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111.
112.
A new smut fungus Ustilago aldabrensis on the grass Dactyloctenium ctenoides is described and illustrated from Aldabra Island in the Seychelles archipelago. It is compared with similar species known
on the genus Dactyloctenium. A further two smut fungi infecting this host plant genus, U. dactyloctenii-gigantei and U. idonea are discussed. U. dactyloctenii-gigantei is reported for the first time from Nigeria on a new host plant, D. aegyptium. U. idonea is redescribed, and its nomenclature and geographical distribution are clarified. A key to smut fungi infecting species of
Dactyloctenium is provided. 相似文献
113.
Capsule Although the White Stork avoids adverse weather conditions by modifying its arrival and breeding, it cannot avoid extreme weather events during the breeding season.Aims To show how extreme weather conditions can influence breeding attempts of a large, long-lived species, the White Stork.Methods We analysed data on arrivals of White Storks in Western Poland from 2005 to 2013 and detailed breeding biology parameters from 2009 to 2013 in relation to weather conditions. We analysed breeding success and breeding failure rate from 1974 to 2013.Results In years with a cold March White Storks arrived later than when March was warmer. Frost during incubation negatively influenced the hatching success. Extreme weather events caused high late mortality even for nestlings older than 30 days. Data from 27 breeding seasons showed a significant increase in mean breeding success but also a significant increase in the proportion of pairs which lost broods in the nestling stage.Conclusion The White Stork can modify its arrival in response to current weather conditions on the breeding grounds but it cannot respond to extreme weather events. Due to increasing frequency of extreme weather events caused by climate change, White Stork breeding success may decrease in the future. 相似文献
114.
J Mirecka J Libura M Libura M Koprowski D Nowak B Kedra T Popiela 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2001,39(4):335-340
The aim of this study was to evaluate angiogenesis in tissue of the pancreatic ductal adenocarcinoma and to correlate it with histopathological data such as tumour differentiation, tumour size, lymph node metastasis and patients survival. Tumour samples obtained during surgery from 36 patients were immunostained for the presence of blood vessels with monoclonal antibody against the CD31 molecule. Evaluation of microvasculature was perfomed by counting the microvessel density (MVD) in selected areas under light microscope as well as by computer assisted image analysis (CAIA). In the latter, the following parameters were used for assessment of microvessels: mean number/field, mean area of the vessels, total area/field and total perimeter/field. MVD values obtained under optical microscope and with CAIA were highly correlated. All parameters characterising microvasculature in CAIA also revealed a significant correlation with the histological grading of tumours; generally the less differentiated tumours manifested more extensive vascular network. No significant relationship was found between the tumour size and any of the CAIA parameters. The area of vessels (both total and mean values) revealed a significant, inverse correlation with the incidence of lymph node metastases. The same type of correlation was also found between the mean vessel area and the postoperative survival period. The results show that CAIA of microvessels offers new parameters with some predictive value for the outcome of patients with pancreatic cancer. 相似文献
115.
116.
The members of the smut genus Microbotryum are pathogens of a wide range of host plant species from nine dicotyledonous families. Within the genus, the species sporulating in anthers of Caryophyllaceae form a monophyletic group that in recent years attracted much interest in various biological studies. The phylogenetic framework developed for species delimitation within Microbotryum revealed that high level host-specificity is a major feature of most caryophyllaceous anther smuts. However, the great number of anther smut specimens on diverse host plant species reported worldwide has still not been included in phylogenetic analyses due to the inaccessibility of recently collected specimens, and thus many species remain still undiscovered. In this study, anther smut specimens on Heliosperma pusillum originating from all main mountain ranges of the European Alpine System were examined using partial rDNA sequence and/or morphological analyses. The investigation revealed that all specimens are morphologically uniform and phylogenetically represent a monophyletic lineage, sister to Microbotryum lagerheimii complex on Atocion rupestre/Silene lacera/Silene vulgaris/Viscaria vulgaris. This lineage cannot be attributed to any of the previously described species, and therefore the smut in anthers of H. pusillum is described and illustrated here as a new species, Microbotryum heliospermae. The species is known from subalpine zone of the Alps, the Carpathians, the Dinaric Alps, and the Pyrenees, inhabiting host plants growing in open spring communities or semihumid mountain meadows. 相似文献
117.
Beata S. Lipska Irena Balasz-Chmielewska Lucyna Morzuch Kacper Wasielewski Dominika Vetter Halina Borzecka Dorota Drozdz Agnieszka Firszt-Adamczyk Ewa Gacka Tomasz Jarmolinski Joanna Ksiazek Elzbieta Kuzma-Mroczkowska Mieczyslaw Litwin Anna Medynska Magdalena Silska Maria Szczepanska Marcin Tkaczyk Anna Wasilewska Franz Schaefer Aleksandra Zurowska Janusz Limon 《Journal of applied genetics》2013,54(3):327-333
Hereditary nephrotic syndrome is caused by mutations in a number of different genes, the most common being NPHS2. The aim of the study was to identify the spectrum of NPHS2 mutations in Polish patients with the disease. A total of 141 children with steroid-resistant nephrotic syndrome (SRNS) were enrolled in the study. Mutational analysis included the entire coding sequence and intron boundaries of the NPHS2 gene. Restriction fragment length polymorphism (RFLP) and TaqMan genotyping assay were applied to detect selected NPHS2 sequence variants in 575 population-matched controls. Twenty patients (14 %) had homozygous or compound heterozygous NPHS2 mutations, the most frequent being c.1032delT found in 11 children and p.R138Q found in four patients. Carriers of the c.1032delT allele were exclusively found in the Pomeranian (Kashubian) region, suggesting a founder effect origin. The 14 % NPHS2 gene mutation detection rate is similar to that observed in other populations. The heterogeneity of mutations detected in the studied group confirms the requirement of genetic testing the entire NPHS2 coding sequence in Polish patients, with the exception of Kashubs, who should be initially screened for the c.1032delT deletion. 相似文献
118.
Wolánski M Wali R Tilley E Jakimowicz D Zakrzewska-Czerwinska J Herron P 《Journal of bacteriology》2011,193(5):1273-1275
We observed movies of replisome trafficking during Streptomyces coelicolor growth. A replisome(s) in the spore served as a replication center(s) until hyphae reached a certain length, when a tip-proximal replisome formed and moved at a fixed distance behind the tip at a speed equivalent to the extension rate of the tip. 相似文献
119.
Heather E. Johnson Vernon C. Bleich Paul R. Krausman John L. Koprowski 《European Journal of Wildlife Research》2007,53(1):9-15
Although antler size has been identified as a primary determinant of dominance, fighting success, and reproductive success
in male cervids, >80% of the male tule elk (Cervus elaphus nannodes) in the Owens Valley, California, experience antler breakage. To determine the effect of antler breakage on male mating success,
we recorded antler morphology, body size, and mating behavior of male elk throughout the rut. Antler breakage, regardless
of severity, had no effect on male–male assessment, fighting success, or harem-holding status. The factor consistently associated
with our indices of male mating success was not antler size but body size. Although antler size is frequently emphasized as
a key factor in male dominance and social rank, this association may reflect the correlation between antler size and body
size. In the Owens Valley, it appears that male elk are not assessing competitors based on antler morphology but on other
characteristics.
An erratum to this article can be found at 相似文献
120.
Słuczanowska-Głabowska S Laszczyńska M Głabowski W Wylot M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2006,44(1):25-30
The effect of hyperprolactinemia on the prostate has not been well investigated. Since androgens play an important role in prostate development, growth and function, the goal of the present study was to estimate the influence of hyperprolactinemia on expression of the androgen receptor (AR) in rat epithelial cells of prostate dorsal lobe and on morphology of these cells. Studies were performed on sexually mature male Wistar rats. The experimental group rats received metoclopramide (MCP) intraperitoneally to provoke hyperprolactinemia. The control group animals were given saline in the same way. For light and electron microscopy the prostate dorsal lobes were obtained routinely. To evaluate the intensity of immunohistochemical reaction for AR in epithelial cells, the optical density was measured and computer-assisted image analysis system was used. Morphological observations of the dorsal lobe epithelial cells were carried out in transmission electron microscope. MCP caused over twofold increase in prolactin (PRL) serum levels. In rats with hyperprolactinemia, the testosterone levels (T) were twofold decreased. The intensity of immunohistochemical reaction for AR in epithelial cells of dorsal lobe in the experimental group was significantly lower than in the control group. In the dorsal lobe epithelial cells of experimental group animals, the transmission electron microscopy (TEM) revealed highly dilated RER cisternae and reduced number of microvilli on the cellular surface when compared to the control group. The results show that hyperprolactinemia in male rats causes morphological abnormalities in the dorsal lobe of prostate. The abnormalities are caused by elevated prolactin either directly or indirectly through decreased level of testosterone. Decreased expression of AR in epithelial cells of prostate dorsal lobe is likely to be caused by decreased testosterone level. 相似文献