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The genetic diversity within and among populations of Shorea leprosula and Shorea parvifolia from Indonesia was investigated using amplified fragment length polymorphisms (AFLPs). The results indicated that S. leprosula is genetically more variable than S. parvifolia. At the population level, a higher level of genetic diversity was revealed for S. leprosula with a percentage of polymorphic loci (PPLp) of 53.32% and an expected heterozygosity (H ep) of 0.16 in comparison with S. parvifolia showing PPLp of 51.79% and H ep of 0.14. At the species level, S. leprosula showed PPLs of 92.86% and H es of 0.21, while S. parvifolia showed PPLs of 85.71% and H es of 0.21. Genetic differentiation (G st) indicated that 25 and 31% of total genetic diversity in S. leprosula and S. parvifolia, respectively, were attributed to the differences among populations. An analysis of molecular variance (AMOVA) at two hierarchical levels exhibited that most genetic variation resided within populations with proportion of 70.2% for S. leprosula and 66.2% for S. parvifolia. The AMOVA at three hierarchical levels performed for S. leprosula and S. parvifolia together revealed that the genetic difference between the two species was remarkably higher with a proportion of 44.1% than the differences within and among populations (38.1 and 17.8%, respectively). The genetic differentiation between islands was significant for S. leprosula but not for S. parvifolia. The observed genetic diversity agreed with the life history traits of Shorea species. Highly differentiating individual AFLP markers were found for each species, which will serve as diagnostic markers for the identification of wood of different species, from different islands and regions.  相似文献   
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The anti-malarial agent atovaquone specifically targets the cytochrome bc1 complex and inhibits the parasite respiration. Resistance to this drug, a coenzyme Q analogue, is associated with mutations in the mitochondrial cytochrome b gene. We previously reported atovaquone resistant mutations in Plasmodium berghei, in the first quinone binding domain (Qo1) of the cytochrome b gene (M133I and L144S) with V284F in the sixth transmembrane domain. However, in P. falciparum the most common mutations are found in the Qo2 region. To obtain a better model for biochemical and genetic studies, we have now extended our study to isolate a wider range of P. berghei resistant strains, in particular those in the Qo2. Here we report four new mutations (Y268N, Y268C, L271V and K272R), all in the Qo2 domain. Two of these mutations are convergent to codon 268 (nt802–804) drug-induced mutation in P. falciparum.  相似文献   
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Shorea is the largest and most important genus of the Dipterocarpaceae. The genetic diversity and structure of nine Shorea species from two different locations, namely Nanjak Makmur in Sumatra and Sumalindo in Borneo, were evaluated using amplified fragment length polymorphism (AFLP) markers. A total of 274 trees were investigated at 85 polymorphic AFLP loci. Levels of genetic diversity of these species ranged from  = 0.100 for S. acuminata to  = 0.165 for S. blumutensis. The population of rare species S. blumutensis possessed the highest genetic diversity suggesting that geographically restricted species can have levels of genetic variation comparable to closely related widespread common congeners. Analyses of molecular variance revealed that the genetic variation was mainly found among species in both locations (57.7% in Sumatra; 56.3% in Borneo). The unweighted pairgroup method using arithmetic averages dendrogram of all samples revealed an almost complete separation of species. Thus, AFLP markers proved appropriate for phylogenetic studies of Shorea species. Specific markers have been detected showing high-frequency differences among species and between regions within species. Sequence information of these markers can be used to develop specific polymerase chain reaction markers for wood identification. The possibility of interspecific hybridization was discussed.  相似文献   
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Background/Objectives. Therapy for Hodgkin’s lymphoma is disease specific and cannot be compared with treatment for other diseases. It often includes more extensive radiotherapy on the mediastinum than for other malignancies. Cardiac morbidity is known to occur in patients previously irradiated. This study describes the postoperative course after cardiac surgery of patients previously irradiated for Hodgkin’s lymphoma. Methods. From January 1990 until June 2008, 12 patients underwent cardiac surgery in the University Medical Center Utrecht after previous irradiation for Hodgkin’s lymphoma. Data on radiotherapy, surgery and follow-up were collected retrospectively. The postoperative functional status was assessed by a telephone questionnaire. Results. Atrial fibrillation (33%) and pleural effusion (25%) were the most common postoperative complications. After a mean followup of 2.6±2.9 years four patients had died. The remaining patients were all in a favourable New York Heart Association and Canadian Cardiothoracic Society class. The estimated one-, two- and four-year survival rates were 83, 69 and 46% respectively. Conclusion. The early postoperative outcome of cardiac surgery in this population is reasonably good. The long-term results may prove to be disappointing, but the cohort is small. (Neth Heart J 2010;18:61–5.)  相似文献   
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It is a well-known phenomenon that some patients with acute left or right hemisphere stroke show a deviation of the eyes (Prévost's sign) and head to one side. Here we investigated whether both right- and left-sided brain lesions may cause this deviation. Moreover, we studied the relationship between this phenomenon and spatial neglect. In contrast to previous studies, we determined not only the discrete presence or absence of eye deviation with the naked eye through clinical inspection, but actually measured the extent of horizontal eye-in-head and head-on-trunk deviation. In further contrast, measurements were performed early after stroke onset (1.5 days on average).  相似文献   
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In this review we discuss cardiovascular mortality, incidence and prevalence of heart disease, and cardiac interventions and surgery in the Netherlands. We combined most recently available data from various Dutch cardiovascular registries, Dutch Hospital Data (LMR), Statistics Netherlands (CBS), and population-based cohort studies, to provide a broad quantitative update. The absolute number of people dying from cardiovascular diseases is declining and cardiovascular conditions are no longer the leading cause of death in the Netherlands. However, a substantial burden of morbidity persists with 400,000 hospitalisations for cardiovascular disease involving over 80,000 cardiac interventions annually. In the Netherlands alone, an estimated 730,000 persons are currently diagnosed with coronary heart disease, 120,000 with heart failure, and 260,000 with atrial fibrillation. These numbers emphasise the continuous need for dedicated research on prevention, diagnosis, and treatment of heart disease in our country.  相似文献   
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Distribution of tropical rainforests in Southeastern Asia has changed over geo-logical time scale, due to movement of tectonic plates and/or global climatic changes. Shorea parvifolia is one of the most common tropical lowland rainforest tree species in Southeastern Asia. To infer population structure and demographic history of S. parvifolia, as indicators of temporal changes in the distribution and extent of tropical rainforest in this region, we studied levels and patterns of nucleotide polymorphism in the following five nuclear gene regions: GapC, GBSSI, PgiC, SBE2, and SODH. Seven populations from peninsular Malaysia, Sumatra, and eastern Borneo were included in the analyses. STRUCTURE analysis revealed that the investigated populations are divided into two groups: Sumatra-Malay and Borneo. Furthermore, each group contained one admixed population. Under isolation with migration model, divergence of the two groups was estimated to occur between late Pliocene (2.6 MYA) and middle Pleistocene (0.7 MYA). The log-likelihood ratio tests of several demographic models strongly supported model with population expansion and low level of migration after divergence of the Sumatra-Malay and Borneo groups. The inferred demographic history of S. parvifolia suggested the presence of a scarcely forested land bridge on the Sunda Shelf during glacial periods in the Pleistocene and predominance of tropical lowland rainforest at least in Sumatra and eastern Borneo.  相似文献   
10.
Protein patterns of callus from corn (Zea mays L.) inbreds that are either resistant or susceptible to fall armyworm (Spodoptera frugiperda [J.E. Smith]) were analyzed by two-dimensional electrophoresis. Fall armyworm larvae reared on callus initiated from resistant inbreds were significantly smaller than those reared on callus of susceptible inbreds. A 33-kD protein found in callus from the resistant inbreds Mp704 and Mp708 was absent in callus from the susceptible inbreds Tx601 and Ab24E. However, a 36-kD protein found in Ab24E callus immunoreacted with polyclonal antibody raised against the 33-kD protein. When Mp704 nonfriable callus changed to friable, larval growth was not inhibited and the 33-kD protein was absent. There was a significant negative correlation between the concentration of the 33-kD protein in the callus and the weight of the larvae feeding on the callus in the F2 progeny of Mp704 x Tx601. The N-terminal amino acid sequence of the 33-kD protein suggested that it was cysteine proteinase. Purification of the 33- (Mp708) and 36-kD (Ab24E) proteins indicated that they were both cysteine proteinases. The 33-kD cysteine proteinase had 7-fold higher specific activity than the 36-kD enzyme.  相似文献   
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