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1.
2.
Dieter Ehlers Ina Sakowski Werher Mohrig 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1989,159(4):481-489
Summary The high affinity of granulocytes of guinea pig and man to glass surfaces is modified by serum. Native serum contains both an adherence-promoting activity, which is related to complement, and components which reduce the adhesiveness of granulocytes. These components are stable at 56°C for 30 min and are tightly bound to the glass surface. -Lipoproteins are candidates for this adherence reducing ability of serum. Adherence promotion by native serum is mediated by coating the glass surface with C3b/C3bi. Human granulocytes from the peripheral blood adhered to glass surfaces coated by native human or guinea pig serum with C3b/C3bi to almost the same extent as in the presence of native serum, but on guinea pig granulocytes elicited in the peritoneal cavity, a cell surface metalloproteinase degraded the C3b/C3bi, thus reducing the adhesiveness of these cells. This proteinase was inhibited by MgEDTA, DTT, and 1,10-phenanthroline, whereby the high adhesiveness of granulocytes was restored to C3b/C3bi-coated glass.Abbreviations
BA
benzamidine hydrochloride
-
BTS
Bacillus thuringiensis subtoxicus
-
DTT
dithiothreitol
-
EAC
-amino-caproic acid
-
gp
guinea pig
-
LDL
low density lipoproteins
-
SEM
scanning electron microscopy 相似文献
3.
Jessica E. Hoogendijk Gerard W. Hensels Ina Zorn Linda Valentijn Emiel A. M. Janssen Marianne de Visser David F. Barker Bram W. Ongerboer de Visser Frank Baas Pieter A. Bolhuis 《Human genetics》1991,88(2):215-218
Summary Recently, it has been shown that Charcot-Marie-Tooth disease type 1a (CMT1a) is linked with a duplication of a DNA segment that is detected by probe VAW409R3, and that is located on chromosome 17p11.2. Here, we show that this duplication also contains VAW412R3a, but not A10-41 and EW503. Accounting for the duplication in recombination analysis, we found recombinants between CMT1a and EW301 and EW502, but not with A10-41, VAW409R3, and VAW412R3. Using pulsed-field gel electrophoresis analysis, we estimated the minimal size of the duplicated region in CMT1a patients to be 1100 kb. 相似文献
4.
Summary DNA haplotype constellations of the β-globin gene cluster have been analyzed in German families with hemoglobinopathies (Hb
Freiburg, Hb K?ln, Hb Presbyterian) and β-thalassemias. The polymorphis patterns obtained were compared to those found in
families from Greece, Italy, and Turkey affected by β-thalassemia syndromes. With the combined analysis of seven restriction
site polymorphisms a DNA-diagnostic prediction for additional offspring could be made with an overall frequency of 75% in
the four ethnic groups. 相似文献
5.
The effects of intraperitoneally or intracerebrally (DA A-10 area) administered substance P (SP) on locomotor activity of rats were studied in an exact 12-h light/12-h dark cycle changing from dark to light at 6 a.m. SP was administered either at 11 a.m. (light phase, minimal locomotor activity) or at 7 p.m. (dark phase, maximal locomotor activity). The effects of 12.5 micrograms/kg SP intracerebral and 125 micrograms/kg SP intraperitoneal were very similar. In the light phase SP produces excitation but inhibition of locomotion in darkness. Hence, the effect of SP depends on the internal mechanisms controlling motor activity and tends to level off the spontaneous circadian oscillation. We found a long lasting SP effect during both the light and dark period. The present experiments led us to the conclusion that SP has a levelling effect on locomotor activity. Probably this effect might be explained as SP's action on the dopaminergic pathway or dopamine metabolism, because the dopamine content in neurons also has a circadian rhythm. 相似文献
6.
Scavenging of Hydrogen Peroxide in the Endosperm of Ricinus communis by Ascorbate Peroxidase 总被引:6,自引:0,他引:6
The fat-storing endosperm of Ricinus communis L. was found tocontain an ascorbate peroxidase (EC 1.11.1.11
[EC]
), which is nearlyas active as catalase (EC 1.11.1.6
[EC]
) in degradation of hydrogenperoxide (H2O2) at its physiological concentrations. This ascorbateperoxidase probably functions together with monodehydroascorbatereductase (EC 1.6.5.4
[EC]
) or dehydroascorbate reductase (EC 1.8.5.1
[EC]
)and glutathione reductase (EC 1.6.4.2
[EC]
) to remove the H2O2 producedduring the transformation of fat to carbohydrate in the glyoxysomes.The activities of these enzymes as well as the content of ascorbateand glutathione increase parallel to the activities of glyoxysomalmarker enzymes during the course of germination. Inhibitionof catalase by aminotriazole results in increases of the ascorbateperoxidase activity and of the glutathione content. All fourenzymes are predominantly localized in the cytosol of the Ricinusendosperm with low activities found in the plastids and themitochondria. The results suggest, that the ascorbate-dependentH2O2 scavenging pathway, which has been shown to be responsiblefor the reduction of photosynthetically derived H2O2 in thechloroplasts, operates also in the Ricinus endosperm. (Received June 5, 1990; Accepted July 31, 1990) 相似文献
7.
8.
The 3-end of the cDNA encoding the smg GDP dissociation stimulator (smg GDS) protein shares 100% homology with the previously published expressed sequence tag 00038 site. This site extends the 3-end of the smg GDS gene by 212 bp. It has been localized to human chromosome 4. Here, we have refined the localization of smg GDP to human chromosome 4q21-q25 using a mapping panel of rodent/human somatic cell hybrids containing different parts of chromosome 4. This chromosomal localization of smg GDP to 4q21-25 overlaps with a region of allele loss in primary hepatocellular carcinoma (4q13-q26).HGM symbol: RAP1GDS1 相似文献
9.
Hans Oehme 《Journal of Ornithology》1959,100(4):363-396
Zusammenfassung Die aerodynamischen Verhältnisse des Schwingenfluges bei verschiedenen Kleinvögeln werden beschrieben. Es wird der unbeschleunigte Horizontalflug bei Mauersegler, Rauchschwalbe und rundflügeligen kleinen Sperlingsvögeln verglichen. Als Kenngrößen des Kraftfluges werden der Fortschrittsgrad, das Verhältnis Hub/Schub an der Flügelspitze (A/V) und das Gesamtauftriebs-Vortriebs-Verhältnis (Ages/V) abgeleitet. An Hand dieser Kenngrößen wird gezeigt, daß es möglich ist, einen Hubflug von einem Schubflug zu unterscheiden. Diese Unterscheidung ist weder an eine bestimmte Art der Flügelbewegung gebunden, noch charakterisiert sie als alleinige Flugweise eine bestimmte Vogelart. Die Besonderheiten des Schnellfluges und des Fluges auf der Stelle bei den untersuchten Arten werden dargestellt, wobei der Unterschied zwischen Platzrüttelflug und Platztrillerflug betont wird.Es wird gezeigt, daß die Flugeigenschaften der besprochenen Arten von ihrer Lebensweise her, besonders von der Art des Nahrungserwerbs verstanden werden können.Der Zusammenhang zwischen Flugweise und Bau des Flügels wird an einigen Beispielen erörtert. Dabei können Beziehungen zwischen den aerodynamischen Eigenschaften des Flügels und dem Bau der Federn bis hin zu deren Feinstrukturen gezeigt werden. Skelett und Muskulatur lassen zwar auch gewisse funktionell bedingte Eigenarten erkennen, doch sind eindeutige Beziehungen manchmal nicht herzustellen.Es zeigt sich, daß es möglich ist, bestimmte Struktureigenschaften aus ihrer Funktion zu begreifen, daß aber die Herleitung bestimmter Flugmodi aus Strukturmerkmalen des Flügels oft große Schwierigkeiten bereitet, und daß es hier als unmöglich angesehen werden muß, von einigen morphologischen Eigenschaften ausgehend zu richtigen Schlüssen zu kommen. 相似文献
10.
New methods for estimating the numbers of synonymous and nonsynonymous substitutions 总被引:10,自引:0,他引:10
Yasuo Ina 《Journal of molecular evolution》1995,40(2):190-226
New methods for estimating the numbers of synonymous and nonsynonymous substitutions per site were developed. The methods are unweighted pathway methods based on Kimura's two-parameter model. Computer simulations were conducted to evaluate the accuracies of the new methods, Nei and Gojobori's (NG) method, Miyata and Yasunaga's (MY) method, Li, Wu, and Luo's (LWL) method, and Pamilo, Bianchi, and Li's (PBL) method. The following results were obtained: (1) The NG, MY, and LWL methods give overestimates of the number of synonymous substitutions and underestimates of the number of nonsynonymous substitutions. The major cause for the biased estimation is that these three methods underestimate the number of synonymous sites and overestimate the number of nonsynonymous sites. (2) The PBL method gives better estimates of the numbers of synonymous and nonsynonymous substitutions than those obtained by the NG, MY, and LWL methods. (3) The new methods also give better estimates of the numbers of synonymous and nonsynonymous substitutions than those obtained by the NG, MY, and LWL methods. In addition, estimates of the numbers of synonymous and nonsynonymous sites obtained by the new methods are reasonably accurate. (4) In some cases, the new methods and the PBL method give biased estimates of substitution numbers. However, from the number of nucleotide substitutions at the third position of codons, we can examine whether estimates obtained by the new methods are good or not, whereas we cannot make an examination of estimates obtained by the PBL method. (5) When there are strong transition/transversion and nucleotide-frequency biases like mitochondrial genes, all of the above methods give biased estimates of substitution numbers. In such cases, Kondo et al.'s method is recommended to be used for estimating the number of synonymous substitutions, although their method cannot estimate the number of nonsynonymous substitutions and is time-consuming. These results, particularly result (1), call for reexaminations of some genes. This is because evolutionary pictures of genes have often been discussed on the basis of results obtained by the NG, MY, and LWL methods, which are favorable for the neutral theory of molecular evolution. 相似文献