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1.
2.
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。 相似文献
3.
Richard T. Sawyer 《Mycopathologia》1990,109(2):99-109
The initial interaction of Candida albicans with pulmonary tissue of B6D2/F1 mice was investigated. The LD50 for mice challenged intravenously (IV) was approximately 3 × 105 yeasts, whereas the LD50 by the intratracheal (IT) route was in excess of 108 yeasts. Mice challenged IV died of progressive yeast growth in the kidneys. In contrast, mice challenged IT rapidly eliminated the entire inoculum by the first day after challenge. Resident pulmonary alveolar macrophages (PAM) killed upwards of 70% of C. albicans in an in vitro killing assay. At effector: target ratios favoring the effector cell population resident PAM were able to restrict the formation of yeast germ tubes to only 30% of the yeasts, whereas at equivalent ratios virtually all of the intracellular yeasts produced germ tubes. Evaluation of the ability of PAM, harvested from genetically different strains of inbred mice, to kill C. albicans in vitro showed that killing ability was a property of resident PAM from mice with the black 6 background. It was discovered that during the initial stages of infection in vivo, the expression of the F4/80 surface molecule was down regulated, and the expression of the Mac 1 surface molecule upregulated. There were no quantitative changes in expression of either Mac 2, Mac 3, Ly 5 or the 5C6 surface epitopes. Taken together, the data show that pulmonary tissue is quantitatively very resistant to C. albicans infection, because of the ability of resident PAM to rapidly phagocytize and kill yeasts. Killing of C. albicans by resident PAM may be a property of a subset of this mononuclear phagocyte population and was accompanied by alterations in the expression of surface molecules.Presented as part of the Everett S. Beneke Symposium in Mycology, May 27, 1988. 相似文献
4.
Pulmonary alveoler macrophages exposedto very short chrysotile asbestos fibers present a typical cytotoxic response: extracellular releases of lactate dehydrogenase and -galactosidase, and a decrease in cellular ATP content. The objective of this study was to determine if nicotinamide and 3-aminobenzamide, two inhibitors of the ADP-ribosyl transferase, could modify the in vitro toxicity of chrysotilee fibers. After 30 min of pre-exposure with each of the two inihibitors, pulmonary alveolar macrophage monolayers were concominantly exposed for 18 hours to 50g of fibers. It was observed that, in a dose-effect relationship (5 to 30 mM), nicotinamide was very effective in reducing the extracellular liberation of the marker enzymes. At 30 mM, the enzyme releases in the medium had returned to control values; the restoration of cell viability was confirmed by ATP levels. Up to 5 mM 3-aminobenzamide did not provide any protection against chrysotile cytotoxicity. Nicotinic acid, a structural analogue of nicotinamide, but not an inhibitor of the ADP-ribosyl transferase, also showed no protective effect. Nicotinamide and 3-aminobenzamide increased the intracellular NAD+ pools, respectively by 350% and 250%. However, with or without additives, the chrysotile fibers caused a constant and significant decrease in NAD+ levels (40–55 pmoles). These results suggest that the inhibition of the nuclear ADP-ribosyl transferase is not the major mechanism by which nicotinamide protects pulmonary alveolar macrophages against the chrysotile asbestos fibers.Abbreviations 3-AB
3-aminobenzamide
- ADPRT
ADP-ribosyl transferase
- -GAL
-galactosidase
- DTT
dithiothreitol
- FBS
fetal bovine serum
- FMN
flavin mononucleotide
- HEPES
N-2-hydroxyethyl piperazine-N-2-ethanesulfonic acid
- LDH
lactate dehydrogenase
- NAD+
nicotinamide adenine dinucleotide (oxidized form)
- NADH
nicotimide adenine dinucleotide (reduced forms)
- NADPH
nicotimide adenine dinucleotide phosphate (reduced form)
- NAM
nicotinamide
- NIC
nicotinic acid
- ORS
oxygen radical species
- PAM
pulmonary alveolar macrophages
- S.E.
standard error of the mean
- TAPS
tris (hydroxymethyl) methylamino-propane sulfonic acid
- TRIS
tris (hydroxymethyl) aminomethane
- VSF
very short chrysotile fibers 相似文献
5.
Peter J. Somers Richard N. Gevirtz Susan E. Jasin Homer G. Chin 《Applied psychophysiology and biofeedback》1989,14(4):309-318
This investigation assessed the efficacy of a biobehavioral intervention in the adjunctive treatment of mild pregnancy-induced hypertension (PIH), a potentially serious complication of pregnancy in which normotensive women develop hypertension, proteinuria, and edema of unknown etiology late in gestation. Forty-five women with symptoms of PIH were randomly assigned to one of three treatment conditions: bed rest alone (the most common obstetrical treatment), bed rest with individualized compliance enhancement training, or a four-session biobehavioral treatment consisting of bed rest, compliance enhancement training, and individualized thermal biofeedback-assisted relaxation training. Results indicated that while blood pressure for the bed rest and compliance enhancement groups continued to rise and pose an increasing health risk to maternal and fetal well-being, subjects in the biobehavioral group maintained their blood pressure at a significantly lower, and presumably safer, level. The biobehavioral treatment is hypothesized to affect blood pressure levels in subjects with mild PIH through the mediation of the sympathetic nervous system, decreasing peripheral vascular resistance and cardiac output. The results of this investigation suggest that the biobehavioral intervention may be an effective adjunct to bed rest in the treatment of mild PIH remote from term. 相似文献
6.
S. Gulati M. Khullar B. K. Sharma N. K. Ganguly 《Molecular and cellular biochemistry》1996,156(1):37-42
Intracellular free Ca2+ concentration has been shown to be elevated in platelets of patients with essential hypertension. This study was designed to characterize Ca2+-pump activity of the platelet membranes (surface and intracellular) in these patients. A double-blind study was carried out. Untreated and treated (on R-blockers) essential hypertensives were studied in comparison with normotensive control subjects. First degree blood relatives of essential hypertensives were also studied. The Ca2+-activation kinetics of the enzyme showed a significant decrease in the Vmax. (for the plasma- and intracellular membranes) and Km (for the intracellular membranes) in the essential hypertensive patients. Increased platelet membrane cholesterol content was observed in these patients. Lowered Ca2+-efflux by Ca2+-ATPase may lead to elevated intracellular free Ca2+-levels in platelets of essential hypertensives. A lowered Ca2+-ATPase activity may emerge as a marker for essential hypertension. 相似文献
7.
The inorganic contents of bone, brain, erythrocyte, heart, kidney cortex, kidney medulla, liver, lung, muscle and plasma from spontaneously hypertensive rats were compared with those of the same tissues from healthy Sprague-Dawley rats. A general inductively coupled plasma-mass spectrometry method developed for multi-element determinations of most of the elements present in biological tissues was used. Variations were found not only for major elements, as expected, but also for many trace elements in several tissues. 相似文献
8.
Anthony T.W. Cheung Richard B. Moss Geoffrey Kurland Albin B. Leong William J. Novick 《Journal of medical primatology》1993,22(4):257-262
We have recently established a rhesus monkey model of chronic Pseudomonas aeruginosa (PA) endobronchitis by bronchoscopic instillation of PA-embedded agar beads. All experimental animals developed chronic neutrophilic endobronchitis similar to chronic PA endobronchitis in cystic fibrosis (CF). Histopathologic studies further confirmed similarities to chronic PA endobronchitis in CF, including marked peribronchial inflammation, epithelial damage, presence of degraded cilia and ciliary abnormalities, appearance of PA bacterial clusters, mucosal hyperplasia, goblet cell hypertrophy/hypersecretion, airway obstruction, alveolar abnormalities, bronchiectasis, and fibrosis. 相似文献
9.
- 1. 1. The ventilatory and pulmonary gas exchange responses during moderate exercise can be appropriately modelled with first-order dynamics.
- 2. 2. A delay term, reflecting tissue-to-lung transit time, is needed for accurate characterization, however.
- 3. 3. The O2 uptake time constant ( reflects the enzymatically controlled tissue O2 utilization.
- 4. 4. is appreciably longer than , consequent to the tissue CO2 capacitance.
- 5. 5. As typically longer than , transient errors in alveolar and arterial blood gas tensions are predicted: small for PCO2 but much larger for PO2.
- 6. 6. At work rates above the lactate threshold, a slow and delayed component of V̇O2 induces an additional V̇ component (“excess” V̇O2), leading to more rapid fatigue.
- 7. 7. The ventilatory compensation for the metabolic acidemia at these work rates is slow, with compensation being poor for rapid-incremental exercise.
- 8. 8. A justifiable control model of the coupling of ventilation to metabolism must cohere with these demonstrable physiological characteristics.
Keywords: Ventilation; pulmonary gas exchange; excess V̇O2; compensatory hyperpnea; model order 相似文献
10.
The rhesus monkey (Macaca mulatta), which has been found to develop spontaneous obesity, non-insulin dependent diabetes mellitus (NIDDM; Type 2), and hypertension, was used to evaluate the potential blood pressure-lowering effects of captopril as well as the specific effects, if any, on the prediabetic state. Intravenous and oral glucose tolerance testing was carried out with oral captopril dosing. Results showed that captopril significantly decreased both systolic and diastolic blood pressure in all monkeys and significantly decreased fasting plasma glucose levels. Based on these preliminary studies in monkeys, we conclude that captopril exerted antihypertensive effects without adverse effects on glucose metabolism. 相似文献