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排序方式: 共有1295条查询结果,搜索用时 15 毫秒
991.
Size of the Ovulatory Follicle Dictates Spatial Differences in the Oviductal Transcriptome in Cattle
992.
A quantitative acetylcholinesterase enzyme-histochemical study was performed with microdensitometric methods in the hippocampus of the rat in order to correlate this enzymatic activity with the different zones of the hippocampal pyramidal layer. Higher values of acetylcholinesterase activity were found in the CA3 pyramidal zone. CA1 and CA4 showed the same activity, while the stratum oriens at CA3 showed the highest values among the hippocampal layers studied. The results were correlated with differences in septal afferences. 相似文献
993.
Peloi LS Biondo CE Kimura E Politi MJ Lonardoni MV Aristides SM Dorea RC Hioka N Silveira TG 《Experimental parasitology》2011,(4):353-356
The aim of this study was to investigate the effectiveness of Photodynamic Therapy (PDT) using Methylene Blue (MB) as the photosensitizing compound and a Light-Emitting Diode (LED) in American cutaneous leishmaniasis (ACL). Hamsters were experimentally infected with Leishmania (Leishmania) amazonensis. After the development of the lesions in the footpad, the animals were treated with MB three times a week for 3 months. Ten minutes after each application of MB, the lesions were irradiated with LED for 1 h. The lesions were evaluated weekly by the measurement of the hamster footpad thickness. At the end of the treatment the parasitic load was quantified in the regional lymph node of the hamsters. The treatment promoted a decrease in the thickness of infected footpad (P = 0.0001) and reduction in the parasitic load in the regional lymph node (P = 0.0007) of the animals from group treated with MB + LED. PDT using MB + LED in ACL caused by L. amazonensis shows a strong photodynamic effect. This therapy is very promising, once it is an inexpensive system and the own patient can apply it in their wound and in their house without the need of technical assistance. 相似文献
994.
Silva CR Oliveira SM Rossato MF Dalmolin GD Guerra GP da Silveira Prudente A Cabrini DA Otuki MF André E Ferreira J 《Life sciences》2011,88(25-26):1077-1087
AimsIn the present work, we characterize the inflammatory process induced by the topical application of cinnamaldehyde on the skin of mice and verify the participation of transient receptor potential A1 TRPA1 receptors in this process.Main methodsWe measured mouse ear edema and sensitization/desensitization after topical application of cinnamaldehyde or/and capsaicin. We also quantified cellular infiltration through myeloperoxidase (MPO) activity and histological and immunohistochemical analyses and evaluated the expression of TRPV1 and TRPA1 by western blot.Key findingsCinnamaldehyde induced ear edema in mice (1–6 μg/ear) with a maximum effect of 4 μg/ear. Cinnamaldehyde promoted leukocyte infiltration as detected by increasing MPO activity and confirmed by histological analyses. The edema and cellular infiltration evoked by the application of 4 μg/ear of cinnamaldehyde were prevented by topical application of ruthenium red, a non-selective TRP antagonist as well as camphor and HC030031, two TRPA1 receptor antagonists. Cinnamaldehyde-induced edema, but not cellular infiltration, was prevented by topical application of the tachykinin NK1 antagonist, aprepitant, indicating a neuropeptide release phenomenon in this process. Additionally, we observed that repeated topical applications of cinnamaldehyde did not induce changes in sensitization or desensitization with respect to the edema response. Interestingly, repeated treatment with the TRPV1 agonist, capsaicin, abrogated it edematogenic response, confirming the desensitization process and partially decreasing the cinnamaldehyde-induced edema, suggesting the involvement of capsaicin-sensitive fibers.SignificanceOur data demonstrate that the topical application of cinnamaldehyde produces an inflammatory response that is dependent on TRPA1 receptor stimulation. 相似文献
995.
Oikawa PY Giebel BM Sternberg Lda S Li L Timko MP Swart PK Riemer DD Mak JE Lerdau MT 《The New phytologist》2011,191(4):1031-1040
Plant production of methanol (MeOH) is a poorly understood aspect of metabolism, and understanding MeOH production in plants is crucial for modeling MeOH emissions. Here, we have examined the source of MeOH emissions from mature and immature leaves and whether pectin methylesterase (PME) activity is a good predictor of MeOH emission. We also investigated the significance of below-ground MeOH production for mature leaf emissions. We present measurements of MeOH emission, PME activity, and MeOH concentration in mature and immature tissues of tomato (Lycopersicon esculentum). We also present stable carbon isotopic signatures of MeOH emission and the pectin methoxyl pool. Our results suggest that below-ground MeOH production was not the dominant contributor to daytime MeOH emissions from mature and immature leaves. Stable carbon isotopic signatures of mature and immature leaf MeOH were similar, suggesting that they were derived from the same pathway. Foliar PME activity was related to MeOH flux, but unexplained variance suggested PME activity could not predict emissions. The data show that MeOH production and emission are complex and cannot be predicted using PME activity alone. We hypothesize that substrate limitation of MeOH synthesis and MeOH catabolism may be important regulators of MeOH emission. 相似文献
996.
997.
Vieira VC Barral MF Mendoza-Sassi RA Silveira JM Soares MA de Martínez AM 《Memórias do Instituto Oswaldo Cruz》2011,106(4):408-415
Polymorphisms in genes that encode chemokines or their receptors can modulate susceptibility to human immunodeficiency virus (HIV) infection and disease progression. The objective of this study was to assess the frequency of polymorphisms CCR5-Δ32, CCR2-64I, CCR5-59029A and SDF1-3'A and their role in the course of HIV infection in a Southern Brazilian population. Clinical data were obtained from 249 patients for an average period of 6.4 years and genotypes were determined by standard polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism. Survival analyses were conducted for three outcomes: CD4+ T-cell counts below 200 cells/μL, acquired immune deficiency syndrome (AIDS) or death. The frequency of the polymorphisms CCR5-Δ32, CCR2-64I, CCR5-59029A and SDF1-3'A were 0.024, 0.113, 0.487 and 0.207, respectively. CCR5-Δ32 was associated with a reduction in the risk for CD4+ T-cell depletion and with an increased risk for death after AIDS diagnosis. CCR2-64I was associated with a reduction in the risk for developing AIDS. SDF1-3'A was also associated with decreased risk for AIDS, but its effect was only evident when CCR2-64I was present as well. These results highlight the possibility of using these markers as indicators for the prognosis of disease progression and provide evidence for the importance of analysing the effects of gene polymorphisms in a combined fashion. 相似文献
998.
Soares RM Patzer VL Dersch R Wendorff J da Silveira NP Pranke P 《International journal of biological macromolecules》2011,49(4):480-486
The aim of this work has been to elaborate well defined gliadin nanofibers with incorporation of inorganic molecules, such as polyhedral oligomeric silsesquioxane (POSS). Nanofibers were obtained by electrospinning processing, controlling the relevant parameters such as tip-to-collector distance, voltage and feed rate. The fiber mats were characterized by SEM, confocal images, DSC, viscosity, FTIR and conductivimetry analysis. FTIR spectra showed characteristic absorption bands related to the presence of POSS-NH2 within the matrices. SEM micrographs showed that gliadin fibers decreased their dimensions as the amount of POSS-NH2 increased in the spinning solution. The electrical conductivity of gliadin solutions diminished as the concentration of POSS-NH2 was increased. Besides, confocal micrographs revealed that POSS-NH2 might be dispersed as nanocrystals into gliadin and gluten fibers. The dimension of gluten nanofibers was also affected by the POSS-NH2 concentration, but conversely, this dependence was not proportional to the POSS-NH2 amount. Somehow, the interaction between gliadin and POSS-NH2 in aqueous TFE affected the solution viscosity and, as a consequence, higher jet instabilities and thinner fiber dimensions were obtained. 相似文献
999.
Repeke CE Ferreira SB Vieira AE Silveira EM Avila-Campos MJ da Silva JS Santos CF Campanelli AP Trombone AP Garlet GP 《PloS one》2011,6(7):e22526
Chemokines and chemokine receptors have been implicated in the selective migration of leukocyte subsets to periodontal tissues, which consequently influences the disease outcome. Among these chemoattractants, the chemokines CCL3, CCL4 and CCL5 and its receptors, CCR1 and CCR5, have been associated with increased disease severity in mice and humans. Therefore, in this study we investigated the modulation of experimental periodontitis outcome by the treatment with a specific antagonist of CCR1 and 5 receptors, called met-RANTES. C57Bl/6 mice was orally infected with Aggregatibacter actinomycetemcomitans and treated with 0.05, 0.1, 0.5, 1.5 and 5 mg doses of met-RANTES on alternate days, and evaluated by morphometric, cellular, enzymatic and molecular methods. At 0.5 mg up to 5 mg doses, a strong reduction in the alveolar bone loss and inflammatory cell migration were observed. Interestingly, 5 mg dose treatment resulted in the maximum inhibition of inflammatory cell migration, but resulted in a similar inhibition of bone loss when compared with the lower doses, and also resulted in increased bacterial load and CRP response. When 0.5 and 5 mg therapy regimens were compared it was observed that both therapeutic protocols were able to downregulate the levels of pro-inflammatory, Th1-type and osteoclastogenic cytokines, and CD3+ and F4/80+ cells migration to periodontal tissues, but the high dose modulates host response in a more pronounced and unspecific and excessive way, interfering also with the production of antimicrobial mediators such as MPO, iNOS and IgG, and with GR1+ and CD19+ cells migration. Our results demonstrate a thin line between beneficial immunoregulation and impaired host defense during experimental periodontitis, and the determination of the exact equilibrium point is mandatory for the improvement of immune-targeted therapy of periodontitis. 相似文献
1000.
Galetović A Souza RT Santos MR Cordero EM Bastos IM Santana JM Ruiz JC Lima FM Marini MM Mortara RA da Silveira JF 《PloS one》2011,6(11):e27634