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1.
This article presents the results of studies on the pyrenes of selected European brambles belonging to different subgenera and sections of the genus Rubus. Differences between the pyrenes of particular species are mainly visible in their shape, size and the outer endocarp sculpture. Numerous SEM photographs revealed that the differentiation of the endocarp surface is due to variations in a thin layer of transition sclereids developing between the outer endocarp and a mesocarp parenchyma. The endocarp structure of the genus Rubus can be used in determining some species belonging to different subgenera, even if generally its significance in the taxonomy of the European Rubus is limited.  相似文献   
2.
DNA ligase IV (LigIV) deficiency was identified as the molecular basis for a severe form of combined immunodeficiency in two microcephalic siblings with cellular radiosensitivity. In one patient the diagnosis was made directly after birth, allowing analysis of the role of LigIV in the development of specific immune cells. Absolute numbers of B cells were reduced 100-fold and alphabeta T cells 10-fold, whereas gammadelta T cells were normal. Spectratyping of all three cell populations showed a diverse repertoire, but sequencing of IgH V(D)J junctions revealed shorter CDR3 regions due to more extensive nucleotide deletions among D and J elements and fewer N nucleotide insertions. Clonal restriction of IgG-expressing, but not IgM-expressing, B cells and the lack of primary and secondary lymph node follicles indicated impaired class switch recombination. Observations in the older sibling showed that this rudimentary immune system was able to mount specific responses to infection. However, partial Ab responses and extensive amplification of gammadelta T cells could not prevent a life-threatening course of viral and bacterial infections, the development of an EBV-induced lymphoma, and immune dysregulation reflected by severe autoimmune cytopenia. Impaired generation of immune diversity under conditions of limited LigIV activity can cause a human SCID variant with a characteristic immunological phenotype.  相似文献   
3.
4.
Galls formed by the interaction of insects on plant tissues are an example of the unusual transformation and use of plants by insects. The aim of this study was to characterize the structure of galls formed by Cynips quercusfolii L. on sessile oak leaves. In the structure of galls, we distinguished the following: (1) the protective ‘first contact zone’ created by epidermal and sub-epidermal sclerenchyma rings, (2) the wide parenchymatous ring, (3) the internal protective zone created by the sclerenchyma ring, and (4) the nutritional zone consisting of cells filled with amyloplasts containing starch. A characteristic for galls in the development stage is the centripetal starch gradient in which starch accumulates in a ‘ring of amyloplasts’ in the larval chamber.  相似文献   
5.
Context: Cardiogenic shock (CS) still remains one of the main causes of death in acute myocardial infarction (AMI).

Objective: The aim of this study was to evaluate the prognostic value of midregional (MR)-proadrenomedullin in AMI complicated by CS.

Methods: Forty-seven consecutive patients were included in our prospective observational study. All patients underwent coronarography and successful percutaneous coronary intervention (PCI). Plasma levels of MR-proADM were measured by a immunofluorescence method. The primary endpoint of the study, defined as cardiovascular death, occurred in 17 patients (36%).

Results and conclusion: Elevated plasma level of MR-proADM, determined 24?h after diagnosis of CS could be a predictor of in-hospital mortality in patients with AMI complicated by CS.  相似文献   

6.
In 6-year-old seeds of Brassica napus the columella cells haveno necroses and resemble in structure the cells of the 2-year-oldembryo. The outermost layer of the columella shows a structuresimilar to that of the lateral region of the root cap, as itcontains protein bodies, rare in layers of the columella closerto the promeristem, which, in turn, contain numerous mitochondriaand plastids. Phenolic compounds in the dry embryo are on thesurface of the root cap in the space between the plasmalemmaand the cell wall, and in small vesicles which presumably remainedfrom degradation of ER. Imbibition promotes further extrusionof phenolics outside the plasma membrane. Long sheets of ERare visible after 9 h imbibition. After 24 h phenolics of moredense structure are localized in some dilated parts of the ER.This suggests that new production of defence compounds startswithin 24 h in water, a few hours earlier than in 2-year-oldseeds.Copyright 1994, 1999 Academic Press Brassica napus, phenolics, root columella, germination  相似文献   
7.
Mucha J  Guzicka M  Lakomy P  Zadworny M 《Planta》2012,236(4):975-988
Defence mechanisms in trees are not well understood. We assessed whether distribution of iron ions and their co-localisation with reactive oxygen species in Pinus sylvestris root cells reflect differential preferences of the pathogens Heterobasidion annosum sensu stricto, H. parviporum and H. abietinum to the host. Strains of H. annosum s.s. characterised by a greater preference for P. sylvestris induced accumulation of superoxide (O(2) (-)) in host cells 6?h after inoculation, whereas two peaks in accumulation of O(2) (-) (after 4 and 48?h) were observed after infection with strains of the pathogens H. parviporum and H. abietinum, which have a lower preference for P. sylvestris. Moreover, strains of H. annosum s.s. caused increased production of hydrogen peroxide (H(2)O(2)) in P. sylvestris cells, in contrast with strains of the other two species (H. parviporum and H. abietinum). Following inoculation with H. annosum s.s. strains, H(2)O(2) was correlated negatively with O(2) (-) and correlated positively with ferrous iron (Fe(2+)). Co-localisation of Fe(3+) with H(2)O(2) may suggest that they are involved in inducing hypersensitive responses and eventually cell death in roots inoculated with H. annosum s.s. strains, in contrast with H. parviporum, in which other mechanisms operate when the host is parasitised.  相似文献   
8.
This paper presents the influence of penicillin, erythromycin, oxytetracycline and streptomycin on aquatic microorganisms isolated from three reservoirs with varied extent of environmental pollution (Sulej6w Reservoir, Zegrze Reservoir and Vistula River). The experiments were conducted in especially prepared microcosms (aerated 151 aquariums). From among the examined antibiotics streptomycin showed the longest activity in the water environment (27 days), followed by oxytetracycline (22 days). Erythromycin had 13 days activity while the penicillin only 4 days. The highest number of bacteria was observed in the Vistula, fewer in Zegrze Reservoir. Sulejów Reservoir was characterized by the lowest number of bacteria. The strains isolated from Sulej6w Reservoir were characterized by higher degree of biodiversity than those from Zegrze Reservoir or Vistula River. The dominant genera were Pseudomonas (49%), followed by Acinetobacter (21%), Flavomonas (9%), Alcaligenes (9%), Vibrio, Moraxella and Oligella. The Vistula River was dominated by Aeromonas (88%) and Pseudomonas (12%) genera. The strains isolated from Sulej6w Reservoir were more sensitive to antibiotics than those from the much more polluted Vistula, this being evidenced by lower MIC and MBC values.  相似文献   
9.
Both Staphylococcus epidermidis and Staphylococcus haemolyticus are important causes of infections associated with catheters and other medical devices. This infections result in significant morbidity, mortality and economic cost. It has recently been shown that not only S. epidermidis but also S. haemolyticus can produce slime and carries the ica operon responsible for and slime production. In the operon, coexpression of icaA and icaD is required for full slime synthesis. This study is focused on detecting icaA and icaD genes in S. haemolyticus and comparison of these two species. It turned out that strain representatives within the same species behave very differently and a single tested strain from each species is unlikely to be representative of the species as a whole. Contrary to S. epidermidis, S. haemolyticus strain appeared to carry no icaA-like and icaD-like genes, but was able to form biofilm in vitro.  相似文献   
10.
A surface adhesion is a fundamental stage, in a pathogenesis of inflammations caused by coagulase-negative staphylococci, at which surface proteins take part. The proteins that were found at S. saprophyticus and ascribed to take part in polystiren plates adhesion: SSP-1 and SSP-2 could be an example. In this work the effort to esteem surface protein expression of various kinds of coagulase-negative staphylococcus according to cultivation conditions has been made. The studies carried out with 31 staphylococcus strains being obtained from new-born children hospitalised in Neonatology Clinic helped to analyse the similarities among these proteins in the area of a given strain cultivated on different mediums. The examined strains belonged to five different species and it had been taken into consideration during the results esteem. On the grounds of electrophoretic surface proteins division the charts dysometric analysis was created showing interdependence between Rf for surface proteins and optical density. Afterwards an analysis for each strain was done taking into account a sort of medium on which the cultivation had been placed. S. haemolyticus strains analysis cultivated on three different mediums allows to isolate two protein groups showing similar expression of both low- and high-molecular proteins. For the majority of strains belonging to the same species one can observe a similar expression within low- and high-molecular surface proteins regardless of cultivation conditions. Recurrence of the electrophoretic pictures regardless of changes in cultivation conditions, creates the base for the recognised proteins identification and also for the proteins with unmarked activity isolation.  相似文献   
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