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Milad Aeini Hossein Mirzaee Seyed Mohsen Taghavi Gholam Reza Khodakaramian Mehdi Amiri Mazhar 《Archives Of Phytopathology And Plant Protection》2013,46(18):2257-2262
Ficus benjamina, commonly known as weeping fig, Benjamin’s fig or Ficus tree is a species of flowering plant in the family of Moraceae. It is native to south and south-east Asia and Australia. Crown gall tumours were collected from branches of one-year-old weeping fig (F. benjamina L.) trees. A total of 50 strains of Agrobacterium tumefaciens were isolated from diseased Ficus plants and their morphological, molecular and biochemical characteristics were studied; pathogenicity tests on tomato, F. benjamina and Bryophyllum daigremontianum were also conducted. Based on the biochemical characteristics, pathogenicity test and PCR amplification of 730?bp fragment using VCR\VCF primers, the tested bacterial strains were identified as A. tumefaciens. This is the first report of crown gall on F. benjamina in Isfahan and Fars provinces of Iran. 相似文献
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Irfan Ullah Mohammad Sayyar Khan Shahin Shah Khan Waqar Ahmad Lingjie Zheng Syed Usman Ali Shah Mazhar Ullah Aqib Iqbal 《Saudi Journal of Biological Sciences》2021,28(1):970
The present experiment was designed to isolate bacterial strains from the brick kiln soil and to check the activity and enzyme kinetics of amylase from these isolates. The bacterial colonies were isolated from soil samples through the serial dilution method. The bacterial isolates were identified through morphological, electron microscopic and molecular analysis. The 16S ribosomal RNA sequences of the isolates IR-1, IR-2, IR-3, IR-8, and IR-9 showed high similarities with Bacillus tequilensis, Bacillus paramycoides, Proteus alimentorum, Bacillus wiedmannii, and Pseudomonas aeruginosa, respectively. All of the bacterial isolates showed a positive catalase activity except IR-9. Furthermore, the isolates showed variable antagonistic effects against different bacterial pathogens. All of the strains produced indole acetic acid (IAA), and the concentrations increased in the presence of tryptophan application. The isolates showed the amylase enzyme activity and maximum activity of isolates was achieved in 4% starch concentration. The IR-9 isolate showed the highest amylase activity of 5.9 U/ml. The Vmax values of the extracellular amylase from different bacterial isolates ranged between 12.90 and 50.00 IU ml−1. The lowest Km value of 6.33 mg starch was recorded for IR-8 and the maximum Kcat value of 2.50 min−1 was observed for IR-3. The amylase activity of the isolates was significantly affected by a range of different incubation time, temperature, and pH values. Further tests are required before the potential utilization of these isolates for amylase production, and in the biopesticide and biofertilizer applications. 相似文献
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Fourteen spermine-resistant mutants of Arabidopsis thaliana (L.) Heynh. have been isolated from EMS-mutagenized M2 seeds by screening for germination seedlings on a medium containing a germination inhibitory concentration of spermine. Two of these mutants have been studied initially. Genetic analysis indicated that the two mutants are allelic and the spermine resistance is due to recessive nuclear mutations at a locus we have designated SPR1. Mutant spr1-1 exhibits large, longitudinally folded-in cauline leaves whereas mutant spr1-2 is characterized by vigorous growth, large longitudinally folded-in cauline leaves, prominent flowers with 4–8 sepals, 6–8 petals, 6 (rarely 7) stamens of equal lengths, and 2–4 carpellary club-shaped pistil. Both mutants are resistant to exogenous spermine but are as sensitive as the wild-type to spermidine and putrescine. 相似文献
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Khan MH Kunselman AR Leuenberger UA Davidson WR Ray CA Gray KS Hogeman CS Sinoway LI 《American journal of physiology. Heart and circulatory physiology》2002,282(6):H2210-H2215
Bed rest reduces orthostatic tolerance. Despite decades of study, the cause of this phenomenon remains unclear. In this report we examined hemodynamic and sympathetic nerve responses to graded lower body negative pressure (LBNP) before and after 24 h of bed rest. LBNP allows for baroreceptor disengagement in a graded fashion. We measured heart rate (HR), cardiac output (HR x stroke volume obtained by echo Doppler), and muscle sympathetic nerve activity (MSNA) during a progressive and graded LBNP paradigm. Negative pressure was increased by 10 mmHg every 3 min until presyncope or completion of -60 mmHg. After bed rest, LBNP tolerance was reduced in 11 of 13 subjects (P <.023), HR was greater (P <.002), cardiac output was unchanged, and the ability to augment MSNA at high levels of LBNP was reduced (rate of rise for 30- to 60-mmHg LBNP before bed rest 0.073 bursts x min(-1) x mmHg(-1); after bed rest 0.035 bursts x min(-1) x mmHg(-1); P < 0.016). These findings suggest that 24 h of bed rest reduces sympathetic nerve responses to LBNP. 相似文献
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Palatal length in cleft palate as a predictor of speech outcome 总被引:1,自引:0,他引:1
Randall P LaRossa D McWilliams BJ Cohen M Solot C Jawad AF 《Plastic and reconstructive surgery》2000,106(6):1254-9; discussion 1260-1
In an attempt to predict which patients might benefit from primary posterior pharyngeal flaps done at the time of palatal repair, palatal length was assessed before palatal repair and the patient was placed in one of four categories. Patients with longer palates preoperatively had statistically better speech outcomes than patients with shorter palates. Statistical significance was found for most speech parameters. Information on presurgical palatal length can be useful in predicting which patients might profit from primary "pharyngoplasties." 相似文献
90.
Mohammed Jawad Thomas Hone Eszter P. Vamos Valeria Cetorelli Christopher Millett 《PLoS medicine》2021,18(9)
BackgroundArmed conflicts have major indirect health impacts in addition to the direct harms from violence. They create enduring political instability, destabilise health systems, and foster negative socioeconomic and environmental conditions—all of which constrain efforts to reduce maternal and child mortality. The detrimental impacts of conflict on global maternal and child health are not robustly quantified. This study assesses the association between conflict and maternal and child health globally.Methods and findingsData for 181 countries (2000–2019) from the Uppsala Conflict Data Program and World Bank were analysed using panel regression models. Primary outcomes were maternal, under-5, infant, and neonatal mortality rates. Secondary outcomes were delivery by a skilled birth attendant and diphtheria, pertussis, and tetanus (DPT) and measles vaccination coverage. Models were adjusted for 10 confounders, country and year fixed effects, and conflict lagged by 1 year. Further lagged associations up to 10 years post-conflict were tested. The number of excess deaths due to conflict was estimated. Out of 3,718 country–year observations, 522 (14.0%) had minor conflicts and 148 (4.0%) had wars. In adjusted models, conflicts classified as wars were associated with an increase in maternal mortality of 36.9 maternal deaths per 100,000 live births (95% CI 1.9–72.0; 0.3 million excess deaths [95% CI 0.2 million–0.4 million] over the study period), an increase in infant mortality of 2.8 per 1,000 live births (95% CI 0.1–5.5; 2.0 million excess deaths [95% CI 1.6 million–2.5 million]), a decrease in DPT vaccination coverage of 4.9% (95% CI 1.5%–8.3%), and a decrease in measles vaccination coverage of 7.3% (95% CI 2.7%–11.8%). The long-term impacts of war were demonstrated by associated increases in maternal mortality observed for up to 7 years, in under-5 mortality for 3–5 years, in infant mortality for up to 8 years, in DPT vaccination coverage for up to 3 years, and in measles vaccination coverage for up to 2 years. No evidence of association between armed conflict and neonatal mortality or delivery by a skilled birth attendant was found. Study limitations include the ecological study design, which may mask sub-national variation in conflict intensity, and the quality of the underlying data.ConclusionsOur analysis indicates that armed conflict is associated with substantial and persistent excess maternal and child deaths globally, and with reductions in key measures that indicate reduced availability of organised healthcare. These findings highlight the importance of protecting women and children from the indirect harms of conflict, including those relating to health system deterioration and worsening socioeconomic conditions.Mohammed Jawad and co-workers report on a global analysis of maternal and child health outcomes in situations of armed conflict. 相似文献