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81.
In eight of 10 consecutive cases of IgM monoclonal gammopathy of undetermined significance (MGUS), the M-protein had specificity towards various tissues as estimated by direct and indirect immunofluorescence studies of skin and/or sural nerve biopsies. Five of the cases had neuropathy. In three of them, including two siblings with a demyelinating peripheral neuropathy, the IgM was bound to the myelin-associated glycoprotein (MAG) of peripheral nerves. One had axonal neuropathy with IgM activity against the peri- and endoneurium, while another case with post-infectious neuritis had IgM activity against structures in the endoneurium but no IgM autoimmunity in the direct fluorescence test. The latter improved clinically in parallel with a decrease in the M-protein indicating a pathogenetic role of the autoantibody. In three other cases, the IgM was bound to connective tissue structures, two of them also had plasma antibodies against the peri- and endoneurium in the indirect fluorescence test. Finally, two cases showed no reaction of the M-protein against any tissue structures. Since an autoimmune pathogenesis is suspected, the HLA types of seven patients are reported.  相似文献   
82.
83.
In vivo biocompatibility of dextran-based hydrogels   总被引:4,自引:0,他引:4  
Dextran-based hydrogels were obtained by polymerization of aqueous solutions of methacrylated dextran (dex-MA) or lactate-hydroxyethyl methacrylate-derivatized dextran (dex-lactate-HEMA). Both nondegradable dex-MA and degradable dex-lactate-HEMA disk-shaped hydrogels, varying in initial water content and degree of substitution (DS, the number of methacrylate groups per 100 glucose units), were implanted subcutaneously in rats. The tissue reaction was evaluated over a period of 6 weeks. The initial foreign-body reaction to the dex-MA hydrogels was characterized by infiltration of granulocytes and macrophages and the formation of fibrin, and exudate, as well as new blood vessels. This reaction depended on the initial water content as well as on the DS of the hydrogel and decreased within 10 days. The mildest tissue response was observed for the gel with the highest water content and intermediate DS. At day 21 all dex-MA hydrogels were surrounded by a fibrous capsule and no toxic effects on the surrounding tissue were found. No signs of degradation were observed. The initial foreign-body reaction to the degradable dex-lactate-HEMA hydrogels was less severe compared with the dex-MA gels. In general, the size of the dex-lactate-HEMA hydrogels increased progressively with time and finally the gels completely dissolved. Degradation of the dex-lactate-HEMA hydrogels was associated with infiltration of macrophages and the formation of giant cells, both of which phagocytosed pieces of the hydrogel. A good correlation between the in vitro and the in vivo degradation time was found. This suggests that extra-cellular degradation is not caused by enzymes but depends only on hydrolysis of the ester and/or carbonate bonds present in the crosslinks of the hydrogels. After 21 days, the degradable hydrogels, as such, could not be retrieved, but accumulation of macrophages and giant cells was observed, both of which contained particles of the gels intracellularly. As for the dex-MA hydrogels, no toxic effects on the surrounding tissue were found. The results presented in this study demonstrate that dextran-based hydrogels can be considered as biocompatible materials, making these hydrogels attractive systems for drug delivery purposes.  相似文献   
84.
A 30 year old man admitted with a brain stem infarct presented with intellectual deterioration. A diagnosis of systemic lupus erythematosus (S.L.E.) was based on the presence of five A.R.A. criteria :photosensitivity, arthralgia, leukopenia and thrombopenia, false positive syphilitic serology, antinuclear factors on immunofluorescence. A lupus type circulating anticoagulant (L.C.A.) was no longer detected after corticotherapy. This appears to be a case of the "hematologic" form of S.L.E. in which the presence of L.C.A. predisposes towards thrombosis, not only of veins--which is typical--but also of arteries. These may be isolated and reveal the underlying disease as in the present case. The L.C.A. is an antibody possessing antiphospholipid specificity which explains the anticoagulant action in vitro and the thrombogenic effect in vivo. Some authors consider this to be sufficient justification for administration of anticoagulants and/or antiplatelet agents, but corticotherapy may be effective.  相似文献   
85.
Soccer injuries of youth.   总被引:5,自引:4,他引:1       下载免费PDF全文
During a soccer tournament with participation of 6,600 boys and girls (9-19 years) all injuries were evaluated, 5.2% of the players were injured; out of these 51% had "slight injuries", 42% "moderate injuries" and 7% "severe injuries". For the individual player the incidence of injury was 19.1/1,000 playing hours including all degrees of injuries; if "slight injuries" were excluded the incidence was 9.4/1,000 playing hours. The incidence rose with increasing age, girls were injured more often than boys. There were 81% of all injuries localised to the lower extremity, especially the ankle and foot. Contusion was the most frequent diagnosis, amounting to a third of all injuries. Blisters and exoriations amounted to nearly a fifth, 4% of the injuries were fractures, especially in the upper extremity; overuse injuries were seen only in 5.2% of the cases. Based on examination of the injury pattern in these children, injuries of youth seem to be relatively rare and mostly of a non-severe character.  相似文献   
86.
One hundred seventy-three abstinent patients were screened for phobias and avoidant personality disorder. Ninety-six patients were interviewed and diagnosed by two independent assessors who were in agreement on 74% of the diagnoses. In DSM-III terms, over half of the sample (51.4%) met criteria for agoraphobia (8.5%), social phobia (7.8%) and avoidant personality disorder (35.1%). More than 70% of the patients in each diagnostic category were men. For the vast majority of the patients in the sample the disorder preceded the abuse of alcohol which was used by at least 40% of them to relieve their distress in the past. For many it had still a moderating effect on distress at the present but appeared to be mainly used out of "psychological dependence".  相似文献   
87.
Although a rare complication, the development of a urethro-perineal urinary fistula immediately after abdomino-perineal amputation is a difficult problem to solve. The fragility of the membranous urethra immediately in contact with the exenterated pelvic cavity which takes several weeks to fill in makes any attempt at isolated direct suture very hazardous. Secondary repair is also frequently difficult and the "functional prognosis is far from being always favourable". The major handicap resulting from the perpetuation of this type of fistula has led us to propose an attempt at immediate repair as soon as it is diagnosed with filling of the pelvi-perineal cavity by a cutaneo-muscular flap taken from gluteus maximus. In the two cases in which this treatment was performed, the fistula was cured and a good quality functional result was obtained.  相似文献   
88.
The hypothesis was postulated that various subpopulations may be represented in samples of fish living in an open fjord system. A statistical model based on mercury and octachlorostyrene concentrations in cod from two monitoring programs in a Norwegian fjord, was applied to test the hypothesis. The model was (mercury concentration) = b · (weight), where the coefficient b reflects the mercury concentration in the environment and to is the weight exponent. The effects of weight, time, and sex were considered. The distributions of b values, or normalized b values, were investigated by the normal plot technique. Discontinuities in the graphs were interpreted as indicative of the presence of two subpopulations. Weight-independent concentration ratios were also used in the classification of the fish on the octachlorostyrene data. The two subgroups were the same as those revealed by the mercury data. The statistical analysis of mercury and octachlorostyrene data supported the hypothesis that different subpopulations may be represented in samples of fish found in the present and similar fiord systems. The size of a fish sample must permit the testing of a general hypothesis of nonuniform distribution of concentrations of pollutants in the fish.  相似文献   
89.
Maternal and Child Health Journal - Dietary patterns can influence maternal and child health outcomes. The study aims to characterize dietary patterns during pregnancy as well as to identify their...  相似文献   
90.
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.  相似文献   
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