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41.
BackgroundFlatfoot is a frequent skeletal deformity in childhood that can be minimally invasively treated by arthroereisis. Question: Does the motion of juvenile flexible flatfoot normalize after arthroereisis?MethodPedographic measurements were obtained from 39 patients preoperatively, six months postoperatively and compared to a healthy group. The footprints were divided into 8 areas. The selected parameters were: contact area and force-time-integral.ResultsAfter surgery, a load shift from the medial to the lateral areas was detected under the midfoot and forefoot. The force-time-integral under the hallux normalized. However, under the lateral midfoot, the postoperative force-time-integral was significantly higher than in the control group.SignificanceThe study shows that arthroereisis is able to correct the medially displaced load distribution of juvenile flexible flatfoot. However, further investigations are required to find out if the higher punctual loading under the lateral midfoot may cause problems in the long term.  相似文献   
42.

Methods

The possible association of brain tumour with headache was investigated in 100 patients seen for brain surgery. Preoperatively, 43 patients suffered from headache. These patients were thoroughly questioned about the nature of their pain. Investigation included the McGill Pain Questionnaire.

Results

In only 11 of the patients was headache the primary symptom of a brain tumour. Pain intensity was found to be lower in patients with brain tumour then in those with extracranial tumours or headache of other origins. Female subjects, patients under 50 years of age and those with elevated intracranial pressure experienced more intensive pain. Diurnal variation in pain intensity was observed in 60% of patients with headache. There was no evidence, however, of an association with elevated intracranial pressure.

Conclusions

Our investigations yielded new information concerning the epidemology of headache accompanying brain tumours. Headache is not an early cardinal symptom of brain tumours, as was generally believed earlier. With the help of the McGill Pain Questionnaire a fine quantitative and qualitative characterization of headache of different origins could be made. The connection between tumour localization and pain lateralization, as well as the possible mechanisms of intracranial pain projection was extensively analysed. The interpretations of the results are at best hypotheses and they do not help determine why more than half of the patients with brain tumour did not experience headache.  相似文献   
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In a methodological survey, the technical prerequisites for optimal histopathological diagnosis of gut dysganglionosis are presented. To make a proper diagnosis, the pediatric surgeon or gastroenterologist and the pathologist must consider certain preconditions. The most important steps for the optimal biopsy diagnosis of an aganglionosis, an ultrashort Hirschsprung segment, a intestinal neuronal dysganglionosis (IND), a ganglioneuromatosis, a hypogenesis, or immaturity of the vegetative gut innervation are: (1) taking 3–4 biopsies the size of a peppercorn (3–5 mm3) with submucosa; (2) the best instruments for taking rectal mucosal biopsies are forceps and scissors or a conventional large biopsy forceps; and (3) biopsies may be taken 1 cm, 3–4 cm, 6–9 cm, and 9–12 cm (or from a preternatural anus) above the pectinate line. A biopsy containing mucosa, muscularis mucosae, and submucosa guarantees a satisfying histopathological diagnosis. The native biopsies can be transported on water-ice if the distance to the pathologist takes no longer than 4–6 h. For long distances, biopsies have to be frozen on dry ice (CO2 –80 °C) and transported in a sufficient amount of dry ice (adapted to the time of transportation). For biopsy processing, the following points are important: a total of 122 to 160 15-m-thick native cryostat serial sections have to be cut per biopsy and distributed on four microscope slides. Forty sections are used for lactic dehydrogenase reactions, 32 for succinic dehydrogenase reactions, and the rest for an acetylcholinesterase (AChE) reaction. An AChE reaction alone is sufficient for the diagnosis of Hirschsprung's disease (HD), but never for IND or other developmental malformations of the submucous and myenteric plexuses. Enzymehistotopochemical reactions allow the assessment of functional parameters. These reactions, in contrast to immunohistochemical staining, offer information about the functional activity of special gut structures, e. g., increased AChE activity in nerve fibers of the rectal wall in HD or a lack of dehydrogenase activity in immature ganglia.  相似文献   
45.
Single-channel measurements were performed with the aim of constructing a detailed molecular scheme for the reaction between -aminobutyric acid (GABA) and a chloride channel of crayfish deep extensor abdominal muscle (DEAM). GABA was applied in pulses to outside-out patches of muscle membrane, and, based on the dose-response of the peak currents and of their rise times, a linear model with five binding steps has been proposed. Evaluation of the single-channel kinetics indicated at least three open states. Two of them originate most probably from the fully liganded receptor state and are grouped in mixed bursts due to their different life times. The third one appears independently, outside the bursts, and originates from a lower liganded receptor state. Simulations of the dose-responses and the open time distributions with this model led to a set of rate constants which generated relatively optimal fits.  相似文献   
46.
Twenty-five healthy infants were followed from the newborn period to the age of eighteen months, by evaluation of their neuromotor performance. Evaluation of the specific postural reaction patterns (as described by Vojta) did not seem to be any use as a "short-cut" for the early diagnosis of neuromotor abnormalities, a considerable number of deviations from the normal/optimal pattern being noted even in completely normal infants.  相似文献   
47.
The effects of bezafibrate administered at 10 and 50 mg/kg/day for 7 days to male Sprague-Dawley (SD) and Lewis rats were investigated in order to determine the interrelation between the changes in serum and hepatic lipid contents and activities of selected peroxisomal, microsomal and mitochondrial enzymes in the two rat strains. In both strains, bezafibrate effectively reduced serum and hepatic lipids, increased the liver weight, induced a proliferation of peroxisomes, and selectively elevated the activities of carnitine acetyltransferase and of the enzymes of the peroxisomal -oxidation system. Moreover, immunoblotting revealed that the drug specifically enhanced the concentration of only those peroxisomal enzymes involved in fatty acid -oxidation. The data obtained demonstrate that although the responses initiated by bezafibrate are qualitatively similar in both strains, they differ in their magnitude in a dose-dependent manner, with the Lewis strain exhibiting a more pronounced response than the SD rats. These results show that dose-dependent strain differences as well as the generally known species differences should be taken into account in pharmacological and toxicological evaluations of fibrates in rodents. Furthermore, generalization and extrapolation from rodent studies should be treated with great caution.  相似文献   
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A rapid and sensitive indirect enzyme-linked immunosorbent assay(ELISA) was developed for micrsomal epoxide hydrolase of ratliver. The assay, which is easily and readily performed, issignificantly more sensitive than most enzymatic epoxide hydrolaseassays routinely used and electroimmunoassays previously developed.The limit of sensitivity of the ELISA is between 2–5 ngof microsomal epoxide hydrolase. Using the ELISA microsomalepoxide hydrolases of mouse and rat liver were shown to be antigenicallyvery similar, while microsomal epoxide hydrolases of guineapig, monkey and human liver are antigenically distinct fromthose of rat and mouse. The ELISA developed here is capableof detecting microsomal epoxide hydrolase of rat and mouse livereven when significant enzymatic activity is lost. These resultsindicate that the antigenic sites recognized by the antibodiesused are distinct from the catalytic site of the epoxide hydrolase.Approximately 1.9% of rat microsomal protein was quantifiedas microsomal epoxide hydrolase by the ELISA. Low levels ofmicrosomal epoxide hydrolase were also detected in rat livercytosol (0.02% of the cytosolic protein) demonstrating thatmicrosomal epoxide hydrolase is not totally membrane bound orthat an immunologically related protein occurs in the cytosolof normal rat liver. The ELISA developed here will be valuablein investigating further the role of microsomal epoxide hydrolase.  相似文献   
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