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51.
Yet another application of suction lipectomy equipment is presented to remove the pathologic tissue in cherubism. Owing to the variations of consistency of the material in this condition, this technique may not be successful in all patients, but it is certainly recommended when indicated.  相似文献   
52.
Purification of nine plasma proteinase inhibitors and one zymogen from a single batch of human plasma, using affinity chromatography has been accomplished. Those isolated were plasminogen (lysine-Sepharose), alpha-2-antiplasmin (plasminogen-Sepharose), high and low molecular weight kininogens (CM-papain-Sepharose), alpha-2-macroglobulin (Zn++ chelate-Sepharose), alpha-1-proteinase inhibitor, alpha-1-antichymotrypsin, Cl-inhibitor, inter-alpha-trypsin inhibitor (Blue-Sepharose) and antithrombin III (heparin-Sepharose). Alpha-2-macroglobulin and alpha-1-proteinase inhibitor required gel filtration as additional purification steps. Each protein was recovered in both high yield and purity.  相似文献   
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Whole-cell membrane currents were recorded from olfactory receptor neurons from the neotenic salamander Necturus maculosus. Cyclic nucleotides, released intracellularly by flash photolysis of NPE-caged cAMP or NPE-caged cGMP, activated a transient chloride current. The chloride current could be elicited at constant voltage in the absence of extracellular Ca2+ as well as in the presence of 3 mm intracellular Ca2+, suggesting that the current did not require either voltage or Ca2+ transients for activation. The current could be elicited in the presence of the protein kinase inhibitors H-7 and H-89, and in the absence of intracellular ATP, indicating that activation was independent of protein kinase A activity. These results suggest that Necturus olfactory receptor neurons contain a novel chloride ion channel that may be directly gated by cyclic nucleotides. Received: 12 November 1996/Revised: 4 April 1997  相似文献   
56.
Long terminal repeat (LTR) retrotransposons are closely related to retroviruses, and their activities shape eukaryotic genomes. Here, we present a complete Lotus japonicus insertion mutant collection generated by identification of 640 653 new insertion events following de novo activation of the LTR element Lotus retrotransposon 1 (LORE1) ( http://lotus.au.dk ). Insertion preferences are critical for effective gene targeting, and we exploit our large dataset to analyse LTR element characteristics in this context. We infer the mechanism that generates the consensus palindromes typical of retroviral and LTR retrotransposon insertion sites, identify a short relaxed insertion site motif, and demonstrate selective integration into CHG‐hypomethylated genes. These characteristics result in a steep increase in deleterious mutation rate following activation, and allow LORE1 active gene targeting to approach saturation within a population of 134 682 L. japonicus lines. We suggest that saturation mutagenesis using endogenous LTR retrotransposons with germinal activity can be used as a general and cost‐efficient strategy for generation of non‐transgenic mutant collections for unrestricted use in plant research.  相似文献   
57.
A major lysine tRNA with a CUU anticodon in insect mitochondria   总被引:4,自引:1,他引:3       下载免费PDF全文
We have sequenced a lysine tRNA from mosquito mitochondria that has the anticodon CUU. The preponderance of AAA lysine codons in insect mitochondrial genes, the parsimonious organization of the genomes, and the fact that this tRNA is a major component of the mosquito mitochondrial tRNA complement, lead us to suggest that the CUU anticodon recognizes AAC and AAA codons.  相似文献   
58.
A novel low molecular weight (“3 SE”) RNA associated with hamster cell mitochondria has been partially characterized. It was present at approx. 1:1 molar ratio with structural mitochondrial ribosomal RNA; it was unmethylated; and it resembled other mitochondrial RNA fractions in having a low content of G + C. These findings support the idea that 3 SE RNA is a mitochondrial equivalent of 5 S ribosomal RNA.  相似文献   
59.
Degree of methylation of mitochondrial ribosomal RNA   总被引:1,自引:0,他引:1  
Dubin DT  Friend DA 《FEBS letters》1971,18(2):287-289
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60.
This paper describes recent success in performing hysterosalpingography in cynomolgus monkeys. The animals were anesthesized, and a needle was manipulated through the cervical canal into the endometrial cavity for injection of contrast material. Difficulties in threading the needle through the canal were due to several blind pouches formed by folds in the cervical mucosa. The uterine lumen and both tubes could be visualized in over 75% of the cases. The study demonstrates that the hysterosalpingography technique can be performed satisfactorily in cynomolgus monkeys.  相似文献   
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