485 research outputs found
49. Radykalność onkologiczna a operacje oszczędzające zwieracze (CS) w leczeniu raka odbytnicy
Wyniki leczenia raka odbytnicy są zależne od wielu czynników, w tym obejmujących taktykę operacyjną oraz neo i adjuwancyjne leczenie skojarzone. Operacje oszczędzające zwieracze odbytu (CS) są obecnie wykonywane coraz częściej, a wskazania obejmują również lokalizację w dolnej części odbytnicy.Celem pracy była ocena własnych wyników w kategoriach radykalności onkologicznej zależnej od modelu leczenia tj. radykalnego odjęcia brzuszno-kroczowego w porównaniu z operacjami oszczędzającymi zwieracze odbytu.MateriałW latach 1984–2002 było leczonych operacyjnie n = 1671 chorych z rakiem jelita grubego, w tym chorych = 859 chorych z rakiem odbytnicy i 56 z wielomiejscowym zaawansowanym rakiem odbytnicy i okrężnicy. Operacje oszczędzające zwieracze odbytu (CS) wykonano u 51.7% chorych. W całej grupie leczonych uzyskano poziom resekcyjności 93.8%. Adjuwancyjnej chemioterapii, poddano wszystkich chorych (spełniających kryteria włączenia z uwagi na stan ogólny, wiek < 75 r.ż) w grupie II,III i IV stopniu zaawansowania wg UICC/AJCC. Neoadjuwancyjnej radio- lub radiochemioterapii poddano n = 98 chorych z rakiem odbytnicy w II lub III stopniu zaawansowania wg.UICC/AJCC. W dwóch różnych okresach analizy stosowano 2 modele usunięcia węzłów chłonnych – standardowy model D1/D2 w latach 1984–1991 oraz model D3 w latach 1982–2002 podczas operacji resekcyjnych.WynikiUzyskano poziom 5-cio letnich przeżyć ogółem 57 %. Przeprowadzono analizę regresyjną Coxa celem określenia wartości poszczególnych czynników prognostycznych. W całej grupie leczonych najważniejsze znaczenie miały takie czynniki jak: zaawansowanie choroby wg. UICC (w kolejności cech M,T,N) oraz zakres wycięcia układu chłonnego, a następnie stosowanie leczenia skojarzonego. Wykazano lepsze wyniki u chorych z operacjami oszczędzającymi zwieracze odbytu (CS). Wysoki odsetek operacji odjęcia brzuszno–kroczowego był związany z miejscowym zaawansowaniem raka i radykalizacją leczenia chirurgicznego.WnioskiWykazana analiza wskazuje na zależność nie tylko stopnia zaawansowania choroby, ale również od roli chirurgii oraz leczenia skojarzonego jako podstawowych czynników poprawiających wyniki w leczeniu raka odbytnicy
Complex network analysis of literary and scientific texts
We present results from our quantitative study of statistical and network
properties of literary and scientific texts written in two languages: English
and Polish. We show that Polish texts are described by the Zipf law with the
scaling exponent smaller than the one for the English language. We also show
that the scientific texts are typically characterized by the rank-frequency
plots with relatively short range of power-law behavior as compared to the
literary texts. We then transform the texts into their word-adjacency network
representations and find another difference between the languages. For the
majority of the literary texts in both languages, the corresponding networks
revealed the scale-free structure, while this was not always the case for the
scientific texts. However, all the network representations of texts were
hierarchical. We do not observe any qualitative and quantitative difference
between the languages. However, if we look at other network statistics like the
clustering coefficient and the average shortest path length, the English texts
occur to possess more clustered structure than do the Polish ones. This result
was attributed to differences in grammar of both languages, which was also
indicated in the Zipf plots. All the texts, however, show network structure
that differs from any of the Watts-Strogatz, the Barabasi-Albert, and the
Erdos-Renyi architectures
Auswirkungen der Rohproteinversorgung auf die Qualität von Schweinefleisch
The current experiment was conducted to specify the effect of different diets on the quality of pork with emphasis on the intramuscular fat content in the M. longissimus. The results confirm the preliminary conclusions of a former experiment that it is possible to affect the amount of intramuscular fat content by a feeding strategy adapted to the organic framework conditions without increasing the overall fat content of the carcass
QSAR studies on a number of pyrrolidin-2-one antiarrhythmic arylpiperazinyls
The activity of a number of 1-[3-(4-arylpiperazin-1-yl)propyl]pyrrolidin-2-one antiarrhythmic (AA) agents was described using the quantitative structure–activity relationship model by applying it to 33 compounds. The molecular descriptors of the AA activity were obtained by quantum chemical calculations combined with molecular modeling calculations. The resulting model explains up to 91% of the variance and it was successfully validated by four tests (LOO, LMO, external test, and Y-scrambling test). Statistical analysis shows that the AA activity of the studied compounds depends mainly on the PCR and JGI4 descriptors
A cholesterol analog stabilizes the human β2-adrenergic receptor nonlinearly with temperature
In cell membranes, G protein-coupled receptors (GPCRs) interact with cholesterol, which modulates their assembly, stability, and conformation. Previous studies have shown how cholesterol modulates the structural properties of GPCRs at ambient temperature. Here, we characterized the mechanical, kinetic, and energetic properties of the human beta(2)-adrenergic receptor (beta(2)AR) in the presence and absence of the cholesterol analog cholesteryl hemisuccinate (CHS) at room temperature (25 degrees C), at physiological temperature (37 degrees C), and at high temperature (42 degrees C). We found that CHS stabilized various structural regions of beta(2)AR differentially, which changed nonlinearly with temperature. Thereby, the strongest effects were observed for structural regions that are important for receptor signaling. Moreover, at 37 degrees C, but not at 25 degrees or 42 degrees C, CHS caused beta(2)AR to increase and stabilize conformational substates to adopt to basal activity. These findings indicate that the nonlinear, temperature-dependent action of CHS in modulating the structural and functional properties of this GPCR is optimized for 37 degrees C.Peer reviewe
Non-operative management of posterior tibialis tendon dysfunction: design of a randomized clinical trial [NCT00279630]
BACKGROUND: Posterior tibialis tendon dysfunction (PTTD) is a common cause of foot pain and dysfunction in adults. Clinical observations strongly suggest that the condition is progressive. There are currently no controlled studies evaluating the effectiveness of exercise, orthoses, or orthoses and exercise on Stage I or IIA PTTD. Our study will explore the effectiveness of an eccentric versus concentric strengthening intervention to results obtained with the use of orthoses alone. Findings from this study will guide the development of more efficacious PTTD intervention programs and contribute to enhanced function and quality of life in persons with posterior tibialis tendon dysfunction. METHODS/DESIGN: This paper presents the rationale and design for a randomized clinical trial evaluating the effectiveness of a treatment regime for the non-operative management of Stage I or IIA PTTD. DISCUSSION: We have presented the rationale and design for an RCT evaluating the effectiveness of a treatment regimen for the non-operative management of Stage I or IIA PTTD. The results of this trial will be presented as soon as they are available
Topological insulator and quantum memory
Measurements done on the quantum systems are too specific. Contrary to their
classical counterparts, quantum measurements can be invasive and destroy the
state of interest. Besides, quantumness limits the accuracy of measurements
done on quantum systems. Uncertainty relations define the universal accuracy
limit of the quantum measurements. Relatively recently, it was discovered that
quantum correlations and quantum memory might reduce the uncertainty of quantum
measurements. In the present work, we study two different types of measurements
done on the topological system. Namely, we discuss measurements done on the
spin operators and the canonical pair of operators: momentum and coordinate. We
quantify the spin operator's measurements through the entropic measures of
uncertainty and exploit the concept of quantum memory. While for the momentum
and coordinate operators, we exploit the improved uncertainty relations. We
discovered that quantum memory reduces the uncertainties of spin measurements.
On the hand, we proved that the uncertainties in the measurements of the
coordinate and momentum operators depend on the value of the momentum and are
substantially enhanced at small distances between itinerant and localized
electrons (the large momentum limit). We note that the topological nature of
the system leads to the spin-momentum locking. The momentum of the electron
depends on the spin and vice versa. Therefore, we suggest the indirect
measurement scheme for the momentum and coordinate operators through the spin
operator. Due to the factor of quantum memory, such indirect measurements in
topological insulators have smaller uncertainties rather than direct
measurements
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