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The correction of hepatopulmonary syndrome (HPS) after liver transplantation (LT) remains controversial. The aims of our study were to: 1) analyze whether LT reverses HPS; 2) note any relationship between HPS and the systemic hemodynamic disturbance; and 3) note changes in circulating sex hormones and the possible association with pulmonary and systemic hemodynamic changes. Systemic hemodynamic parameters, cardiac output and systemic vascular resistance (SVR), sex hormones, and intrapulmonary vasodilatation assessed by contrast transesophageal echocardiography, and gas exchange abnormalities were investigated in 19 patients with advanced cirrhosis prior to and 6 months (176.8+/-30 days) after LT. LT was followed by a marked reduction in cardiac output (6.6+/-1.7 vs 3.5+/-0.5 l/min; p<0.001) and SVR (1039+/-460 vs 1978+/-294 dyn x sec x cm(-5); p<0.005). Before LT, circulating estradiol and progesterone levels were invariably elevated (66+/-22 pg/ml and 1.8+/-1.1 ng/ml, respectively, normal values <31 pg/ml and 0.35 ng/ml, respectively), and dropped after LT (28+/-12 pg/ml p<0.001 and 0.38+/-0.2 ng/ml; p<0.001, respectively). Seventeen of 19 patients had intrapulmonary vasodilatation and increased alveolar-arterial oxygen difference, thereby fulfilling diagnostic criteria for HPS. Patients with HPS presented higher cardiac output (p<0.05), lower SVR (p<0.01), and higher progesterone and estradiol levels than patients without HPS (p<0.05). LT produced normalization of intrapulmonary vasodilatation in all patients. LT normalized hyperdynamic circulation and is a useful therapeutic option in patients with HPS. Normalization of sex hormone levels after LT suggests that they could play a pathogenic role in the development of HPS.  相似文献   
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Cytomegalovirus (CMV) infection remains an important complication of transplantation. The last decade has been characterized by improvements to management that has reduced its morbidity and mortality. The advance has been particularly important in the diagnosis and prevention. Several techniques have been developed that allow the increasingly rapid and sensitive diagnosis. The different preventive strategies include use of appropriate blood products, immune globulin, and antiviral agents either as prophylaxis or pre-emptive therapy. The development of effective oral drugs as valganciclovir also represents a new advance. It is necessary to summarize these advances to facilitate the development of local policies reflecting recent changes. The Group of Study of Infections in Transplantation (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) has therefore produced actual recommendations in the management of CMV infection after transplantation.  相似文献   
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Background

Self-expandable metal stents (SEMSs) can be used for palliation of combined malignant biliary and duodenal obstructions. However, the results of the concomitant stent placement for the duration of the patients’ lives, as well as the need for and efficacy of endoscopic revision, are unclear.

Aim

This study evaluated the clinical effectiveness of SEMS placement for combined biliary and duodenal obstructions throughout the patients’ lives and the need for endoscopic revision.

Methods

This study is a retrospective multicenter study of 50 consecutive patients who underwent simultaneous or sequential SEMS placement for malignant biliary and duodenal obstructions. The data were collected to analyze the sustained relief of obstructive symptoms until the patients’ death and the efficacy of endoscopic revision, as well as stent patency, adverse events, survival and prognostic factors for stent patency.

Results

Technical and immediate clinical success was achieved in all of the patients. Duodenal stricture occurred before the papilla in 35 patients (70 %), involved the papilla in 11 patients (22 %) and was observed distal to the papilla in four patients (8 %). Initial biliary stenting was performed endoscopically in 42 patients (84 %) and percutaneously in eight patients. After combined stenting, 30 patients (60 %) required no additional intervention until the time of their death. The remaining 20 patients were successfully treated using endoscopic stent reinsertion: nine patients needed biliary revision, three patients needed duodenal restenting and eight patients needed both biliary and duodenal reinsertion. The median duodenal stent patency and median biliary stent patency were 34 and 27 weeks, respectively. The median survival after combined stent placement was 18 weeks. A Cox multivariate analysis showed that duodenal stent obstruction after combined stenting was a risk factor for biliary stent obstruction (hazard ratio 6.85; 95 % confidence interval 1.43–198.98; P = 0.025).

Conclusions

Endoscopic bilio-duodenal bypass is clinically effective, and the majority of the patients need no additional intervention until their death. Endoscopic revision is feasible and has a high success rate.  相似文献   
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International Journal of Legal Medicine - Hair shafts are one of the most common types of evidence at crime scenes, and mitochondrial DNA (mtDNA) has been analyzed as a valuable genetic marker for...  相似文献   
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IntroductionThe current paradigm of the management of rheumatoid arthritis (RA) recommends achieving a state of remission or low disease activity through the treat-to-target strategy. Our study assesses adherence to this strategy.MethodPatients with RA (ACR-EULAR 2010 criteria) were included. From each centre, 19 patients were randomly selected. Clinical histories (CH) were assessed by independent auditors, checking compliance with predefined quality criteria. The study was approved by ethics committees.ResultsWe included 856 patients (mean age 54 years; 71% women). The use of a combined index (CI) was recorded in 61% of cases. Visits were recorded every 4 weeks using a CI in 4% of CH while attempts were made to achieve remission. Monitoring of disease activity every 6–8 months after reaching the target was recorded in 73% of cases.ConclusionsThe implementation of the treat-to-target strategy is barely recorded in patients with RA in routine clinical practice.  相似文献   
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The radical copolymerization of N-vinyl-2-pyrrolidone (NVP) with N,N'-dimethylacrylamide (DMAm) has been studied. The copolymer compositions were determined from 1H-NMR. The radical reactivity ratios for DMAm (M1) and VP (M2) were found to be r1 = 2.232 and r2 = 0.186. An analysis of the water vapor absorption isotherms as a function of the lactam content in the copolymer is reported. It was observed that the water vapor absorption decreases with increasing VP content in the copolymer and show anomalous diffusion behavior with increasing temperature due to the coupling of diffusion and polymer relaxation mechanisms. From the water vapor sorption data the Arrhenius activation parameter (ED) and enthalpy of sorption (deltaH S) were determined. The activation parameters are found to follow the conventional trend. The poly(DMAm-co-VP) copolymers exhibited a decreased critical solution temperature (LCST) in proportion to their lactam content. Contact angle data were evaluated for the determination of surface free energy components (gamma d SV, gamma P SV and gamma SV) of the synthesized polymers. The dispersion force component (gamma d SV) of copolymers increased only slightly with the VP content whereas the polar force component (gamma P SV) decreased with the lactam content. No dependence was observed between the surface free energy (gamma SV) and copolymer compositions. The complex formation between bovine serum albumin (BSA) and the VP-DMAm copolymers in water was studied by fluorescence spectroscopy. It was found that the copolymers bind to BSA non-specifically on the surface. Phase separation was not observed after addition of copolymers to BSA solutions at pH higher or lower than isoelectric point of BSA.  相似文献   
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