol)7-O-propionyl (TMOF-K-PEG7P). The addition of lysine to TMOF reduced its per os larval mosquitocidal activity relative to the parent TMOF, but conjugation of TMOF-K with methyl(ethyleneglycol)7-O-propionyl increased its toxicity 5.8- and 10.1-fold above that of TMOF and TMOF-K for Ae. aegypti. Enhanced insecticidal activity was also found for larval Ae. albopictus and for neonates of Heliothis virescens and Heliocoverpa zea. Only TMOF-K was found by MS/MS in the hemolymph for H. virescens fed on TMOF-K-PEG7P. No TMOF, TMOF-K or PEGylated TMOF-K was detected in the hemolymph after topical applications. CONCLUSIONS: This research suggests that aliphatic PEG polymers can be used as a new method for increasing the activity of insecticidal proteins. Copyright © 2011 Society of Chemical Industry 相似文献
108.
Khalil Zaynali Nezhad W. E. Weber M. S. Röder S. Sharma U. Lohwasser R. C. Meyer B. Saal A. Börner 《Euphytica》2012,186(1):127-138
Grain yield under post-anthesis drought stress is one of the most complex traits, which is inherited quantitatively. The present study was conducted to identify genes determining post-anthesis drought stress tolerance in bread wheat through Quantitative Trait Loci (QTLs) analysis. Two cultivated bread wheat accessions were selected as parental lines. Population phenotyping was carried out on 133 F2:3 families. Two field experiments and two experiments in the greenhouse were conducted at IPK-Gatersleben, Germany with control and post-anthesis stress conditions in each experiment. Thousand-grain weight was recorded as the main wheat yield component, which is reduced by post-anthesis drought stress. Chemical desiccation was applied in three experiments as simulator of post-anthesis drought stress whereas water stress was applied in one greenhouse experiment. Analysis of variance showed significant differences among the F2:3 families. The molecular genetic linkage map including 293 marker loci associated to 19 wheat chromosomes was applied for QTL analysis. The present study revealed four and six QTLs for thousand-grain weight under control and stress conditions, respectively. Only one QTL on chromosome 4BL was common for both conditions. Five QTLs on chromosomes 1AL, 4AL, 7AS, and 7DS were found to be specific to the stress condition. Both parents contributed alleles for drought tolerance. Taking the known reciprocal translocation of chromosomes 4AL/7BS into account, the importance of the short arms of homoeologous group 7 is confirmed for drought stress. 相似文献
109.
110.
Bahram Falahatkar Khalil Eslamloo Saichiro Yokoyama 《Journal of the World Aquaculture Society》2014,45(6):699-708
A study was performed to investigate the influence of dietary lactoferrin (LF) on growth and stress responses of juvenile Siberian sturgeon. Fish were fed six experimental diets (0, 100, 200, 400, 800, and 1600 mg LF/kg diet) for 10 wk. At the end of the experiment, fish were exposed to an acute stressor of 2‐min air exposure. The levels of cortisol, glucose, and lactate were measured before and at 1, 3, 6, 9, 12, and 24 h after stress. LF supplementation did not influence the fish growth. Cortisol and lactate, but not glucose level, were significantly affected by dietary LF. Cortisol levels in the control group rose twofold 1 h after stress and were significantly higher than that in LF groups. Moreover, the lowest level of cortisol at all sampling times (prestress and poststress) was observed in fish fed 400 mg LF/kg diet. Lactate concentrations in sturgeon fed 400 mg LF/kg markedly rose 1 h after stress, albeit changes in other LF groups were not significant. Results of this study show that dietary LF can suppress the stress responses in Siberian sturgeon, while 400 mg LF/kg diet appears to be an effective dietary level for this species to reduce stress. 相似文献