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51.
Notfall + Rettungsmedizin - Der Europäische Rat für Wiederbelebung hat diese Leitlinie – Basismaßnahmen zur Wiederbelebung – auf Grundlage des...  相似文献   
52.
Journal of Public Health - Neighbourhood composition is considered a social determinant of mental health that can be addressed by policymakers to improve outcomes. Deprived neighbourhoods typically...  相似文献   
53.
T follicular helper (TFH) cells play an essential role in promoting B cell responses and antibody affinity maturation in germinal centers (GC). A subset of memory CD4+ T cells expressing the chemokine receptor CXCR5 has been described in human blood as phenotypically and clonally related to GC TFH cells. However, the antigen specificity and relationship of these circulating TFH (cTFH) cells with other memory CD4+ T cells remain poorly defined. Combining antigenic stimulation and T cell receptor (TCR) Vβ sequencing, we found T cells specific to tetanus toxoid (TT), influenza vaccine (Flu), or Candida albicans (C.alb) in both cTFH and non-cTFH subsets, although with different frequencies and effector functions. Interestingly, cTFH and non-cTFH cells specific for C.alb or TT had a largely overlapping TCR Vβ repertoire while the repertoire of Flu-specific cTFH and non-cTFH cells was distinct. Furthermore, Flu-specific but not C.alb-specific PD-1+ cTFH cells had a “GC TFH-like” phenotype, with overexpression of IL21, CXCL13, and BCL6. Longitudinal analysis of serial blood donations showed that Flu-specific cTFH and non-cTFH cells persisted as stable repertoires for years. Collectively, our study provides insights on the relationship of cTFH with non-cTFH cells and on the heterogeneity and persistence of antigen-specific human cTFH cells.  相似文献   
54.
55.
The ability of some N,N-dialkylaminosubstituted chromones and isoxazoles to inhibit the protein kinase C (PKC) dependent signal transduction pathway was tested. As a cellular model, human neutrophils stimulated with either phorbol myristate acetate (PMA) or formylmethionine-leucine-phenylalanine (f-MLF) were used. The efficiency of the compounds was established by their capacity to reduce the O2- production by activated human neutrophils. Compounds carrying a 3-bis(2-methoxyethyl)amino group, a substituent found active in previously tested tricyclic compounds, do not show significant anti-PKC activity in this study. On the other hand, substitution with a 1-piperidinyl group leads all tested compounds to a high biological activity against stimulated neutrophils.  相似文献   
56.
Summary A rat model was used to evaluate the general acute toxicity and the late cardiotoxicity of 4 mg/kg doxorubicin (DOX) given either as free drug or in the form of threeN-(2-hydroxypropyl)methacrylamide (HPMA) copolymer conjugates. In these HPMA copolymers, DOX was covalently bound via peptide linkages that were either non-biodegradable (Gly-Gly) or degradable by lysosomal proteinases (Gly-Phe-Leu-Gly). In addition, one biodegradable conjugate containing galactosamine was used; this residue was targeted to the liver. Over the first 3 weeks after the i.v. administration of free and polymer-bound DOX, all animals showed a transient reduction in body weight. However, the maximal reduction in body weight seen in animals that received polymer-bound DOX (4 mg/kg) was significantly lower than that observed in those that received free DOX (4 mg/kg) or a mixture of the unmodified parent HPMA copolymer and free DOX (4 mg/kg;P<0.01). Throughout the study (20 weeks), deaths related to cardiotoxicity were observed only in animals that received either free DOX or the mixture of HPMA copolymer and free DOX; in these cases, histological investigations revealed marked changes in the heart that were consistent with DOX-induced cardiotoxicity. Sequential measurements of cardiac output in surviving animals that received either free DOX or the mixture of HPMA copolymer and free DOX showed a reduction of 30% in function beginning at the 4th week after drug administration. The heart rate in these animals was 12% lower than that measured in age-matched control rats (P<0.05). Animals that were given the HPMA copolymer conjugates containing DOX exhibited no significant change in cardiac output throughout the study (P<0.05). In addition, no significant histological change was observed in the hearts of animals that received DOX in the form of HPMA copolymer conjugates and were killed at the end of the study. However, these animals had shown a significant increase in heart rate beginning at 8 weeks after drug administration (P<0.01). This study demonstrates that covalent binding of DOX to HPMA copolymer conjugates via both stable and biodegradable peptidyl linkages considerably reduces both the general acute toxicity and the late cardiotoxicity of DOX in the rat and could offer the potential for improving the therapeutic index in the clinical application of DOX.  相似文献   
57.
Osteoporosis is a common finding in Turner's syndrome. To test the hypothesis that calcitonin deficiency may contribute to bone mineral loss in Turner's syndrome, we studied basal and calcium-stimulated (2 mg/kg body weight in 5 min) levels of total calcitonin, extractable calcitonin and katacalcin in 15 girls with Turner's syndrome and osteoporosis. Fifteen age-matched healthy girls were studied as controls. Both basal calcitonin (total and extractable) and katacalcin values were not significantly different in patients with Turner's syndrome in comparison with those of the controls. The calcium stimulation test showed a similar "C" cell secretory reserve in both groups. The calculation of delta CT/delta iCa of total and extractable calcitonin and delta KC/delta iCa, which accounts for individual variations in serum ionized calcium increases, did not show any significant difference between girls with Turner's syndrome and controls. We conclude that calcitonin deficiency is not a causative factor of osteoporosis in girls with Turner's syndrome and that in this syndrome long-life estrogen deficiency does not impair "C" cell secretory activity.  相似文献   
58.
Summary Neurological complications following rubella are only rarely encountered. However, in many cases severe neurological impairment may occur, leading to permanent disability. In a recent epidemic of rubella in Israel during the years 1978–1979, 20 patients with severe neurological complications have been seen. We report on 5 cases of which 3 are described in detail. Considering the efficacy of immunization against rubella, we suggest that in countries such as England and Israel in which periodic epidemics of rubella occur, a generalized plan of immunization should be undertaken during the first years of life. Such an approach will prevent the neurological complication of congenital, as well as acquired, rubella infection.
Zusammenfassung Obwohl neurologische Komplikationen nur selten nach Rubella erscheinen, sind sie in vielen Fällen schwer und können zu permanenten neurologischen Schäden führen. In einer Rubella-Epidemie, die kürzlich in Israel auftrat (1978–1979), wurden 20 Fälle von schweren neurologischen Komplikationen festgestellt. Wir berichten über 5 dieser Fälle, 3 von ihnen in ausführlicher Weise. Nachdem Rubella-Impfung sehr wirksam ist, schlagen wir vor, daß in Ländern wie Israel oder England, in denen Epidemien von Zeit zu Zeit auftreten, ein allgemeiner Impfungsplan für die ersten Lebensjahre eingeführt wird. So ein Plan kann die neurologischen Komplikationen nach kongenitaler oder erworbener Rubella verhindern.
  相似文献   
59.
A healthy 9 year old girl presented with severe posterior knee pain and a small segmental non-occlusive popliteal venous thrombosis. The case is relevant for its unique presentation and symptoms. Lack of recanalisation persisted at one year follow up.  相似文献   
60.
The Authors compare the results obtained between two groups of patients suffering from leg lipodystrophy, who were subjected to a reducing lipoplasty. In the first group, surgeons made use of a new sort of cannula, deprived of the classical grip, whereas in the second group, they employed the traditional probe. The best results, achieved with the first group, prove this new operating system is really effective, particularly on legs, for the following reasons: (1) Higher precision and better control of the instrument (2) Swan-neck cannula abolition (3) Opportunity to operate with both hands (4) Halved operating time (5) No tiredness after the operation.  相似文献   
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