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The inbred mouse strain DDD was found to have an extremely high incidence of hydronephrosis (37/37 in adult males and 12/32 in adult females). The hydronephrosis was classified as open with no definite cause for obstruction. The condition was either unilateral in the right kidney or bilateral. Another feature of the hydronephrotic kidney was circulatory failure. Hydronephrosis in strain DDD mice is considered to be a useful experimental animal model with additional possible use, in investigating disturbances of renal haemodynamics and function.  相似文献   

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Summary Anaerobic conditions obtained by flooding the soil caused reductive dechlorination of p,p-DDT and its conversion to p,p-DDD was enhanced under water-logged conditions creating or favouring anaerobiosis. The DDT showed recalcitrance in the soil kept at 15% moisture.More o,p-DDT was lost from the flooded soil. Similar amounts of p,p-DDE were detected in all of the three levels of technical DDT treatments and the concentrations were not significantly different under both aerobic and anaerobic conditions.  相似文献   

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Zusammenfassung An 17 Stämmen der Gattung Pediococcus, die auf Grund charakteristischer physiologisch-biochemischer Merkmale aus einer Anzahl von etwa 500 Kulturen unterschiedlicher Herkunft ausgewählt wurden, werden mit Hilfe der DNS/DNS-Hybridisierung die verwandtschaftlichen Beziehungen untersucht. Dabei wird die Eigenständigeit der Arten P. pentosaceus, P. acidilactici, P. parvulus, P. damnosus und P. halophilus bestätigt. Der für P. acidilactici vorgeschlagene Neotyp-Stamm NCDO 1859 ist jedoch nach den vorliegenden Ergebnissen ein echter P. pentosaceus. Ein Stamm von P. dextrinicus, der früher bereits als P. cerevisiae var. dextrinicus beschrieben wurde, zeigt zu keiner untersuchten Art eine genetische Verwandtschaft auf der Basis der DNS/DNS-Homologie. Zwei aus Bier und Bierhefe isolierte Stämme, die hinsichtlich des Phänotyps P. parvulus nahestehen, zeigen weder zu dieser Art noch zu allen anderen bisher beschriebenen Arten hinsichtlich des Genotyps einen hohen Verwandtschaftsgrad.
DNA-DNA homology studies on the genus Pediococcus
17 strains of Pediococcus, including new isolates and strains from various collections, were investigated by nucleic acid hybridisation. Most of the newly isolated strains, selected from about 500 strains according to physiological and biochemical characters, could be attributed to known species. The reassociation data demonstrate the separate status of P. pentosaceus, P. acidilactici, P. damnosus, P. parvulus and P. halophilus. The proposed neotype strain of P. acidilactici NCDO 1859, however, has been found to be in reality a genuine P. pentosaceus. P. dextrinicus, formerly described as P. cerevisiae var. dextrinicus showed a remarkable lack of relationship to any of the strains tested. Two isolates exhibiting a high phenotypic similarity to P. parvulus show little genetic relationship to this and especially to all other species.

Abkürzungen CTAB N-cetyl-N,N,N-trimethyammoniumbromid - EDTA Äthylendiamintetraessigsäure - PPO 2,5-Diphenyloxazol - POPOP 1,4-Bis-(5-phenyl-2-oxazolyl)-benzol - SSC Saline-Trinatriumcitrat (0,15M NaCl, 0,015M Trinatriumcitrat, pH 7,0) - Tris Tris(hydroxymethyl)-aminomethan - T m mittlere Schmelztemperatur der DNS Adresse für Sonderdruck-Anforderungen  相似文献   

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The mode of inheritance of hydronephrosis was investigated by crossing inbred DDD mice having a high incidence of hydronephrosis and C57BL/6 mice having normal kidneys. In the males, incidences of hydronephrosis in F1 animals were intermediate between the two parental strains at a rate of 32.6% in (DDD x C57BL/6)F1 and 23.4% in reciprocal F1. The same tendency was observed in F2 male animals. In BCF1 males, the number of affected mice was higher in (C57BL/6 x DDD) F1 x DDD (72.4%) than in (DDD x C57BL/6)F1 x C57BL/6 (11.1%). A few affected mice were found among the females of hybrids F1, F2 and BCF1. These results suggested that hydronephrosis in the DDD strain of mice was controlled by polygenes, and that male hormones may have some effect on the occurrence of hydronephrosis.  相似文献   

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To elucidate the possible participation of the Mtv-2 gene in the background factors relevant to mammary tumorigenesis, DDD/1-Miv-2/Mtv-2 (DDD-Mtv-2) congenic and DDD/1 background mice were compared for endocrine and immune organs, mammary gland development, expression of mouse mammary tumor virus (MMTV)-gp 52 antigen, hyperplastic alveolar nodules (HAN) and mammary tumor incidence. The congenic strain had been established by introducing Mtv-2 from GRS/AJms (GR) into DDD/1 mice by repeated 12 backcrosses. Body, thymus, spleen, uterus, ovary, adrenal and pituitary weights, histology of the ovary and mammary gland development showed no differences ascribable to Mtv-2 between both strains of mice at 4,6 and 12 months of age. In contrast, MMTV-gp 52 antigen expression, HAN and mammary tumor occurred in DDD-Mtv-2 but not in DDD/1 mice. These results showed that the Mtv-2 gene stimulates mammary tumorigenesis by constitutional production of endogenous MMTV which transforms mammary epithelial cells but not by influencing the background factors relevant to mammary tumorigenesis. Furthermore, the expression of Mtv-2 appeared to be lower on the DDD/1 than on the GR background.  相似文献   

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We found a female cataractous DDD/1-nu/+ mouse and established a hairy mutant strain (DDD/1-Cti/Cti) with 100% incidence of cataract from it by repeating sibmating. Genetic studies demonstrated that a single autosomal semidominant gene controls cataractogenesis. This gene was named Cti. In homozygotes, DDD/1-Cti/Cti, the lenses began to opacify at 14 days of fetal life and were recognized clinically as cataract at 13-14 days of age when the eyes first open. The opacification became more and more intense with age and looked like mature cataract at 28-42 days of age. However, clarification of the opacified lenses commenced at the periphery after 56 days of age and expanded to the inside with time, and only an opaque spot was left at the center at 140 days of age. In heterozygotes, DDD/1-Cti/+, the lenses were recognizable as cataract after 28 days and became like mature cataract around 35 days of age. The opacity began to be lightened at 42 days and the lenses appeared normal at 56 days of age. Both lenses and eyeballs developed in similar courses in DDD/1(-)+/+, -Cti/+ and -Cti/Cti, although slightly retarded in the last. Microphthalmia was not accompanied even in DDD/1-Cti/Cti. The lens water content remained higher during the time when intense lens opacity continued in DDD/1-Cti/Cti and -Cti/+. Background genes appeared to affect the expression of Cti. DDD/1-Cti(-)+ mice may provide a model for researches into clarification of opaque lenses. A discussion concerning the possible allelism of Cti and Cts with Lop was made based on their phenotypic characteristics.  相似文献   

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While a variety of statistical models now exist for the spatio-temporal analysis of two-dimensional (surface) data collected over time, there are few published examples of analogous models for the spatial analysis of data taken over four dimensions: latitude, longitude, height or depth, and time. When taking account of the autocorrelation of data within and between dimensions, the notion of closeness often differs for each of the dimensions. Here, we consider a number of approaches to the analysis of such a dataset, which arises from an agricultural experiment exploring the impact of different cropping systems on soil moisture. The proposed models vary in their representation of the spatial correlation in the data, the assumed temporal pattern and choice of conditional autoregressive (CAR) and other priors. In terms of the substantive question, we find that response cropping is generally more effective than long fallow cropping in reducing soil moisture at the depths considered (100 cm to 220 cm). Thus, if we wish to reduce the possibility of deep drainage and increased groundwater salinity, the recommended cropping system is response cropping.  相似文献   

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Isolation and characterization of a genomic DDD mouse interleukin-3 gene   总被引:1,自引:0,他引:1  
K Todokoro  A Yamamoto  H Amanuma  Y Ikawa 《Gene》1985,39(1):103-107
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Isolation of Brazilian marine fungi capable of growing on DDD pesticide   总被引:1,自引:0,他引:1  
The fungi Aspergillus sydowii Ce15, Aspergillus sydowii Ce19, Aspergillus sydowii Gc12, Bionectria sp. Ce5, Penicillium miczynskii Gc5, Penicillium raistrickii Ce16 and Trichoderma sp. Gc1, isolated from marine sponges Geodia corticostylifera and Chelonaplysylla erecta, were evaluated for their ability to grow in the presence of DDD pesticide. Increasing concentrations of DDD pesticide, i.e., 5.0 mg (1.56 × 10−12 mmol), 10.0 mg (3.12 × 10−2 mmol) and 15.0 mg (4.68 × 10−2 mmol) in solid and liquid culture media were tested. The fungi Trichoderma sp. Gc1 and Penicillium miczynskii Gc5 were able to grow in the presence of up to 15.0 mg of DDD, suggesting their potential for biodegradation. A 100% degradation of DDD was attained in liquid culture medium when Trichoderma sp. Gc1 was previously cultivated for 5 days and supplemented with 5.0 mg of DDD in the presence of hydrogen peroxide. However, the quantitative analysis showed that DDD was accumulated on mycelium and biodegradation level reached a maximum value of 58% after 14 days.  相似文献   

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Hereditary hydronephrosis was detected in all of the male mice of DDD inbred strain maintained at the National Institute of Animal Health Japan, but in only a few of the females. From the standpoint that male hormones are related to the development of hydronephrosis in this strain, the incidence and severity of the disease were investigated in gonadectomized mice treated with testosterone. In the males, the incidence of hydronephrosis was 50% (7/14) in the control (gonadectomized) group, and 73.3% (11/15), 100% (13/13) and 100% (12/12) in the 0.1 mg, 3.3 mg and 10 mg treatment groups respectively. The same tendency was observed in the female animals, though the incidence in each group was not so high. In both sexes the degree of severity increased in proportion to the dose of testosterone administrated. Blood testosterone levels were higher in intact DDD mice than in C57BL/6 mice, which had normal kidneys in both sexes. These results suggest that male hormones play a significant role in the development of hydronephrosis.  相似文献   

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Contemporary high dimensional biological assays, such as mRNA expression microarrays, regularly involve multiple data processing steps, such as experimental processing, computational processing, sample selection, or feature selection (i.e. gene selection), prior to deriving any biological conclusions. These steps can dramatically change the interpretation of an experiment. Evaluation of processing steps has received limited attention in the literature. It is not straightforward to evaluate different processing methods and investigators are often unsure of the best method. We present a simple statistical tool, Standardized WithIn class Sum of Squares (SWISS), that allows investigators to compare alternate data processing methods, such as different experimental methods, normalizations, or technologies, on a dataset in terms of how well they cluster a priori biological classes. SWISS uses Euclidean distance to determine which method does a better job of clustering the data elements based on a priori classifications. We apply SWISS to three different gene expression applications. The first application uses four different datasets to compare different experimental methods, normalizations, and gene sets. The second application, using data from the MicroArray Quality Control (MAQC) project, compares different microarray platforms. The third application compares different technologies: a single Agilent two-color microarray versus one lane of RNA-Seq. These applications give an indication of the variety of problems that SWISS can be helpful in solving. The SWISS analysis of one-color versus two-color microarrays provides investigators who use two-color arrays the opportunity to review their results in light of a single-channel analysis, with all of the associated benefits offered by this design. Analysis of the MACQ data shows differential intersite reproducibility by array platform. SWISS also shows that one lane of RNA-Seq clusters data by biological phenotypes as well as a single Agilent two-color microarray.  相似文献   

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Distributed cognition is widely recognized as an approach to the study of all cognition. It identifies the distribution of cognitive processes between persons and technology, among people, and across time in the development of the social and material contexts for thinking. This paper suggests an ectoderm-centric perspective as the basis for distributed cognition, and in so doing redefines distributed cognition as the ability of an organism to interact with its environment for the purpose of satisfying its most basic physiological (internal and external) and social needs in order to survive and sustain itself. Underlying this ectoderm-centric perspective is a proposed theory of reactive and interactive learning.  相似文献   

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