Publications by authors named "N Alexeeva"

Transcranial magnetic stimulation (TMS) has been used for many years to study the pathophysiology of amyotrophic lateral sclerosis (ALS). Based on single- or dual-pulse TMS and EMG and/or single motor unit (MU) recordings, many groups have described a loss of central inhibition as an early marker of ALS dysfunction, reflecting a state of cortical 'hyperexcitability'. This conclusion is not without its detractors, however, leading us to reexamine this issue using 4-pulse TMS, shown previously to be more effective for testing central motor pathway functional integrity.

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Article Synopsis
  • All major arthropod groups have excretory glands believed to be an ancestral trait, but the presence of these organs in pycnogonids (a type of ancient aquatic chelicerate) was uncertain, particularly due to limited anatomical research.
  • This study investigated four nymphonids using advanced microscopy techniques and found that all species possess distinct excretory organs, detailing their structure and various components.
  • Additionally, the research traced the development of these organs, revealing their anatomical location in the appendages, and suggests that the structure of the sacculus may have evolved secondarily, though its exact classification compared to other arthropods remains ambiguous.
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The family Callipallenidae Hilton, 1942 belongs to the superfamily Nymphonoidea Pocock, 1904 together with other family, Nymphonidae. The lecithotrophic postlarvae hatch from the eggs of the callipallenid sea spiders, but the data on this life stage are very scarce and fragmentary. This gives a very limited understanding of larval anatomy, morphology, and diversity.

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The digestive organs are highly sensitive to the influence of orbital flight factors and can limit the professional activities of crew members aboard the International Space Station. Connective tissue, as a system-forming matrix of the integrative-buffer metabolic environment, is of particular relevance in space biomedicine, ensuring the functioning of internal organs under an altered gravitational stimulus. However, the adaptive mechanisms of the fibrous extracellular matrix of the gastric and intestinal connective tissue have not been fully investigated under prolonged microgravity weightlessness.

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Phoxichilidium femoratum is a common species of sea spiders - a small and unique group of chelicerates with unusual adult anatomy. In particular, substantial parts of the reproductive system in pycnogonids (unlike euchelicerates) are located in the appendages. Existing studies of pycnogonid gonads are often limited to light-microscopic level, cover a small range of species, and focus on the contents of the gonad diverticula.

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