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排序方式: 共有309条查询结果,搜索用时 156 毫秒
301.
Mandana Salehi Ahmad Majd Parissa Jonoubi Leila Karami Gholamali Kardar Zahra Pourpak 《Aerobiologia》2014,30(1):59-69
In Bushehr province of Iran, Avicennia marina trees have grown in Bordekhoon (Mond Protected Area) and Assaluyeh (Marine National Park of Nayband). Contrary to Bordekhoon, Assaluyeh is a petrochemical region with environmental pollution. This study was aimed to studying protein profiles, allergenic bands, ontogeny, structure and elemental composition of tectum of A. marina pollens in Assaluyeh and Bordekhoon. Pollens were collected from two regions and extracted in PBS, and protein profiles of pollens were determined by sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). As an experimental model, 20 female 6–8-week-old Balb/C mice were divided into two groups. The mice of first and second groups were sensitized by Bordekhoon and Assaluyeh pollen extracts, respectively, and mice serum samples were used for immunoblotting. Pollen characteristics were studied using light and scanning electron microscopes. SDS-PAGE showed some differences between pollen protein profiles of two regions. Immunoblotting assay detected that pollens have two allergenic bands and the protein band at 100 KD is the common allergenic protein in two regions. Light microscopy revealed that the development of anther wall was basic type and some abnormalities were observed in microspores and pollens of Assaluyeh. Scanning electron microscopy studies showed that the apertures in considerable numbers of Assaluyeh pollens were closed. The comparison of elemental composition of pollen tectum between two regions showed that pollens of Assaluyeh have accumulated Cu on their tectum. Results obtained indicated that environmental pollution can affect protein profile, allergenic bands, structure and elemental composition of tectum of A. marina pollens. 相似文献
302.
Growth performance and carcass quality of fattening lambs from fat-tailed and tailed sheep breeds 总被引:1,自引:0,他引:1
The growth performance and carcass traits of two fat-tailed breeds (Chaal and Zandi) and their crosses with rams of a tailed breed (Zel) were compared. After weaning, the growth and feed consumption of male and female lambs fattened for 114 days were recorded. A total of 45 male and female lambs were slaughtered and the left side of the carcasses were cut into six pieces, and the lean meat, bone, subcutaneous and intermuscular fat were determined. Average daily gain and feed conversion ratio in crossbred lambs improved, but the differences with pure lambs were not significant. The average weight of shoulder, brisket and loin were higher in crossbred than pure breed lambs (P < 0.01). The percentage of protein in the carcass of Zel × Zandi lambs was significantly higher than Zandi lambs. The smaller size and lower weight of fat-tail in crossbred lambs were compensated by higher percentage of subcutaneous, intermuscular and internal fat. The fat-tailed breeds provided good quality lean meat in terms of lower percentage of intermuscular fat. 相似文献
303.
A. Derakhshandeh T. Zahraei Salehi H. Tadjbakhsh V. Karimi 《Letters in applied microbiology》2009,49(3):403-407
Aims: To identify, clone and sequence the iss (increased serum survival) gene from E. coli strain χ1378 isolated from Iranian poultry and to predict its protein product, Iss.
Methods and Results: The iss gene from E. coli strain χ1378 was amplified and cloned into the pTZ57R/T vector and sequenced. From the DNA sequence, the Iss predictive protein was evaluated using bioinformatics. Iss from strain χ1378 had 100% identity with other E. coli serotypes and isolates from different origins and also 98% identity with E. coli O157:H7 Iss protein. Phylogenetic analysis showed no significant different phylogenic groups among E. coli strains.
Conclusions: The strong association of predicted Iss protein among different E. coli strains suggests that it could be a good antigen to control and detect avian pathogenic E. coli (APEC).
Significance and Impact of the study: Because the exact pathogenesis and the role of virulence factors are unknown, the Iss protein could be used as a target for vaccination in the future, but further research is required. 相似文献
Methods and Results: The iss gene from E. coli strain χ1378 was amplified and cloned into the pTZ57R/T vector and sequenced. From the DNA sequence, the Iss predictive protein was evaluated using bioinformatics. Iss from strain χ1378 had 100% identity with other E. coli serotypes and isolates from different origins and also 98% identity with E. coli O157:H7 Iss protein. Phylogenetic analysis showed no significant different phylogenic groups among E. coli strains.
Conclusions: The strong association of predicted Iss protein among different E. coli strains suggests that it could be a good antigen to control and detect avian pathogenic E. coli (APEC).
Significance and Impact of the study: Because the exact pathogenesis and the role of virulence factors are unknown, the Iss protein could be used as a target for vaccination in the future, but further research is required. 相似文献
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Sara Hosseini Samaneh Hosseini Mohammad Salehi 《Journal of cellular physiology》2020,235(12):9752-9762
Despite encouraging advances in fertility technology, the success rate of an ongoing pregnancy is relatively low and predominantly associated with implantation failure. Inflammatory responses are beneficial in the fetomaternal interface and supposedly accelerate the chances for successful implantation. The current study aims to determine the effect of Toll-like receptor 4 (TLR4) overexpression in mouse blastocysts via Let-7a downregulation using intracytoplasmic sperm injection-sperm-mediated gene transfer on embryo attachment rate. The pLenti-III-GFP-miR-Off-Let-7a vector was transmitted to oocytes derived via in vitro maturation (IVM) and in vivo oocytes by using NaOH-treated spermatozoa. Let-7a and TLR4 expression levels were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), immunocytochemistry, and western blot analysis in both oocytes and embryos. Blastocyst adhesion on the endometrial cells was monitored by microscopic analysis. qRT-PCR results showed that Let-7a expression decreased in the IVM (GV-MII) oocytes compared to the in vivo oocyte (MII) group (p < .05). TLR4 showed a higher expression in GV-MII oocytes at both the gene and protein levels (p < .05). Following anti-miR-Let-7a transmission, the TLR4 expression level was significantly upregulated in embryos compared with the control groups (p < .05). Attachment and migration of trophoblasts cells towards endometrial cells dramatically increased compared to the control group (p < .05). Based on our results, we concluded that Let-7a might mediate embryo attachment through regulation of TLR4 expression levels. 相似文献
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