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1.
Walid Barake Jane Caldwell Adrian Baranchuk 《Indian pacing and electrophysiology journal》2013,13(1):45-51
This report details the case of 17 year old identical twins who both presented with paroxysmal supraventricular tachycardia (PSVT). Electrophysiological studies revealed atrioventricular nodal reentry tachycardia (AVNRT) in both twins. Successful but technically challenging slow pathway ablation was performed in both twins. This is the first reported case of confirmed AVNRT in identical twins which adds strong evidence to heritability of the dual AV node physiology and AVNRT. A review of the current literature regarding PSVT in monozygotic twins is provided. 相似文献
2.
Jimenez-Candil J Morinigo JL Ledesma C Leon V Martín-Luengo C 《Indian pacing and electrophysiology journal》2008,8(3):158-171
Background
In atrioventricular nodal re-entrant tachycardias (AVNRT), the achievement of Junctional Rhythms (JR) during Radiofrequency Ablation (RF) is a sensitive but non-specific marker of success. Our aim is to analyze prospectively the predictors of non-inducibility of AVNRT, focusing on the characteristics of the JR.Methods
We included 75 patients with reproducibly inducible AVNRT. Ablation was performed following an electro-anatomical approach. After each application, the induction protocol was repeated.Results
A total of 341 applications were performed. Although the achievement of ≥1 JR was necessary to obtain the non-inducibility, and the cumulative number of junctional beats (CJB) was higher in effective applications, no CJB cut-off was associated with a success rate higher than 75%. After the observation of a significant correlation between the sinus cycle length (CL) pre-RF and the CL of the JR (JR-CL) (c=0.52; p<0.001), the sinus CL pre-RF/JR-CL ratio (CL-ratio) adequately differentiated the successful vs. unsuccessful applications: 1.41±0.23 vs. 1.17±0.2 (p<0.001). In a multivariate analysis, a CBJ 11 (p<0.001) and a CL-ratio 1.25 (p<0.001) were found to be the only independent predictors of success. The combination of ≥ 11 of CJB with a CL ratio ≥ 1.25 achieved non-inducibility in 97% of our patients.Conclusion
1) The specificity of the occurrence of JR as a marker of the successful ablation of AVNRT is increased by the CL-ratio. 2) The achievement of ≥ 11 of CJB with a CL ratio ≥ 1.25 predicts non-inducibility in almost all patients. 相似文献3.
房室结多径路在临床中常见,其食道电生理有较典型特征,如多种频率心动过速。我们发现一例食道调搏存在两种频率心动过速患者,第一次在右延伸处成功慢径改良后较长时间不能发现另一条慢径存在,40分钟后另一条慢径才表现并于左延长处成功消融。提示如食道电生理发现存在多径路时心内电生理一定要多次重复检查,必要时延长观察时间,力争一次完整消融多条径路。 相似文献
4.
Bhalaghuru Chokkalingam Mani Behzad B Pavri 《Indian pacing and electrophysiology journal》2014,14(1):12-25
More than half a century has passed since the concept of dual atrioventricular (AV) nodal pathways physiology was conceived. Dual AV nodal pathways have been shown to be responsible for many clinical arrhythmia syndromes, most notably AV nodal reentrant tachycardia. Although there has been a considerable amount of research on this topic, the subject of dual AV nodal pathways physiology remains heavily debated and discussed. Despite advances in understanding arrhythmia mechanisms and the widespread use of invasive electrophysiologic studies, there is still disagreement on the anatomy and physiology of the AV node that is the basis of discontinuous antegrade AV conduction. The purpose of this paper is to review the concept of dual AV nodal pathways physiology and its varied electrocardiographic manifestations. 相似文献
5.
《Indian pacing and electrophysiology journal》2020,20(4):147-153
BackgroundVoltage mapping is critical to define substrate during ablation. In ventricular tachycardia, abnormal potentials may be targets. However, wavefront of activation could impact local signal characteristics. This may be particularly true when comparing sinus rhythm versus paced rhythms. We sought to determine how activation wavefront impacts electrogram characteristics.MethodsPatients with ischemic cardiomyopathy, ventricular tachycardia, and without fascicular or bundle branch block were included. Point by point mapping was done and at each point, one was obtained during an atrial paced rhythm and one during a right ventricular paced rhythm. Signals were adjudicated after ablation to define late potentials, fractionated potentials, and quantify local voltage. Areas of abnormal voltage (defined as <1.5 mV) were also determined.Results9 patients were included (age 61.3 ± 9.2 years, 56% male, mean LVEF 34.9 ± 8.6%). LV endocardium was mapped with an average 375 ± 53 points/rhythm. Late potentials were more frequent during right ventricular pacing (51 ± 21 versus 32 ± 15, p < 0.01) while overall scar area was higher during atrial pacing (22 ± 11% vs 13 ± 7%, p < 0.05). In 1/9 patients, abnormal potentials were seen during a right ventricular paced rhythm that were not apparent in an atrial paced rhythm, ablation of which resulted in non-inducibility.ConclusionRhythm in which mapping is performed has an impact on electrogram characteristics. Whether one rhythm is preferable to map in remains to be determined. However, it is possible defining local signals during normal conduction as well as variable paced rhythms may impart a greater likelihood of elucidating arrhythmogenic substrate. 相似文献
6.
《Indian pacing and electrophysiology journal》2022,22(1):18-23
BackgroundThis review aims to determine if patients who undergo atrial fibrillation (AF) ablation with heart failure with preserved ejection fraction (HFpEF) do better, or worse or the same compared to patients with heart failure with reduced ejection fraction (HFrEF).MethodsA search of MEDLINE and EMBASE was performed using the search terms: “atrial fibrillation”, “ablation” and terms related to HFpEF and HFrEF in order to identify studies that evaluated one or more of i) AF recurrence, ii) periprocedural complications and iii) adverse outcomes at follow up for patients with HFpEF and HFrEF who underwent AF ablation. Data was extracted from included studies and statistically pooled to evaluate adverse events and AF recurrence.Results5 studies were included in this review and the sample size of the studies ranged from 91 to 521 patients with heart failure. There was no significant difference in the pooled rate for no AF or symptom recurrence after AF ablation comparing patients with HFpEF vs HFrEF (RR 1.07 95%CI 0.86–1.33, p = 0.15). The most common complications were access site complications/haematoma/bleeding which occurred in similar proportion in each group; HFpEF (3.1%) and HFrEF (3.1%). In terms of repeat ablations, two studies were pooled to yield a rate of 78/455 (17.1%) for HFpEF vs 24/279 (8.6%) for HFrEF (p = 0.001.ConclusionsHeart failure patients with preserved or reduced ejection fraction have similar risk of AF or symptom recurrence after AF ablation but two studies suggest that patients with HFpEF are more likely to have repeat ablations. 相似文献
7.
Xinru Chen Yu Zhang Jiabin Lu Chunwei Xu Jianzhong Liang Fang Wang Wenyong Sun Sangao Fang Jingping Yuan Huijuan Wang Hui Wang Xuewen Liu Likun Chen 《Translational oncology》2017,10(2):115-120
PURPOSE: The incidence of anaplastic lymphoma kinase (ALK) rearrangement in pulmonary sarcomatoid carcinoma (PSC) is controversial. In this study, we aimed to reveal the reliable frequency and the clinical-pathologic characteristics of pulmonary sarcomatoid carcinoma (PSC) with ALK rearrangement in Chinese population, and to provide insight into the translatability of anti-ALK treatment in this treatment-refractory disease. METHODS: Immunohistochemistry (IHC) using a Ventana anti-ALK (D5F3) rabbit monoclonal antibody was performed in 141 PSC specimens collected from multiple medical centers. IHC-positive cases were then confirmed using ALK fluorescent in situ hybridization (FISH). The incidence rates and clinical-pathologic characteristics of ALK-rearranged PSC were then analyzed. Response to ALK inhibitor crizotinib in a patient with ALK-rearranged PSC was evaluated according to the response evaluation criteria for solid tumors (RECIST) version 1.1. RESULTS: Five of 141 (3.5%) of PSCs showed ALK rearrangement-positive by IHC and then were confirmed by FISH. Two were carcinosarcomas and the other three were pulmonary pleomorphic carcinoma (PPC). Strong positive ALK rearrangement was observed in both the epithelioid and sarcomatoid components. The median age of ALK-positive patients was younger than that of ALK-negative patients. PSCs in never-smokers were more likely to harbor ALK rearrangement than those in former or current smokers (P < .05). A 40-year-old woman diagnosed with ALK-rearranged PPC experienced a partial response (?32%) to the ALK inhibitor crizotinib. CONCLUSIONS: The incidence rates of ALK rearrangement in PSC in the Chinese population are similar to those of other subtypes of NSCLC. PSCs in younger never-smokers are more often to harbor ALK rearrangement. ALK inhibitors may serve as an effective treatment for ALK-rearranged PSC. 相似文献
8.
Shaoming Lin Ruilan Chen Song Zhu Huijun Wang Lianfang Wang Jian Zou Jingdong Yan Xiangdong Zhang Dimitrios Farmakiotis Xiaojiang Tan Eleftherios Mylonakis 《Mycopathologia》2018,183(4):679-689
Background
Candidemia is one of the most common nosocomial bloodstream infections. Early diagnosis and antifungal treatment improve clinical outcomes in some studies but not all, with diverse data reported from different institutions. Similarly, antifungal resistance is more common in the USA than in Europe, but there is little data regarding the microbiology and clinical course of candidemia in adult patients in Asia.Aims
(1) To capture species distribution and drug resistance rates among Candida bloodstream isolates, (2) to describe clinical features of candidemia, and (3) to identify factors associated with all-cause mortality, with emphasis on early initiation of antifungal treatment, at a large tertiary University Hospital in China.Methods
In this single-center retrospective study, we identified all patients with candidemia, between 2008 and 2014. Demographic and clinical characteristics, microbiological information, details of antifungal therapy and clinical outcomes were collected.Results
We studied 166 patients. 71 (42.8%) had cancer. Candida albicans was the most frequent species (37.3%), followed by C. parapsilosis (24.1%), C. tropicalis (22.8%), and C. glabrata (14.5%). Antifungal resistance was more frequent in non-albicans strains and especially C. glabrata. Twenty patients received inappropriate treatment with all-cause mortality of 35%. The remaining 146 patients had significantly lower mortality (21.9%, P?=?0.045). Among patients who received antifungal treatment, mortality rate increased with time to appropriate antifungal therapy (AAT): 13.7%, for?<?24 h, 21.1% for 24–48 h, 23.1% for?>?48 h, and 32.4% among patients who received no AT (χ2 for trend P?=?0.039). Initiating AAT more than 24 h after blood culture collection was an independent risk factor for mortality, after adjustment for other confounders (OR 7.1, 95% CI 1.3–39.4, P?=?0.024).Conclusions
Candida albicans was the most frequent cause of candidemia at a large tertiary hospital in China, but antifungal resistance is a growing concern among non-albicans Candida species. The mortality rate of patients treated with ineffective antifungal agents based on in vitro susceptibilities was similar to that of patients who received no treatment at all, and delayed initiation of antifungal treatment was associated with increased risk of death.9.
Kevin A. Parker 《Restoration Ecology》2008,16(2):204-209
The World Conservation Union (1987) defines a translocation as a release of animals with the intention of establishing, reestablishing, or augmenting an existing population. Despite frequent use as a tool for the management of threatened and endangered wildlife, the full benefits of translocations often go unrealized. In this article, I demonstrate how translocations can achieve outputs for conservation management, conservation science, and the wider human community, using North Island (NI) Saddleback or Tieke ( Philesturnus rufusater ) as an illustrative example. From a conservation management perspective, NI Saddleback have been salvaged from a relic population of less than 500 birds on 484-ha Hen Island to a metapopulation of approximately 6,000 birds on 13 offshore islands and at two mainland New Zealand sites. These translocations have reduced the risk of global extinction for this species and helped restore the ecosystems involved. All these translocations have occurred in the past 42 years from known source populations and with known numbers of birds released. The resulting replicated serial population bottlenecks provide numerous scientific opportunities for conservation and biological research. Although the first Saddleback translocations were to reserves closed to the public, subsequent translocations have been to open reserves, providing the wider human community with an opportunity to see and be actively involved in the management of a threatened endemic species. This has raised the profile of both NI Saddleback and other species and has provided wider community conservation benefits. These three outputs illustrate the value of translocations for resource management and conservation science and for increasing community interest, participation, and investment in biological conservation. 相似文献
10.
Limb ablation and regeneration in Harmonia axyridis: costs for regenerators,but benefits for their progeny
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Ahmed H. Abdelwahab J.P. Michaud Mohamed H. Bayoumy Samir S. Awadalla Mohamed El‐Gendy 《Entomologia Experimentalis et Applicata》2018,166(2):124-130
Previous work revealed that Harmonia axyridisPallas (Coleoptera: Coccinellidae) in Beijing, China, were capable of regenerating a forelimb amputated in the fourth instar; 75% of surviving individuals fully regenerated the limb during pupation. In this study, we tested a population of H. axyridis invasive in North America and found that virtually 100% of beetles surviving the operation successfully regenerated the limb. Ablated/regenerated beetles spent longer in pupation, and emerging females were smaller than controls. However, reproductive success was unaffected in all pairwise crosses of control/regenerated adults; there were no differences in pre‐oviposition period, the time required to produce 10 clutches, 10‐day fecundity, or the fertility of eggs, whereas ablated/regenerated parents paid a developmental cost, their progeny obtained benefits. Offspring of crosses that included a regenerated parent tended to have faster larval development than the control cross, although not all were significantly different from controls. However, when either or both parents were ablated and regenerated, their daughters were heavier than controls at emergence. Limb regeneration during pupation appears to activate a physiological cascade which increases the magnitude of beneficial parental effects normally conferred to progeny, possibly via pleiotropic effects. The invasive North American H. axyridis population appears to have higher regeneration capacity than the Chinese population tested previously, although how regeneration capacity might be associated with invasiveness remains unclear. Limb regeneration ability may be a side effect of selection on other traits that confer high fitness under either natural or sexual selection, as it seems unlikely to confer fitness benefits directly in this species. 相似文献
11.
Seth H Sheldon Joseph J Gard Samuel J Asirvatham 《Indian pacing and electrophysiology journal》2010,10(8):357-371
Premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia (NSVT) are frequently encountered and a marker of electrocardiomyopathy. In some instances, they increase the risk for sustained ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. While often associated with a primary cardiomyopathy, they have also been known to cause tachycardia-induced cardiomyopathy in patients without preceding structural heart disease. Medical therapy including beta-blockers and class III anti-arrhythmic agents can be effective while implantable cardiac defibrillators (ICD) are indicated in certain patients. Radiofrequency ablation (RFA) is the preferred, definitive treatment in those patients that improve with anti-arrhythmic therapy, have tachycardia-induced cardiomyopathy, or have certain subtypes of PVCs/NSVT. We present a review of PVCs and NSVT coupled with case presentations on RFA of fascicular ventricular tachycardia, left-ventricular outflow tract ventricular tachycardia, and Purkinje arrhythmia leading to polymorphic ventricular tachycardia. 相似文献
12.
Judith A. Shinogle Maria F. Owings Lola Jean Kozak 《Obesity (Silver Spring, Md.)》2005,13(12):2202-2209
Objective: This paper describes national trends in gastric bypass procedures from 1998 through 2003 and explores the demographic and health profile of those who receive this procedure. Short‐term outcomes such as length of stay and in‐hospital complication rates are also examined. Research Methods and Procedures: Data on obese hospital inpatients who had gastric bypass were obtained from the 1998 to 2003 National Hospital Discharge Survey. Gastric bypass was reported for an estimated 288,000 discharges during the 6‐year study period. Trends within the 6‐year period were tested using weighted regression. Characteristics of gastric bypass patients were compared with those of other inpatients using a χ2 test of independence and the two‐sided t test. Results: The estimated number of hospital discharges with gastric bypass increased significantly, from 14,000 in 1998 to 108,000 in 2003. During this period, the average length of stay declined by 56% from 7.2 to 3.2 days. Gastric bypass patients were primarily women (84%), 25 to 54 years of age (82%), and privately insured (76%). A 1 in 10 complication rate was found for discharges with gastric bypass. Discussion: Gastric bypass procedures in the United States have increased rapidly since 1998, whereas the average hospital stay has decreased. The decreasing length of stay needs to be evaluated in conjunction with potential complication rates and the permanent change in anatomy and lifestyle that must accompany this procedure. Monitoring trends in use of this procedure is important, especially if reimbursement policies change and the epidemic of obesity continues. 相似文献
13.
Extensive fires in recent decades in the Greater Yellowstone Ecosystem (GYE) garnered much attention for causing a significant
decrease in the extent of conifer forest cover. Meanwhile, conifer forests in unburned parts of the GYE have continued to
increase in extent and density. Conifer cover increase has been well documented by repeat historical photography, but the
average rate of increase and the spatial variation remain unquantified. We examined changes in conifer cover across biophysical
gradients in the GYE based on stratified random samples from aerial photographs. The percent conifer cover for samples in
1971 and 1999 was quantified to determine the frequency and rate of conifer cover change. A slight majority of samples (56%)
showed no change, whereas increases (22%) were balanced by decreases (22%). However, among samples that were not recently
burned or logged, or already closed-canopy, nearly 40% increased in conifer cover, at an average annual rate of 0.22%. We
quantified significant variability in the frequency and rate of conifer cover increase across gradients of elevation, aspect,
vegetation type, and proximity to nearby conifer forest. The most dynamic locations were low density conifer woodlands on
northerly aspects at lower elevations, with average annual rates of increase up to 0.51%. This study is significant because
it demonstrates that rates of conifer cover increase vary across biophysical gradients, an important consideration for management
of dynamic forest ecosystems. Improved understanding of this variability helps us to better understand what factors ultimately
cause conifer cover increase. It is also a critical step towards accurate quantification of the magnitude of carbon uptake
by conifer cover increase. 相似文献
14.
Louisa S. Evans Christina C. Hicks Pedro Fidelman Renae C. Tobin Allison L. Perry 《Human ecology: an interdisciplinary journal》2013,41(6):841-857
Climate change is a significant future driver of change in coastal social-ecological systems. Our knowledge of impacts, adaptation options, and possible outcomes for marine environments and coastal industries is expanding, but remains limited and uncertain. Alternative scenarios are a way to explore potential futures under a range of conditions. We developed four alternative future scenarios for the Great Barrier Reef and its fishing and tourism industries positing moderate and more extreme (2–3 °C above pre-industrial temperatures) warming for 2050 and contrasting ‘limited’ and ‘ideal’ ecological and social adaptation. We presented these scenarios to representatives of key stakeholder groups to assess the perceived viability of different social adaptation options to deliver desirable outcomes under varied contexts. 相似文献
15.
Catherine Boivin Ibrahima Ndoye Flore Molouba Philippe de Lajudie Nicolas Dupuy Bernard Dreyfus 《植物科学评论》1997,16(1):1-30
Rhizobia can establish a nitrogen-fixing symbiosis with plants of the Leguminosae family. They elicit on their host plant the formation of new organs, called nodules, which develop on the roots. A few aquatic legumes, however, can form nodules on their stem at dormant root primordia. The stem-nodulating legumes described so far are all members of the genera Aeschynomene, Sesbania, Neptunia, and Discolobium. Their rhizobial symbionts belong to four genera already described: Rhizobium, Bradyrhizobium, Sinorhizobium, and Azorhizobium. This review summarizes our current knowledge on most aspects of stem nodulation in legumes, the infection process and nodule development, the characterization and unusual features of the associated bacteria, and the molecular genetics of nodulation. Potential use as green manure in lowland rice of these stem-nodulating legumes, giving them agronomical importance, is also discussed. 相似文献
16.
The fatty acids of the progenies arising from the first back-crossfrom Elaeis guineensis and Elaeis oleifera interspecific hybridsto E. guineensis have been characterized. Fatty-acid patternsshowed striking variability which indicated that factors governingfatty-acid inheritance are polygenic. Although segregation forindividual fatty acids had no relationship with the large numberof morphological characters observed, a definite upward trendin the percentage of unsaturated fatty acids was clearly showncompared to the parent palms. The commercial and domestic advantagesof unsaturated fatty acids are discussed. Elaeis guineensis, oil palm, breeding, fatty acid content 相似文献
17.
Sizulu Moyo Helen S. Cox Jennifer Hughes Johnny Daniels Leigh Synman Virginia De Azevedo Amir Shroufi Vivian Cox Gilles van Cutsem 《PloS one》2015,10(3)
Background
A community based drug resistant tuberculosis (DR-TB) program has been incrementally implemented in Khayelitsha, a high HIV and TB burden community in South Africa. We investigated loss from treatment (LFT), and post treatment outcomes of DR-TB patients in this setting.Methodology
LFT, defined as interruption of treatment for ≥2 consecutive months was assessed among patients initiating DR-TB treatment for the first time between January 2009 and July 2011. Patients were traced through routine data sources to identify those who subsequently restarted treatment and those who died. Additional information on patient status and survival after LTF was obtained from community DR-TB counselors and from the national death registry. Post treatment outcomes were observed until July 2013.Results
Among 452 patients initiating treatment for the first time within the given period, 30% (136) were LFT, with 67% retention at 18 months. Treatment was restarted in 27 (20%) patients, with additional resistance recorded in 2/25 (8%), excluding two with presumed DR-TB. Overall, 34 (25%) patients died, including 11 who restarted treatment. Males and those in the age category 15-25 years had a greater hazard of LFT; HR 1.93 (95% CI 1.35-2.75), and 2.43 (95% CI 1.52-3.88) respectively. Older age (>35 years) was associated with a greater hazard of death; HR 3.74 (1.13- 12.37) post treatment. Overall two-year survival was 62%. It was lower (45%) in older patients, and was 92% among those who received >12 months treatment.Conclusion
LFT was high, occurred throughout the treatment period and was particularly high among males and those aged 15-25 years. Overall long term survival was poor. High rates of LFT should however not preclude scale up of community based care given its impact in increasing access to treatment. Further research is needed to support retention of DR-TB patients on treatment, even within community based treatment programs. 相似文献18.
Escherichia coli Mutants Lacking All Possible Combinations of Eight Penicillin Binding Proteins: Viability, Characteristics, and Implications for Peptidoglycan Synthesis
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Sylvia A. Denome Pamela K. Elf Thomas A. Henderson David E. Nelson Kevin D. Young 《Journal of bacteriology》1999,181(13):3981-3993
The penicillin binding proteins (PBPs) synthesize and remodel peptidoglycan, the structural component of the bacterial cell wall. Much is known about the biochemistry of these proteins, but little is known about their biological roles. To better understand the contributions these proteins make to the physiology of Escherichia coli, we constructed 192 mutants from which eight PBP genes were deleted in every possible combination. The genes encoding PBPs 1a, 1b, 4, 5, 6, and 7, AmpC, and AmpH were cloned, and from each gene an internal coding sequence was removed and replaced with a kanamycin resistance cassette flanked by two res sites from plasmid RP4. Deletion of individual genes was accomplished by transferring each interrupted gene onto the chromosome of E. coli via lambda phage transduction and selecting for kanamycin-resistant recombinants. Afterwards, the kanamycin resistance cassette was removed from each mutant strain by supplying ParA resolvase in trans, yielding a strain in which a long segment of the original PBP gene was deleted and replaced by an 8-bp res site. These kanamycin-sensitive mutants were used as recipients in further rounds of replacement mutagenesis, resulting in a set of strains lacking from one to seven PBPs. In addition, the dacD gene was deleted from two septuple mutants, creating strains lacking eight genes. The only deletion combinations not produced were those lacking both PBPs 1a and 1b because such a combination is lethal. Surprisingly, all other deletion mutants were viable even though, at the extreme, 8 of the 12 known PBPs had been eliminated. Furthermore, when both PBPs 2 and 3 were inactivated by the beta-lactams mecillinam and aztreonam, respectively, several mutants did not lyse but continued to grow as enlarged spheres, so that one mutant synthesized osmotically resistant peptidoglycan when only 2 of 12 PBPs (PBPs 1b and 1c) remained active. These results have important implications for current models of peptidoglycan biosynthesis, for understanding the evolution of the bacterial sacculus, and for interpreting results derived by mutating unknown open reading frames in genome projects. In addition, members of the set of PBP mutants will provide excellent starting points for answering fundamental questions about other aspects of cell wall metabolism. 相似文献
19.
Long-Term Waterlogging: Nutrient,Gas Exchange,Photochemical and Pigment Characteristics of Eucalyptus nitens Saplings 总被引:4,自引:0,他引:4
Imposition of waterlogging for eight months induced morphological adaptation in Eucalyptus nitens in the form of adventitious and aerenchymatous roots and hypertrophy of stems. Foliar calcium (1.3-fold), potassium (2-fold) and phosphorus (2.4-fold) were lower and iron (5.6-fold) was higher in waterlogged than control saplings. Stem Ca (1.7-fold) was lower, whereas Mn (1.8-fold) and Fe (117-fold) were higher in waterlogged than control saplings. Distinct purple pigmentation was observed in xylem tissues of waterlogged saplings. A significant reduction in the maximum photosynthetic rate and photochemical efficiency was observed in waterlogged compared to control saplings. Although chlorophyll levels were similar, the xanthophyll cycle pool size was significantly greater in waterlogged saplings and may have contributed to the relatively greater capacity for light energy dissipation observed. Predawn xanthophyll cycle engagement was significantly greater in waterlogged than control saplings, despite relatively mild temperatures. Foliar anthocyanin concentration was higher in waterlogged than control saplings. 相似文献
20.
In order to define the ancestors of the Eurasian genera Axis and Rusa, the representatives of the tribe Pliocervini have been reviewed, with the exclusion of the genus Pliocervus. The fossil remains referred to Pliocervini stored in the Palaeontological Museum of Mechnikov Odessa National University and studied by Khomenko [Khomenko, I., 1913. Meotian fauna of v. Tarakliya of Bendery district. Annuaire géologique et minéralogique de la Russie. 1. The ancestors of modern and fossil Cervinae. 2. Giraffidae and Cavicornia 15, 107-132 (in Russian)] are reappraised: these remains are attributed to Cervavitus novorossiae (Khomenko, 1913). The fossil deer collected from the locality of Novoelizavetovka (Odessa region, Ukraine) and observed in the same Museum of the Odessa National University, is referred to Cervavitus variabilis Alexeev (1915).The fossil material from Shanxi and Honan provinces (China), described by Zdansky [Zdansky, O., 1925. Fossil Hirsche Chinas. Palaeontologia Sinica C 2, 1-94] and Teilhard de Chardin and Trassaert [Teilhard de Chardin, P., Trassaert, M., 1937. The Pliocene Camelidae, Giraffidae and Cervidae of southeastern Shansi.] is referred to Cervavitus shanxius Dong and Hu, 1994. The phylogenetic relationships between Pliocervini from China and the European ones are investigated on the basis of the morphological, biochronological and paleogeographical data. These elements and the suggestions of the more recent genetical and biometrical data may indicate that the origin of the two genera Axis and Rusa could be recognized into the Chinese pliocervines. 相似文献