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1.
Canine parvovirus type 2 (CPV-2) causes a highly contagious gastroenteritis disease of dogs and wild canids. To investigate the CPV-2 prevalence in Dakahlia Governorate, Egypt, a total of 50 fecal swabs were collected from suspected diseased dogs during 2016–2017. Out of 50 collected samples, 35 samples (70 %) presented positive results for CPV-2 using immuno-chromatography (IC) as a rapid test. CPV-2DNA was detected in 42 samples (84 %) by using polymerase chain reaction (PCR). The frequencies of CPV-2 were significantly higher in German shepherd breed (46 %; 23/50) and in age groups less than 6 months (76%; 38/50). We evaluated the breed, age, sex, rapid test results and clinical signs as predictors for classification of animal status into infected and not infected. The best predictors for classification process were rapid test result and clinical signs. Both CPV-2b and CPV-2c subtypes were detected by CPV2-VP2 gene sequences analysis. Deduced amino acid sequences alignment showed substitutions at 3 sites (Arg453Pro, Ala574Glu and Gln457Leu). Further investigations are needed to reveal the genetic and antigenic relation between field and vaccinal strains of CPV-2 in Egypt.  相似文献   
2.
The employment of formulateBacillus subtilis as a biocontrol agent successfully controlledFusarium oxysporum f.sp.lycopersici within tomato seedlings (in vivo). B. subtilis was able to proted cortex and vascular tissues of tomato against progression of the wilt pathogen. No changes were observed in tomato tissues due to application ofB. subtilis except for hypertrophy and elongation of cortex tissues, which indicates the production of plant growth hormones byB. subtilis.  相似文献   
3.
The hemispherical soft scale, Saissetia coffeae (Walker) (Homoptera: Coccidae), is one of the most important pests attacking olive trees in Egypt. During the period 2001–2003, a total of about 300,000 individuals of the parasitoid Coccophagus cowperi Girault (Hymenoptera: Aphelinidae), obtained from India, was released at 35 sites for the biological control of S.coffeae on olive trees in Egypt. The maximum parasitism rates reached 53 and 62%, while average parasitism rates were 17.2 and 30.8% in the Marsy Mattrouh and El-Arish locations, respectively. These results indicate establishment of this parasitoid on this important economic plant in Egypt.  相似文献   
4.
李红云  田明 《安徽农业科学》2014,42(36):13167-13169
托勒密埃及(公元前305~公元前30年)是古代埃及农业经济发展史上的一个繁荣时期,它创造和奠定了古代埃及成为地中海世界经济粮仓地位的坚实基础.这种农业经济的发展主要是在希腊文化到来后,统治者在立足现实情况的基础上,选择了一条将两种文化融合发展的道路,促使古代埃及在政治上,在农业发展上和经济管理模式上,以及技术应用与改良上都发生了极大变化,从而显著地促进了托勒密王朝时期埃及农业经济的发展.  相似文献   
5.
Aim and Background  Little data are available on the levels of polycyclic aromatic hydrocarbons (PAHs) in the sediments of the Mediterranean Sea Coast of Egypt in general and the Alexandria coastal zone in particular. It was therefore deemed necessary to set up a monitoring programme to determine the current concentrations of PAHs in bottom sediments, and to identify any area where high concentrations of these potential hazardous contaminants were present in the Western Harbour of Alexandria. Methods  The composition, distribution and the source of PAHs in surficial sediments of the harbour were investigated. To document the spatial PAH input, surficial sediment samples from 23 locations throughout the harbour were analysed. as]Results and Discussion The total PAH load determined in the surficial sediment samples ranged from 8 to 131150 ng g1 dry wt, generally with most of the samples having total concentrations of PAHs greater than 5000 ng g1 dry weight. The highest concentration of total PAHs was recorded in sediments of the inner harbour. Ratio values of specific compounds such as phenanthrene to anthracene, fluoranthrene to pyrene, methyl-phen-anthrene to phenanthrene, methyl-dibenzothiophenes to dibenzothiophenes, alkylated to non-alkylated and high molecular weight to low molecular weight PAH, were calculated to evaluate the possible source of PAH contamination in the harbour sediments. Conclusions  Two main sources of PAH in the study area have been found: pyrolytic and petrogenic. Interferences of rather petrogenic and pyrolytic PAH contaminations were noticed for most samples. The dominant sources of PAH appear to be the combustion processes through run-off, industrial and sewage discharges, and atmospheric input. The concentrations of PAHs were generally above levels expected to cause adverse biological effects. Recommendations and outlook  Information from this study and any other relevant studies should be useful in designing future strategies for environmental protection and management of the harbour.  相似文献   
6.
The objective of the present study was to describe the prevalence and risk factors associated with cryptosporidiosis in buffalo calves in Middle Egypt. During one year, 458 fecal samples were collected from buffalo calves less than 3 month age in 55 small scale herds and examined for the presence of Cryptosporidium oocysts. Data describing age, gender, season, and herd management practices were gathered to assess potential risk factors. Fecal examination showed that 14.19% of the examined calves were positive for Cryptosporidium spp. Calves at 1-15 days were at the highest risk (P < 0.001), and a significant relationship between season and infection (P < 0.05) was recorded. A significant association between infection and hygiene (P < 0.001), type of floor (P < 0.01) and source of water (P < 0.01) was also recorded. Statistical analysis concerning the clinical signs and fecal characteristics revealed a significant association with fecal consistency (P < 0.001), presence of blood (P < 0.01) and mucous (P < 0.01). Moreover, a significant association was found between infection and the desire for suckling (P < 0.05) and tenesmus (P < 0.05). The results of the present study demonstrated the strong relation between infections by Cryptosporidium spp. and diarrhea in buffalo calves.  相似文献   
7.
ABSTRACT

1. Avipoxvirus (APV) infections are one of many threats inflicting economic losses within the poultry industry, particularly in tropical and subtropical countries. A proper and comprehensive study for APVs is needed to increase the knowledge concerning the diversity and evolution of the virus.

2. For this purpose, 136 bird flocks of different species and breeding types were examined for APV infection between October 2016 and November 2017. One hundred and thirty samples had visible pocks on the chorioallantoic membrane (CAM) which were designated as fowl pox-like viruses via amplification of 578 bp from the P4b gene and 1800 bp from the fpv140 locus.

4. A comprehensive phylogenetic analysis of fpv167 locus (P4b), fpv140 locus (fpv139 and fpv140) and fpv94 (DNA polymerase) revealed that all the analysed strains belong to fowl pox-like viruses (clade A; subclade A1 and A2). Based on the fpv140 locus full nucleotide sequence, three turkey originated strains were seen to be divergent from chicken originated sequences and branched into novel subclade A1.b.

5. Trees comparison, within the term of speculation of virus-host specificity, clearly highlighted a high order specific subgrouping among subclades in the case of the fpv140 locus (including fpv139 and fpv140). Hence, the fowl poxvirus, turkey poxvirus and pigeon poxvirus strains clustered into distinct host-specific subclades A1a, A1.b and A2, respectively, which could not be seen in the FWPV-P4b and DNA polymerase phylogeny.  相似文献   
8.
9.
The aim of the present study was to carry out molecular epidemiological investigation on enterotoxigenic Escherichia coli (ETEC) K99 and Salmonella spp. in diarrheic neonatal calves. Fecal samples were obtained from 220 diarrheic calves at 9 farms related to four governorates in central and northern Egypt. E. coli and Salmonella spp. isolates were examined for E. coli K99 and Salmonella spp. using PCR. ETEC K99 was recovered from 20 (10.36 %) out of 193 isolates, whereas Salmonella spp. was recovered from nine calves (4.09%).Multivariable logistic regression was used to evaluate the risk factors associated with both infections. ETEC K99 was significantly affected by age (P < 0.01; OR: 1.812; CI 95%: 0.566–1.769), colostrum feeding practice (P < 0.01; OR: 5.525; CI 95%: 2.025–15.076), rotavirus infection (P < 0.001; OR: 2.220; CI 95%: 0.273–1.251), vaccination of pregnant dams with combined vaccine against rotavirus, coronavirus and E. coli (K99) (P < 0.001; OR: 4.753; CI 95%: 2.124–10.641), and vitamin E and selenium administration to the pregnant dam (P < 0.01; OR: 3.933; CI 95%: 0.703–1.248).Infection with Salmonella spp. was found to be significantly affected by the animal age (P < 0.05; OR: 0.376; CI 95%: 0.511–1.369), Hygiene (P < 0.05; OR: 0.628; CI 95%: 1.729–5.612), and region (P < 0. 01; OR: 0.970; CI 95%: 0.841–1.624).The results of the present study indicate the importance of PCR as rapid, effective and reliable tool for screening of ETEC and Salmonella spp. when confronted with cases of undifferentiated calf diarrhea. Moreover, identification of the risk factors associated with the spreading of bacteria causing diarrhea may be helpful for construction of suitable methods for prevention and control.  相似文献   
10.

Sampling theory was combined with resampling techniques to determine the number of location-years needed for estimating an insect's required thermal summation and lower developmental threshold from field-based studies. This was done by analysing 19 location-years of field observations on the first emergence of Apthona nigriscutis Foudras, an important biological control agent of the noxious weed, leafy spurge (Euphorbia esula L.). Results indicated that 5 - 7 location-years were needed to estimate that insect's mean required thermal summation and mean lower developmental threshold for predicting first adult emergence. However, if the wish was to estimate the median required thermal summation and median lower developmental threshold for that purpose, then 8 - 11 location-years were needed to obtain acceptable estimates of those parameters. The implications of these and other findings are discussed.  相似文献   
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