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1942. Bibliografie české, moravské a slezské archeologie za r. 2000-2001
- Creator:
- Drašnarová, Milada
- Type:
- article and TEXT
- Language:
- Czech and English
- Description:
- Soupis bibliografie
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
1943. Bifurcation of periodic solutions to variational inequalities in $\mathbb{R}^\kappa$ based on Alexander-Yorke theorem
- Creator:
- Kučera, Milan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bifurcation, periodic solutions, variational inequality, differential inequality, finite dimensional space, and Alexander-Yorke theorem
- Language:
- English
- Description:
- Variational inequalities \[ U(t) \in K, (\dot{U}(t)-B_\lambda U(t) - G(\lambda ,U(t)),\ Z - U(t))\ge 0\ \text{for all} \ Z\in \ K, \text{a.a.} \ t\in [0,T) \] are studied, where $K$ is a closed convex cone in $\mathbb{R}^\kappa $, $\kappa \ge 3$, $B_\lambda $ is a $\kappa \times \kappa $ matrix, $G$ is a small perturbation, $\lambda $ a real parameter. The assumptions guaranteeing a Hopf bifurcation at some $\lambda _0$ for the corresponding equation are considered and it is proved that then, in some situations, also a bifurcation of periodic solutions to our inequality occurs at some $\lambda _I \ne \lambda _0$. Bifurcating solutions are obtained by the limiting process along branches of solutions to penalty problems starting at $\lambda _0$ constructed on the basis of the Alexander-Yorke theorem as global bifurcation branches of a certain enlarged system.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1944. Bifurcations for a problem with jumping nonlinearities
- Creator:
- Kárná, Lucie and Kučera, Milan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- nonlinearizable elliptic equations, jumping nonlinearities, global bifurcation, and half-eigenvalue
- Language:
- English
- Description:
- A bifurcation problem for the equation ∆u + λu − αu+ + βu− + g(λ,u)=0 in a bounded domain in N with mixed boundary conditions, given nonnegative functions α, β ∈ L∞ and a small perturbation g is considered. The existence of a global bifurcation between two given simple eigenvalues λ(1), λ(2) of the Laplacian is proved under some assumptions about the supports of the functions α, β. These assumptions are given by the character of the eigenfunctions of the Laplacian corresponding to λ(1), λ(2).
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1945. Bifurcations for Turing instability without SO(2) symmetry
- Creator:
- Ogawa, Toshiyuki and Okuda, Takashi
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- perturbed boundary conditions, imperfect pitchfork bifurcation, and Turing instability
- Language:
- English
- Description:
- In this paper, we consider the Swift-Hohenberg equation with perturbed boundary conditions. We do not a priori know the eigenfunctions for the linearized problem since the SO(2) symmetry of the problem is broken by perturbation. We show that how the neutral stability curves change and, as a result, how the bifurcation diagrams change by the perturbation of the boundary conditions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1946. Bifurcations in the two imaginary centers problem
- Creator:
- Chiralt, Cristina, Campos, Beatriz, and Vindel, Pura
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bifurcation, topological configuration, and orbital structure
- Language:
- English
- Description:
- In this paper we show that, for a given value of the energy, there is a bifurcation for the two imaginary centers problem. For this value not only the configuration of the orbits changes but also a change in the topology of the phase space occurs.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1947. Bifurcations of invariant measures in discrete-time parameter dependent cocycles
- Creator:
- Maltseva, Anastasia and Reitmann, Volker
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- discrete-time parameter-dependent cocycles, Hausdorff dimension estimate, and invariant measure
- Language:
- English
- Description:
- We consider parameter-dependent cocycles generated by nonautonomous difference equations. One of them is a discrete-time cardiac conduction model. For this system with a control variable a cocycle formulation is presented. We state a theorem about upper Hausdorff dimension estimates for cocycle attractors which includes some regulating function. We also consider the existence of invariant measures for cocycle systems using some elements of Perron-Frobenius theory and discuss the bifurcation of parameter-dependent measures.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1948. Bile acids, nuclear receptors and cytochrome P450
- Creator:
- Juřica, J., Dovrtělová, G., Nosková, K., and Zendulka, O.
- Type:
- article, model:article, and TEXT
- Subject:
- Bile acids, FXR, PXR, and Cytochrome P450
- Language:
- English
- Description:
- This review summarizes the importance of bile acids (BA) as important regulators of various homeostatic mechanisms with detailed focus on cytochrome P450 (CYP) enzymes. In the first part, synthesis, metabolism and circulation of BA is summarized and BA are reviewed as physiological ligands of nuclear receptors which regulate transcription of genes involved in their metabolism, transport and excretion. Notably, PXR, FXR and VDR are the most important nuclear receptors through which BA regulate transcription of CYP genes involved in the metabolism of both BA and xenobiotics. Therapeutic use of BA and their derivatives is also briefly reviewed. The physiological role of BA interaction with nuclear receptors is basically to decrease production of toxic non-polar BA and increase their metabolic turnover towards polar BA and thus decrease their toxicity. By this, the activity of some drug-metabolizing CYPs is also influenced what could have clinically relevant consequences in cholestatic diseases or during the treatment with BA or their derivatives.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1949. Bile duct injury during cholecystectomy
- Creator:
- Kapoor, K. V.
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, přehledy, and TEXT
- Subject:
- cholecystektomie laparoskopická--škodlivé účinky--využití, žlučové cesty--zranění, chirurgie žlučových cest--škodlivé účinky--využití, nemoci žlučových cest--chirurgie, peroperační péče--metody, katetrizace--metody--využití, reoperace--využití, pooperační komplikace--etiologie--terapie, zavedení chirurgických vývodů--využití, biliární píštěl, and lidé
- Language:
- Czech and English
- Description:
- Laparoscopic cholecystectomy (LC) is the treatment of choice for gall stones but is associated with an increased risk of bile duct injury (BDI). A BDI detected during LC may be repaired if a biliary surgeon is available but the easiest and safest option for a general surgeon is to place drains in the subhepatic fossa to covert the acute BDI into a controlled external biliary fistula (EBF). Most BDIs are diagnosed in the postoperative period and result in bile leak. Treatment is with percutaneous catheter drainage and endoscopic stenting of the bile duct; early repair is not recommended. Repair, in the form of hepatico-jejunostomy (HJ), should be performed by a biliary surgeon after a delay of 4−6 weeks when the EBF has closed. BDI is a common cause of medico-legal suit and a large burden on healthcare costs. Most BDIs can be prevented by adhering to the principles of safe cholecystectomy., Laparoskopická cholecystektomie (LC) je léčbou volby u žlučových kamenů, avšak je spojená se zvýšeným rizikem poranění žlučových cest (bile duct injury − BDI). Pokud je BDI detekováno během LC, může se řešit ihned, pokud je dostupný hepatobiliární chirurg, ale nejjednodušší a nejbezpečnější postup pro všeobecného chirurga je umístění drénů do podjaterní krajiny a převedení akutní BDI na řízenou zevní biliární píštěl (external biliary fistula − EBF). Většina BDI jsou diagnostikované až v pooperačním období, kdy vzniká biliární leak. Léčbou je drenáž perkutánním katetrem a endoskopické zavedení stentu do žlučovodu; časná reparace se nedoporučuje. Reparace ve formě hepatikojejunostomie (HJ) by měla být provedena hepatobiliárním chirurgem s odstupem 4−6 týdnů poté, co se uzavře EBF. BDI jsou častou příčinou zdravotnicko-právních žalob a významně zatěžují náklady ve zdravotnictví. Většině BDI se dá předejít dodržováním principů bezpečné cholecystektomie., and V. K. Kapoor
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1950. Biliární leak po jaterních resekcích: retrospektivní analýza vlastního souboru
- Creator:
- Menclová, Kateřina, Bělina, František, Pudil, Jiří, Langer, Daniel, and Ryska, Miroslav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- retrospektivní studie, játra--chirurgie, chirurgie trávicího traktu--škodlivé účinky, laparotomie--škodlivé účinky--využití, perioperační péče, pooperační komplikace, index tělesné hmotnosti, rizikové faktory, statistika jako téma, incidence, dospělí, staří, staří nad 80 let, ženské pohlaví, lidé, mužské pohlaví, lidé středního věku, mladý dospělý, nemoci žlučového ústrojí--etiologie--chirurgie, and výsledky a postupy - zhodnocení (zdravotní péče)
- Language:
- Czech and English
- Description:
- Úvod: Existuje mnoho studií věnujících se problematice biliárních komplikací po jaterních resekcích. Přes zlepšení operační techniky a perioperační péče má incidence této komplikace spíše vzrůstající charakter. Byly analyzovány četné prediktivní faktory. Na jejich vliv na vznik biliárního leaku doposud nepanuje shoda. Za cíl analýzy jsme si stanovili zhodnotit incidenci biliárního leaku, jeho vliv na mortalitu a na dobu hospitalizace na našem pracovišti. Současně jsme provedli rozbor známých prediktivních faktorů. Metoda: Autoři retrospektivně analyzují soubor 146 nemocných, u kterých byla na Chirurgické klinice 2. LF Univerzity Karlovy a ÚVN, Praha v období 2010–2013 provedena jaterní resekce. K vyhodnocení biliárního leaku jsme užili současnou uznávanou klasifikaci ISGLS (International Study Group of Liver Surgery). Závažnost komplikace byla stanovena dle Clavien-Dindo. Statistickou významnost prediktivních faktorů jsme určili pomocí Fisherova exaktního testu a Studentova t-testu. Výsledky: Incidence biliárního leaku byla 21 %. Dle ISGLS bylo 6,5 % pacientů zařazeno do skupiny typu A, v 61,2 % se jednalo o leak B a v 32,3 % o leak typu C. Stupeň závažnosti dle Clavien-Dindo I-II, IIIa, IIIb, IV a V byl v poměru 19,3 %, 42 %, 9,7 %, 9,7 %, resp. 19,3 %. Jako statisticky významné jsme stanovili tyto faktory: operaci pro malignitu (p<0,001), velkou jaterní resekci (p=0,001), dobu operace (p<0,001), vyšší peroperační krevní ztrátu (p=0,02), konstrukci HJA (p=0,005), portální venózní embolizaci/two-stage chirurgii (p=0,009) a ASA skóre (p=0,02). Biliární leak významně prodloužil dobu hospitalizace (p<0,001). V souboru pacientů s biliárním leakem byla 23krát vyšší perioperační mortalita (p<0,001) než v souboru bez leaku. Závěr: Biliární leak je jednou z nejzávažnějších komplikací jaterních resekcí. Většina rizikových faktorů je těžko ovlivnitelných a na jejich vliv nepanuje jednoznačná shoda. Incidenci by mohly redukovat diskutované peroperační leak testy. V budoucnu bude třeba dále pracovat na zlepšení perioperačního managementu a techniky k prevenci vzniku této závažné komplikace. V léčbě se uplatňuje multidisciplinární přístup., Introduction: Many previous reports have focused on bile leakage after liver resection. Despite the improvements in surgical techniques and perioperative care the incidence of this complication rather keeps increasing. A number of predictive factors have been analyzed. There is still no consensus regarding their influence on the formation of bile leakage. The objective of our analysis was to evaluate the incidence of bile leakage, its impact on mortality and duration of hospitalization at our department. At the same time, we conducted an analysis of known predictive factors. Method: The authors present a retrospective review of the set of 146 patients who underwent liver resection at the Department of Surgery of the 2nd Faculty of Medicine of the Charles University and Central Military Hospital Prague, performed between 2010−2013. We used the current ISGLS (International Study Group of Liver Surgery) classification to evaluate the bile leakage. The severity of this complication was determined according to the Clavien-Dindo classification system. Statistical significance of the predictive factors was determined using Fisher‘s exact test and Student‘s t-test. Results: The incidence of bile leakage was 21%. According to ISGLS classification the A, B, and C rates were 6.5%, 61.2%, and 32.3%, respectively. The severity of bile leakage according to the Clavien-Dindo classification system – I-II, IIIa, IIIb, IV and V rates were 19.3%, 42%, 9.7%, 9.7%, and 19.3%, respectively. We determined the following predictive factors as statistically significant: surgery for malignancy (p<0.001), major hepatic resection (p=0.001), operative time (p<0.001), high intraoperative blood loss (p=0.02), construction of HJA (p=0.005), portal venous embolization/two-stage surgery (p=0.009) and ASA score (p=0.02). Bile leakage significantly prolonged hospitalization time (p<0.001). In the group of patients with bile leakage the perioperative mortality was 23 times higher (p<0.001) than in the group with no leakage. Conclusion: Bile leakage is one of the most serious complications of liver surgery. Most of the risk factors are not easily controllable and there is no clear consensus on their influence. Intraoperative leak tests could probably reduce the incidence of bile leakage. In the future, further studies will be required to improve the perioperative management and techniques to prevent such serious complications. Multidisciplinary approach is essential in the treatment., and K. Menclová, F. Bělina, J. Pudil, D. Langer, M. Ryska
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public