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1.
In-situ studies on sublittoral soft bottom macrofauna (depth: 14–16 m) employing the underwater laboratory (UWL) “Helgoland” were carried out. Sets of samples were compared for small-scale local and short-term changes in species richness, faunal abundance, numerical dominance, diversity, evenness, homogeneity, and similarity. It could be shown that minor differences in sediment quality can cause conspicuous heterogeneity within a small sampling area (diameter: ca. 100 m). Both spatfall and mortality of benthic invertebrates can change the faunal structure within a short period (two months). The degree of change varies between species and thus at stations harbouring different faunal assemblages as well.  相似文献   
2.
In marine ecosystems, macroalgae are the habitat for several microorganisms, fungi being among them. In the Antarctic benthic coastal ecosystem, macroalgae play a key role in organic matter cycling. In this study, 13 different macroalgae from Potter Cove and surrounding areas were sampled and 48 fungal isolates were obtained from six species, four Rhodophyta Ballia callitricha, Gigartina skottsbergii, Neuroglossum delesseriae and Palmaria decipiens, and two Phaeophyceae: Adenocystis utricularis and Ascoseira mirabilis. Fungal isolates mostly belonged to the Ascomycota phylum (Antarctomyces, Cadophora, Cladosporium, Penicillium, Phialocephala, and Pseudogymnoascus) and only one to the phylum Mucoromycota. Two of the isolates could not be identified to genus level, implying that Antarctica is a source of probable novel fungal taxa with enormous bioprospecting and biotechnological potential. 73% of the fungal isolates were moderate eurypsychrophilic (they grew at 5–25 °C), 12.5% were eurypsychrophilic and grew in the whole range, 12.5% of the isolates were narrow eurypsychrophilic (growth at 15–25 °C), and Mucoromycota AUe4 was classified as stenopsychrophilic as it grew at 5–15 °C. Organic extracts of seven macroalgae from which no fungal growth was obtained (three red algae Georgiella confluens, Gymnogongrus turquetii, Plocamium cartlagineum, and four brown algae Desmarestia anceps, D. Antarctica, Desmarestia menziesii, Himantothallus grandifolius) were tested against representative fungi of the genera isolated in this work. All extracts presented fungal inhibition, those from Plocamium cartilagineum and G. turquetii showed the best results, and for most of these macroalgae, this represents the first report of antifungal activity and constitute a promising source of compounds for future evaluation.  相似文献   
3.
A model is described which provides a simple algorithm to compute the reaction times of saccadic eye movements and reach movements aimed at a single visual target. It is assumed, that the two movements are prepared inparallel and initiated independently unless the preparation of the saccade for some reason takes longer than the preparation of the reach movement. In the latter case the final command to execute the reach movement is synchronized with that to execute the eye movement and therefore the corresponding reaction times are highly correlated in a one-to-one relationship. Random variables are used to predict sets of data that are directly comparable with the experimental results. The algorithm includes the effects of daily practice (learning). The structure of the model and its computational results will be compared with the physiological data from monkey and man.  相似文献   
4.
Depression after liver transplantation has been associated with decreased survival, but the effects of pre-transplant depression on early and late post-transplant outcomes remain incompletely evaluated. We assessed all patients who had undergone single-organ liver transplantation at a single center over the prior 10 years. A diagnosis of pre-transplant depression, covariates, and the outcomes of interest were extracted from the electronic medical record. Potential covariates included demographics, etiology and severity of liver disease, comorbidities, donor age, graft type, immunosuppression, and ischemic times. In multivariable models adjusting for these factors, we evaluated the effect of pre-transplant depression on transplant length of stay (LOS), discharge disposition (home vs. facility) and long-term survival. Among 1115 transplant recipients with a median follow-up time of 5 years, the average age was 56±11 and MELD was 12±9. Nineteen percent of the study population had a history of pre-transplant depression. Pre-transplant depression was associated with longer LOS (median = 19 vs. 14 days, IRR = 1.25, CI = 1.13,1.39), discharge to a facility (36% vs. 25%, OR 1.70,CI = 1.18,2.45), and decreased survival (HR = 1.54,CI = 1.14,2.08) in this cohort, accounting for other potential confounders. In conclusion, pre-transplant depression was significantly associated with longer transplant length of stay, discharge to a facility, and mortality in this cohort.  相似文献   
5.
Nucleotide sequence comparisons were used to investigate the evolution of P transposable elements and the possibility that horizontal transfer has played a role in their occurrence in natural populations of Drosophila and other Diptera. The phylogeny of P elements was examined using published sequences from eight dipteran taxa and a new, partial sequence from Scaptomyza elmoi. The results from a number of different analyses are highly consistent and reveal a P-element phylogeny that contradicts the phylogeny of the species. At least three instances of horizontal transfer are necessary to explain this incongruence, but other explanations cannot be ruled out at this time.   相似文献   
6.
Salmonella genomic island 1 (SGI1) contains a multidrug resistance region conferring the ampicillin-chloramphenicol-streptomycin-sulfamethoxazole-tetracycline resistance phenotype encoded by bla(PSE-1), floR, aadA2, sul1, and tet(G). Its increasing spread via interbacterial transfer and the emergence of new variants are important public health concerns. We investigated the molecular properties of SGI1-carrying Salmonella enterica serovars selected from a European strain collection. A total of 38 strains belonging to S. enterica serovar Agona, S. enterica serovar Albany, S. enterica serovar Derby, S. enterica serovar Kentucky, S. enterica serovar Newport, S. enterica serovar Paratyphi B dT+, and S. enterica serovar Typhimurium, isolated between 2002 and 2006 in eight European countries from humans, animals, and food, were subjected to antimicrobial susceptibility testing, molecular typing methods (XbaI pulsed-field gel electrophoresis [PFGE], plasmid analysis, and multilocus variable-number tandem-repeat analysis [MLVA]), as well as detection of resistance and virulence determinants (PCR/sequencing and DNA microarray analysis). Typing experiments revealed wide heterogeneity inside the strain collection and even within serovars. PFGE analysis distinguished a total of 26 different patterns. In contrast, the characterization of the phenotypic and genotypic antimicrobial resistance revealed serovar-specific features. Apart from the classical SGI1 organization found in 61% of the strains, seven different variants were identified with antimicrobial resistance properties associated with SGI1-A (S. Derby), SGI1-C (S. Derby), SGI1-F (S. Albany), SGI1-L (S. Newport), SGI1-K (S. Kentucky), SGI1-M (S. Typhimurium), and, eventually, a novel variant similar to SGI1-C with additional gentamicin resistance encoded by aadB. Only minor serovar-specific differences among virulence patterns were detected. In conclusion, the SGI1 carriers exhibited pathogenetic backgrounds comparable to the ones published for susceptible isolates. However, because of their multidrug resistance, they may be more relevant in clinical settings.  相似文献   
7.
While John Wesley''s Primitive Physick (1747) cannot be termed a classic of British medical literature, it must certainly be identified as one of the most popular volumes published in England during the eighteenth century. Although the work came under attack from contemporary surgeons, physicians, and apothecaries, who maintained that its remedies were founded upon ignorance, Wesley probably knew as much as most members of the medical profession; in fact, on no less than twenty instances throughout the volume, he paraphrases or cites directly from prominent physicians and theorists—such figures as Sydenham, Boerhaave, Cheyne, Mead, and Huxham. However, despite its obvious emphasis upon practical remedies, the underlying focus of Primitive Physick is upon the soul of man. Wesley had consulted some sources, common sense, and his own experience, tempering those with the general principle of “doing good to all men,” particularly “those who desire to live according to the gospel....” Thus, the Methodist patriarch''s own formula for life had as much to do with the spread of Primitive Physick throughout eighteenth-century Britain and America as did all of the remedies and suggestions imprinted upon its pages.  相似文献   
8.
Reaction time measurements were used to test the possibility that an eye and a reach movement both aimed at the same visual target share a common final motor command. This hypothesis predicts highly correlated pairs of reaction times on a trial by trial basis. The experiments were based on the earlier observation that long saccadic reaction times (above 200 ms) with a large scatter (150–300 ms) are obtained if the central fixation point remained visible through out a trial (overlap paradigm), whereas extremely short saccadic reaction times (around 120 ms) with a small scatter (100–150 ms) occur if the fixation point was turned off some time (200 ms) before the target appeared (gap paradigm). In the overlap paradigm high correlations (coefficients up to 0.95) between saccadic and reach reaction times were obtained and the corresponding linear regression lines had a slope of almost one. In the gap paradigm, however, correlations were almost absent even though the mean reach reaction times were considerably decreased. These observations clearly contradict the common command hypothesis, but can be explained by the assumption that the execution of the reach movement depends on the completion of the preparation of the saccade but not vice versa (one way synchronization hypothesis).  相似文献   
9.
10.

Objective

To examine the associations between pet keeping in early childhood and asthma and allergies in children aged 6–10 years.

Design

Pooled analysis of individual participant data of 11 prospective European birth cohorts that recruited a total of over 22,000 children in the 1990s.

Exposure definition

Ownership of only cats, dogs, birds, rodents, or cats/dogs combined during the first 2 years of life.

Outcome definition

Current asthma (primary outcome), allergic asthma, allergic rhinitis and allergic sensitization during 6–10 years of age.

Data synthesis

Three-step approach: (i) Common definition of outcome and exposure variables across cohorts; (ii) calculation of adjusted effect estimates for each cohort; (iii) pooling of effect estimates by using random effects meta-analysis models.

Results

We found no association between furry and feathered pet keeping early in life and asthma in school age. For example, the odds ratio for asthma comparing cat ownership with “no pets” (10 studies, 11489 participants) was 1.00 (95% confidence interval 0.78 to 1.28) (I2 = 9%; p = 0.36). The odds ratio for asthma comparing dog ownership with “no pets” (9 studies, 11433 participants) was 0.77 (0.58 to 1.03) (I2 = 0%, p = 0.89). Owning both cat(s) and dog(s) compared to “no pets” resulted in an odds ratio of 1.04 (0.59 to 1.84) (I2 = 33%, p = 0.18). Similarly, for allergic asthma and for allergic rhinitis we did not find associations regarding any type of pet ownership early in life. However, we found some evidence for an association between ownership of furry pets during the first 2 years of life and reduced likelihood of becoming sensitized to aero-allergens.

Conclusions

Pet ownership in early life did not appear to either increase or reduce the risk of asthma or allergic rhinitis symptoms in children aged 6–10. Advice from health care practitioners to avoid or to specifically acquire pets for primary prevention of asthma or allergic rhinitis in children should not be given.  相似文献   
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