1. elektronické vydání 1 online zdroj (350 stran)
Československá společnost procházela po komunistickém převratu v únoru 1948 velmi obtížnou etapou, v níž probíhala rozsáhlá sociální transformace, celková přestavba ekonomiky a instalace pevné diktatury jedné strany. Kolektivizace venkova představuje jednu z charakteristických událostí tohoto období. Autor zpracovává téma v regionálním rozměru horního Polabí, v prostoru mezi Hradcem Králové a Krkonošemi. Nahlíží jej z mikrohistorické perspektivy - zajímá se především o aktéry a jejich motivace. Zkoumá, jak byla myšlenka kolektivního obdělávání půdy v letech 1945-1953 ve společnosti přijímána, jaké reakce kolektivizační úsilí vyvolávalo, jaké pohnutky a okolnosti za těmito reakcemi stály a jaké sociální souvislosti, vztahy a vzorce chování se skrývaly za konkrétním jednáním aktérů. V hlavních třech oddílech knížky sleduje fenomény odporu, dobrovolnosti a spolupráce při prosazování kolektivního hospodaření.; Československá společnost procházela po komunistickém převratu v únoru 1948 velmi obtížnou etapou, v níž probíhala rozsáhlá sociální transformace, celková přestavba ekonomiky a instalace pevné diktatury jedné strany. Kolektivizace venkova představuje jednu z charakteristických událostí tohoto období. Autor zpracovává téma v regionálním rozměru horního Polabí, v prostoru mezi Hradcem Králové a Krkonošemi. Nahlíží jej z mikrohistorické perspektivy – zajímá se především o aktéry a jejich motivace. Zkoumá, jak byla myšlenka kolektivního obdělávání půdy v letech 1945–1953 ve společnosti přijímána, jaké reakce kolektivizační úsilí vyvolávalo, jaké pohnutky a okolnosti za těmito reakcemi stály a jaké sociální souvislosti, vztahy a vzorce chování se skrývaly za konkrétním jednáním aktérů. V hlavních třech oddílech knížky sleduje fenomény odporu, dobrovolnosti a spolupráce při prosazování kolektivního hospodaření.
PURPOSE OF THE STUDY The paper aimed to evaluate the long-term outcomes of the treatment of diaphyseal femur fractures in children treated with Bryant's vertical traction. Moreover, we also assessed the size of overgrowth in the injured femur. MATERIAL AND METHODS The study included 23 patients with 23 femoral shaft fractures treated with Bryant's vertical traction at our department in 2009-2014. The following parameters were assessed: sex, ïnjured side, weight, age, mechanism of injury, potential abuse, type of fracture, duration of traction, and total length of hospital stay. The healing time of the fracture was the same as the duration of traction. Also assessed was the size of femoral shortening after the removal of traction, the presence of skin complications in the course of treatment and potential development of compartment syndrome. At the mean follow-up of 47.8 months (range 22-85 months) from the date of injury the patients were evaluated clinically and radiologically for: length of limbs, presence of rotational deformity, range of motion of knee and hip joints, potential pain or limping, potential scoliosis of the spine and presence of scars after traction. Finally, through a questionnaire we learned about the opinions of parents as to the treatment method and about the possibility of home traction. RESULTS All the fractures healed. There was a total of 17 injured boys and 6 injured girls. Whereas 12 patients sustained a fracture of the left femur, 11 patients sustained a fracture of the right femur. The mean weight of patients at the time of injury was 13.9 kg (range 5-20 kg). The mean age at the time of traction was 30.8 months (range 1-70 months). The injury most frequently occurred from various falls, altogether in 15 cases (65.2%). Traffic accidents were registered as the cause of injury in 3 cases (13%). No abuse was confirmed. The average duration of traction was 19.8 days (range 8-26 days). The total length of hospital stay took on average 23.6 days (range 9-33 days). Skin excoriation and bullae due to irritation by the traction occurred in 21 children (91.3% cases). All the bullae healed, in 4 (17.4%) patients minor scars of 1x1 cm in size were formed around ankles. Not a single patient developed the compartment syndrome. The average femoral shortening after the removal of traction was 0.8 cm (range 0-2.3 cm). The follow-up examination, performed on average 47.8 months (range 22-85 months) from the date of injury revealed the average discrepancy of spinomalleolar distances in both the lower limps of 0 cm (range -1 to 1 cm). Radiographically measured lengths of both the femurs showed the average difference of 0 cm (range -1.4 to 0.9 cm). The resulting average overgrowth of injured femur was 0.9 cm (range 0.1 to 3.2 cm). Scoliosis of the spine was not reported in any of the patients. In 3 patients femur alignment demonstrated rotation, namely an external rotation of 10° in all the cases. All the children demonstrated full hip and knee joint mobility, identical to the uninjured side. After a heavy load one patient reported pain in the thigh and one walked with limp. The other patients showed no problems whatsoever. Treatment with the use of Bryant's traction was well tolerated by parents. Altogether 15 parents (65.2%) would opt for the same treatment method in case of a recurrent injury. The home traction option would be welcomed by 17 parents (73.9%). DISCUSSION The treatment by Bryant's vertical traction is condemned in Anglo-Saxon countries due to the risk for developing compartment syndrome, described in earlier studies. Neither our cohort, nor more recent studies reported the occurrence of compartment syndrome. The most frequent complication faced in our study was the skin complications underneath the traction, namely in a total of 91.3% of patients. In the literature, the other authors only make references to bullae occurrence, but do not provide any further specifications. Overgrowth after femoral shaft fractures is a very well described phenomenon. The size of femoral overgrowth described in our study was similar to that referred to in the available literature. A method frequently used abroad is the so-called home traction. This method, however, has so far failed to take root in our country, even though this therapeutic technique would be appreciated by parents. CONCLUSIONS The treatment of femoral shaft fractures by Bryant's vertical traction, in children up to the weight of 15 kg, is a simple and safe method with excellent functional outcomes and minimum serious complications. When treating the children with the body weight more than 15 kg, the risk of bullae formation increases, therefore in this weight category treatment shall be decided upon on a case by case basis. The resulting average overgrowth of injured femur was 0.9 cm which corresponds with the findings of other authors. The treatment method using the Bryant's traction is well tolerated by parents, even though most of them would welcome the option of home traction. Key words: traction, femur fracture, overgrowth, children.
- MeSH
- délka pobytu MeSH
- dítě MeSH
- dopravní nehody MeSH
- fraktury femuru terapie MeSH
- kojenec MeSH
- lidé MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- trakce metody MeSH
- výsledek terapie MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
A chromatographic characterization of pore volume accessibility for both particulate and monolithic stationary phases is presented. Size-exclusion calibration curves have been used to determine the pore volume fraction that is accessible for six alkylbenzenes and twelve polystyrene standards in tetrahydrofuran as the mobile phase. Accessible porosity has been then correlated with the size of the pores from which individual compounds are just excluded. I have determined pore volume accessibility of commercially available columns packed with fully and superficially porous particles, as well as with silica-based monolithic stationary phase. I also have investigated pore accessibility of polymer-based monolithic stationary phases. Suggested protocol is used to characterize pore formation at the early stage of the polymerization, to evaluate an extent of hypercrosslinking during modification of pore surface, and to characterize the pore accessibility of monolithic stationary phases hypercrosslinked after an early termination of polymerization reaction. Pore volume accessibility was also correlated to column efficiency of both particulate and monolithic stationary phases.
The polarity of (poly)methacrylate monolithic capillary columns was varied by using alkylmethacrylate monomers with butyl, cyclohexyl, 2-ethylhexyl, lauryl, and stearyl functional groups in the polymerization mixture. The hydrodynamic properties, as well as the retention characteristics in RP-LC of small molecules (alkylbenzenes) and of proteins under gradient elution conditions were studied. The RP selectivity depends on the type of alkyl chain in methacrylate monomer; however, there was no direct correlation between the size of the monomer molecule and methylene or aromatic selectivity of the monlithic column. The lowest selectivity was found for column based on lauryl methacrylate monomer. On the other hand, butyl methacrylate column shows high phenyl selectivity and the column with stearyl methacrylate possesses the highest methylene selectivity for small molecules. The retention increases with longer alkyl chain in methacrylate monomer, especially for high molar mass proteins on all prepared columns and showed gradient elution behavior of proteins in agreement with the linear solvent strength gradient model. The poly(laurylmethacrylate) column showed lowest hydrophobicity but best efficiency for proteins of all columns tested.
The type of the stationary phase for reversed-phase liquid chromatography significantly affects the sample elution. Hydrodynamic properties, efficiency and gradient elution of proteins were investigated on five commercial C18 columns with wide-pore totally porous particles, with superficially porous layer particles, non-porous particles and a silica-based monolithic bed. The efficiency in the terms of reduced plate height is higher for low-molecular ethylbenzene than for proteins, but depends on the character of the pores in the individual columns tested. The superficially porous Poroshell and the non-porous Micra columns provide the best efficiency for proteins at high mobile phase flow rates, probably because of similar pore architecture in the stationary phase. The Zorbax column with similar pore architecture as the Poroshell active layer, i.e. narrow pore distribution of wider pores shows better efficiency than the packed column with narrow pores and broad pore distribution. The monolithic column shows lower efficiency for proteins at high flow rates, but it performs better than the broad-pore distribution totally porous particulate columns. Different pore architecture affects also the retention and selectivity for proteins on the individual columns. The retention times on all columns can be predicted using the model for reversed-phase gradient elution developed originally for low-molecular compounds. Consideration of the limited pore volume accessible to the biopolymers has negligible effect on the prediction of retention on the columns packed with non-porous or superficially porous particles, but improves the accuracy of the predicted data for the totally porous columns with broad pore distribution.
- MeSH
- algoritmy MeSH
- chemické modely MeSH
- financování organizované MeSH
- hydrofobní a hydrofilní interakce MeSH
- inzulin normy MeSH
- lidé MeSH
- peptidy analýza chemie izolace a purifikace MeSH
- poréznost MeSH
- proteiny analýza chemie izolace a purifikace MeSH
- reprodukovatelnost výsledků MeSH
- sérový albumin normy MeSH
- trypsin normy MeSH
- velikost částic MeSH
- vysokoúčinná kapalinová chromatografie metody přístrojové vybavení MeSH
- Check Tag
- lidé MeSH
The main factors affecting the mesopore porosity of methacrylate-ester based monolithic columns were investigated. We prepared 40 monolithic capillary columns with porosity controlled by varying the proportions of butyl methacrylate (BMA) and ethylene dimethacrylate (EDMA) monomers and of 1,4-butanediol (BUT) and 1-propanol (PROP) as the porogen solvent in the polymerisation mixtures by thermally initiated in situ polymerisation in fused-silica capillaries. Using mixture design software, we systematically varied the composition of the polymerisation mixtures to find significant factors affecting mesopore formation. Multivariate analysis of the experimental data obtained for the fabricated columns yielded a model for prediction of the mesopore porosity in monolithic beds as a function of the composition of the polymerisation mixture used to prepare polymethacrylate monolithic capillary columns. The mean absolute deviation of predicted porosities is 0.029 for most of the columns, with only eight columns showing deviations exceeding 0.050. The main factor affecting the mesopore porosity proved to be the combination of the concentration of hydrophobic monomer (BMA) and the concentration of the less-polar solvent, 1-propanol, in the porogen mixture. The proportion of mesopores in the monolithic capillary columns increases with increasing concentration of 1-propanol and with decreasing concentration ratios of the cross-linker (EDMA) to monomer (BMA) and of BUT to PROP porogenic solvents.