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31.
The classification of some of the extractable birch pollen antigens as allergens was established by crossed radioimmunoelectrophoresis (CRIE). In CRIE the major allergen (antigen 23) exhibited the strongest “radiostaining” and only a few other components of birch pollen extract were visibly radiostained. The major allergen and a preparation containing mainly the minor allergens, antigens 25 and 19, were isolated from a crude aqueous birch pollen extract by a combination of anion-exchange, size-exclusion, and chelate chromatography. Antigen 23 was purified to near homogeneity. The molecular weights and the pIs of antigens 23, 25, and 19 were determined to be 17,000 daltons, pI 5.25 (5.5, 5.0); 25,000 daltons, pI 5.0 (4.9, 5.4); and 29,000 daltons, pI 6.2 (5.4), respectively. The classification of antigen 23 as the major allergen in birch pollen was supported by results of RAST inhibition experiments, RAST screening, and skin prick testing.  相似文献   
32.
We examined 26 individuals with clinical and electron microscopic signs of late infantile neuronal ceroid lipofuscinosis (LINCL). In 22 cases, we found both pathogenic alleles. Sixteen patients exclusively carried either one or a combination of the two common mutations R208X and IVS5-1G > C. In the remaining cases, four missense mutations could be detected, of which R127Q, N286S, and T353P represent novel, previously not described alleles. A clinical performance score was developed by rating motor, visual, and verbal functions and the incidence of cerebral seizures in 3-month intervals during the course of the disease. A Total Disability Score was derived by summing up the single scores for motor, visual, and verbal functions. The 16 individuals with the two common mutations were grouped together (referred to as standard patients), and the 5th, 50th, and 95th centiles were calculated and graphically depicted over time. The scores for motor function and language ability dropped earliest and progressed very similarly in the standard patients. The performance curves of two children with the N286S mutation slightly diverged from the 95th centile. However, the performance curves of one patient with atypical LINCL carrying the R127Q mutation fell far beyond the 95th centile. The presented performance rating clearly and quantitatively delineates the disease course of the LINCL patients and hence offers a useful tool for clinical evaluation of future therapeutic interventions. In addition, the described performance score system can be applied to other types of neuronal ceroid lipofuscinoses and could be adapted to various other neurodegenerative diseases of childhood.  相似文献   
33.
BACKGROUND: The development of occupational asthma and allergic skin reactions caused by natural rubber latex (NRL) allergy are risks for health care workers. There are few published studies to suggest that intervention programs to reduce exposure will lead to primary prevention of sensitization. OBJECTIVE: This study assesses the effects of intervention to reduce the incidence of NRL allergy in personnel working in health care facilities insured by the German statutory accident insurance company for health care workers, Berufsgenossenschaft für Gesundheitsdienst und Wohlfahrtspflege, with approximately 3 million insured employees, by switching to powder-free NRL gloves. METHODS: The timing of introduction of intervention strategies, such as education of both physicians and administrators, together with regulations demanding that health care facilities only purchase low-protein, powder-free NRL gloves are reported. We reviewed the annual numbers of reported suspected cases of NRL-caused occupational allergies and the amount and type of gloves used in German acute-care hospitals since 1986. RESULTS: The purchase of powder-free NRL examination gloves exceeded that of powdered gloves for the first time in 1998. This only became true for powder-free NRL sterile gloves 2 years later in 2000. The incidence of suspected occupational NRL allergy cases rose until 1998 and has declined steadily since. There was a 2-year lag between the beginning of the decline in the purchase of powdered NRL examination gloves and the beginning of a decline in suspected NRL-caused occupational asthma cases. CONCLUSIONS: Despite the effect of increased recognition of NRL allergies, education about NRL allergies in health care facilities combined with the introduction of powder-free gloves with reduced protein levels has been associated with a decline in the number of suspected cases of occupational allergies caused by NRL in Germany on a nationwide scale. These results clearly indicate that primary prevention of occupational NRL allergies can be achieved if these straightforward and practical interventions are properly carried out and maintained.  相似文献   
34.
Mannitol salt agar was evaluated for detection of oxacillin resistance in 136 Staphylococcus aureus isolates. All mecA-positive isolates (n = 54) were correctly categorized as oxacillin resistant by the disk diffusion test (1-μg disk; zone diameter, <16 mm); the specificity was 97.6%. Agar screening (2 μg of oxacillin per ml) revealed a sensitivity of 98.1% and a specificity of 95.1%.  相似文献   
35.
Cyclin B3 has been conserved during higher eukaryote evolution as evidenced by its identification in chicken, nematodes, and insects. We demonstrate that Cyclin B3 is present in addition to Cyclins A and B in mitotically proliferating cells and not detectable in endoreduplicating tissues of Drosophila embryos. Cyclin B3 is coimmunoprecipitated with Cdk1(Cdc2) but not with Cdk2(Cdc2c). It is degraded abruptly during mitosis like Cyclins A and B. In contrast to these latter cyclins, which accumulate predominantly in the cytoplasm during interphase, Cyclin B3 is a nuclear protein. Genetic analyses indicate functional redundancies. Double and triple mutant analyses demonstrate that Cyclins A, B, and B3 cooperate to regulate mitosis, but surprisingly single mutants reveal that neither Cyclin B3 nor Cyclin B is required for mitosis. However, both are required for female fertility and Cyclin B also for male fertility.  相似文献   
36.
SV40 tumor antigen (T-Ag)-related antigens were detected serologically on the surface (surface T) of living SV40-transformed human and mouse monolayer cells by an 125I-protein A binding assay. In immunofluorescence analysis, these cells were negative for surface T. However, on mKSA, a SV40-transformed mouse cell line grown in suspension or on SV40-transformed human and mouse monolayer cells put into suspension, surface T could be visualized by immunofluorescence microscopy. The antisera used in these experiments were raised in rabbits with purified, SDS-denatured SV40 T-Ag or came from hamsters bearing SV40 tumors. Both types of antisera had in common high titers against SV40 T-Ag (?1:1000). All these antisera were negative on normal cells or on polyoma virus-transformed cells. The specificity of both antisera for SV40 T-Ag-related binding sites on the surface of SV40-transformed cells were demonstrated by an 125I-IgG blocking assay in which preincubation of the cells with rabbit anti-T-Ag serum inhibited the binding of hamster SV40 tumor serum to the cell surface by about 85%. These results demonstrate the expression of T-Ag-related antigens on the surface of living cells and, therefore, support the hypothesis that SV40 T-Ag-related antigens participate in the formation of the SV40-specific tumor transplantation antigen (TSTA).  相似文献   
37.
38.
Nine novel sugar transporter-like proteins have been discovered in the past 5 years. The mRNA for three of these, the glucose transporters (GLUT) GLUT8, GLUT11 and GLUT12, have been detected in human skeletal muscle. In the present study, we examined the pattern of expression and localization of the GLUT isoforms 8, 11 and 12 in human skeletal muscle using an immunohistochemical approach. Biopsies of human skeletal muscle from sedentary or trained healthy adults, from fetal muscle (24 weeks of gestation), from obese type-2 diabetic subjects, and from patients suffering from polymyositis or amyotrophic lateral sclerosis (ALS) were studied. GLUT8 and 12 immunoreactivity was below detection level in both developing and adult muscle fibres. GLUT11 immunoreactivity, however, was present in slow-twitch muscle fibres, but not in fast twitch fibres. Since, in contrast, GLUT4 was expressed in all investigated muscle fibres, the pattern of expression of GLUT11 differs from that of GLUT4, suggesting a specialized function for GLUT11 with a regulation independent from that of GLUT4. Obesity, type-2 diabetes, training, conditions of de- and reinnervation (ALS) and regeneration (polymyositis) failed to induce GLUT8 or -12 expression. Likewise, the fibre type-dependent pattern of GLUT11 immunoreactivity was unaltered. However, some slow muscle fibres lose their GLUT11 immunoreactivity under regeneration. Our results indicate that GLUT11 immunoreactivity, in contrast to that of GLUT4, is expressed exclusively in slow-twitch muscle fibres and is unaffected by physiological and pathophysiological conditions except in primary myopathy. GLUT8 and GLUT12 do not appear to be of importance in human muscle under physiological and pathophysiological conditions.  相似文献   
39.
Zusammenfassung Es wird über erste Ergebnisse einer Therapie der Hyperlipoproteidämie mit einer Retardpräparation des ß-Pyridyl-carbinol (Ronicol retard®) berichtet. Neben einer ausgeprägten Senkung der Gesamtesterfettsäuren und des Cholesterins im Serum wurde ein Rückgang der Leberepithelverfettung erreicht. Als Wirkungsmechanismus wird neben der bekannten Hemmung der Acylierung durch Nicotinsäure eine Hemmung der Fettmobilisierung (Hemmung einer adrenalinsensiblen Fettgewebslipase) diskutiert.Versuchspräparat der Firma Hoffman-La Roche AG; inzwischen als Ronicol-retard im Handel.  相似文献   
40.
Today the use of pneumatic tourniquet is commonly accepted in total knee arthroplasty (TKA) to reduce perioperative blood loss. There are a few prospective randomised and nonrandomised studies that compare the effect of tourniquet release timing in cementless or cemented unilateral TKA. However, many of these studies show an inadequate reporting and methodology. This randomized prospective study was designed to investigate the efficiency of tourniquet release timing in preventing perioperative blood loss in a simultaneous bilateral TKA study design. To our knowledge, this is the first study of its kind, in which the effect of tourniquet release timing on perioperative blood loss was investigated in simultaneous bilateral cemented TKA to compare both techniques intraindividually. In 20 patients (40 knees) one knee was operated with tourniquet release and hemostasis before wound closure, and the other knee with tourniquet release after wound closure and pressure dressing. We found no significant difference in total blood loss between both techniques (p=0.930), but a significant difference in operating time (p=0.035). There were no postoperative complications at a follow-up of 6 month. Other studies report an increase the blood loss in early tourniquet release and an increase the risk of early postoperative complications in deflation of tourniquet after wound closure. In this study we found no significant difference in perioperative blood loss and no increase of postoperative complications. Therefore, we recommend a tourniquet release after wound closure to reduce the duration of TKA procedure and to avoid possible risks of extended anaesthesia.  相似文献   
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