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11.

Background:

Among the eight known human herpes viruses, Epstein- Barr virus (EBV) is considered to be sexually transmissible. This study was conducted to evaluate the seroepidemiology of this infection in married and unmarried Iranian couples.

Methods:

In this comparative observational and cross-sectional study, 160 men and women were divided into married and unmarried groups. Serum IgG and IgM antibodies to the EBV viral capsid antigen were analyzed by Enzyme-linked Immunosorbent Assays (ELISAs).

Results:

In this study 78 men and 82 women were enrolled. Ninety percent of the married and 76.2% of the unmarried women were anti-EBV IgG positive (P = 0.08), while 80% of the married and 94% of the unmarried men were antiEBV IgG positive (P = 0.052).

Conclusion:

Seroepidemiology of EBV is not significantly different in married vs. unmarried women and men in Iran; therefore, sexual contact may not be the primary mechanism of EBV transmission in Iran and other developing countries. Attention to other possible routes of transmission is recommended. Key Words: Epstein Barr Virus, Sexual contact, Anti-VCA  相似文献   
12.
The biotransformation of several monoterpenes by the locally isolated unicellular microalga, Oocystis pusilla was investigated. The metabolites were identified by thin layer chromatography and GC/MS. The results showed that O. pusilla had the ability to reduce the C=C double bond in (+)-carvone to yield trans-dihydrocarvone and traces of cis-dihydrocarvone. O. pusilla also converted (+)-limonene to trans-carveol, as the main product, and yielded carvone and trans-limonene oxide. Furthermore, (−)-linalool was converted to trans-furanoid and trans-pyranoid linalool oxide, thymol was converted to thymoquinone, (−)-carveol was converted to carvone and trans-dihydrocarvone, (−)-menthone and (+)-pulegone were converted to menthol, (L)-citronellal was converted to citronellol, and (+)-β-pinene was converted to trans-pinocarveol.  相似文献   
13.
A unicellular cyanobacterium,Chroococcus dispersus (Keissl.) Lemmermann, was isolated from paddy-field and tested in biotransformation experiments of hydrocortisone (compound 1). This strain has not been previously examined for steroid substance modification. Fermentation was carried out in BG-11 medium supplemented with 0.05% substrate at 25 °C for seven days incubation. The metabolites were chromatographically purified and characterised using spectroscopic methods. The fermentation yielded 11β,17α,20β,21-tetrahydroxypregn-4-en-3-one (compound 2), 11β,17β-dihydroxyandrost-4-en-3,17-dione (compound 3), and 11β-hydroxyandrost-4-en-3,17-dione (compound 4). Bioreaction characteristics observed were 20-ketone reduction for accumulation of compound 2 and side chain degradation of the substrate to give compounds 3 and 4. Time course study showed the accumulation of the product 2 from the second day of the fermentation and product 3 as well as product 4 from the third day. All the metabolites reached their maximum concentration in seven days. Aeration and continuous light or light duration (16/8 hours light/dark) have no effect on the transformation yield. Optimum concentration of the substrate, which gave maximum bioconversion efficiency, was 0.5 mg ml?1 in the transformation experiment. Growth was not influenced by the addition of steroid substrate. Biotransformation was completely inhibited when steroid concentration was above 2.0 mg ml?1.  相似文献   
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The aim of this research was a comparative study on the isolation and culture of head kidney macrophages derived from Acipenser persicous and Rutilus frisii kutum as teleost and chondrostei species of fish. The macrophages were isolated by density gradient sedimentation, followed by adherence to a plastic surface. They exhibited strong phagocytic activity against bacteria. The effect of cell density, incubation time, FBS percentage, pH and temperatures on the cell number and viability were determined and compared. Also, the effect of light/dark regimen on viability, adherence, release of reactive oxygen species (ROS) and nitric oxide (NO) in the macrophages was determined. The results showed that the Caspian kutum macrophages were more sensitive to FBS percentage and cell density whereas the Persian sturgeon macrophages were more sensitive to pH of the cell culture media. The adherence and viability of the macrophages from both fish species firstly increased (P?<?0.05) after exposure to a light/dark regimen, but then significantly decreased as did ROS and NO productions. For the first time, this study has determined the optimal conditions for primary culture of macrophages derived from sturgeons, and shows the unique effect of light on the biology of fish immune cells.  相似文献   
16.
Using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), simple sequence repeats (SSR), and morphological traits, the first genetic maps for Cucurbita pepo (2n=2x=40) were constructed and compared. The two mapping populations consisted of 92 F2 individuals each. One map was developed from a cross between an oil-seed pumpkin breeding line and a zucchini accession, into which genes for resistance to Zucchini Yellow Mosaic Virus (ZYMV) from a related species, C. moschata, had been introgressed. The other map was developed from a cross between an oil-seed pumpkin and a crookneck variety. A total of 332 and 323 markers were mapped in the two populations. Markers were distributed in each map over 21 linkage groups and covered an average of 2,200 cM of the C. pepo genome. The two maps had 62 loci in common, which enabled identification of 14 homologous linkage groups. Polyacrylamide gel analyses allowed detection of a high number of markers suitable for mapping, 10% of which were co-dominant RAPD loci. In the Pumpkin-Zucchini population, bulked segregant analysis (BSA) identified seven markers less than 7 cM distant from the locus n, affecting lignification of the seed coat. One of these markers, linked to the recessive hull-less allele (AW11-420), was also found in the Pumpkin-Crookneck population, 4 cM from n. In the Pumpkin-Zucchini population, 24 RAPD markers, previously introduced into C. pepo from C. moschata, were mapped in two linkage groups (13 and 11 markers in LGpz1 and LGpz2, respectively), together with two sequence characterized amplified region (SCAR) markers linked to genes for resistance to ZYMV.  相似文献   
17.
A method named "bag culture" was developed for coculturing of Linum persicum (section Syllinum) and L. austriacum (section Linum) hairy roots. For this propose L. austriacum and L. persicum hairy root cultures were established using Agrobacterium rhizogenes in McCown medium. L. persicum hairy roots in bags (1 mm2 mesh) were successfully grown together with L. austriacum hairy roots. The amounts of podophyllotoxin (PTOX) and 6-methoxypodophyllotoxin (MPTOX) produced by L. persicum hairy root cultures were detected using HPLC. The results indicated that the amounts of both lignans and growth indexes of the two hairy roots decreased, that may be partly due to a competition between the two types of culture in using precursors of biosynthetic metabolites and the amount of culture medium which is available for each hairy root. However, MPTOX (0.17 g/100 g DW) and PTOX (0.02 g/100 g DW) levels of the L. persicum single culture in bag were significantly higher than of the other cultures which may be due to the immobilization effect of the bag.  相似文献   
18.
ISSR markers were applied to evaluate the genetic diversity and differentiation of 270 individuals of 27 Iranian C. melo landraces of various varietal groups include vars. inodorous, cantalupensis, reticulatus, ameri, dudaim. Genetic diversity among the studied genotypes obtained by GeneAlex analysis (H?=?0.08, I?=?0.12, Na?=?0.77, PPL?=?22.6%). Cluster analysis divided Iranian melon landraces into two main cluster. Non-sweet genotype (dudaim group) was well separated from sweet genotypes (inodorous, ameri, reticulatus, cantalupensis). The most similar genotypes were BANI and TONI (0.95) and the most dissimilar ones were GER and TS (0.58). AMOVA result showed that the percentage of genetic variation among and within Iranian melon is 69% and 31%, respectively. All landraces evaluated based on 10 morphological traits which revealed the diversity of melon varietal groups. Bayesian analysis assigned ten landraces to Pop 1, eight landraces to Pop 2 and nine melon landraces to Pop 3. Bayesian and UPGMA cluster analyses demonstrated the almost related results. Our results indicated that ISSR markers technique alongside polyacrylamide gel analysis could be helpful to discriminate varieties of melon.  相似文献   
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