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91.
The immune system is one of the most important adaptations that has evolved to protect animals from a wide range of pathogens they encounter from early life onwards. During the early developmental period this is particularly true for the innate immunity, as other components of the immune system are, as yet, poorly developed. But innate immunity may not only be crucial for early life survival, but may also have long‐lasting effects, for example if early life immunity reflects the functioning of the immune system as a whole. For this reason, we investigated the importance of four constitutive innate immune parameters (natural antibodies, complement activity, concentrations of haptoglobin, and concentrations of nitric oxide) for recruitment in free‐living great tits. We compared nestling immunity of recruits with nestling immunity of their nonrecruited siblings. We also investigated within individual consistency of these innate immune parameters for those individuals that recruited, which may be taken as a measure of immune capacity. In accordance with previous studies, we found a clear effect of tarsus length and a trend for body mass on the likelihood to recruit. Nevertheless, we found no evidence that higher levels of constitutive innate immunity as a nestling facilitated local recruitment. Furthermore, individual innate immunity was not consistent across life stages, that is to say, nestling immune parameters did not determine, or respectively, reflect adult innate immune parameters. This plasticity in innate immune components may explain why we did not find long‐lasting survival benefits. 相似文献
92.
In order to examine a possible role of calcium in graviperception, the calcium ionophore A23187 was used to elevate the concentration of free cytoplasmic calcium in statocytes of the roots of Lepidium sativum L. After a brief incubation (30 min) in a medium that contained 10 micromoles A23187 and 5.5 micromoles CaCl2, 50% of the roots bent gravitropically during a subsequent 2 h of horizontal exposure, with an angle of curvature that varied from 5 degrees to 70 degrees. The corresponding statocytes exhibited a polar arrangement of cell organelles as did the controls. However, in statocytes from 50% of the roots which were not curved after gravistimulation a portion of the distal endoplasmic reticulum (ER) complex was displaced in the direction of gravity within 30 min of horizontal exposure. After washing of the briefly treated roots for 24 h with 1% dimethylsulfoxide the percentage of gravitropically bending roots increased to approximately 80%, but the angle of curvature amounted to only 5 degrees-10 degrees. Longer treatment (2 h) with A23187 caused a complete loss of graviresponsiveness which was accompanied by disintegration of statocyte polarity. We concluded from these results that i) calcium is involved in graviperception and ii) gravisensitivity depends on the integrity of statocytes. 相似文献
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96.
The current Association of Official Analytical Chemists method for testing tuberculocidal activity of disinfectants has been shown to be inaccurate and to have a high degree of variability. An alternate test method is proposed which is more accurate, more precise, and quantitative. A suspension of Mycobacterium bovis BCG was exposed to a variety of disinfectant chemicals and a kill curve was constructed from quantitative data. Data are presented that show the discrepancy between current claims, determined by the Association of Official Analytical Chemists method, of selected commercially available products and claims generated by the proposed method. The effects of different recovery media were examined. The data indicated that Mycobacteria 7H11 and Middlebrook 7H10 agars were equal in recovery of the different chemically treated cells, with Lowenstein-Jensen agar having approximately the same recovery rate but requiring incubation for up to 3 weeks longer for countability. The kill curves generated for several different chemicals were reproducible, as indicated by the standard deviations of the slopes and intercepts of the linear regression curves. 相似文献
97.
Summary The investigation of 107 families with at least 2 children gives no evidence for genetic linkage between the structural loci for ABO and Gc. 相似文献
98.
Summary The frequency of heterozygotes for the glutathione-reductase in a sample of 215 young healthy Germans is 1,9%. Suggesting a 2-allele-model we can calculate the frequency of the three phenotypes in the population: GR(A)=98,1%, GR(AB)=1,9%, GR(B)=0,009%. No correlation between blood-and serum-groups and the enzyme activity could be found.
Direktor: Prof. Dr. med. G. W. Löhr
Direktor: Prof. Dr. med. G. G. Wendt
Mit dankenswerter Unterstützung durch die Deutsche Volkswagen-Stiftung. Herrn Professor Dr. H. E. Bock, Tübingen, zum 65. Geburtstag gewidmet. Wesentliche Teile dieser Arbeit werden von Andreas v. Lingen der Medizinischen Fakultät Marburg als Dissertation vorgelegt. 相似文献
Direktor: Prof. Dr. med. G. W. Löhr
Direktor: Prof. Dr. med. G. G. Wendt
Mit dankenswerter Unterstützung durch die Deutsche Volkswagen-Stiftung. Herrn Professor Dr. H. E. Bock, Tübingen, zum 65. Geburtstag gewidmet. Wesentliche Teile dieser Arbeit werden von Andreas v. Lingen der Medizinischen Fakultät Marburg als Dissertation vorgelegt. 相似文献
99.
Zusammenfassung Mit Hilfe der Stärkegelelektrophorese wurden die phänotypischen Variationen der alkalischen Serumphosphatase bei 746 Gesunden, 62 Patienten mit Ulcus duodeni, 95 Patienten mit Ulcus ventriculi und 65 Patienten mit Magencarcinom untersucht. Die Beziehungen der quantitativen Variationen der langsamer wandernden B-Komponente zum ABO-Blutgruppensystem, zum Lewis-Blutgruppensystem, zum ABH-Ausscheidersystem und ihre Abhängigkeit von der Nahrungszufuhr werden bestätigt.Bei der Untersuchung von 637 nicht nüchternen Gesunden wurde eine positive Korrelation der B-Bande zu den Blutgruppen O, B und Le(a-/b+) und den Ausscheidern von ABH-Substanzen gefunden. Eine negative Korrelation der B-Bande fand sich zu den Blutgruppen A1, Le(a+/b-) und den Nichtausscheidern von ABH-Substanzen.Bei einem Vergleichskollektiv von 109 nüchternen Gesunden wurde im Prinzip wieder die gleiche Korrelation gefunden. Die Häufigkeit und auch die Intensität der B-Bande war jedoch insgesamt geringer als bei den nicht nüchternen Gesunden.Nach Nahrungsaufnahme kommt es zu einem Anstieg der Intensität der B-Komponente der alkalischen Phosphatase im Serum, wie in einem Diätversuch bei drei Personen gezeigt werden konnte.Bei Patienten mit Ulcus duodeni, Ulcus ventriculi und Carcinoma ventriculi war sowohl die Häufigkeit als auch die Intensität der B-Bande geringer als bei Gesunden. Diese Abweichung wird auf eine Änderung der Ernährungsweise oder eine Störung im Bereich des Gastrointestinaltraktes zurückgeführt. Für einen Zusammenhang zwischen der B-Komponente der alkalischen Serumphosphatase und der bekannten ABO-Blutgruppenassoziation der drei untersuchten gastrointestinalen Erkrankungen ergab sich kein eindeutiger Hinweis.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft, Bad Godesberg. 相似文献
The alkaline serum phosphatase has been studied by starch gel electrophoresis in 746 healthy individuals, 62 patients with duodenal ulcer, 95 patients with stomach ulcer, and 65 patients with stomach cancer (Fig. 1, Table 1). The previously reported quantitative variations of the B-component of alkaline phosphatase, which is presumably identical with the intestinal component, has been confirmed. The variations of the B-component are associated with the ABO blood group system, the Lewis blood group system, and the ABH secretor status; they are also influenced by diet.In a sample of 637 healthy, nonfasting persons the B-component was positively correlated to the O, B and Le(a-/b+) blood groups and to ABH secretion. The B-component was negatively associated with the A1 and Le(a+/b-) blood groups and the ABH non-secretor status (Table 2 and 3).In a sample of 109 fasting healthy individuals the B-component was less frequent and also less intense if present. Nevertheless, the same correlations to the ABO and Lewis blood groups and the ABH secretor status are found as in the non-fasting control (Table 5 and 6).In three persons the increase of the B-component of alkaline phosphatase in serum was followed after intake of a fatty meal (Table 7, Fig. 2 and 3).In patients with duodenal ulcer, stomach ulcer and stomach cancer the B-component is less frequent and less intense than in the control group of fasting healthy individuals. This deviation is related to differences in the diet or to disturbances of the gastrointestinal functions in these patients. There was no clear indication of a connection between the B-component of alkaline phosphatase and the ABO blood groups association with these gastrointestinal diseases (Table 8, 9, and 10).
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft, Bad Godesberg. 相似文献
100.