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Idiopathic pulmonary hemosiderosis is a rare condition manifested by recurrent pulmonary hemorrhage of unknown cause, diffuse radiologic abnormalities, cough, hemoptysis and moderate to severe hypochromic anemia. Diagnosis can be confirmed by iron stains of the sputum or lung aspiration or by biopsy. Prolonged spontaneous remission may occur without the use of corticosteroid therapy. Studies here reported indicated that the anemia is hypochromic and microcytic anemia of blood loss and iron deficiency, in spite of the presence of large amounts of iron in the pulmonary tissue. Correction of the anemia by intensive iron therapy and transfusion is considered an important part of therapy. 相似文献
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Maurice Partridge 《BMJ (Clinical research ed.)》1959,1(5126):915-916,917
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Maurice Campbell 《BMJ (Clinical research ed.)》1959,1(5133):1341-1342
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ß-Glucuronidase (GUS) and chloramphenicol acetyl transferase (CAT) were used as reporter proteins in protoplasts from embryogenic suspension cultures of Picea glauca (Moench) Voss (white spruce). Plasmid DNA enclosing chimeric GUS and CAT constructs, using the cauliflower mosaic virus 35S promoter, was introduced into Picea glauca protoplasts using polyethylene glycol (PEG). Transient expression was detected 12 to 40 h after PEG-mediated DNA delivery. Dose-response curves using covalently closed circular plasmid DNA, in the absence of carrier DNA, have been obtained for each of these reporter genes. Linearized plasmid DNA gave lower levels of expression than covalently closed circular plasmid DNA when assayed 40 h after PEG-mediated DNA transfer. The use of carrier DNA (herring sperm DNA), in combination with covalently closed circular plasmid DNA, increased the level of expression of GUS by about 50%. CAT expression was enhanced if PEG-mediated delivery was performed on ice rather than at room temperature. The highest level of expression for CAT, and the lowest signal-to-noise ratio, was found 24 h after PEG-mediated DNA transfer. Both GUS and CAT provided results that were quantifiable and can therefore be used as reporter genes in Picea glauca.Abbreviations CAT
chloramphenicol acetyl transferase
- GUS
ß-glucuronidase
- CaMV
cauliflower mosaic virus
- NOS
nopaline synthase
- CCC
covalently closed circular DNA
- L
linear DNA
- PEG
polyethylene glycol
- HS
herring sperm DNA
- P
protoplasts
- PCM
protoplast culture medium
- MES
morpholinoethane-sulfonic acid
- Cm
chloramphenicol
- Ac
acetylated
- MUG
4-methyl umbelliferyl ß-D-glucuronide
- TLC
thin layer chromatography 相似文献