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41.
A population of grey wolvesCanis lupus Linnaeus, 1758 inhabiting Bia?owie?a Primeval Forest (BPF) on the Polish-Belarussian border has recovered after near extermination in the 1970s. Currently, it is intensively hunted in the Belarussian part of BPF and protected in the Polish part. We used a combination of molecular analysis, radiotracking, and field observation to study genetic diversity of the population after natural recolonisation and the consequences of heavy hunting for the genetic composition and social structure of wolf packs. Both microsatellite and mtDNA analyses revealed high genetic diversity. For 29 individuals and 20 microsatellite loci, the mean expected heterozygosity was 0.733. Four mtDNA haplotypes were found. Three of them had earlier been described from Europe. Their geographic distribution suggests that wolves recolonising BPF immigrated mainly from the north-east, and less effectively from the east and south-east. We traced the composition of 6 packs for a total of 26 pack-years. Packs were family units (a breeding pair with offspring) with occasional adoption of unrelated adult males, which occurred more frequently in packs living in the Belarussian part of the BPF, due to heavy hunting and poaching. Breeding pairs were half-sibs or unrelated wolves. Pair-bonds in the breeding pair lasted from 1 to 4 years and usually broke by the death of one or both mates. Successors of breeding females were their daughters, while a successor of a breeding male could be either his son or an alien wolf. As is evident from Bia?owie?a’s wolves, high genetic diversity may result from immigration of outside individuals, which are easily recruited to a heavily exploited local population.  相似文献   
42.
Adiponectin, secreted by fat tissue, is down - regulated in obesity and may be involved in obesity-related disorders. It has anti-inflammatory, antiatherosclerotic and antidiabetic effect. Obesity is a strong predictor for hypertension and cardiovascular diseases. Recent studies showed that adiponectin level has important role in metabolic disorders, arterial hypertension and ischemic heart disease but its effect on left ventricular hypertrophy (LVH) has not been fully clarified. The aim of this research is to determine whether the protective effect of adiponectin against development of left ventricular hypertrophy is decreased in hypertensive overweight patients. The study included 61 adult, overweight hypertensive patients, with body mass index in range 25-30 kg/m2. Patients had regular morning glucose serum values and regular creatinine level. They were divided into four groups, according to sex and the presence of LVH. There were 16 female and 15 male hypertensive patients with LVH and 15 female and 15 male hypertensive patients without LVH, who were a control group. Glucose profile, lipidogram, creatinine clearance and anthropometric measures were determined in all patients. Cardiovascular measurements were taken applying two-dimensional ultrasound. Adiponectin serum level was measured using enzyme immunoassay (ELISA). Results showed that adiponectin serum level was significantly lower in hypertensive, overweight females and males with LVH than in the control groups without LVH. Adiponectin serum level did not correlate significant with intraventricular or with posterior wall thickness of left ventricle. Hypoadiponectinemia presents part of neurohumoral, non-haemodynamic system who contributes to obesity-related hypertension and left ventricular hypertrophy development. Low adiponectin level together with others adipokines, cytokines and chemokines secreted by fat tissue could contribute to pathophysiologic changes of the myocardium via unknown molecular mechanisms yet.  相似文献   
43.
Type II restriction endonuclease activities of Helicobacter pylori strain Roberts and of the type strain H. pylori NCTC 11637 were detected and analysed by conventional techniques. The endonucleases were partially purified, their optima for activity and their recognition and cleavage sites were determined. H. pylori (Roberts) contained at least two enzymes: HpyBI was an isoschizomer of RsaI (GT/AC) and HpyBII was of a novel specificity (GTN/NAC). H. pylori NCTC 11637 was found to contain an isoschizomer of EcoRV (HpyCI: GAT/ATC) and at least one other enzyme which was too unstable to characterise.  相似文献   
44.
Interactive Tree Of Life (iTOL) is a web-based tool for the display, manipulation and annotation of phylogenetic trees. Trees can be interactively pruned and re-rooted. Various types of data such as genome sizes or protein domain repertoires can be mapped onto the tree. Export to several bitmap and vector graphics formats is supported. AVAILABILITY: iTOL is available at http://itol.embl.de  相似文献   
45.
The corpus callosum connects two cerebral hemispheres as the most voluminous fiber system in the human brain. The developing callosal fibers originate from immature pyramidal neurons, grow through complex pathways and cross the midline using different substrates in transient fetal structures. We analyzed cellular structures in the human corpus callosum on postmortem brains from the age of 18 weeks post conception to adult, using glial fibrillary acidic protein, neuron-specific nuclear protein, and chondroitin sulphate immunocytochemistry. We found the presence of transient cellular structures, callosal septa, which divide major fiber bundles and ventrally merge with subcallosal zone forming grooves for callosal axons. The callosal septa are composed of glial fibrillary acidic protein reactive meshwork, neurones and the chondroitin sulphate immunoreactive extracellular matrix. The developmental window of prominence of the callosal septa is between 18-34 weeks post conception which corresponds to the period of most intensive growth of callosal axons in human. During the early postnatal period the callosal septa become thinner and shorter, lose their neuronal and chondroitin sulphate content. In conclusion, transient expression of neuronal, glial and extracellular, growing substrate in the callosal septa, as septa itself, indicates their role in guidance during intensive growth of callosal fibers in the human brain. These findings shed some light on the complex morphogenetic events during the growth of the corpus callosum and represent normative parameters necessary for studies of structural plasticity after perinatal lesions.  相似文献   
46.
Complete sequences of the ribosomal internal transcribed spacers (ITS1 and ITS2) and karyological characters of the monozoic (unsegmented) tapeworm Atractolytocestus huronensis Anthony, 1958 (Cestoda: Caryophyllidea) from Slovakia were analysed, revealing considerable intra-genomic variability and triploidy in all analysed specimens. Analysis of 20 sequences of each ITS1 and ITS2 spacer yielded eight and 10 different sequence types, respectively. In individual tapeworms, two to four ITS1 and three to four ITS2 sequence types were found. Divergent intra-genomic ITS copies were mostly induced by nucleotide substitutions and different numbers of short repetitive motifs within the sequence. In addition, triploidy was found to be a common feature of A. huronensis. The karyotype of Slovakian A. huronensis possesses three sets of chromosomes (3= 24, = 4m + 3st + 1 minute chromosome), similar to the previously described triploidy in conspecific tapeworms from North America. Fluorescent in situ hybridisation (FISH) with a ssrDNA probe revealed two distinct rDNA clusters for each homologue of the triplet number 2. To date, A. huronensis is the only cestode species in which intra-individual ITS sequence variants were found in parallel with its triploid nature and multiple rDNA loci. Some of these molecular and genetic features were observed in several other species of basal or nearly basal tapeworms of the orders Caryophyllidea and Diphyllobothriidea, which indicates that the phenomena may be characteristic for evolutionarily lower tapeworms and deserve more attention in future studies.  相似文献   
47.
Conventional roentgenograms constitute the groundwork for the evaluation of diffuse interstitial lung disease (DILD). ILO classification with its symbols (additionally extended to granulomatoses) does not comprise pathoanatomic assumptions and does not enter lesion genesis for it could lead to diagnostic misconception. "High resolution" computer tomography (HRCT) provides the evaluation of lesion morphology and disease activity. After having treated our 129 patients with diffuse interstitial lung disease we have come to the conclusion that, beside pneumoconiosis, the application of extended standard ILO symbols are suitable to other interstitial pathology for the homogeneity of morphologic characteristics. As for diagnoses making, in distinction to other methods, it can be said that analyzing roentgenograms of the extended ILO provides high level of lesion evaluation standardization for diffuse interstitial disease as well as substantial congruity with CT finding. It is clear that such analysis cannot be applied in our daily work, however we have both concluded and proved that on conventional roentgenograms the condition of interstitial lesion can roughly be assessed. This is of high importance considering minimal dose of radiation exposure by standard tests in comparison with other radiological techniques. Nevertheless, CT scanning should be performed if there should be the need for the assessment of the morphology and the activity of lesion, to the benefit of our patients.  相似文献   
48.
The aim of this study was to examine the prevalence of dysmenorrhea in female adolescents and the influence of anthropological characteristics and lifestyle factors on menstrual pain. Two hundred and ninety seven girls from several elementary and secondary schools were interviewed about the presence of the menstrual pain, their age, height and weight, menarcheal age, menstrual cycles quality, smoking and sexual activity. There were 164 (55%) subjects with and one hundred and thirty three (45%) without dysmenorrhea. The adolescents with dysmenorrhea answered the questions about missing activities and taking pills for pain. No difference was observed between the girls with and the girls without dysmenorrhea in their chronological age, height, weight, menarcheal age, menstrual cycles quality, cigarette smoking and sexual activity. In the group of dysmenorrheic adolescents there was infrequent missing activities and bedrest, but missing school was observed in 22 percent and taking pills for pain was observed in 96 percent of the subjects. Young girls who experienced menstrual pain are good candidates for a prophylactic therapy, such as hormonal contraception. A replication of this study is needed for public health services in the future to improve the quality of life of the dysmenorrheic young women.  相似文献   
49.
The Aurora B kinase complex is a critical regulator of chromosome segregation and cytokinesis. In Caenorhabditis elegans, AIR-2 (Aurora B) function requires ICP-1 (Incenp) and BIR-1 (Survivin). In various systems, Aurora B binds to orthologues of these proteins. Through genetic analysis, we have identified a new subunit of the Aurora B kinase complex, CSC-1. C. elegans embryos depleted of CSC-1, AIR-2, ICP-1, or BIR-1 have identical phenotypes. CSC-1, BIR-1, and ICP-1 are interdependent for their localization, and all are required for AIR-2 localization. In vitro, CSC-1 binds directly to BIR-1. The CSC-1/BIR-1 complex, but not the individual subunits, associates with ICP-1. CSC-1 associates with ICP-1, BIR-1, and AIR-2 in vivo. ICP-1 dramatically stimulates AIR-2 kinase activity. This activity is not stimulated by CSC-1/BIR-1, suggesting that these two subunits function as targeting subunits for AIR-2 kinase.  相似文献   
50.
Toxic epidermal necrolysis syndrome is an uncommon, acute, life-threatening, medication-induced disorder with a reported mortality rate of 20 to 60 percent. Different variables have been identified as risk factors. The extent to which these variables, when combined, affect the mortality and outcome in toxic epidermal necrolysis syndrome patients has not yet been reliably defined. Because of the high mortality rate, the logistic analysis of studied variables was performed to see whether a prognostic algorithm could be developed to aid the management of these patients. Thus, a retrospective review of 56 consecutive toxic epidermal necrolysis syndrome patients treated over a period of 13 years was undertaken in the authors' burn center. The demographics included age, sex, race, and total body surface area involved. The other variables studied were comorbidities, sepsis, steroid administration, and the interval between onset of rash and burn center admission. Data were subjected to Fisher's exact test and logistic analysis. Thirty-six patients (64.3 percent) were alive and 20 (35.7 percent) died. Univariate analysis indicated that the male/female ratio was 12:24 for survivors and 9:11 for nonsurvivors (p = 0.4). The white/nonwhite ratio was 80 percent for survivors and 54 percent for nonsurvivors (p = 0.58). The median age was 48.4 +/- 22.8 years (survivors, 41.7 +/- 22.0; nonsurvivors, 60.5 +/- 19.5; p = 0.002). Total body surface area involvement for survivors was 56.9 +/- 32 and 77.7 +/- 21 for nonsurvivors (p = 0.005). The presence of one or more comorbidities between the two groups differed (53 percent survivors and 90 percent nonsurvivors, p = 0.007), indicating eight times higher odds of dying in their presence. The average time between the onset of symptoms and admission to the burn unit was 5.25 +/- 3.4 days for survivors and 7.15 +/- 4.5 days for nonsurvivors (p = 0.08). The presence of sepsis (19.4 percent survivors, 95 percent nonsurvivors, p < 0.001) decreased odds for survival by a factor of 79. Steroids given as a single dose or multiple doses before the patient's transfer to the burn unit were not significantly associated with death (44 percent survivors, 65 percent nonsurvivors, p = 0.14). A multivariate logistic regression model yielded odds ratios of 1.11 (95 percent confidence interval, 1.03 to 1.19) for age in years, 304 (95 percent confidence interval, 8.83 to 10,400) for the presence of sepsis, and 1.03 (95 percent confidence interval, 0.99 to 1.08) for body surface area in percent. All those entering the burn unit with sepsis died. Equivalently, no survivors had sepsis before admission to the burn unit, whereas 55 percent of nonsurvivors had sepsis before admission and 40 percent developed sepsis after admission. When investigating the effect of age and sepsis, no patients over age 60 ever having sepsis survived, whereas all those who were under 60 and without sepsis survived. Likewise, all patients whose age was over 60 and whose total body surface area involved was over 60 percent died. The main factors contributing to the mortality from toxic epidermal necrolysis syndrome, when considering covariates separately, are the presence of sepsis at any time (odds ratio, 79), the presence of comorbidities (odds ratio, 8.05), age, and total body surface area, whereas multivariate models suggested age (odds ratio per year of additional age, 1.11), total body surface area (odds ratio per additional percent of body surface area, 1.03), and the presence of sepsis (odds ratio, 304). By using the actual coefficients in the logistic model, the log odds that the patient will die as the result of his or her condition can be summarized in the following formula: -11.5 + (10 percent of the patient's age + 3 percent of total body surface area + 5.75 if sepsis is present). The awareness of the importance of these covariates, and their early recognition as risk factors, should offer a focused approach to the patients' management and improve their outcome.  相似文献   
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