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11.
The abundance and distribution of predatory cladoceran Leptodora kindtii was investigated in the estuarine lagoon (Curonian Lagoon, SE Baltic Sea). Three hydrodynamically different parts of the lagoon were selected, representing transitory oligohaline, intermediate freshwater and stagnant freshwater sites. L. kindtii was least abundant at the oligohaline site, never occurring at salinities greater than 4 psu. At the two freshwater sites, the abundance of L. kindtii varied from a low of <0.1 up to 2.2 indv. L−1 during peak abundance. Two peaks of L. kindtii abundance were observed with timing differences between stations: at the stagnant site the population of L. kindtii peaked two weeks earlier relative to the more hydrodynamically active sites, likely due to a 2°C higher May temperature. The small body size of L. kindtii in the lagoon (seasonal mean 2.68±0.6 mm) shows high fish predation pressure and predicts small cladocerans, juvenile copepods and rotifers being in the preferred prey size range. The calculated L. kindtii daily consumption during the population peak was as high as 100% of the daily zooplankton production, which implies high potential of this predator to shape the grazing zooplankton community in the lagoon.  相似文献   
12.
Ligand interactions are central to enzyme or receptor function, constituting a cornerstone in biochemistry and pharmacology. Here we discuss a ligand application that can be exploited to significantly increase the proportion of recombinant protein expressed in soluble form, by including ligands during the culture. Provided that a sufficiently soluble, cell-permeable and avid ligand is available, one can use it to stabilize nascently synthesized proteins, and in this manner promote solubility and prevent aggregation. To our knowledge, this concept has not been explored systematically and we provide here the first data on ligand supplementation in expression experiments across a whole human protein family: the short-chain dehydrogenases/reductases (SDR). We identified glycerrhitinic acid and its hemisuccinate ester, carbenoxolone (CBX), as ligands with variable affinities ranging from low nanomolar to micromolar binding constants against several SDRs. CBX was utilized as a culture additive in Escherichia coli expression systems against a total of approximately 500 constructs derived from 65 SDR targets, and significantly higher levels of soluble protein were obtained for more than four distinct targets. One of these, the glucocorticoid-activating enzyme type 1 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD1), was solubly expressed only at a very low level (<10 microg/l culture) in the absence of ligand; however, soluble expression could be enhanced to mg/l levels by inclusion of CBX or other inhibitors. Other compounds with different chemical scaffolds were used against 11 beta-HSD1 in equivalent expression experiments yielding similar results. Taken together, if suitable ligands for a given protein are available, this approach could be tested quickly and might represent an easy and effective strategy to enhance soluble protein production, suitable for structural and functional characterization studies.  相似文献   
13.
The goal of the research was to define experts opinion about adequate criteria for water polo players' actual quality evaluation and to determine experts opinion about weight coefficients (ponders) of the here defined criteria across the playing positions in the game of water polo. Based upon the expertise performed by ten water polo professionals, the relative importance coefficients with regard to playing positions in the game were determined for twenty seven performance evaluation criteria. High degree of interobserves' agreement was obtained regarding all positions (from 0.93 to 0.96). In concordance with the obtained results the particular playing positions were explicitly described, as well as the similarities and the differences between them were determined from the aspect of the single criteria importance. The research results could be usefully applied by the water polo practitioners for the selection and follow-up of players during training programme implementation, and for programming, control and evaluation of transformational effects.  相似文献   
14.
The aim of this study was to obtain the relevant information on antibiotic use in a 750-bed Croatian university hospital. The study has been designed as a 2-point prevalence interventional analysis. For each patient on antibiotic therapy, diagnosis, indication for treatment, antibiotic therapy, dosage and route of administration together with the results of microbiological studies (if available) were obtained. After the first prevalence analysis in 2001, a restriction on unlimited antibiotic use was introduced. The second analysis, performed in 2002, after restrictions on antibiotic use, revealed reductions in the rates of restricted release antibiotics and overall antibiotic use with decreases from 38.6% to 36.9% and 23.4% to 23.2% respectively (p = 0.87). The first survey showed that the 5 most often prescribed antibiotics in the therapy of bacterial infections were: gentamicin, other aminoglycosides, carbapenems, amoxycillin +clavulanate and vancomycin with proportions of 14.8%, 10.3%, 8.2%, 7% and 7% respectively. In the year 2002, the most prescribed antimicrobial drugs in the therapy of bacterial infections were: gentamicin, quinolones, vancomycin, carbapenems and cefuroxime with proportions of 18.6%, 11.4%, 9.7%, 9.3% and 8% respectively. A reduction in the proportions of doubtful antibiotic therapy, from 24.6% before the intervention, to 24.2% after the restrictions, accompanied by a 0.4% rise in the rates of indicated antibiotic therapy was also observed (p = 0.93). Our study shows that restrictions on formerly unlimited use of antimicrobials, even when leading to an improvement in their prescribing, do not necessarily cause rapid and significant reduction in the overall use of antibiotics or explicit positive financial effects.  相似文献   
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16.
Alpha-actinin 4 (ACTN4) is an actin-binding protein. In the cytoplasm, ACTN4 participates in structural organisation of the cytoskeleton via cross-linking of actin filaments. Nuclear localisation of ACTN4 has also been reported, but no clear role in the nucleus has been established. In this report, we describe the identification of proteins associated with ACTN4 in the nucleus. A combination of two-dimensional gel electrophoresis (2D-GE) and MALDI-TOF mass-spectrometry revealed a large number of ACTN4-bound proteins that are involved in various aspects of mRNA processing and transport. The association of ACTN4 with different ribonucleoproteins suggests that a major function of nuclear ACTN4 may be regulation of mRNA metabolism and signaling.  相似文献   
17.
As expected, since we recently celebrated the 250th anniversary of birth of Wolfgang Amadeus Mozart, there has been again a renewal of interest in his short but intensive life, as well as in the true reason of his untimely dead. Mozart lived and died in time when the medical knowledge was based mostly on subjective observations, without the established basics of standardized medical terminology and methodology. This leaves a great space for hypothesizing about his health problems, as well as about the cause of his death. The medical academic community attributed to Mozart approximately 150 different medical diagnoses. There is much speculation on the possible causes of Mozart's death: uremia, infection, rheumatic fever, trichinellosis, etc. Recently some authors have raised the question about a possible concomitant neurological disease. According to available records, Mozart has shown some elements of cyclotimic disorder, epilepsy and Gilles de la Tourette syndrome. Furthermore, the finding of a temporal fracture on (allegedly) Mozart's skull, gives a way to speculations about the possibility of a chronic subdural hematoma and its compressive effect on the temporal lobe. Despite numerous theories on Mozart's pathography that also include a concomitant neurological disorder, the medical and history records about Mozart's health status indicate that he probably had suffered from an infective illness, followed most likely by the reactivation of rheumatic fever, which was followed by strong immunologic reaction in the last days of his life. Taking all the above into consideration, it is reasonably to conclude that Mozart's neurological disturbances were caused by the intensity of the infective disease, and not primarily by a neurological disease.  相似文献   
18.
Understanding the control of myelin formation by oligodendrocytes is essential for treating demyelinating diseases. Neuregulin-1 (NRG1) type III, an EGF-like growth factor, is essential for myelination in the PNS. It is thus thought that NRG1/ErbB signaling also regulates CNS myelination, a view suggested by in vitro studies and the overexpression of dominant-negative ErbB receptors. To directly test this hypothesis, we generated a series of conditional null mutants that completely lack NRG1 beginning at different stages of neural development. Unexpectedly, these mice assemble normal amounts of myelin. In addition, double mutants lacking oligodendroglial ErbB3 and ErbB4 become myelinated in the absence of any stimulation by neuregulins. In contrast, a significant hypermyelination is achieved by transgenic overexpression of NRG1 type I or NRG1 type III. Thus, NRG1/ErbB signaling is markedly different between Schwann cells and oligodendrocytes that have evolved an NRG/ErbB-independent mechanism of myelination control.  相似文献   
19.
The research deals with experiencing infertility and its consequences in the adoption of a child and focuses on infertile couples that have wished to adopt a child and joined a program preparing them to be foster parents. The results show that most of the infertile couples experience infertility very much as being different from couples with children as well as having to cope with the feelings of deep emotional loss resulting from the inability to reproduce biologically. There is therefore the question whether these facts should be taken into account by the profession (i.e. social workers) when dealing with child adoption as, according to most of the respondents of our survey, the process of coming to terms with infertility and its consequences is an important factor in establishing healthy family relationships and the child's identity within the adoptive family. We concluded from the results of the research that the infertile couples preparation program for adopting a child carried out by the Society of Adoptive Families "Deteljica", is a comprehensive autopoietic social workers' answer to the needs of participants for a successful adoption of a child, as it makes it possible to supply these future adoptive parents with the requisite information and experience and provides support to the entire family upon accepting a child in its midst, while its fundamental attribute is offering help to couples in overcoming the traumas resulting from their infertility.  相似文献   
20.
The aim of the study was to assess forensic pertinence of 12 short tandem repeats (STRs) on X-chromosome in south Croatia population. Investigator® Argus X-12 kit was used to co-amplify 12 STR loci belonging to four linkage groups (LGs) on X-chromosome in 99 male and 98 female DNA samples of unrelated donors. PCR products were analyzed by capillary electrophoresis. Population genetic and forensic parameters were calculated by the Arlequin and POPTREE2 software, and an on-line tool available at ChrX-STR.org. Hardy–Weinberg equilibrium was confirmed for all X-STR markers in female samples. Biallelic patterns at DXS10079 locus were detected in four male samples. Polymorphism information content for the most (DXS10135) and the least (DXS8378) informative markers was 0.9212 and 0.6347, respectively. In both male and female samples, combined power of discrimination exceeded 0.999999999. As confirmed by linkage disequilibrium test, significant association of marker pair DXS10074-DXS10079 (P?=?0.0004) within LG2 and marker pair DXS10101-DXS10103 (P?=?0.0003) within LG3 was found only in male samples. Number of observed haplotypes in our sample pool amounted 3.01, 7.53, 5 and 3.25% of the number of possible haplotypes for LG1, LG2, LG3 and LG4, respectively. According to haplotype diversity value of 0.9981, LG1 was the most informative. In comparison of south Croatia with 26 world populations, pair-wise \({{\text{F}}_{\text{ST}}}^{\text{*}}\) values increase in parallel with geographical distance. Overall statistical assessment confirmed suitability of Investigator® Argus X-12 kit for forensic casework in both identification and familial testing in the population of south Croatia.  相似文献   
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