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1.
Abstract. Paraformaldehyde-fixed platelets from normal donors were used for detection of antibody to platelet by in vitro sensitization (indirect method) utilizing rabbit anti-human IgG heavy chain specific antibody-coated polyacrylamide gels (Immunobeads). The sensitized platelets formed rosettes with Immunobeads and the positive rosette count was over 30%, while control showed less than 8% when normal sera were used. This method was also applicable for detecting antibody-sensitized platelets in vivo (direct method) in patients with autoimmune thrombocytopenia. This method is simple, rapid and reproducible for clinical use. Direct and indirect immunofluorescent antibody tests and a blocking test with anti-human serum also supported the results of Immunobead rosetting technique.  相似文献   
2.
This study was conducted to measure selected hematological parameters in goats naturally infected with Anaplasma ovis. In this study 193 blood samples were collected from adult and young goats in north (Gonbad) and northeast (Mashhad) of Iran. Out of the 193 blood samples, 123 samples were positive (infected group) and 70 samples were negative (uninfected group) for A. ovis by polymerase chain reaction. Hematological analysis was carried out on 47 samples from the infected group and 37 samples from the uninfected group. Hematological analysis indicated significant decreases (P?<?0.01) in RBC counts, HCT values, and hemoglobin concentrations in the A. ovis-infected group of goats compared to the uninfected group (P?<?0.01). The mean corpuscular volume, mean corpuscular hemoglobin, WBC counts, lymphocytes, eosinophils, and monocytes in the infected group were lower but neutrophils were higher than in the uninfected group. These differences were not statistically significant (P?>?0.05). The result from this study revealed that A. ovis infection in goats is associated with marked changes in hematological parameters.  相似文献   
3.
Cytokines are mediators for polarization of immune response in vaccines. Studies show that co‐immunization of DNA vaccines with granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) can increase immune responses. Here, experimental mice were immunized with HIV‐1tat/pol/gag/env DNA vaccine with GM‐CSF and boosted with recombinant vaccine. Lymphocyte proliferation with Brdu and CTL activity, IL‐4, IFN‐γ, IL‐17 cytokines, total antibody, and IgG1 and IgG2a isotypes were assessed with ELISA. Results show that GM‐CSF as adjuvant in DNA immunization significantly increased lymphocyte proliferation and IFN‐γ cytokines, but CTL response was tiny increased. Also GM‐CSF as adjuvant decreased IL‐4 cytokine vs mere vaccine group. IL‐17 in the group that immunized with mixture of DNA vaccine/GM‐CSF was significantly increased vs DNA vaccine group. Result of total antibody shows that GM‐CSF increased antibody response in which both IgG1 and IgG2a increased. Overall, results confirmed the beneficial effect of GM‐CSF as adjuvant to increase vaccine immunogenicity. The hallmark result of this study was to increase IL‐17 cytokine with DNA vaccine/GM‐CSF immunized group. This study for the first time provides the evidence of the potency of GM‐CSF in the induction of IL‐17 in response to a vaccine, which is important for control of infection such as HIV‐1.  相似文献   
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A new model for prediction of the effective permeability of gases in mixed matrix membranes (MMMs), considering the effects of particle shape and the interfacial layer, is presented. The proposed model treats core filler particles and interfacial shell layers as complex particles. Moreover, the Bruggman mathematical procedure is used to improve the accuracy of the presented model for high concentrations of fillers in MMMs. Also, an appropriate uniform criterion is established to make efficient use of the new model for various experimental data to avoid the need for curve‐fitting procedures. Finally, the proposed model is examined for several sets of experimental data.

  相似文献   

6.
Lasers in Medical Science - Low-level laser has been indicated to have the capability to facilitate the differentiation of the osteoclastic and osteoblastic cells which are responsible for the bone...  相似文献   
7.
Increases in burned area and large fire occurrence are widely documented over the western United States over the past half century. Here, we focus on the elevational distribution of forest fires in mountainous ecoregions of the western United States and show the largest increase rates in burned area above 2,500 m during 1984 to 2017. Furthermore, we show that high-elevation fires advanced upslope with a median cumulative change of 252 m (−107 to 656 m; 95% CI) in 34 y across studied ecoregions. We also document a strong interannual relationship between high-elevation fires and warm season vapor pressure deficit (VPD). The upslope advance of fires is consistent with observed warming reflected by a median upslope drift of VPD isolines of 295 m (59 to 704 m; 95% CI) during 1984 to 2017. These findings allow us to estimate that recent climate trends reduced the high-elevation flammability barrier and enabled fires in an additional 11% of western forests. Limited influences of fire management practices and longer fire-return intervals in these montane mesic systems suggest these changes are largely a byproduct of climate warming. Further weakening in the high-elevation flammability barrier with continued warming has the potential to transform montane fire regimes with numerous implications for ecosystems and watersheds.

Fire is an integral component of most forested lands and provides significant ecological services (1). However, burned area, fire size, the number of large fires, and the length of fire season have increased in the western United States in recent decades (2, 3). Increasing fire activity and the expansion of wildland urban interface (4) collectively amplified direct and indirect fire-related loss of life and property (5, 6) and contributed to escalating fire suppression costs (7). While increased biomass due to a century of fire exclusion efforts is hypothesized to have partially contributed to this trend (8), climate change is also implicated in the rise of fire activity in the western United States (911).Although increases in forest fire activity are evident in all major forested lands in the western United States (2, 12, 13), an abundance of moisture—due to snowpack persistence, cooler temperatures, and delayed summer soil and fuel drying—provides a strong buffer of fire activity (13) and longer fire-return intervals (14) at high elevations. Recent studies, however, point to changing fire characteristics across many ecoregions of the western United States (15), including high-elevation areas of the Sierra Nevada (16), Pacific Northwest, and Northern Rockies (12, 17). These studies complement documented changes in montane environments including amplified warming with elevation (18), widespread upward elevational shift in species (19), and increased productivity in energy-limited high-elevation regions that enhance fuel growth and connectivity (20). These changes have been accompanied by longer snow-free periods (21), increased evaporative demand (9), and regional declines in fire season precipitation frequency (11) across the western United States promoting increased fuel ignitability and flammability that have well-founded links to forest burned area. A warmer climate is also conducive to a higher number of convective storms and more frequent lightning strikes (22).In this study, we explore changes in the elevational distribution of burned forest across the western United States and how changes in climate have affected the mesic barrier for high-elevation fire activity. We focus on changes in high-elevation forests that have endured fewer direct anthropogenic modifications compared to drier low-elevation forests that had frequent low-severity fires prior to European colonization and have been more subject to changes in settlement patterns as well as fire suppression and harvest (23, 24); we also pose the following questions: 1) Has the elevational distribution of fire in the western US forests systematically changed? and 2) What changes in biophysical factors have enabled such changes in high-elevation fire activity? We explore these questions across 15 mountainous ecoregions of the western United States using records from large fires (>405 ha) between 1984 and 2017 [Monitoring Trends in Burn Severity (MTBS) (25)], a 10-m–resolution digital elevation model, and daily high-spatial–resolution surface meteorological data [gridMET (26)].We focus on the trends in Z90—defined as the 90th percentile of normalized annual elevational distribution of burned forest in each ecoregion. Here, the term “normalized” essentially refers to the fraction of forest area burned by elevation. We complement this analysis by examining trends in burned area by elevational bands and using quantile regression of normalized annual forest fire elevation. We then assess the interannual relationships between Z90 and vapor pressure deficit (VPD) and compare the upslope advance in montane fire to elevational climate velocity of VPD during 1984 to 2017. Specifically, we use VPD trends and VPD–high-elevation fire regression to estimate VPD-driven changes in Z90 and BA90— defined as annual burned area above the 90th percentile of forest elevational distribution in each ecoregion—during 1984 to 2017.  相似文献   
8.
9.

Background

The present study was carried out to investigate the accurate status of ovine Theileria infection in sheep from Ahvaz and surrounding region, a tropical area southwest Iran.

Methods

A PCR-RFLP method based on 18S ribosomal RNA gene was designed which could detect and differentiate Theileria and Babesia spp. and also differentiate main Theileria species in sheep at the same time. 119 sheep blood samples were collected from Ahvaz and surroundings.

Results

Microscopic examination of blood smears revealed 69.7% (83/119) infection with Theileria spp. Of the total samples subjected to PCR, 89% (106/119) were found to be positive, all of which were identified as Theileria by RFLP analysis using enzyme Hind II. In enzymatic digestion of PCR products by Vsp I, 91.5% (97/106) of Theileria positive samples were identified as T. ovis while mixed Theileria infections were found in 9 samples. The samples with mixed infections were analyzed with an additional nested PCR-RFLP method, by HpaII enzyme digestion. 3 samples with T. lestoquardi infection, 1 sample with T. ovis and T. annulata, 1 sample with T. lestoquardi and T. annulata, and 4 samples with T. ovis, T. lestoquardi and T. annulata mixed infections were detected.

Conclusion

Ovine theileriosis caused by T. ovis is highly prevalent in southwest Iran while T. lestoquardi and T. annulata infection can be detected in a lesser propor-tion of sheep in this region. The new PCR-RFLP method that was designed in this study, can serve as a beneficial diagnostic tool, especially in T. ovis prevalent re-gions.  相似文献   
10.
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