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111.
Book reviews     
Gábor Guti 《Hydrobiologia》1992,241(3):195-198
The numbers of perch Perca fluviatilis in the Cikola backwater system of the river Danube were estimated by mark-recapture techniques using multiple fishings. Fish were caught by fyke nets and electrical fishing. The latter method was unselective for sex and the catch data could be used to correct the sex bias in the fyke net catches. A population estimate in April of 6059 ind ha–1 (95% C.L. 5135–7386) for perch > 5 cm was obtained for a 0.6 ha area of backwater and 1665 ind ha–1 (95% C.L. 1204–2692) in May for a 0.4 ha area of a small bay.  相似文献   
112.
Administration of lithium chloride to rats injected intracerebrally with [3H]inositol led to time- and dose-dependent increases in levels of labeled inositol monophosphates in brain. Quantitative analysis of the inositol phosphates by ion chromatography revealed 37- and 20-fold increases in the mass of myo-inositol 1-phosphate and 4-phosphate, respectively, at 4 h intraperitoneal after injections of 6 mEq/kg of lithium chloride. Albeit to a much lesser extent, lithium administration also resulted in an increase in the level of myo-inositol, 1,4-bisphosphate in brain. The lithium-induced increase in content of labeled inositol monophosphates was marked by a concomitant decrease in content of labeled inositol, and after injections of high doses of lithium, e.g., 10 mEq/kg, this was followed by a general decrease in labeling of the inositol phospholipids. In general, animals injected with [3H]inositol but not lithium did not reveal obvious differences in labeling of inositol monophosphates on stimulation by mecamylamine or pilocarpine. However, when animals were injected with [3H]inositol and then lithium, there were large increases in the levels of labeled inositol monophosphates on administration of these compounds. Administration of atropine to the lithium-treated mice led to a partial reduction in the amount of labeled inositol monophosphates accumulated due to the administration of lithium alone. Furthermore, atropine was able to block the pilocarpine-induced increase in level of labeled inositol monophosphates. These results demonstrate the suitable use of the radiotracer technique together with lithium administration for assessing the effects of drugs and receptor agonists on the signaling system involving polyphosphoinositide turnover in brain.  相似文献   
113.
We have examined a serum-deprived culture system in order to verify that it is suitable for the study of burst forming unit erythroid (BFU-E) progenitor cells from premature neonates. Optimum growth of BFU-E from premature neonates was observed with each media constituent using the same concentration as that previously described for adult subjects. Growth of immature BFU-E from premature neonates were highly dependant upon a source of Burst Promoting Activity and mature BFU-E derived colonies emerged at day 12 compared to day 14 in adults. Our preliminary results with the validated medium suggest that premature infants have increased peripheral blood concentrations of BFU-E compared to healthy adult controls.Abbreviations Ad Adherent cells - BPA Burst promoting activity - BFU-E Burst forming unit erythroid - Epo Erythropoietin - IL3 Interleukin-3 - LDC Low density (<1.077 g ml1) peripheral blood mononuclear cells  相似文献   
114.
The courses of infection in inbred mouse strains were compared following infection with three Stabilates of high, intermediate, and low virulence of Trypanosoma vivax stock Zaria Y486. Mouse strains could only be shown to differ in their resistance to T. vivax infections as judged by the height of the initial parasitemia and survival times when a trypanosome population of low or intermediate virulence was used. A T. vivax population of high virulence was uniformly lethal. Comparison of lytic antibody titers between groups of resistant (C57B16) and susceptible (Balbc) mice did not show any significant differences in titers of the surviving mice but the mice in either group which did not control the initial parasitemia had lower lytic antibody titers than those which did. A significantly larger number of Balbc mice failed to control the initial infection as compared to the C57B16. Treatment with cyclophosphamide did not ablate differences in susceptibility between the two strains. The use of congenic mice showed that these differences in susceptibility were not related to differences in the major histocompatibility complex between these strains.  相似文献   
115.
In a comparative study the requirement of several strains of autotrophic hydrogen-oxidizing bacteria for nickel was examined. Autotrophic growth was studied both in liquid media, previously freed from trace metals; and on solidified media, using a plate diffusion assay. The latter assay was based on the observation that EDTA causes complete inhibition of autotrophic growth on agar medium as a result of nickel deficiency. Nickel was shown to be required as a trace element in five strains of Alcaligenes eutrophus, in two strains of Xanthobacter autotrophicus, in Pseudomonas flava, in Arthrobacter spec. 11X and in strain 12X. In these bacteria nickel was not replaceable by cobalt, copper, manganese or zinc ions. No significant nickel requirement was detected by these methods, however, for Paracoccus denitrificans and Nocardia opaca 1b.  相似文献   
116.
Bile and serum samples were collected from calves with an implanted cannula throughout a 20-week period of infection with Fasciola hepatica. Using indirect fluorescent antibody labelling and plastic-embedded sections of juvenile and adult flukes as antigens, estimates were made of the relative concentrations of IgG and IgA specific for fluke tegumental and gut antigens in the samples of serum and bile. In serum, antibodies against juvenile (t1) tegument and gut antigens reached peak concentrations 4–6 weeks postinfection and declined slowly thereafter as flukes became established in the bile ducts. IgG against adult tegument (t2) antigens appeared in the serum 6 weeks after infection, but no IgA against t2 was detected. In the bile, both IgG and IgA titres against t1 and gut antigens rose to peak values at 4–6 weeks after infection, but there was no activity against t2 antigen. The Ig levels in bile were considerably lower than in serum. Much more IgA relative to IgG occurred in bile as compared to serum (IgG/IgA ratio in serum was 16–32, in bile 1–2) suggesting a role for IgA in defence at mucosal surfaces. Comparison of the antibody profiles in bile and serum suggested that IgG in the bile was derived from circulating IgG whereas IgA may have been preferentially concentrated in the bile.  相似文献   
117.
The glucosephosphate isomerase (GPI) zymogram phenotypes of 46 aneuploid derivatives of the cultivar Chinese Spring of hexaploid wheat were determined. Variation was observed among the strains in the relative level of expression of three GPI isozymes. The relationships observed between chromosomal constitution and zymogram phenotype support the hypothesis that the three GPI isozymes are dimers composed of protomers encoded by a minimum of three homoeologous structural genes located one each in the short arms of chromosomes 1A, 1B, and 1D. The relative levels of expression per dose of chromosome arm of the products of the three arms differ in a manner consistent with the presence of a two-fold greater quantity of the product of 1BS than of the product of 1AS and of 1DS, indicating that 1BS may contain duplicate GPI structural genes.  相似文献   
118.
Innominate bones from 362 California Indians were sexed with Phenice's three non-metrical features of the os pubis. The frequencies of marked, intermediate, and absent cases of these three morphological features were tabulated in males and females to see if unambiguous and reliable distinctions were consistently available. The results suggest that Phenice's technique offered extremely reliable sex evaluations in this material.  相似文献   
119.
《Cell》2022,185(18):3375-3389.e21
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120.
Assessing the agreement between two or more raters is an important topic in medical practice. Existing techniques, which deal with categorical data, are based on contingency tables. This is often an obstacle in practice as we have to wait for a long time to collect the appropriate sample size of subjects to construct the contingency table. In this paper, we introduce a nonparametric sequential test for assessing agreement, which can be applied as data accrues, does not require a contingency table, facilitating a rapid assessment of the agreement. The proposed test is based on the cumulative sum of the number of disagreements between the two raters and a suitable statistic representing the waiting time until the cumulative sum exceeds a predefined threshold. We treat the cases of testing two raters' agreement with respect to one or more characteristics and using two or more classification categories, the case where the two raters extremely disagree, and finally the case of testing more than two raters' agreement. The numerical investigation shows that the proposed test has excellent performance. Compared to the existing methods, the proposed method appears to require significantly smaller sample size with equivalent power. Moreover, the proposed method is easily generalizable and brings the problem of assessing the agreement between two or more raters and one or more characteristics under a unified framework, thus providing an easy to use tool to medical practitioners.  相似文献   
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