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991.
Abstract: The complete neurocranium plus palatoquadrate of the plagiosaurid temnospondyl Gerrothorax pulcherrimus from the Middle Triassic of Germany is described for the first time, based on outer morphological observations and micro‐CT scanning. The exoccipitals are strong elements with paroccipital processes and well‐separated occipital condyles. Anterolaterally, the exoccipitals contact the otics, which are mediolaterally elongated and have massive lateral walls. The otics contact the basisphenoid, which shows well‐developed sellar processes. Anteriorly, the basisphenoid is continuous with the sphenethmoid region. In its posterior portion, the sphenethmoid gives rise to robust, laterally directed laterosphenoid walls, a unique morphology among basal tetrapods. The palatoquadrate is extensively ossified. The quadrate portion overlaps the descending lamina of squamosal and ascending lamina of pterygoid anteriorly, almost contacting the epipterygoid laterally. The epipterygoid is a complex element and may be co‐ossified with otics and laterosphenoid walls. It has a broad, sheet‐like footplate and a horizontally aligned ascending process that contacts the laterosphenoid walls. The degree of ossification of the epipterygoid, however, is subject to individual variation obviously independent from ontogenetic changes. The stapes of Gerrothorax is a large, blade‐like element that differs conspicuously from the plesiomorphic temnospondyl condition. It has a prominent anterolateral projection which has not been observed in other basal tetrapods. Morphology of neurocranium and palatoquadratum of Gerrothorax most closely resembles that of the Russian plagiosaurid Plagiosternum danilovi, although the elements are less ossified in the latter. The extensive endocranial ossification of Gerrothorax is consistent with the general high degree of ossification in the exo‐ and endoskeleton of this temnospondyl and supports the view that a strong endocranial ossification cannot be evaluated as a plesiomorphic character in basal tetrapods. 相似文献
992.
Background
Salmonella enterica serovar Hadar (S. Hadar) is a highly prevalent foodborne pathogen and therefore a major cause of human gastroenteritis worldwide. Outer membrane proteins whose production is often regulated by environmental conditions also play important roles in the adaptability of bacterial pathogens to various environments. 相似文献993.
It was found that water preliminary activated with vector potential changes mobility of infusoria, bringing into it, the rate of sugar fermentation in yeast cells and a drinking attractivity of water for mice. It was also shown that water physical parameters changed after water activation: UV absorptions spectrum and a state of a silica admixture. It was supposed that water is the initial target when weak electromagnetic fields have an influence on biological objects. 相似文献
994.
JÉRÔME ATEUDJIEU JOHN WILLIAMS MARIE HIRTLE CÉDRIC BAUME JOYCE IKINGURA ALASSANE NIARÉ DOMINIQUE SPRUMONT 《Developing world bioethics》2010,10(2):88-98
Background: As actors with the key responsibility for the protection of human research participants, Research Ethics Committees (RECs) need to be competent and well‐resourced in order to fulfil their roles. Despite recent programs designed to strengthen RECs in Africa, much more needs to be accomplished before these committees can function optimally. Objective: To assess training needs for biomedical research ethics evaluation among targeted countries. Methods: Members of RECs operating in three targeted African countries were surveyed between August and November 2007. Before implementing the survey, ethical approvals were obtained from RECs in Switzerland, Cameroon, Mali and Tanzania. Data were collected using a semi‐structured questionnaire in English and in French. Results: A total of 74 respondents participated in the study. The participation rate was 68%. Seventy one percent of respondents reported having received some training in research ethics evaluation. This training was given by national institutions (31%) and international institutions (69%). Researchers and REC members were ranked as the top target audiences to be trained. Of 32 topics, the top five training priorities were: basic ethical principles, coverage of applicable laws and regulations, how to conduct ethics review, evaluating informed consent processes and the role of the REC. Conclusion: Although the majority of REC members in the targeted African countries had received training in ethics, they expressed a need for additional training. The results of this survey have been used to design a training program in research ethics evaluation that meets this need. 相似文献
995.
Drumming display sites of male Ruffed Grouse Bonasa umbellus serve as activity centres and occur in a variety of forest types and age classes. We used a case‐control study design and model selection to evaluate a set of predictions about habitat constraints placed upon Grouse given the habitat where their breeding season activity centres were located. We located 110 individual Grouse activity centres near Cloquet, Minnesota, between 2002 and 2005, and 40 activity centres at two other sites in northern Minnesota in 2005. Our most parsimonious model indicated that Ruffed Grouse used logs more than other potential drumming structures (e.g. stumps, dirt mounds or roots) and sites with a higher density of shrubs as compared with unused sites. Predicted values from this model correlated with observed values from independently sampled areas. Structures used by Grouse for their drumming display were characterized by a greater density of aspen stems than unused sites when in young aspen and mature pine, but not when in other forest types. The patterns of habitat selection that we observed supported predictions (1) that the differences in habitats at larger spatial scales (e.g. forest stands or breeding territories) may impose certain constraints on specific sites selected for their drumming display, and (2) that some of these constraints may vary by forest type. 相似文献
996.
997.
998.
Eszter Tuboly Mitsuru Futakuchi Gabriella Varga Daniel Érces Tünde Tőkés Andras Mészáros József Kaszaki Masumi Suzui Masaki Imai Alan Okada Noriko Okada Mihály Boros Hidechika Okada 《Microbiology and immunology》2016,60(1):35-46
Acute mesenteric ischemia (AMI) is caused by considerable intestinal injury, which is associated with intestinal ischemia followed by reperfusion. To elucidate the mechanisms of ischemia/reperfusion injuries, a C5a inhibitory peptide termed AcPepA was used to examine the role of C5a anaphylatoxin, induction of inflammatory cells, and cell proliferation of the intestinal epithelial cells in an experimental AMI model. In this rat model, the superior mesenteric artery was occluded and subsequently reperfused (Induce‐I/R). Other groups were treated with AcPepA before ischemia or reperfusion. Induce‐I/R induced injuries in the intestine and AcPepA significantly decreased the proportion of severely injured villi. Induce‐I/R induced secondary receptor for C5a‐positive polymorphonuclear leukocytes in the vessels and CD204‐positive macrophages near the injured site; this was correlated with hypoxia‐induced factor 1‐alpha‐positive cells. Induction of these inflammatory cells was attenuated by AcPepA. In addition, AcPepA increased proliferation of epithelial cells in the villi, possibly preventing further damage. Therefore, Induce‐I/R activates C5a followed by the accumulation of polymorphonuclear leukocyte and hypoxia‐induced factor 1‐alpha‐producing macrophages, leading to villus injury. AcPepA, a C5a inhibitory peptide, blocks the deleterious effects of C5a, indicating it has a therapeutic effect on the inflammatory consequences of experimental AMI. 相似文献
999.
Éric Villiard Henner Brinkmann Olga Moiseeva Frédérick A Mallette Gerardo Ferbeyre Stéphane Roy 《BMC evolutionary biology》2007,7(1):180
Background
Urodele amphibians like the axolotl are unique among vertebrates in their ability to regenerate and their resistance to develop cancers. It is unknown whether these traits are linked at the molecular level. 相似文献1000.
RONALD C KESSLER MATTHIAS ANGERMEYER JAMES C ANTHONY RON DE GRAAF KOEN DEMYTTENAERE ISABELLE GASQUET GIOVANNI DE GIROLAMO SEMYON GLUZMAN OYE GUREJE JOSEP MARIA HARO NORITO KAWAKAMI AIMEE KARAM DAPHNA LEVINSON MARIA ELENA MEDINA MORA MARK A OAKLEY BROWNE JOSé POSADA-VILLA DAN J STEIN CHEUK HIM ADLEY TSANG SERGIO AGUILAR-GAXIOLA JORDI ALONSO SING LEE STEVEN HEERINGA BETH-ELLEN PENNELL PATRICIA BERGLUND MICHAEL J GRUBER MARIA PETUKHOVA SOMNATH CHATTERJI T. BEDIRHAN üSTüN 《World psychiatry》2007,6(3):168-176
Data are presented on the lifetime prevalence, projected lifetime risk,
and age-of-onset distributions of mental disorders in the World Health Organization
(WHO)''s World Mental Health (WMH) Surveys. Face-to-face community surveys
were conducted in seventeen countries in Africa, Asia, the Americas, Europe,
and the Middle East. The combined numbers of respondents were 85,052. Lifetime
prevalence, projected lifetime risk, and age of onset of DSM-IV disorders
were assessed with the WHO Composite International Diagnostic Interview (CIDI),
a fully-structured lay administered diagnostic interview. Survival analysis
was used to estimate lifetime risk. Median and inter-quartile range (IQR)
of age of onset is very early for some anxiety disorders (7-14, IQR: 8-11)
and impulse control disorders (7-15, IQR: 11-12). The age-of-onset distribution
is later for mood disorders (29-43, IQR: 35-40), other anxiety disorders (24-50,
IQR: 31-41), and substance use disorders (18-29, IQR: 21-26). Median and IQR
lifetime prevalence estimates are: anxiety disorders 4.8-31.0% (IQR: 9.9-16.7%),
mood disorders 3.3-21.4% (IQR: 9.8-15.8%), impulse control disorders 0.3-25.0%
(IQR: 3.1-5.7%), substance use disorders 1.3-15.0% (IQR: 4.8-9.6%), and any
disorder 12.0-47.4% (IQR: 18.1-36.1%). Projected lifetime risk is proportionally
between 17% and 69% higher than estimated lifetime prevalence (IQR: 28-44%),
with the highest ratios in countries exposed to sectarian violence (Israel,
Nigeria, and South Africa), and a general tendency for projected risk to be
highest in recent cohorts in all countries. These results document clearly
that mental disorders are commonly occurring. As many mental disorders begin
in childhood or adolescents, interventions aimed at early detection and treatment
might help reduce the persistence or severity of primary disorders and prevent
the subsequent onset of secondary disorders. 相似文献