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81.
Summary A bimodal temperature response is observed in the germination of seeds in Jussiaea suffruticosa, both under continuous and cyclic light treatments. Germination exhibits two maxima at around 25° C and at 40°, and a minimum in the region of 30–35°. The response depends on light intensity both under continuous and intermittent light treatments. This dependence is much more noticeable in the region of minimum germination (30°). Both preincubation in darkness at 35° and high light intensities (15 500 lux) tend to eliminate the bimodal temperature response. 相似文献
82.
A novel insertion 78,ZZ or 78,ZW, ins(3;1)(q25q27;undetermined) was revealed in chicken by double color fluorescent in situ hybridization (FISH). A fragment of chromosome 1 spanning either from q13-14 to q34-35, or from q14-21 to q36-41 bands, had been translocated to chromosome 3 at a site located between q25 to q27 bands. This has resulted in the generation of an interstitial deletion in chromosome 1 and an insertional translocation in chromosome 3. Chickens with this balanced insertional translocation are asymptomatic carriers and their fertility is not affected, but embryo mortality increases. Greater than 50% occurrence of unbalanced gametes are observed. However, progeny sex ratio is not affected. 相似文献
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Pérez-Pérez JM Rubio-Díaz S Dhondt S Hernández-Romero D Sánchez-Soriano J Beemster GT Ponce MR Micol JL 《Plant, cell & environment》2011,34(12):2200-2211
Despite the large number of genes known to affect leaf shape or size, we still have a relatively poor understanding of how leaf morphology is established. For example, little is known about how cell division and cell expansion are controlled and coordinated within a growing leaf to eventually develop into a laminar organ of a definite size. To obtain a global perspective of the cellular basis of variations in leaf morphology at the organ, tissue and cell levels, we studied a collection of 111 non-allelic mutants with abnormally shaped and/or sized leaves, which broadly represent the mutational variations in Arabidopsis thaliana leaf morphology not associated with lethality. We used image-processing techniques on these mutants to quantify morphological parameters running the gamut from the palisade mesophyll and epidermal cells to the venation, whole leaf and rosette levels. We found positive correlations between epidermal cell size and leaf area, which is consistent with long-standing Avery's hypothesis that the epidermis drives leaf growth. In addition, venation parameters were positively correlated with leaf area, suggesting that leaf growth and vein patterning share some genetic controls. Positional cloning of the genes affected by the studied mutations will eventually establish functional links between genotypes, molecular functions, cellular parameters and leaf phenotypes. 相似文献
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Morphology of Nyctotheroides hubeiensis Li et al. 1998 from Frog Hosts with Molecular Phylogenetic Study of Clevelandellid Ciliates (Armophorea,Clevelandellida) 下载免费PDF全文
Ming Li Zong‐Yi Sun J. Norman Grim Francisco Ponce‐Gordo Gui‐tang Wang Hong Zou Wen‐xiang Li Shan‐gong Wu 《The Journal of eukaryotic microbiology》2016,63(6):751-759
The morphology of Nyctotheroides hubeiensis (Acta Hydrobiol. Sin. 1998, 22(suppl.):187), collected from the rectum of Phelophylax nigromaculatus, is presented in this paper based on detailed morphological information and molecular data. Our phylogenetic analysis showed that N. hubeiensis fell into the Nyctotheroides clade, which was strongly supported as monophyletic and clustered as basal to the genera Nyctotherus and Clevelandella. Also, the monophyly of the Order Clevelandellida and the affinity of parasitic nyctotherids and free‐living metopids were indicated in our work. The origin of clevelandellid ciliates as well as their possible evolutionary history was also discussed here; however, the analysis of more species from other vertebrate hosts (fish, reptiles) should be made before a well‐supported conclusion can be drawn. 相似文献
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Peritoneal dialysis (PD) should be considered a suitable method of renal replacement therapy in acute kidney injury (AKI) patients. This study is the largest cohort providing patient characteristics, clinical practice, patterns and their relationship to outcomes in a developing country. Its objective was to describe the main determinants of patient and technique survival, including trends over time of PD treatment in AKI patients. This was a Brazilian prospective cohort study in which all adult AKI patients on PD were studied from January/2004 to January/2014. For comparison purposes, patients were divided into 2 groups according to the year of treatment: 2004-2008 and 2009-2014. Patient survival and technique failure (TF) were analyzed using the competing risk model of Fine and Gray. A total of 301 patients were included, 51 were transferred to hemodialysis (16.9%) during the study period. The main cause of TF was mechanical complication (47%) followed by peritonitis (41.2%). There was change in TF during the study period: compared to 2004-2008, patients treated at 2009-2014 had relative risk (RR) reduction of 0.86 (95% CI 0.77 – 0.96) and three independent risk factors were identified: period of treatment at 2009 and 2014, sepsis and age> 65 years. There were 180 deaths (59.8%) during the study. Death was the leading cause of dropout (77.9% of all cases) mainly by sepsis (58.3%), followed cardiovascular disease (36.1%). The overall patient survival was 41% at 30 days. Patient survival improved along study periods: compared to 2004-2008, patients treated at 2009-2014 had a RR reduction of 0.87 (95% CI 0.79 – 0.98). The independent risk factors for mortality were sepsis, age >70 years, ATN-ISS > 0.65 and positive fluid balance. As conclusion, we observed an improvement in patient survival and TF along the years even after correction for several confounders and using a competing risk approach. 相似文献
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Expression,Functionality, and Localization of Apurinic/Apyrimidinic Endonucleases in Replicative and Non‐Replicative Forms of Trypanosoma cruzi 下载免费PDF全文