PET-CT在非完全实性肺结节中的应用价值

肺癌在中国恶性肿瘤的发病率位居第一,随着低剂量薄层CT在肺癌筛查中的广泛应用,临床发现更多表现为非完全实性结节的肺腺癌,目前众多研究使CT影像学特征和肺腺癌病理的关系得到更进一步的认知,虽然CT能对部分非完全实性结节做出定性和定位诊断,但仍有部分非完全实性结节诊断困难,PET-CT结合了病灶的代谢信息和精确的定位信息,从而提高对肺部结节诊断的敏感性、特异性、准确性,综合多个文献PET-CT在非完全实性结节中的诊断分期价值较CT无明显提升,却在评估预后和制定合适手术方案上可以起到一定的作用,本文就PET-CT在SSN中的应用价值进行阐述。     

Purification and characterization of glucose dehydrogenase from the thermoacidophilic archaebacterium Thermoplasma acidophilum.

Glucose dehydrogenase was purified to homogeneity from the thermoacidophilic archaebacterium Thermoplasma acidophilum. The enzyme is a tetramer of polypeptide chain Mr 38,000 +/- 3000, it is catalytically active with both NAD+ and NADP+ cofactors, and it is thermostable and remarkably resistant to a variety of organic solvents. The amino acid composition was determined and compared with those of the glucose dehydrogenases from the archaebacterium Sulfolobus solfataricus and the eubacteria Bacillus subtilis and Bacillus megaterium. The N-terminal amino acid sequence of the Thermoplasma acidophilum enzyme was determined to be: (S/T)-E-Q-K-A-I-V-T-D-A-P-K-G-G-V-K-Y-T-T-I-D-M-P-E.     

Antibodies to pollen exines

A polyclonal antiserum and monoclonal antibodies have been prepared to purified pollen exines of Calocedrus decurrens Florin. The location of the antigen is in the exine, as shown by light-and electron-microscopic immunocytochemistry. The greatest reduction in antibody binding follows treatment of the exine with chemicals known to alter sporopollenin. These results provide evidence that sporopollenin is antigenic. Exines of ten species of gymnosperms and angiosperms also bound the polyclonal antiserum, indicating similarity of sporopollenin structure.     

Breakpoint localization of the marker chromosome associated with the cat eye syndrome.

We investigated the breakpoints involved in the generation of the supernumerary bisatellited chromosome associated with the Cat Eye syndrome. In situ hybridization of DNA probes from band 22q11 revealed that, for two individuals with the Cat Eye syndrome, both breakpoints for the bisatellited chromosome were distal to the DNA sequence corresponding to probe D22S9 and proximal to the immunoglobulin C lambda genes and to at least one subgroup of the V lambda genes.     

Applications of fluorochromes to pollen biology. II. The DNA probes ethidium bromide and Hoechst 33258 in conjunction with the callose-specific aniline blue fluorochrome

Techniques are described for detection of pollen grain and pollen tube nuclei using the fluorescent DNA probes ethidium bromide or Hoechst 33258, in conjunction with the aniline blue fluorochrome sirofluor, which stains the callose component of pollen tube walls and plugs. The DNA probes, which may be used either as vital stains or following fixation, permit discrimination between vegetative and generative or sperm nuclei. Double staining with sirofluor allows location of nuclei within pollen tubes grown in vitro, and when used after pollination enables the viewer to discriminate between nuclei within the pollen tube vs. nuclei of the pistil tissue.     

Some observations on the periodate oxidation of amino compounds

Various aliphatic and aromatic amines are oxidized by sodium metaperiodate and these reactions have been studied quantitatively in acidic, unbuffered and basic media. Significant differences have been observed between the behaviour of aliphatic and aromatic amines. Certain compounds also behaved differently under acidic and basic conditions. These reactions are related to the periodate oxidation of amino acids and, from observations on a number of glycine derivatives, a reaction mechanism is proposed for this process.     

Studies on a glycopeptide from ovalbumin

1. The structure of the carbohydrate component of the glycopeptide isolated from the proteolytic digest of ovalbumin has been investigated by chemical and enzymic methods. 2. The results are consistent with the presence of a single carbohydrate prosthetic group, linked through its reducing end group to the peptide chain. 3. Further, all the 2-amino-2-deoxy-d-glucose units appear to be in the N-acylated form, the phenolic hydroxyl group of tyrosine is free and the ω-carboxyl group of aspartic acid is substituted. 4. The carbohydrate component has a branched-chain structure, the two non-reducing ends being terminated by a d-mannopyranosyl and a 2-acetamido-2-deoxy-d-glucopyranosyl residue respectively. 5. The terminal d-mannopyranosyl unit is probably linked through at least one other d-mannopyranosyl residue to the remainder of the carbohydrate.     

α-d-allopyranosyl β-d-fructofuranoside (allo-sucrose) and its derivatives

Reduction of 3-ketosucrose (1) with sodium borohydride gave mainly α-d-allopyranosyl β-d-fructofuranoside (2) characterized as its octabenzoate. Using sodium borodeuteride, [3-²H]allo-sucrose (5) and [3-²H]sucrose (6) were obtained in the ratio 12:1. The mixture was fractionated on Dowex-50 X8 resin (Ca²⁺ form), and the [3-²H] derivatives were isolated as their octa-acetates. Inspection of the ¹³C-n.m.r. spectra of 5 and 6 enabled the C-3 signals to be assigned. allo-Sucrose (2) was more readily obtained by oxidation of sucrose with dimethyl sulphoxide-acetic anhydride followed by reduction with sodium borohydride and fractionation on Dowex-50 X8 (Ca²⁺) resin. Tritylation of 2 followed by acetylation gave, after chromatography, the 6,1′,6′-tritrityl ether (9, 10%), the 6,6′-ditrityl ether (10, 26%), and a mixture of monotrityl ethers (20%). Hydrogenolysis of 9 and 10 gave the penta-acetate and hexa-acetate, respectively, with no detectable migration of AcO-4. Treatment of 2 with sulphuryl chloride at -50° gave the 6,6′-dichloride.     

The site of VX2 tumor transplantation affects the development of hypercalcemia in rabbits

The relationship between plasma levels of 15-keto-13, 14-dihydro-prostaglandin E₂ (15K-H₂-PGE₂) and serum calcium levels was studied in nontumor-bearing rabbits and in rabbits bearing the VX₂ carcinoma intramuscularly and intra-abdominally. The plasma levels of 15K-H₂-PGE₂ in the two groups of tumor-bearing animals did not vary significantly but was several fold greater than in nontumor-bearing rabbits. Rabbits bearing the VX₂ carcinoma intramuscularly developed hypercalcemia between the second and third week after implantation of neoplastic tissue and remained hypercalcemic until they expired. The serum calcium levels in rabbits bearing the VX₂ carcinoma intra-abdominally did not vary significantly from those of nontumor-bearing rabbits. The differences in the serum calcium levels in rabbits bearing the VX₂ carcinoma at intramuscular and intra-abdominal implant sites may be related to different extents of metabolism by the lung and by the liver of prostaglandin E₂ or other cyclooxygense products of polyenoic fatty acids produced by the tumor.