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101.
This paper report on a new species of mites of the genus Myrmozercon associated with ant in Iran – Myrmozercon cyrusi Ghafarian and Joharchi sp. n. was collected associated of the Monomorium sp. in Kenevist Rural District in the Central District of Mashhad County, Khorasan Razavi Province, Iran. This new species is described and illustrations provided. Myrmozercon ovatum Karawajew, 1909 is suspected to be a junior synonym of Myrmozercon brevipes Berlese, 1902 and host-specificity and host range of Myrmozercon are also reviewed.  相似文献   
102.
Many of CNS diseases can lead to a great quantity of release of glutamate and the extreme glutamate induces neuronal cell damage and death. Here, we wanted to investigate the effects of Cymbopogon citratus essential oil and Ferula assa-foetida extracts treatment on glutamate-induced cell damage in a primary culture of rat cerebellar granule neurons. Cerebellums were collected from 7-d rat brains and cerebellar granule neurons were obtained after 8-d culture. CGN cells were treated with C. citratus essential oil and F. assa-foetida extracts at concentration of 100 μg/ml before, after, and during exposure to 30 μM glutamate. The cellular viability was evaluated by 3-(4, 5-dimethytthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide (MTT) staining. The flow cytometry assay was used to examine cell cycle and apoptosis. MTT assay showed a glutamate-induced reduction in cellular viability while treatment with C. citratus essential oil and F. assa-foetida extracts before, during, and after exposure to glutamate was increased. Flow cytometric analysis indicated that F. assa-foetida extracts treatment significantly (p?<?0.001) attenuated glutamate-induced apoptotic/necrotic cell death and the necrotic rate was decreased by C. citratus essential oil treatment compared to glutamate group, significantly (p?<?0.001). The results show that C. citratus essential oil and F. assa-foetida extracts display neuroprotective effects in glutamate-induced neurotoxicity. These extracts exert antiapoptotic activity in cerebellar granule neurons due to cell cycle arrest in G0G1 phase, which explain the beneficial effects of C. citratus essential oil and F. assa-foetida extracts as therapies for neurologic disorders.  相似文献   
103.
Host genetic variation plays an important role in the structure and function of heritable microbial communities. Recent studies have shown that insects use immune mechanisms to regulate heritable symbionts. Here we test the hypothesis that variation in symbiont density among hosts is linked to intraspecific differences in the immune response to harboring symbionts. We show that pea aphids (Acyrthosiphon pisum) harboring the bacterial endosymbiont Regiella insecticola (but not all other species of symbionts) downregulate expression of key immune genes. We then functionally link immune expression with symbiont density using RNAi. The pea aphid species complex is comprised of multiple reproductively-isolated host plant-adapted populations. These ‘biotypes’ have distinct patterns of symbiont infections: for example, aphids from the Trifolium biotype are strongly associated with Regiella. Using RNAseq, we compare patterns of gene expression in response to Regiella in aphid genotypes from multiple biotypes, and we show that Trifolium aphids experience no downregulation of immune gene expression while hosting Regiella and harbor symbionts at lower densities. Using F1 hybrids between two biotypes, we find that symbiont density and immune gene expression are both intermediate in hybrids. We propose that in this system, Regiella symbionts are suppressing aphid immune mechanisms to increase their density, but that some hosts have adapted to prevent immune suppression in order to control symbiont numbers. This work therefore suggests that antagonistic coevolution can play a role in host-microbe interactions even when symbionts are transmitted vertically and provide a clear benefit to their hosts. The specific immune mechanisms that we find are downregulated in the presence of Regiella have been previously shown to combat pathogens in aphids, and thus this work also highlights the immune system’s complex dual role in interacting with both beneficial and harmful microbes.  相似文献   
104.
PrP genotypes at codons 136 and 171 in 120 Iranian Ghezel sheep breeds were studied using allele-specific PCR amplification and compared with the well-known sheep breeds in North America, the United States and Europe. The frequency of V allele and VV genotype at codon 136 of Ghezel sheep breed was significantly lower than AA and AV. At codon 171, the frequency of allele H was significantly lower than Q and R. Despite the similarities of PrP genotypes at codons 136 and 171 between Iranian Ghezel sheep breeds and some of the studied breeds, significant differences were found with others. Planning of effective breeding control and successful eradication of susceptible genotypes in Iranian Ghezel sheep breeds will not be possible unless the susceptibility of various genotypes in Ghezel sheep breeds to natural or experimental scrapie has been elucidated.Key words: scrapie, Ghezel sheep breed, PrP genotyping, allele specific amplification, codon 136, codon 171Scrapie was first described in England in 1732,1 and it is an infectious neurodegenerative fatal disease of sheep and goats belonging to the group of transmissible subacute spongiform encephalopathies (TSEs), along with bovine spongiform encephalopathy (BSE), chronic wasting disease and Creutzfeldt-Jakob disease.2,3 The term prion, proteinaceous infectious particles, coined by Stanley B. Prusiner, was introduced, and he presents the idea that the causal agent is a protein.4 Prion proteins are discovered in two forms, the wild-type form (PrPc) and the mutant form (PrPSc).5 Although scrapie is an infectious disease, the susceptibility of sheep is influenced by genotypes of the prion protein (PrP) gene.2,6 Researchers have found that the PrP allelic variant alanine/arginine/arginine (ARR) at codons 136, 154 and 171 is associated with resistance to scrapie in several breeds.714 Most of the sheep populations in the Near East and North African Region (84% of the total population of 255 million) are raised in Iran, Turkey, Pakistan, Sudan, Algeria, Morocco, Afghanistan, Syria and Somalia.15 In 2003, the Iranian sheep population was estimated at 54,000,000 head. The Ghezel sheep breed, which also is known as Kizil-Karaman, Mor-Karaman, Dugli, Erzurum, Chacra, Chagra, Chakra, Gesel, Gezel, Kazil, Khezel, Khizel, Kizil, Qezel, Qizil and Turkish Brown, originated in northwestern Iran and northeastern Turkey. By considering sheep breeds as one of the main sources of meat, dairy products and related products, a global screening attempt is started in different areas. In compliance with European Union Decision 2003/100/EC, each member state has introduced a breeding program to select for resistance to TSEs in sheep populations to increase the frequency of the ARR allele. A similar breeding program is established in United States and Canada. The Near East and North African Region still needs additional programs to help the global plan of eradication of scrapie-susceptible genotypes. The current study was the first to assess the geographical and molecular variation of codons 136 and 171 polymorphism between Iranian Ghezel sheep breed and well-known sheep breeds.Polymorphism at codon 136 is associated with susceptibility to scrapie in both experimental and natural models.10,11,13,16 17 and Austrian Carynthian sheep.18 Swiss White Alpine showed higher frequency of allele V at position 136 than Swiss Oxford Down, Swiss Black-Brown Mountain and Valais Blacknose.19 Comparison of polymorphism at codon 136 in the current study with some of other breeds (20 some flock of Hampshire sheep21 with current study, but the frequency of it is higher than that of some other breeds.

Table 1

Comparison of PrP allelic and genotype frequencies at codon 136 in different breeds
BreedA (%)V (%)AA (%)AV (%)VV (%)Reference
Iranian Ghezel breeds (n = 120)77.5022.565.0025.0010.00Current study
Oklahoma sheep (n = 334)De Silva, et al.27
Suffolk99.240.7698.481.520.00
Hampshire1000.001000.000.00
Dorset92.67.9487.309.523.17
Montadale77.6622.3459.5736.174.26
Hampshire (n = 48)93.756.2588.0012.000.00Youngs, et al.21
German Sheep Breeds (n = 660)92.897.1187.8010.471.73Kutzer, et al.28
Bleu du Maine83.4716.5369.5627.832.61
Friesian Milk S.1000.001000.000.00
Nolana90.139.8785.908.465.64
Suffolk1000.001000.000.00
Texel90.879.1382.1617.410.43
Swiss Sheep (n = 200)92.57.5Gmur, et al.19
Swiss Oxford Down93.007.00---
Swiss Black-Brown M.99.001.00---
Valais Blacknose1000.00---
Swiss White Alpine88.0022.00---
Austrian Sheep (n = 112)98.951.0598.950.001.05Sipos, et al.18
Tyrolean mountain sheep1000.001000.000.00
Forest sheep1000.001000.000.00
Tyrolean stone sheep1000.001000.000.00
Carynthian sheep95.804.2095.800.004.20
Open in a separate windowIt has been found that a polymorphism at codon 171 also is associated with susceptibility to experimental scrapie in Cheviot sheep16 and natural scrapie in Suffolk sheep.22 As shown in 23 They also found that different breeds show different predominant genotypes in ewes and rams.23 Different PrP genotypes were found at codon 171 in Austrian sheep breeds, but QQ has higher frequency than others.18 In some kinds of Swiss breeds, allelic frequencies of allele Q was higher than R.19 Distribution of prion protein codon 171 genotypes in Hampshire sheep revealed that different flocks shows different patterns.21 The frequency of PrP genotypes at codon 171 in Iranian Ghezel breeds was similar to some sheep breeds, like the Suffolk breed of Oklahoma sheep, but it was completely different from others (
PrP genotypes at codon 172
BreedAllelic frequencyGenotypesReference
QRHRRQRQQQHRHHH
Iranian Iranian Ghezel breeds (n = 120)55.0043.331.6723.3336.6736.670.003.330.00Current study
Oklahoma sheep (n = 334)De Silva, et al.20
Suffolk40.9559.050.0037.0743.9718.970.000.000.00
Hampshire51.8948.110.0021.7052.8325.470.000.000.00
Dorset67.7531.250.007.9546.5945.450.000.000.00
Montadale62.9637.040.0014.8144.4440.740.000.000.00
Hampshire (n = 201)72.1426.601.265.0042.0050.002.001.000.00Youngs, et al.21
German Sheep Breeds (n = 660)Kutzer, et al.28
Bleu du Maine37.862.20.0046.9630.4422.60.000.000.00
Friesian Milk S.90.458.90.651.2715.382.80.000.000.64
Nolana42.357.80.0036.6242.2621.130.000.000.00
Suffolk68.427.64.016.121.8455.174.61.151.15
Texel55.3529.714.912.5626.8336.3611.257.365.63
Swiss Sheep (n = 200)Gmur, et al.19
Swiss Oxford Down32.0068.00-------
Swiss Black-Brown M.70.0030.00-------
Valais Blacknose85.0015.00-------
Swiss White Alpine27.0073.00-------
Austrian Sheep (n = 112)Sipos, et al.18
Tyrolean mountain sheep74.3025.800.002.9045.7051.400.000.000.00
Forest sheep77.0019.203.8011.5015.4069.200.000.003.80
Tyrolean stone sheep81.5014.803.700.0029.6062.907.400.000.00
Carynthian sheep72.8023.004.204.2041.7013.008.400.000.00
Open in a separate windowThe association between scrapie susceptibility and polymorphism at codon154 is unclear, and fewer evidences were found that support it.24,25 So the frequency of different genotypes at codon 154 in Iranian Sheep breeds has not been included in the current study.In addition to difference in number of included animals and methodology of genotyping, the apparent discrepancies among reported allelic frequency might be caused by the difference in geographical dissemination of sheep breeds and related purity.26 The deviations from Hardy-Weinberg equilibrium, which were assumed in the current study, were checked using Pearson''s chi-squared test or Fisher''s exact test. Although the number of animals in this study is acceptable, a population study is still suggested. In conclusion, fairly different patterns of PrP genotypes in this common Near eastern sheep breed are an evidence for geographical variation of molecular susceptibility to scrapie. Because other report from Turkey also has shown a prevalence of genotypes, which is different from western countries,26 and no reports have been published yet to show which of the genotypes in that breed are actually resistant or susceptible to natural or experimental scrapie, our results is an authentic platform to motivate further studies. Actually, extrapolation of the existing general pattern of susceptibility or resistance for all breeds and current plan of elimination would not be successful unless the susceptible genotypes in the Near East with numerous breeds will be identified. Hence, the current study could be used as an important pilot study for further investigation.Genomic DNA was isolated from fresh EDTA-treated blood of 120 healthy, randomly chosen sheep of Iranian Ghezel sheep breeds using a mammalian blood DNA isolation kit (Bioflux, Japan). The allelic frequencies of prion protein codons 171 and 136 were determined by allele-specific PCR amplifications using scrapie susceptibility test kit (Elchrom Scientific AG). Primer sets were designed by manufacturer to amplify specific gene targets according to possible genotypes of positions 136 and 171.The amplification reactions were performed using iCycler™ (BioRad Inc.,), and PCR products (PositionGenotypeFragment size136A133136V139171H170171Q247171R155Open in a separate window  相似文献   
105.
Proviral Integration Site for Moloney Murine Leukemia Virus (PIM) Kinases Promote Human T Helper 1 Cell Differentiation     
Johanna Tahvanainen  Minna K. Kyl?niemi  Kartiek Kanduri  Bhawna Gupta  Hanna L?hteenm?ki  Teemu Kallonen  Anna Rajavuori  Omid Rasool  P?ivi J. Koskinen  Kanury V. S. Rao  Harri L?hdesm?ki  Riitta Lahesmaa 《The Journal of biological chemistry》2013,288(5):3048-3058
The differentiation of human primary T helper 1 (Th1) cells from naïve precursor cells is regulated by a complex, interrelated signaling network. The identification of factors regulating the early steps of Th1 cell polarization can provide important insight in the development of therapeutics for many inflammatory and autoimmune diseases. The serine/threonine-specific proviral integration site for Moloney murine leukemia virus (PIM) kinases PIM1 and PIM2 have been implicated in the cytokine-dependent proliferation and survival of lymphocytes. We have established that the third member of this family, PIM3, is also expressed in human primary Th cells and identified a new function for the entire PIM kinase family in T lymphocytes. Although PIM kinases are expressed more in Th1 than Th2 cells, we demonstrate here that these kinases positively influence Th1 cell differentiation. Our RNA interference results from human primary Th cells also suggest that PIM kinases promote the production of IFNγ, the hallmark cytokine produced by Th1 cells. Consistent with this, they also seem to be important for the up-regulation of the critical Th1-driving factor, T box expressed in T cells (T-BET), and the IL-12/STAT4 signaling pathway during the early Th1 differentiation process. In summary, we have identified PIM kinases as new regulators of human primary Th1 cell differentiation, thus providing new insights into the mechanisms controlling the selective development of human Th cell subsets.  相似文献   
106.
Microfacies,sedimentary environment and paleoecology of Paleocene–Eocene deposits in the Zagros Basin,north of Shiraz,southwest Iran     
Mahnaz Parvaneh Nejad Shirazi  Mohammad Bahrami  Hassan Amiri Bakhtiar  Omid Bamdad 《Historical Biology》2013,25(4):493-501
The Jahrum Formation act as reservoir rocks in the Zagros Mountains west of Iran. For the study of this formation, a stratigraphic section of Lapoee which is situated north of Shiraz has been examined. Petrographic and stratigraphic results along with field observations show that the Jahrum Formation consists of cream-grey thin-to-medium-bedded limestone so that at the top of the formation, they are locally changed to dolomite. The Jahrum Formation overlies the Sachun Formation. We also found Nubecularids as paleoecology indicators in middle parts of the Jahrum Formation. The presence of Nubecularids in the Lapoee stratigraphic section (i.e. the Jahrum Formation) indicates a lagoon depositional environment.  相似文献   
107.
Dielectrophoretic separation of monocytes from cancer cells in a microfluidic chip using electrode pitch optimization     
Zahedi Siani  Omid  Zabetian Targhi  Mohammad  Sojoodi  Mahdi  Movahedin  Mansoureh 《Bioprocess and biosystems engineering》2020,43(9):1573-1586

This study proposes a microfluidic device capable of separating monocytes from a type of cancer cell that is called T-cell acute lymphoblastic leukemia (RPMI-8402) in a continuous flow using negative and positive dielectrophoretic forces. The use of both the hydrodynamic and dielectrophoretic forces allows the separation of RPMI-8402 from monocytes based on differences in their intrinsic electrical properties and sizes. The specific crossover frequencies of monocytes and RPMI-8402 cells have been obtained experimentally. The optimum ranges of electrode pitch-to-channel height ratio at the cross sections with different electrode widths have been generally calculated by numerical simulations of the gradients of the electric field intensities and calculation their effective values (root-mean-square). In the device, the cell sorting has been conducted empirically, and then, the separation performance has been evaluated by analyzing the images before and after dielectrophoretic forces applied to the cells. In this work, the design of a chip with 77 μm gold–titanium electrode pitch was investigated to achieve high purity of monocytes of 95.2%. The proposed device can be used with relatively low applied voltages, as low as 16.5 V (peak to peak). Thus, the design can be used in biomedical diagnosis and chemical analysis applications as a lab-on-chip platform. Also, it can be used for the separation of biological cells such as bacteria, RNA, DNA, and blood cells.

  相似文献   
108.
Lack of PD-L1 Expression by iNKT Cells Improves the Course of Influenza A Infection     
Hadi Maazi  Abinav K. Singh  Anneliese O. Speak  Vincent Lombardi  Jonathan Lam  Bryant Khoo  Kyung Soo Inn  Arlene H. Sharpe  Jae U. Jung  Omid Akbari 《PloS one》2013,8(3)
There is evidence indicating that invariant Natural Killer T (iNKT) cells play an important role in defense against influenza A virus (IAV). However, the effect of inhibitory receptor, programmed death-1 (PD-1), and its ligands, programmed death ligand (PD-L) 1 and 2 on iNKT cells in protection against IAV remains to be elucidated. Here we investigated the effects of these co-stimulatory molecules on iNKT cells in the response to influenza. We discovered that compare to the wild type, PD-L1 deficient mice show reduced sensitivity to IAV infection as evident by reduced weight loss, decreased pulmonary inflammation and cellular infiltration. In contrast, PD-L2 deficient mice showed augmented weight loss, pulmonary inflammation and cellular infiltration compare to the wild type mice after influenza infection. Adoptive transfer of iNKT cells from wild type, PD-L1 or PD-L2 deficient mice into iNKT cell deficient mice recapitulated these findings. Interestingly, in our transfer system PD-L1−/−-derived iNKT cells produced high levels of interferon-gamma whereas PD-L2−/−-derived iNKT cells produced high amounts of interleukin-4 and 13 suggesting a role for these cytokines in sensitivity to influenza. We identified that PD-L1 negatively regulates the frequency of iNKT cell subsets in the lungs of IAV infected mice. Altogether, these results demonstrate that lack of PD-L1 expression by iNKT cells reduces the sensitivity to IAV and that the presence of PD-L2 is important for dampening the deleterious inflammatory responses after IAV infection. Our findings potentially have clinical implications for developing new therapies for influenza.  相似文献   
109.
Protective Oral Vaccination against Infectious bursal disease virus Using the Major Viral Antigenic Protein VP2 Produced in Pichia pastoris     
Omid Taghavian  Holger Spiegel  Rüdiger Hauck  Hafez M. Hafez  Rainer Fischer  Stefan Schillberg 《PloS one》2013,8(12)
Infectious bursal disease virus (IBDV) causes economically important immunosuppressive disease in young chickens. The self-assembling capsid protein (VP2) from IBDV strain IR01 was expressed in Pichia pastoris resulting in the formation of homomeric, 23-nm infectious bursal disease subviral particles (IBD-SVPs) with a yield of 76 mg/l before and 38 mg/l after purification. Anti-IBDV antibodies were detected in chickens injected with purified IBD-SVPs or fed with either purified IBD-SVPs or inactivated P. pastoris cells containing IBD-VP2 (cell-encapsulated). Challenge studies using the heterologous classical IBDV strain (MB3) showed that intramuscular vaccination with 20 µg purified IBD-SVPs conferred full protection, achieved complete virus clearance and prevented bursal damage and atrophy, compared with only 40% protection, 0–10% virus clearance accompanied by severe atrophy and substantial bursal damage in mock-vaccinated and challenge controls. The commercial IBDV vaccine also conferred full protection and achieved complete virus clearance, albeit with partial bursal atrophy. Oral administration of 500 µg purified IBD-SVPs with and without adjuvant conferred 100% protection but achieved only 60% virus clearance with adjuvant and none without it. Moderate bursal damage was observed in both cases but the inclusion of adjuvant resulted in bursal atrophy similar to that observed with live-attenuated vaccine and parenteral administration of 20 µg purified IBD-SVPs. The oral administration of 250 mg P. pastoris cells containing IBD-VP2 resulted in 100% protection with adjuvant and 60% without, accompanied by moderate bursal damage and atrophy in both groups, whereas 25 mg P. pastoris cells containing IBD-VP2 resulted in 90–100% protection with moderate bursal lesions and severe atrophy. Finally, the oral delivery of 50 µg purified IBD-SVPs achieved 40–60% protection with severe bursal lesions and atrophy. Both oral and parenteral administration of yeast-derived IBD-VP2 can therefore induce a specific and protective immune response against IBDV without affecting the growth rate of chickens.  相似文献   
110.
Cryptic Speciation Patterns in Iranian Rock Lizards Uncovered by Integrative Taxonomy     
Faraham Ahmadzadeh  Morris Flecks  Miguel A. Carretero  Omid Mozaffari  Wolfgang B?hme  D. James Harris  Susana Freitas  Dennis R?dder 《PloS one》2013,8(12)
While traditionally species recognition has been based solely on morphological differences either typological or quantitative, several newly developed methods can be used for a more objective and integrative approach on species delimitation. This may be especially relevant when dealing with cryptic species or species complexes, where high overall resemblance between species is coupled with comparatively high morphological variation within populations. Rock lizards, genus Darevskia, are such an example, as many of its members offer few diagnostic morphological features. Herein, we use a combination of genetic, morphological and ecological criteria to delimit cryptic species within two species complexes, D. chlorogaster and D. defilippii, both distributed in northern Iran. Our analyses are based on molecular information from two nuclear and two mitochondrial genes, morphological data (15 morphometric, 16 meristic and four categorical characters) and eleven newly calculated spatial environmental predictors. The phylogeny inferred for Darevskia confirmed monophyly of each species complex, with each of them comprising several highly divergent clades, especially when compared to other congeners. We identified seven candidate species within each complex, of which three and four species were supported by Bayesian species delimitation within D. chlorogaster and D. defilippii, respectively. Trained with genetically determined clades, Ecological Niche Modeling provided additional support for these cryptic species. Especially those within the D. defilippii-complex exhibit well-differentiated niches. Due to overall morphological resemblance, in a first approach PCA with mixed variables only showed the separation between the two complexes. However, MANCOVA and subsequent Discriminant Analysis performed separately for both complexes allowed for distinction of the species when sample size was large enough, namely within the D. chlorogaster-complex. In conclusion, the results support four new species, which are described herein.  相似文献   
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