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131.
In cell culture, Rickettsia felis grows only at low temperatures (< 31 °C). Therefore, its ability to enter, survive and grow in cell lines has primarily been tested in cells derived from amphibians and arthropods, which naturally grow at low temperatures, and only infrequently in mammalian cells. We subcultured R. felis in mammalian cells for more than 10 passages using media supplemented with tryptose phosphate broth (TPB) and found that TPB is critical for optimal growth of R. felis in mammalian cells.  相似文献   
132.
Chicory, Chicorium intybus L. (Compositae), is a major field crop in the Eastern Cape Province of South Africa. Several pests feed on the leaves of the plant, resulting in reduced yield. The most important of these are the noctuid moths Helicoverpa armigera (Hübner), Chrysodeixis acuta (Walker), and Trichoplusia orichalcea (F.). The use of attract-and-kill traps offers an alternative to broad-based insecticides in the control of these species. Three fields were treated with normal insecticides and three fields with yellow-baited traps. Eight additional traps were placed in each field, with half of the traps containing the insecticide 2,2-dichlorovinyl dimethyl phosphate (dichlorvos) and half without dichlorvos; and half yellow and half green. Total moth numbers and nonphytophage diversity were measured from these eight traps. Although no differences in H. armigera or T. orichalcea catches were observed between insecticide- and trap-treated fields, numbers of C. acuta and the total number of moths were significantly higher in insecticide-treated fields. Yellow traps containing dichlorvos contained more moths than yellow traps without dichlorvos, or green traps with dichlorvos, or green traps without dichlorvos; but they also contained more nonphytophagous insects. Yellow traps also enhanced the catches of thrips on card traps associated with them. These results offer an opportunity for the South African chicory industry to reduce pesticide applications and thus mitigate environmental impacts.  相似文献   
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Despite numerous investigations, the important structural features of Cell Penetrating Peptides (CPPs) remain unclear as demonstrated by the difficulties encountered in designing new molecules. In this study, we focused our interest on Penetratin and Transportan and several of their variants. Penetratin W48F and Penetratin W48F/W56F exhibit a reduced and a complete lack of cellular uptake, respectively; TP07 and TP10 present a similar cellular uptake as Transportan and TP08, TP13 and TP15 display no or weak internalization capacity. We applied the algorithmic method named PepLook to analyze the peptide polymorphism. The study reveals common conformational characteristics for the CPPs and their permeable variants: they all are polymorphic. Negative, non permeable, mutants share the opposite feature since they are monomorphic. Finally, we support the hypothesis that structural polymorphism may be crucial since it provides peptides with the possibility of adapting their conformation to medium hydrophobicity and or to partner diversity.  相似文献   
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Two mutants of Chlamydomonas reinhardtii, mf1 and mf2, characterized by a marked reduction in their phosphatidylglycerol content together with a complete loss in its Delta3-trans hexadecenoic acid-containing form, also lost photosystem II (PSII) activity. Genetic analysis of crosses between mf2 and wild-type strains shows a strict cosegregation of the PSII and lipid deficiencies, while phenotypic analysis of phototrophic revertant strains suggests that one single nuclear mutation is responsible for the pleiotropic phenotype of the mutants. The nearly complete absence of PSII core is due to a severely decreased synthesis of two subunits, D1 and apoCP47, which is not due to a decrease in translation initiation. Trace amounts of PSII cores that were detected in the mutants did not associate with the light-harvesting chlorophyll a/b-binding protein antenna (LHCII). We discuss the possible role of phosphatidylglycerol in the coupled process of cotranslational insertion and assembly of PSII core subunits.  相似文献   
137.
PURPOSE: We have previously reported a clinical trial on the intravenous injection of autologous activated macrophages (AAM) in 15 patients with renal carcinoma. The present paper concerns scintigraphic investigations performed in 11 of these patients after injection of 111indium oxinate-radiolabeled AAM. METHODS: AAM were prepared from mononuclear cells (MNC) collected by apheresis from patients treated simultaneously with granulocyte-macrophage colony-stimulating factor (GM-CSF). MNC were cultured for 6 days in the presence of GM-CSF and exposed for 18 h to gamma-interferon, the AAM were then separated by elutriation and injected. RESULTS: After intravenous infusion, radiolabeled AAM were transiently retained in the lungs, where they predominated in the first hour. Later on, radioactivity accumulated in liver and spleen and then decreased from the first and second day, respectively. In one patient, two foci of radioactivity were detected in the lungs 1 h after injection, and persisted thereafter. Their association with tumor lesions was uncertain. This observation possibly resulted from the presence of granulocytes in the radiolabeled AAM populations of this patient. It seems that MNC collected from GM-CSF-treated patients and cultured in the presence of GM-CSF enables the differentiation of granulocytes. CONCLUSIONS: A series of 11 investigations confirms the previously reported distribution pattern of intravenously injected AAM. It is possible that in patients treated with hematopoietic cell-mobilizing agents, granulocytes develop in cultures designed to produce monocyte-derived antigen-presenting cells.  相似文献   
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Annick Ohayon 《PSN》2003,1(4):50-61
A sexological movement look form in France in the 1930’s on the initiative of the alienist Dr. Edouard Toulouse. The movement combined the approach of mental hygiene with the “biocratic” ideas of this psychiatrist: to rationalise social and sexual life, through science. Even though this movement founded, an association, instigated a scholarly society, produced its own journal and was supported by eminent personalities of the medical, political and cultural worlds, there is very little historical trace of this movement and consequently it is generally unknown. The author of the article explores the reasons for this oversight and analyses the relationships between this movement and some members of the then emerging French psychoanalytical movement, particularly Dr. Paul Schiff and Princess Marie Bonaparte, from the beginning of 1930’s to the war. The author retraces the socio-political factors which underpinned Toulouse’s initiative and the causes of its apparent failure. This particular case also highlights the relationships between contemporary psychiatry, eugenics and psychoanalysis, and more generally between science, popularization and ideology.  相似文献   
140.
A new species of strictly anaerobic fungus was isolated from the cow rumen. It is characterized by a polycentric thallus, a polynuclear rhizomycelium, mucronate zoosporangia and uniflagellated zoospores. It is also singular in that the sporocysts do not react to the specific lectins of L-fucose, N-acetyl-D-galactosamine and diacetyl chitobiose. These characteristics justify the creation of a new genus.  相似文献   
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