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1.
Seasonal variation in the occurrence of cardiovascular and cerebrovascular events, including pulmonary embolism (PE), has been reported; however, recent large‐scale, population‐based studies conducted in the United States did not confirm such seasonality. The aim of this large‐scale population study was to determine whether a temporal pattern in the occurrence of PE exists. The analysis considered all consecutive cases of PE in the database of all hospital admissions of the Emilia Romagna region in Italy at the Center for Health Statistics between January 1998 and December 2005. PE cases were first grouped according to season of occurrence, and the data were analyzed by the χ2 test for goodness of fit. Then, inferential chronobiologic (cosinor and partial Fourier) analysis was applied to monthly data, and the best‐fitting curve for the annual variation was derived. The total sample consisted of 19,245 patients (8,143 male, mean age 71.6±14.1 yrs; 11,102 female, mean age 76.1±13.7 yrs). Of these, 2,484 were <65 yrs, 5,443 were between 65 and 74, and 11,318 were ≥75 yrs. There were 4,486 (23.3%) fatal‐case outcomes. PE occurred least frequently in spring (n=4,442 or 23.1%) and most frequent in winter (n=5,236 or 27.2%, goodness of fit χ2=75.75, p<0.001). Similar results were obtained for subgroups formed by gender, age, fatal/non‐fatal outcome, presence/absence of major underlying co‐morbid conditions, and specific risk factors. Inferential chronobiological analysis identified a significant annual pattern in PE, with the peak between November and December for the total sample of cases (p<0.001), males (p<0.001), females (p=0.002), fatal and non‐fatal cases (p<0.001 for both), and subgroups formed by age (<65 yrs, p=0.012; 65–74 yrs, p<0.001; ≥75 yrs, p=0.012). This pattern was independent of the presence/absence of hypertension (p=0.003 and p<0.001, respectively), pulmonary disease (p<0.001 and p<0.001, respectively), stroke (p<0.001 and p=0.004, respectively), neoplasms (p=0.005 and p=0.001, respectively), heart failure (p=0.022 and p<0.001, respectively), and deep vein thrombosis (p=0.002 and p<0.001, respectively). However, only a non‐statistically significant trend was found for subgroups formed by cases of diabetes mellitus, infections, renal failure, and trauma.  相似文献   

2.
<正>Filamentous fungi are one of the major sources of natural products (NPs; which are also termed as secondary metabolites (SMs)) with diverse biological activities, which have been widely used in agriculture, industry, and pharmaceuticals. Fungi are the second largest species in nature, and their biodiversity implies genomic diversity, which, in turn,predicts the structural diversity of metabolites. In general,  相似文献   

3.
Dynamics of the evapotranspirational demands in the Czech Republic within three decades from 1961 to 1990 has been studied. The determination of the levels of influence of the respective natural components depends on the regionalized modelling techniques. The project of regionalized modelling is theoretically based on the potential evapotranspiration values (ET 0) calculated by FAO methodology (eqs. 1, 2) and the series of temperature and rainfall observations obtained by climatologic stations during a 30-year period from 1961 to 1990 and its relation to the absolute altimetric. The DMR-2 military digital elevation model of the Czech Republic relief consisting of a regular network of points with their altitudes specified in meters was used for the purpose of regionalized modelling. One step of the network in the S-42 coordinate system with the Gauss conforms cylindrical projection is equal to 100 meters; this implies that the smallest area for which the data can be processed is 1 hectare. The digital relief model can be linked to both direct (temperature, precipitation) and derived (evapotranspiration) quantities, which is one of the many novelties of regionalized modelling. The climatic data used in regionalized modelling records daily measurements were obtained by 85 climatologic and rainfall-monitoring stations from 1961 to 1990. Our results showed an appreciable decrease of the most drying area (ratio P/ET0 up to 0.755) in the last decade 1981–90; half as less amounts compared with the previous decade 1971–80 (about 500,000 hectares). On the other hand, an apparent increase (more than 500,000 hectares in comparison with the previous decade 1971–80) of the wettest area (ratio P/ET0 over 1.508) through the last decade was observed. Both first decades 1961–70 and 1971–80 look similar. The project mentioned in this article has made it possible to create models for the different time intervals which have showed higher reliability for heterogeneous application.  相似文献   

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The effects of 0.09 saturated solutions of the n-alkanols n-hexanol to n-tridecanol on the surface (compensation) potential of lipid monolayers have been examined. Actions on monolayers spread from pure egg phosphatidylcholine have been compared with effects on a system containing a 2:1 mole ratio of egg phosphatidylcholine and cholesterol. The mean compensation potential for the pure phospholipid system was 475 ± 9 mV; addition of cholesterol increased the potential to 503 ± 10 mV. All n-alkanols tested reduced the surface potential in both systems. The reduction was larger in the pure phospholipid system but the difference in effect between lipid systems declined as the n-alkanol chainlength increased, becoming negligible by n-tridecanol. These results are considered in relation to the ‘cut-off’ in biological activity of n-alkanols around n-tridecanol.  相似文献   

6.
Cultural and environmental factors interact in determining the genetic structure of human populations. Bio-demographic investigations of ethnic minorities are able to disentangle the influences that these two components have on the evolution of the genetic structure of a population. The ethnic minority of the Arb?reshe of the province of Cosenza (Calabria, southern Italy) is analyzed in this paper and its bio-demographic structure in the early 1800s is compared with that of neighboring Italian populations. The data derive from surnames recorded in the birth registers of the 19 Arbdreshe municipalities of the province of Cosenza and in 5 non-Arb?reshe municipalities of the same province. Isonymy and repeated pairs of surnames are used to analyze the bio-demographic structure of these populations, while analysis of isonymic relationships is used to investigate the variability between populations. Higher values of marital isonymy and subdivision into subpopulations characterize the Arb?reshe populations with respect to their non-Arb?reshe neighbors. However, the high range of variability of these parameters suggests a strong influence of geographic location on the marriage pattern of each community. At the same time, cultural differences linked to group identity had a strong impact in limiting marriage exchanges between the different ethnic groups living in the province of Cosenza in the early 1800s. In fact, the analysis of isonymic relationships demonstrates that geographic location shaped kinship patterns among the Arbereshe communities, but it also shows that the non-Arb?reshe neighbors formed a clearly separate reproductive cluster.  相似文献   

7.
Summary SummaryYeast cultures progressing from the exponential to the stationary phase of growth showed changes in cell sensitivity to physical agents such as UV light, heat shock at 52° C and the chemical mutagens ethyl methane sulphonate, nitrous acid and mitomycin C.Exponential phase cells showed maximum resistance to UV light and minimum resistance to heat shock and the three chemicals. The increased resistance of exponential phase cells to UV light was shown to be dependent upon the functional integrity of the RAD 50 gene.Treatment of growing yeast cultures with radioactively labelled ethyl methane sulphonate indicated the preferential uptake of radioactivity during the sensitive exponential stage of growth. The results indicated that the differential uptake of the chemical mutagens was responsible for at least a fraction of the variations in cell sensitivity observed in yeast cultures at different phases of growth.  相似文献   

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10.
Fungal endophyte (FE) communities can be shaped by environmental conditions and/or host-plant affinities. Hawaiʻi's landscape-dominant woody genus Metrosideros (Myrtaceae) comprises several vegetatively distinct taxa that are non-randomly distributed across environments, and their FE communities are poorly known. We examined the relative importance of Metrosideros taxon and environment (elevation) on FE communities on Oʻahu. ITS1 rDNA barcoding and sequencing of 113 trees detected a richness of 1,637 FEs representing 5 phyla, 223 genera, and 200 species. Variation in FE diversity was significantly explained by host taxon and site with considerable overlap in FE communities among taxa. FE communities did not vary between pubescent and glabrous taxa or across elevations, possibly due to the relatively narrow range of environmental conditions represented on Oʻahu relative to taller islands. A significant pattern of isolation by distance in FE composition was detected both among and within sites, consistent with restricted dispersal of FEs across the island.  相似文献   

11.
A metagenomic (community genomic) library consisting of 5,760 bacterial artificial chromosome clones was prepared in Escherichia coli DH10B from DNA extracted from the large-bowel microbiota of BALB/c mice. DNA inserts detected in 61 randomly chosen clones averaged 55 kbp (range, 8 to 150 kbp) in size. A functional screen of the library for β-glucanase activity was conducted using lichenin agar plates and Congo red solution. Three clones with β-glucanase activity were detected. The inserts of these three clones were sequenced and annotated. Open reading frames (ORF) that encoded putative proteins with identity to glucanolytic enzymes (lichenases and laminarinases) were detected by reference to databases. Other putative genes were detected, some of which might have a role in environmental sensing, nutrient acquisition, or coaggregation. The insert DNA from two clones probably originated from uncultivated bacteria because the ORF had low sequence identity with database entries, but the genes associated with the remaining clone resembled sequences reported in Bacteroides species.  相似文献   

12.
The two translocation chromosomes in the Poso 5B/7B translocation have been isolated in separate heterozygous aneuploid stocks (19II+5B+T). The translocation breakpoints are in the long arm of chromosome 7B and the short arm of chromosome 5B. The translocation chromosome bearing the 5BL pairing inhibitor was obtained as a homozygous aneuploid (19II+T 1 II ). The heterozygous aneuploid hemizygous for the pairing inhibitor (19II+5B+T2) was used to produce intergeneric hybrids. Only a small percentage were of the high-pairing type (17%), the majority having received chromosome 5B through the egg. This indicates a strong selection against eggs containing the translocation chromosome deficient for the pairing inhibitor.  相似文献   

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14.
The synthesis and inhibitory potencies of a novel series of β-amino alcohols, based on the hit-compound 3-[3′-(4″-cyclopent-2?-en-1?-ylphenoxy)-2′-hydroxypropyl]-5,5 dimethylimidazolidine-2,4-dione as specific inhibitors of mycobacterial N-acetyltransferase (NAT) enzymes are reported. Effects of synthesised compounds on growth of Mycobacterium tuberculosis have been determined.  相似文献   

15.
In this work, the studies on the previously detected phenomenon of concealed heterokaryosis in Saccharomyces cerevisiaewere continued. In genetic and Southern blotting experiments, one of the nuclei in the heterokaryon was shown to be active (capable of division and ensuring the corresponding cell phenotype), whereas the other was not expressed until the heterokaryotic clone was transferred to the medium selective for this concealed nucleus. Moreover, the concealed nucleus was able to assume the active state after fusion with the second parental nucleus. It was analyzed whether the nuclei with new marker combinations occurring in meiosis can behave as exceptional nuclei. Tetrad analysis of hybrids carrying the kar1mutation in their nuclei revealed the relatively high percentage of exceptional tetrads (more than 10%). One spore in these tetrads usually formed diploid cells capable of sporulation. The presented data of genetic and molecular biological studies testify in favor of the assumption that abnormal spores contain two nuclei, which form an illegitimate hybrid after fusion. An extraneous nucleus (termed x) has usually a genotype close to that of one of the spores in this tetrad. Thus, it was assumed that the additional DNA replication round occurs in the absence of cell division during one of meiotic divisions. Results of cytological analysis conducted by the method of specific DNA staining confirmed the existence of exceptional tetrads, one spore of which contains two nuclei.  相似文献   

16.
These results support our hypothesis that class III compounds, with a positive inotropic effect, increase intercellular coupling and synchronization, mainly by preventing intracellular Ca overload. They act as defibrillating compound, similar to cAMP and adrenaline, most probably due to their so called sympathomimetic effect. In our opinion, their cardioprotective effects, resembling cardioversion, are not related to their ability to prolong APD and ERP. Moreover, we suggest that any compound that possesses these sympathomimetic effects, but without inducing the arrhythmogenic prolongation of APD, may exhibit a potent, safety and more efficient antiarrhythmic - defibrillating ability.  相似文献   

17.
Summary

The normal sequence of spermatogenesis in Fasciola hepatica has been established. The single-celled primary spermatogonium—after three mitotic divisons and one meiotic division, accompanied by incomplete cytokinesis—gives rise to a rosette of 32 spermatid cells from which the spermatozoa differentiate. Rosette formation begins to develop at the tertiary spermatogonial stage and leads to individual cells being joined together via a central “cytophore”. As revealed by transmission electron microscopy (TEM), spermatogenesis is readily disrupted by the active sulphoxide metabolite of triclabendazole (TCBZSX), a relatively new benzimidazole anthelmintic. Following short incubation times in this drug (3 h onwards), the spermatogonial stages become mitotically inactive and detached from their normal position close to the wall of the tubule. The rosette stages become increasingly disrupted, with fragmentation of the cytoplasmic cytophore. After longer time periods (12–24 h) the testis tubules were almost completely empty with few spermatogenic stages or mature spermatozoa present. The ultrastructural effects of TCBZ-SX bear some resemblance to those observed after treatment with tubulozole, a potent microtubule inhibitor. The results with the two drugs are discussed in relation to the mode of action of triclabendazole, which at present is unknown.  相似文献   

18.
Between 1985 and 1990 we observed 2085 cases of dermatophytoses in the Florence area of Italy.Trichophyton rubrum andMicrosporum canis were the major etiological agents. 126 cases of dermatophytoses observed during this period were caused byTrichophyton mentagrophytes. Most of the patients came from rural areas or they kept pets.Epidermophyton floccosum ranked fourth in frequency (95 cases). The patients were adults and mainly males, most of whom engaged in sports or lived in group environments.Microsporum gypseum was isolated in 31 cases. Infections occurred directly from contact with soil or domestic animals. We report the principal clinical data concerning these last three dermatophyte infections.  相似文献   

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20.
Niche areas of ships, such as lateral thruster tunnels, sea chests, and propellers, are often hot spots for the accumulation of biofouling organisms, a potential source of aquatic invasive species. Yet, the relative importance of different niche areas is poorly resolved, in terms of both total surface area and the associated biota (i.e., the species of organisms and their abundances). To address this information gap, a method was developed to estimate the extent of various niche areas in the global fleet of 120,252 commercial ships active between 1999 and 2013. The total niche area for these vessels was estimated to be 32,996 × 103 m2, representing approximately 10% of the total wetted surface area (WSA) available for colonization by biota. Considering the portion of niche areas relative to the total WSA, it was highest for passenger vessels (27%), followed by tugs (25%), and fishing vessels (21%), with niche areas representing a small portion of the WSA for bulk carriers and tankers (7–8%). Examining the different types of niche areas, thruster tunnels had the greatest total extent (10,189 × 103 m2), representing a disproportionately large contribution (>50%) of the total niche area for passenger vessels and tugs compared to other vessel types. This result, combined with the use and cleaning of thrusters, may render them “super-hot spots” of biofouling. The uneven distribution and extent of niche areas across vessels has implications for transfers of organisms and management strategies to reduce invasions associated with the surfaces of ships.  相似文献   

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