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211.
Scale morphology, growth and the squarnation chronology are described for the hermaphroditic fish Rivulus marmoratus reared in the laboratory. The scales are round or oval shaped cycloid type, and their sizes are about 0.3–1.0 mm in diameter. The number of ridges increases more rapidly relative to the body growth of the fish in early stages, but this increase is proportionate to growth subsequently. Three loci of scale development have been identified. The scales first appeared on the center of the parietal region at 8 days after hatching. The second locus of scale formation was on the lateral line of the posterior end of the caudal peduncle. A third locus was later observed on the lower right corner of the operculum: The final squamation was completed at 6 weeks after hatching.  相似文献   
212.
213.
Besides Clostridium thermoaceticum and C. formicoaceticum other resting acetogenic clostridia such as C. aceticum and C. thermoautotrophicum and to a lesser extent non-clostridial acetogens such as Butyribacterium methylotrophicum and Eubacterium limosum were able to reduce propionate to propanol at the expense of carbon monoxide or formate. Methylviologen usually increased the reduction rate. Ten M molybdate in the growth medium decreased this capability for C. thermoaceticum but increased it or had no effect for the other organisms. Ten M tungstate in the growth medium increased the aldehyde oxidoreductase activity in all organisms. Crude extracts of C. thermoaceticum cells grown in the presence of 10 M or 1 mM molybdate showed by ELISA the same or even a 4 fold concentration of aldehyde oxidoreductase in the latter case. However, the enzymic activity was very low in both cases. Omission of dithionite in the growth medium diminished the antigen by a factor of about 8. The immunological distance between the enzyme from C. thermoaceticum and C. thermoautotrophicum was rather low but very large to C. formicoaceticum and undeterminably large to the other organisms.Abbreviations Ald-DH aldehyde dehydrogenase - AOR aldehyde oxidoreductase - CO-DH carbon-monoxide dehydrogenase - ELI-SA enzyme-linked immunosorbent assay - FDH formate dehydrogenase - MV methylviologen - V++ oxidised - V+. reduced viologen  相似文献   
214.
Free vascularized bone grafts have revolutionized mandibular reconstruction, yet their use in all mandibulectomy patients is not always necessary. A recently developed alternative to bony reconstruction has been the use of the AO reconstruction plate. We compared the use of the AO reconstruction plate with immediate free bone graft mandibular reconstruction in 31 patients. Reconstruction plates were used in 20 and immediate free bone grafts were used in 11 patients. The overall success rate for use of the plate was 15 of 20 (75 percent). There were 6 anterior reconstructions, of which only 2 (33 percent) were successful. This is opposed to 13 of 14 (93 percent) lateral reconstructions that were successful in lateral plate placements. There were 11 immediate composite free flaps: 4 iliac crest, 4 scapula, 2 fibula, and 1 composite radial forearm flaps. Six repairs were for anterior defects, and there were 5 full-thickness defects, 3 of which were in the anterior position. All 11 flaps were successful. In conclusion, we believe the reconstruction plates are a useful adjunct for mandibular replacement in the head and neck cancer patient but should be reserved for lateral defects. For anterior reconstructions, even in patients with locally advanced disease, free-tissue transfer of composite osteocutaneous flaps is the reconstructive method of choice.  相似文献   
215.
A 2.4 kb fragment containing the 5'-flanking region and the 5'-noncoding sequence of the Vicia faba legumin gene LeB4 mediates high level seed-specific expression in transgenic tobacco plants. Deleted derivatives of this legumin upstream sequence were fused to the npt-II reporter gene to determine the tissue-specific activity of the chimeric constructs in stably transformed tobacco plants. The results indicate the presence of positive regulatory, enhancer-like cis elements within 566 bp of the upstream sequence. Most importantly, however, these elements are only fully functional in conjunction with the core motif CATGCATG of the legumin box around position -95, since destruction of the motif by a 6 bp deletion in an otherwise intact 2.4 kb upstream sequence drastically reduces expression in seeds. At the same time, low level expression in leaves is observed. The occurrence of similar CATGCATG consensus cis elements with alternating purine and pyrimidine base pairs in front of several other plant genes suggests a functional role of the motif in a wider range of plant promoters.  相似文献   
216.
Conidia of the speciesFusarium culmorum /W.G.Sm./ Sacc. andFusarium graminearum Schwabe are characterized by variability in zearalenone production and dimensions depending on the substrate. The sporulation of isolates from some wheat eultivars have been deprived in vivo and in vitro in the first passage, but not their pathogenicity and toxic metabolites production. Nonsporulating strains produced lower quantités of zearalenone than sporulating ones. Liquid filtrates of such nonsporulating strains had a high phytotoxic effect on wheat caryopses. The crystalline toxin DAS /0,25 ug/ml/ had low phytotoxic effect on wheat caryopses.  相似文献   
217.
Maize cobs withFusarium ear rot were collected at 1986 season and five infected byFusarium graminearum were analyzed for presence of triohothecenes and zearalenone. Collected material was subsampled forFusarium damaged kernels and corresponding axial stems and healthy looking kernels. All investigated cobs contained deoxynivalenol (DON) (range 18.0–131.5 mg/kg) and zearalenone (ZEA) (range 0.38–2.17 mg/kg), in four cobs 15-acetyl-deoxynivalenol (15-AcDON) (range 5.2–6.2 mg/kg) was present and two cobs besides three all metabolites contained 3-acetyl-deoxynivalenol (3-AcD0N) (range 0.5–0.8 mg/kg).The average of individual toxins amount in axial stems: in mg/kg was equal to: DON — 110.36, ZEA — 4.57, 15-AcD0N — 16.66, and 3-AcD0N — 1.32.Fusarium damaged kernels contained in average the following amount (mg/kg) of: DON 77.00, ZEA 0.98, 15-AcD0N 3.78 and 3-AcD0N 0.06. Healthy looking kernels contained DON 1.96 mg/kg and ZEA 0.07 mg/kg only. Cooccurrence of 3-AcDON and 15-AcDON in two samples was an interesting finding. The amount of DON in total cob was highly correlated (r = 0.94) with percentage ofFusarium damaged kernels in given ear.  相似文献   
218.
The biosynthesis and processing of the vacuolar (lysosomal) acid trehalase (molecular mass about 220 kDa) was followed in vivo using mutants conditionally defective in the secretory pathway. A precursor of 41 kDa was found in sec61 mutant cells deficient in translocation of secretory protein precursors into the lumen of the endoplasmic reticulum. Endoglycosidase H and N-glycosidase F treatment of purified acid trehalase in vitro resulted in a 41 kDa band, indicating that the precursor form found in sec61 mutant cells corresponds to the carbohydrate-free form of the enzyme. sec 18 mutant cells, blocked in the delivery of secretory proteins from the endoplasmic reticulum to the Golgi body accumulate a form with a molecular mass of 76 kDa which probably corresponds to a partially glycosylated precursor of the mature acid trehalase. This precursor partially disappears in favour of the appearance of a higher molecular weight component of 180 kDa in sec7 mutants which are blocked in the delivery step of secretory proteins from the Golgi body to the vacuole. In wild-type cells the fully glycosylated mature form of acid trehalase of about 220 kDa was observed accompanied by some 180 kDa and 76 kDa material.  相似文献   
219.
220.
Summary After a decrease and extinction due to deforestation the population has been reestablished by releasing captive-bred owls. Now about 40 territories are occupied with an average density of 0,8–1,0 territories/10 km2. Highest density: 17 territories/80 km2.  相似文献   
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