1,160 research outputs found
Anatomy of the supraventricular crest in human hearts
The supraventricular crest is a fleshy trabecula of the right ventricle that has an
important function in guiding the blood flow. However, controversy persists
regarding its anatomical constitution. In this study, we aimed to investigate its
frequency, formation, termination, morphometry, and relationships with the
septomarginal trabecula, septal papillary muscle, right atrioventricular ring, and
left posterior semilunar valve of the pulmonary trunk valve. Our material consisted
of 50 hearts from adult individuals of both sexes that had been preserved
in 10% formalin. They were opened along the arterial cone by means of
an incision starting at the pulmonary trunk and ending at the right margin. The
supraventricular crest was always present. The marginal (right) extremity was
formed by two to six muscle bundles that joined together (88%). On the septal
(left) side, the single muscle bundle penetrated the interventricular septum
directly (88%) or by means of two or three divisions (12%). It could form
a septal band (52%) and could pass over the septal papillary muscle (43.5%) or
just below it (34.8%). There was a relationship of muscle fibres between these
two structures in 64% of cases. Dissection of the septal band demonstrated
continuity with the septomarginal trabecula (46%). In 80% of cases, the crest
was connected to the right atrioventricular ring and it participated in its outline
directly (64%) or by means of muscle expansions (16%). Its muscle fibres bordered
the left semilunar valve of the pulmonary valve in 50% of cases. Regarding
morphometry, we observed that the length varied little with increasing
weight of the heart (22.6%), but the height and width increased markedly with
increasing weight of the heart. Folia Morphol 2010; 69, 1: 42-4
The subscapular artery and the thoracodorsal branch: an anatomical study
The motive for this research was the use of the muscles of the scapular region
in transposition, transplantation and reparative surgery and the need for more
detailed knowledge of the blood supply to these muscles. In addition, the subscapular
arterial tree may be used as a source of microvascular grafts to replace
damaged or diseased portions of arteries, particularly in the hand and forearm.
The research was conducted on 60 sides of corpses of adults of both sexes.
It was noticed that the subscapular artery was present in 96.7% of cases and
originated laterally to the pectoralis minor muscle in 76.7% of cases. The average
calibre was 5.0 mm, and in 73.2% of cases it measured between 4.0 and
5.9 mm. The average length was 18.0 mm, ranging from 10.0 to 29.9 mm
(76.7%). It presented in its course important relations with the axillary nerve
(69%) and with the radial nerve (82.8%). Its branches were collateral (subscapular
muscle - 61.3%) and terminal (except for the circumflex scapular artery),
leading to the following muscles: serratus anterior (43.9%), latissimus dorsi
(27.6%), and subscapular (23.3%). The thoracodorsal artery, one of the terminal
branches, most frequently showed a calibre of between 2.0 and 3.9 mm
(70.3%), collateral branches in 85.0%, was mainly distributed to the subscapular
muscle (36.7%) and to the serratus anterior muscle (29.0%) and had terminal
branches to the following muscles: latissimus dorsi (44.1%), serratus anterior
(40.5%) and the subscapular (12.5%). The serratus anterior muscle received
one branch in 39.5% and two branches in 41.9%, while the latissimus dorsi
muscle received one branch in 66.7% and two branches in 23.1%. (Folia Morphol
2008; 67: 58-62
The anatomy of the human thyroid veins and its surgical application
The present study was motivated by the importance of the thyroid veins in
surgery in the anterolateral cervical region, particularly in tracheostomies, the
need for information on modern diagnostic imaging techniques and the lack
of specific publications on the subject. The research was performed on 30 adult
human specimens by means of dissection and measurement. The superior thyroid
vein was constant, single on both sides (83.3%), with its termination (87.1%)
at the internal jugular vein (97.2%), either isolated (29.4%) or with other veins,
mostly the lingual vein (52.1%), and was located between 1.0 and 2.5 cm
below a plane that passes the upper margin of the hyoid bone. The medial
thyroid vein, when present, was not constant (43.3%), was single (96.1%),
terminated in the internal jugular vein and was located between 2.0 and 4.0 cm
from the mid-sagittal line (84.6%). The inferior thyroid vein was constant (96.7%)
and varied in number, with one (62.1%), two (27.6%) or even five occurring,
and was formed by the confluence of two primary branches (78.6%) as a result
of the abundance of anastomoses coming from the lower and medial parts of
the gland. The number of terminations corresponded to the number of veins,
at the level of the 5th to 8th rings in 36.9%, of the 9th to 10th rings in 34.8% and
of the 11th to 14th rings in 28.3%, and occurred in the right brachiocephalic
vein (26.1%), in the left brachiocephalic vein (60.9%) or in both veins (13.0%)
Electronic Structure of Transition-Metal Dicyanamides Me[N(CN)] (Me = Mn, Fe, Co, Ni, Cu)
The electronic structure of Me[N(CN)] (Me=Mn, Fe, Co, Ni, Cu)
molecular magnets has been investigated using x-ray emission spectroscopy (XES)
and x-ray photoelectron spectroscopy (XPS) as well as theoretical
density-functional-based methods. Both theory and experiments show that the top
of the valence band is dominated by Me 3d bands, while a strong hybridization
between C 2p and N 2p states determines the valence band electronic structure
away from the top. The 2p contributions from non-equivalent nitrogen sites have
been identified using resonant inelastic x-ray scattering spectroscopy with the
excitation energy tuned near the N 1s threshold. The binding energy of the Me
3d bands and the hybridization between N 2p and Me 3d states both increase in
going across the row from Me = Mn to Me = Cu. Localization of the Cu 3d states
also leads to weak screening of Cu 2p and 3s states, which accounts for shifts
in the core 2p and 3s spectra of the transition metal atoms. Calculations
indicate that the ground-state magnetic ordering, which varies across the
series is largely dependent on the occupation of the metal 3d shell and that
structural differences in the superexchange pathways for different compounds
play a secondary role.Comment: 20 pages, 11 figures, 2 table
Allogeneic stem cell transplantation (SCT) for the treatment of 15 patients with paroxysmal nocturnal hemoglobinuria (PNH) in Brazil
Bone Marrow Transplantation (BMT) for heavily Transfused Patients (pts) with Severe Aplastic Anemia (SAA): 147 pts treated at the same institution with Busulfan (BU) + Cyclophosphamide (CY)
Stem cell transplantation in 40 pts with Fanconi anemia (FA): Excellent survival and low toxicity for pts with a related HLA identical donor
Univ Fed Parana, BR-80060000 Curitiba, Parana, BrazilEPM, Inst Oncol Pediat, São Paulo, BrazilEPM, Inst Oncol Pediat, São Paulo, BrazilWeb of Scienc
Symmetry preserving regularization with a cutoff
A Lorentz and gauge symmetry preserving regularization method is proposed in
4 dimension based on momentum cutoff. We use the conditions of gauge invariance
or freedom of shift of the loop-momentum to define the evaluation of the terms
carrying Lorentz indices, e.g. proportional to k_{\mu}k_{\nu}. The remaining
scalar integrals are calculated with a four dimensional momentum cutoff. The
finite terms (independent of the cutoff) are unambiguous and agree with the
result of dimensional regularization.Comment: 12 pages, 1 figure, v2 references adde
New improved Moser-Trudinger inequalities and singular Liouville equations on compact surfaces
We consider a singular Liouville equation on a compact surface, arising from
the study of Chern-Simons vortices in a self dual regime. Using new improved
versions of the Moser-Trudinger inequalities (whose main feature is to be
scaling invariant) and a variational scheme, we prove new existence results.Comment: to appear in GAF
A novel way of constraining WIMPs annihilations in the Sun: MeV neutrinos
Annihilation of dark matter particles accumulated in the Sun would produce a
flux of high-energy neutrinos whose prospects of detection in neutrino
telescopes and detectors have been extensively discussed in the literature.
However, for annihilations into Standard Model particles, there would also be a
flux of neutrinos in the MeV range from the decays at rest of muons and
positively charged pions. These low-energy neutrinos have never been considered
before and they open the possibility to also constrain dark matter annihilation
in the Sun into e+e-, mu+mu- or light quarks. Here we perform a detailed
analysis using the recent Super-Kamiokande data in the few tens of MeV range to
set limits on the WIMP-nucleon scattering cross section for different
annihilation channels and computing the evaporation rate of WIMPs from the Sun
for all values of the scattering cross section in a consistent way.Comment: 26 pages, 7 figures. Substantial additions with further explanations.
Two significant improvements: in the calculation of the evaporation and
capture rates; and in the analysis of the SK data. Minor changes in the
conclusions. It matches published versio
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