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。     

Expression of neuronal acetylcholine receptor polypeptidesin vitro

1. Translation of poly(A) RNA extracted from the nervous tissue of locusts in a reticulocyte lysate system led to polypeptides with a broad spectrum of molecular weights. 2. Using anti-locust acetylcholine receptor (AChR) antisera, polypeptides with a molecular weight of about 50,000 were immunoprecipitated. These peptides comprised about 0.3% of the total translation products. 3. Cotranslational incubation with pancreatic rough microsomes resulted in a glycosylated 60,000-dalton immunoprecipitate. 4. Density-gradient analysis of in vitro synthesized and glycosylated receptor polypeptides indicated that no assembly of subunits had taken the place under the in vitro conditions.     

烟青虫感染核型多角体病毒后围食膜的病变

昆虫的围食膜是衬在昆虫中肠内一种网状的结构,它可充作虫体抵御外来病原侵染的一道屏障。关于鳞翅目昆虫幼虫感染了昆虫病毒后围食膜的病变问题,国内外鲜有报道。尤锡镇和康慧娟(1985)曾以实验证明家蚕围食膜对核型多角体病毒有灭活作用,而且认为核型多角体病毒不能侵染和破坏围食膜。Derksen和Granados(1988)则证明染病幼虫的围食膜因不同杆状病毒(包括两种核型多角体病     

Comparison of acetylcholine and alpha-bungarotoxin binding sites in insects and vertebrates

1. The nervous tissue of locusts contains high affinity as well as low affinity binding sites for acetylcholine which display a similar nicotinic pharmacology. 2. Hill plot analysis indicated a non-cooperative binding of acetylcholine. 3. In membrane preparations from locust ganglia and mouse brain the number of binding sites for ACh was about ten fold lower than for BGTX, whereas in membranes from electric tissue both sites occurred in similar concentrations. 4. Drug binding studies suggest that the high affinity binding sites for ACh and BGTX in preparations from insect and mouse are different; whereas in electric tissue both sites are very similar. 5. Precipitation experiments using immobilized BGTX and specific antibodies indicated that in insect nervous tissue as in electric tissue the ACh and BGTX binding sites are located on the same receptor molecule and occupy distinct partially overlapping binding sites, whereas in the vertebrate brain both sites are located on distinct binding proteins.     

Developmental and Regional Expression of NMDA Receptor Subtypes Containing the NR2D Subunit in Rat Brain

Abstract: The regional and developmental expression of NMDA receptors containing the NR2D subunit was analyzed on the level of the subunit mRNA and protein in rat brain. RNase protection experiments indicated that among two proposed splice variants of the NR2D subunit, only the NR2D-2 subunit is expressed. The regional distribution of the NR2D subunit protein was visualized with a newly developed NR2D-2 subunit-specific antiserum on brain sections using the histoblot technique. In adult brain, NR2D immunoreactivity was mainly restricted to diencephalic, mesencephalic, and brainstem structures. During postnatal development, the NR2D subunit was detected transiently in certain regions, such as the ventro-basal complex of the thalamus, hippocampus, inferior colliculus, and brainstem reticular formation, suggesting that NR2D subunit-containing receptors play a role in these brain areas only during development. The level of NR2D subunit mRNA and protein decreased during late postnatal development. However, significant levels of NR2D subunit mRNA and protein were present in adulthood, in particular, in the globus pallidus, thalamus, subthalamic nuclei, and superior colliculus. These results indicate a functional relevance for NMDA receptors containing the NR2D subunit in the developing and adult brain, although its expression in the adult brain is less prominent and restricted to a few brain areas.     

NMDA Receptor Heterogeneity During Postnatal Development of the Rat Brain: Differential Expression of the NR2A, NR2B, and NR2C Subunit Proteins

Abstract: Changes in the expression of the NMDA receptor subunits (NRs) NR2A, 2B, and 2C were investigated in histo blots of the developing rat brain with subunit-specific antisera. At birth, the NR2B subunit was detected almost ubiquitously, the NR2A subunit staining was faint and restricted to the hippocampus, cerebral cortex, and striatum, and no NR2C subunit immunoreactivity was detected. During the first 3 postnatal weeks, the NR2B subunit became confined to forebrain structures, whereas the NR2A immunoreactivity became abundantly expressed throughout the brain. The NR2C immunoreactivity emerged 5 days after birth in the olfactory bulb, thalamus, and vestibular nuclei and became very intense after 10 days in cerebellar granule cells, its primary site of expression in adulthood. After 3 weeks, NR2A and NR2B immunoreactivity decreased to adult levels, whereas NR2C immunoreactivity remained unchanged. The patterns of distribution of the subunit proteins were in agreement with those of their corresponding mRNAs, as monitored by in situ hybridization histochemistry, although the mRNA translation appeared to be delayed by several days in certain areas. Our results reveal a progressive increase in the heterogeneity of NMDA receptors due to the comparably late onset of NR2A and NR2C subunit expression and by the area-specific rearrangement of NR2B subunit expression following birth.     

Scanning electron microscopic observations on cells grown in vitro. VII. HeLa cells can penetrate Wi38 fibroblasts

When HeLa cells are seeded on a preexisting monolayer of Wi38 fibroblasts, the HeLa cells "try" to get into direct contact with the glass substrate. Once on top of a flat fibroblast the HeLa cell can either migrate from the fibroblast to settle between two fibroblasts on glass or somehow stimulate the underlying cells to retract. In a few cases the HeLa cell directly penetrates the fibroblast, "melting" its way through the underlying cell. The mechanism of this phenomenon which has never been described before in this combination is discussed.     

New form of adrenoleukodystrophy

Summary Male and female siblings demonstrated similar facial features and had seizures from birth. Neurologic development, which was delayed, began to deteriorate at 1 year. Sudden death occurred at 2 8/12 and 2 3/12 years of age associated with respiratory infections. Tanning of the skin was noted 2 months before death in the first child. In the second child, blood cortisol levels failed to increase after intravenous ACTH administration, and computerized axial tomography (CAT) scans were normal.At autopsy both patients demonstrated adrenal atrophy and degenerative changes of the white matter throughout the neuraxis. We propose that these siblings have a new form of adrenoleukodystrophy that can be distinguished from the X-linked form by onset at birth, clinical appearance, and pattern of inheritance.A comparison of these cases with a second disorder, Zellweger's syndrome, suggests that a distinctive phenotype is associated with intrauterine degeneration of white matter.     

Interactions among coexisting larval Odonata: an in situ experiment using small enclosures

Field experiments using small replicated enclosures focused on interactions between larval populations of Epitheca cynosura and Ladona deplanata (Odonata: Anisoptera) — two species that emerge in early spring. The presence of Epitheca reduced the total biomass of Ladona, but Ladona had no significant effect on Epitheca. These early-emerging species reduced the biomass of small instars of late-emerging Anisoptera which colonized enclosures during the experiments; and the late-emerging Anisoptera seem to have inhibited colonization by Zygoptera larvae. Results are consistent with the importance of predatory (cannibalism or mutual predation) interactions in this community.