102 research outputs found
Принципы хирургического лечения рецидивных грыж пищеводного отверстия диафрагмы (обзор литературы)
Recurrent hiatal hernia is the re-displacement of the abdominal organs into the chest after surgical treatment. Indications for repeated surgical interventions for this pathology are resistant to medical correction gastroesophageal reflux or anatomical disorders, bearing the risk of developing life-threatening conditions. The key task of revision interventions is to identify and address the causes of the failure of the primary operation. The main factors of the recurrence of hernias of this localization are the large size of the hiatal opening, the mechanical weakness of the legs of the diaphragm and the shortening of the esophagus. To increase the reliability of the esophageal aperture plasty in the surgical treatment of recurrent hiatal hernias, prosthetic materials are widely used. When the esophagus is shortened, it is possible to increase its length by creating a gastric stalk (gastroplasty) or fixing the stomach to the anterior abdominal wall (gastropexy). The disadvantage of both methods is the occurring functional impairment. An alternative approach is the formation of a fundoplication wrap in the chest with the closure of the esophageal opening only with its own tissues. To eliminate or prevent the development of gastroesophageal reflux, antireflux reconstruction is an essential component of operations for recurrent hiatal hernias. The option of fundoplication is selected in accordance with the contractility of the esophagus. With normokinesia, circular fundoplication was preferred, with impaired motor skills – free reconstructions.Под рецидивными грыжами пищеводного отверстия диафрагмы понимают любые варианты повторного смещения органов брюшной полости в грудную клетку после хирургического лечения. Показаниями к повторным оперативным вмешательствам при данной патологии являются не поддающийся медикаментозной коррекции гастроэзофагеальный рефлюкс или анатомические нарушения, несущие риск развития угрожающих жизни состояний. Ключевая задача ревизионных вмешательств заключается в выявлении и устранении причин неудачного исхода первичной операции. Основными факторами повторного возникновения грыж данной локализации являются большие размеры хиатального отверстия, механическая слабость ножек диафрагмы и укорочение пищевода. Для повышения надежности пластики пищеводного отверстия диафрагмы при хирургическом лечении рецидивных хиатальных грыж широко используются протезирующие материалы. При укорочении пищевода возможно увеличение его длины созданием желудочного стебля (гастропластика), фиксация желудка к передней брюшной стенке (гастропексия). Недостатком обеих методик являются возникающие функциональные нарушения. Альтернативный подход – формирование фундопликационной манжеты в грудной клетке с закрытием пищеводного отверстия только собственными тканями. Для устранения или профилактики развития желудочно-пищеводного заброса обязательным компонентом операций при рецидивных хиатальных грыжах является антирефлюксная реконструкция. Вариант фундопликации выбирается в соответствии с сократительной способностью пищевода. При нормокинезии предпочтительны циркулярные фундопликации, при нарушениях моторики – свободные реконструкции
Commissioning of the vacuum system of the KATRIN Main Spectrometer
The KATRIN experiment will probe the neutrino mass by measuring the
beta-electron energy spectrum near the endpoint of tritium beta-decay. An
integral energy analysis will be performed by an electro-static spectrometer
(Main Spectrometer), an ultra-high vacuum vessel with a length of 23.2 m, a
volume of 1240 m^3, and a complex inner electrode system with about 120000
individual parts. The strong magnetic field that guides the beta-electrons is
provided by super-conducting solenoids at both ends of the spectrometer. Its
influence on turbo-molecular pumps and vacuum gauges had to be considered. A
system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter
strips has been deployed and was tested during the commissioning of the
spectrometer. In this paper the configuration, the commissioning with bake-out
at 300{\deg}C, and the performance of this system are presented in detail. The
vacuum system has to maintain a pressure in the 10^{-11} mbar range. It is
demonstrated that the performance of the system is already close to these
stringent functional requirements for the KATRIN experiment, which will start
at the end of 2016.Comment: submitted for publication in JINST, 39 pages, 15 figure
Внутрикостная химиотерапия в лечении инвазивного рака мочевого пузыря
Neoadjuvant chemotherapy (CT) with cisplatin administered intraosseously into the pubic bone in patients with invasive bladder carcinoma (Т2—4N0M0) was most effective in patients with circular involvement of the bladder neck, even in large tumors of 5—7 cm. Out of 4 patients with this site of a tumor, full regression without further treatment was achieved in one patient, transurethral resection was performed in 3 patients with 75% tumor regression. In multiple bladder tumor lesions involving the bladder neck, the degree of regression was not greater than 40%. The therapeutic efficiency of intraosseous CT with cisplatin was 54% with acceptable toxicity.
Analysis of LIGO data for gravitational waves from binary neutron stars
We report on a search for gravitational waves from coalescing compact binary
systems in the Milky Way and the Magellanic Clouds. The analysis uses data
taken by two of the three LIGO interferometers during the first LIGO science
run and illustrates a method of setting upper limits on inspiral event rates
using interferometer data. The analysis pipeline is described with particular
attention to data selection and coincidence between the two interferometers. We
establish an observational upper limit of 1.7 \times 10^{2}M_\odot$.Comment: 17 pages, 9 figure
Searching for gravitational waves from known pulsars
We present upper limits on the amplitude of gravitational waves from 28
isolated pulsars using data from the second science run of LIGO. The results
are also expressed as a constraint on the pulsars' equatorial ellipticities. We
discuss a new way of presenting such ellipticity upper limits that takes
account of the uncertainties of the pulsar moment of inertia. We also extend
our previous method to search for known pulsars in binary systems, of which
there are about 80 in the sensitive frequency range of LIGO and GEO 600.Comment: Accepted by CQG for the proceeding of GWDAW9, 7 pages, 2 figure
First upper limits from LIGO on gravitational wave bursts
We report on a search for gravitational wave bursts using data from the first
science run of the LIGO detectors. Our search focuses on bursts with durations
ranging from 4 ms to 100 ms, and with significant power in the LIGO sensitivity
band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than
1.6 events per day at 90% confidence level. This result is interpreted in terms
of the detection efficiency for ad hoc waveforms (Gaussians and sine-Gaussians)
as a function of their root-sum-square strain h_{rss}; typical sensitivities
lie in the range h_{rss} ~ 10^{-19} - 10^{-17} strain/rtHz, depending on
waveform. We discuss improvements in the search method that will be applied to
future science data from LIGO and other gravitational wave detectors.Comment: 21 pages, 15 figures, accepted by Phys Rev D. Fixed a few small typos
and updated a few reference
Setting upper limits on the strength of periodic gravitational waves from PSR J1939+2134 using the first science data from the GEO 600 and LIGO detectors
Data collected by the GEO 600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar's gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar's equatorial ellipticity
Improving the sensitivity to gravitational-wave sources by modifying the input-output optics of advanced interferometers
We study frequency dependent (FD) input-output schemes for signal-recycling
interferometers, the baseline design of Advanced LIGO and the current
configuration of GEO 600. Complementary to a recent proposal by Harms et al. to
use FD input squeezing and ordinary homodyne detection, we explore a scheme
which uses ordinary squeezed vacuum, but FD readout. Both schemes, which are
sub-optimal among all possible input-output schemes, provide a global noise
suppression by the power squeeze factor, while being realizable by using
detuned Fabry-Perot cavities as input/output filters. At high frequencies, the
two schemes are shown to be equivalent, while at low frequencies our scheme
gives better performance than that of Harms et al., and is nearly fully
optimal. We then study the sensitivity improvement achievable by these schemes
in Advanced LIGO era (with 30-m filter cavities and current estimates of
filter-mirror losses and thermal noise), for neutron star binary inspirals, and
for narrowband GW sources such as low-mass X-ray binaries and known radio
pulsars. Optical losses are shown to be a major obstacle for the actual
implementation of these techniques in Advanced LIGO. On time scales of
third-generation interferometers, like EURO/LIGO-III (~2012), with
kilometer-scale filter cavities, a signal-recycling interferometer with the FD
readout scheme explored in this paper can have performances comparable to
existing proposals. [abridged]Comment: Figs. 9 and 12 corrected; Appendix added for narrowband data analysi
Upper limits on the strength of periodic gravitational waves from PSR J1939+2134
The first science run of the LIGO and GEO gravitational wave detectors
presented the opportunity to test methods of searching for gravitational waves
from known pulsars. Here we present new direct upper limits on the strength of
waves from the pulsar PSR J1939+2134 using two independent analysis methods,
one in the frequency domain using frequentist statistics and one in the time
domain using Bayesian inference. Both methods show that the strain amplitude at
Earth from this pulsar is less than a few times .Comment: 7 pages, 1 figure, to appear in the Proceedings of the 5th Edoardo
Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July
200
- …