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1.
Summary
Lambertz (1954) did not mention Gramineae as plants containing ectodesmata, although he stated that ectodesmata are not bound to special groups of angiosperms but should occur in all families of angiosperms. Schnepe (1959) expressly pointed out that he never succeeded in demonstrating such structures in leaves of Gramineae with his method. In our studies, however, ectodesmata could be shown in leaves of wheat and maize if the fixation mixture contained nitric acid. As in other objects, including species of gymnosperms and pteridophytes, the same distribution of ectodesmata could be observed which was characterized by the formation of rows along the anticlinal walls, crowding in guard-cells and seattering in periclincal walls. 相似文献
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3.
Poliovirus morphogenesis. I. Identification of 80S dissociable particles and evidence for the artifactual production of procapsids. 总被引:10,自引:8,他引:2 下载免费PDF全文
The current model of poliovirus morphogenesis postulates a fundamental role for procapsid, 80S shells that, upon interaction with viral RNA and subsequent proteolytic cleavage, give rise to complete virus particles. Although 80S sedimenting particles can, indeed, be isolated from cytoplasmic extracts of infected cells, their physical properties differ from those reported for procapsids. Far from being stable structures, they can be dissociated by pH 8.5 and 0.1% sodium dodecyl sulfate into slower-sedimenting subunits. The reasons for this discrepancy were investigated, and two main modalities leading to the appearance of procapsids in vitro were identified. The first involves a temperature-mediated conversion of dissociable 80S particles into stable 80S procapsids, and the second involves the self-assembly of endogenous 14S subunits, also primed by an increase in the temperature of cytoplasmic extracts. 相似文献
4.
Loss of function of Arabidopsis NADP‐malic enzyme 1 results in enhanced tolerance to aluminum stress
5.
Volpi Denise Alves Fabiana Villa da Silva Arguelho Alan do Vale Marcos Martinez Deniz Matheus Zopollatto Maity 《International journal of biometeorology》2021,65(10):1695-1705
International Journal of Biometeorology - The aim of this study was to estimate, using data mining, which microclimate and behavioral variables affect the behavior of animals to seek shaded or... 相似文献
6.
Alberto Baldini Alessandro Nota Valentina Assi Fabiana Ballanti Paola Cozza 《Journal of electromyography and kinesiology》2013,23(6):1474-1479
Aim of the studyTo evaluate the intersession reliability of a posturo-stabilometric examination.MethodsSingle blind clinical trial conducted in two sessions over two weeks.44 healthy volunteers free from postural and temporomandibular disorders. All the subjects complied with the criteria for completing the study.All the subjects underwent two sessions of posturo-stabilometric examinations in different visual and mandibular conditions.Sway area, sway length and the coordinates of the center of pressure were evaluated and statistically analyzed using the Intraclass correlation coefficient (ICC).ResultsAll the posturo-stabilometric parameters seemed to have an excellent reproducibility with overall ICCs higher than 70% and good confidence intervals except for the sway area (ICC 0.422 with CI 0.283–0.560 with open eyes and ICC 0.554 with CI 0.424–0.683 with closed eyes).ConclusionsThe posturo-stabilometric examination carried out using a force platform has a good intrasession and intersession reliability, especially considering sway velocity, COP X and COP Y parameters. The force platform usefulness in analyzing static posture is confirmed in any medical field. 相似文献
7.
Danilo ML Prado Fabiana B Benatti Ana L de Sá-Pinto Ana P Hayashi Bruno Gualano Rosa MR Pereira Adriana ME Sallum Eloisa Bonfá Clovis A Silva Hamilton Roschel 《Arthritis research & therapy》2013,15(2):R46
Introduction
Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.Methods
Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).Results
The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.Conclusion
A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.Trial registration
NCT01515163. 相似文献8.
Silvia M. Ayub-Ferreira Sandrigo Mangini Victor S. Issa Fátima D. Cruz Fernando Bacal Guilherme V. Guimar?es Paulo R. Chizzola Germano E. Concei??o-Souza Fabiana G. Marcondes-Braga Edimar A. Bocchi 《PLoS neglected tropical diseases》2013,7(4)
Background
Sudden death has been considered the main cause of death in patients with Chagas heart disease. Nevertheless, this information comes from a period before the introduction of drugs that changed the natural history of heart failure. We sought to study the mode of death of patients with heart failure caused by Chagas heart disease, comparing with non-Chagas cardiomyopathy.Methods and results
We examined the REMADHE trial and grouped patients according to etiology (Chagas vs non-Chagas) and mode of death. The primary end-point was all-cause, heart failure and sudden death mortality; 342 patients were analyzed and 185 (54.1%) died. Death occurred in 56.4% Chagas patients and 53.7% non-Chagas patients. The cumulative incidence of all-cause mortality and heart failure mortality was significantly higher in Chagas patients compared to non-Chagas. There was no difference in the cumulative incidence of sudden death mortality between the two groups. In the Cox regression model, Chagas etiology (HR 2.76; CI 1.34–5.69; p = 0.006), LVEDD (left ventricular end diastolic diameter) (HR 1.07; CI 1.04–1.10; p<0.001), creatinine clearance (HR 0.98; CI 0.97–0.99; p = 0.006) and use of amiodarone (HR 3.05; CI 1.47–6.34; p = 0.003) were independently associated with heart failure mortality. LVEDD (HR 1.04; CI 1.01–1.07; p = 0.005) and use of beta-blocker (HR 0.52; CI 0.34–0.94; p = 0.014) were independently associated with sudden death mortality.Conclusions
In severe Chagas heart disease, progressive heart failure is the most important mode of death. These data challenge the current understanding of Chagas heart disease and may have implications in the selection of treatment choices, considering the mode of death.Trial Registration
ClinicalTrails.gov (REMADHE) NCT00505050相似文献9.
10.
Alessio Cimmino Anna Andolfi Fabiana Avolio Abbas Ali Nurhayat Tabanca Ikhlas A. Khan Antonio Evidente 《化学与生物多样性》2013,10(7):1239-1251
Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. From a preliminary screening of fungal phytotoxins, cyclopaldic acid ( 1 ), seiridin ( 2 ), sphaeropsidin A ( 4 ), and papyracillic acid ( 5 ) were evaluated for their biting deterrent and larvicidal activities against Ae. aegypti L. Because compounds 1, 2, 4 , and 5 exhibited mosquito biting deterrent activities and 1 and 4 demonstrated larvicidal activities, further structure? activity relationship studies were initiated on these toxins. In biting‐deterrence bioassays, 1, 2, 4 , and 5 , 3,8‐didansylhydrazone of cyclopaldic acid, 1F , 5‐azidopentanoate of cyclopaldic acid A, 1G , the reduced derivative of cyclopaldic acid, 1 H , isoseiridin ( 3 ), 2′‐O‐acetylseiridin ( 2A ), 2′‐oxoseiridin ( 2C ), 6‐O‐acetylsphaeropsidin A ( 4A ), 8,14‐methylensphaeropsidin A methyl ester ( 4B ), and sphaeropsidin B ( 4C ) showed activities higher than the solvent control. Sphaeropsidin B ( 4C ) was the most active compound followed by 2A , while the other compounds were less active. Biting‐deterrence activity of compound 4C was statistically similar to DEET. In the larvicidal screening bioassays, only compounds 1 and 4 demonstrated larvicidal activities. Based on LD50 values, compound 4 (LD50 36.8 ppm) was significantly more active than compound 1 (LD50 58.2 ppm). However, the activity of these compounds was significantly lower than permethrin. 相似文献