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BYOUNG S. KWON KACK K. KIM RUTH HALABAN RICHARD T. PICKARD 《Pigment cell & melanoma research》1994,7(6):394-397
Pmel 17 cDNA clones, isolated from wild-type and si/si murine melanocytes, were sequenced and compared. A single nucleotide (A) insertion was found in the putative cytoplasmic tail of the si/si Pmel 17 cDNA clone. This insertion is predicted to alter the last 24 amino acids at the C-terminus and to extend the Pmel 17 protein by 12 residues. The mutation was confirmed by the sequence of the PCR-amplified genomic region including the mutation site. Silver Pmel 17 was not recognized by antibodies directed toward the C-terminal amino acids of wild-type Pmel 17, indicating a defect in this region. These results indicate that silver Pmel 17 protein has a major defect at the carboxyl terminus. 相似文献
993.
RICHARD W. SAGEBIEL 《Pigment cell & melanoma research》1994,7(2):101-103
A patient survival model is proposed which allows visualization of a data base, and which includes only routine and commonly recorded attributes in most melanoma clinics. It is proposed that a network of such data be collected for meta-analysis (MELNET), which could make stratification within the individual subsets more significant by virtue of the larger numbers. Such a network could then be fully tested in various melanoma clinics for clinical usefulness. 相似文献
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BLANKE MICHAEL M.; BACHER WOLFGANG; PRING RICHARD J.; BAKER EDWARD A. 《Annals of botany》1996,78(5):599-604
Kohlrabi (Brassica oleracea var.gongylodes) plants were grownin the greenhouse under autumn conditions and fertilized eitherwith pellets containing nitrogen as 40% ammonium sulphate and60% urea or with nutrient solution containing nitrogen predominantlyas nitrate. Plants given nitrogen as ammonium ions developedglaucous leaves compared to those supplied with nitrate whichformed glossy leaves. Ammonium-induced glaucousness was theresult of a two-fold increase in the amount of epicuticularwax and a markedly altered fine structure. Leaves from ammoniumfertilized kohlrabi plants also showed a 21% increase in chlorophyllcontent together with a reduction in the chlorophyll a:b ratioand decreased ground state fluorescence compared to plants suppliedwith nitrate. Photosynthesis and stomatal transpiration wereunaffected by the form of supplied nitrogen. Brassica oleracea ; chlorophyll; chlorophyll fluorescence; epicuticular wax; glaucousness; photosynthesis; transpiration 相似文献
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Abstract. Little is known about the nature of injury due to cold shock, or its prevention by rapid cold-hardening, in insects. To understand these phenomena better at the system level, physiological and behavioural comparisons were made between control, cold shock injured, and rapidly cold-hardened flesh flies, Sarcophaga crassipalpis Macquart (Diptera, Sarcophagidae). Cold shock impaired the proboscis extension reflex in response to 0.125,0.5 and 1.0 M sucrose solutions. Cold shock-injured flies were unable to groom effectively and spent only 12.5% of the first 5 min following general dust application producing ineffectual leg movements. In contrast, control and rapidly cold-hardened flies exhibited normal grooming behaviour spending 92.4% and 94.1% of the first 5 min following generalized dust application grooming. Cold shock also decreased the mean resting membrane potential of tergotrochanteral muscle fibres from -65.9 mV in control flies to -41.6 m V. Conduction velocities of the three motor neurone populations innervating the tergotrochanteral muscle were all significantly lower in cold-shocked flies than in control or rapidly cold-hardened flies. Finally, cold shock impaired neuromuscular transmission as evidenced by a lack of evoked end plate potentials. 相似文献
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