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51.
肺血管扩张在肝肺综合征发病机制中作用的研究进展   总被引:3,自引:0,他引:3  
肺血管扩张是肝肺综合征的主要发病机制,然而导致HPS肺血管扩张的机制相当复杂,至今仍不清楚.目前认为肺血管内巨噬细胞聚积和雌激素升高导致的血管活性因子增多和活性增强可能与此有关,近年来这方面的研究很多,本文对此作一综述.  相似文献   
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OBJECTIVE: To study the expression of neuron-specific enolase (NSE) and olfactory marker protein (OMP) in the developing olfactory mucosa of human fetuses. METHOD: The expression of NSE and OMP in the olfactory mucosa of 6 human fetuses (12, 16, 20, 24, 28 and 34 weeks) was studied using the technique of immunohistochemistry. RESULTS: NSE immunological positive reactions were seen in all 6 fetal mucosa from gestational 12 (G12) to G34, with plenty of positive-stained dual-pole neuron cells. At G12, the positive cells aligned tightly, the cell bodies were localized in the lower portion of olfactory epithelium and the positive-stained area occupied upper 2/3 of fetal nasal mucosa. With the development, the positive cells gradually became multilayer, but the density and the relative area of positive-cells reduced. At G34, the positive cells were located only in upper 1/3 of nasal mucosa. OMP-positive reactions were localized in a few dual-pole neurons at G12, the number was much less than NSE-positive cells in the same fetus. With the development, the OMP-positive cells gradually increased with most of the cell bodies located in the upper portion of epithelium, but number still relatively less than the NSE-positive cells at the same age. CONCLUSION: At G12, there were lots of olfactory neuron in the olfactory mucosa and only a few olfactory neurons had became mature. With the development, the olfactory epithelial area reduced but the number of mature olfactory neurons increased. At the last trimester, fetal olfactory sensor was almost matured.  相似文献   
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Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.  相似文献   
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The ability of a peptide hormone to affect many different intracellular targets is thought to be possible because of the modular organization of signal transducing molecules in the cell. Evidence for the presence of signaling modules in metazoan cells, however, is incomplete. Herein we show, with morphology and cell fractionation, that all the components of a mitogen-activated protein kinase pathway are concentrated in caveolae of unstimulated human fibroblasts. Addition of platelet-derived growth factor to either the intact cell or caveolae isolated from these cells stimulates tyrosine phosphorylation and activates mitogen-activated protein kinases in caveolae. The molecular machinery for kinase activation, therefore, is preorganized at the cell surface of quiescent cells.  相似文献   
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We have investigated several phenotypic features of the catecholamine-positive (CA+) cell population that develops in quail neural crest cultures. The number, spatial distribution, and morphology of CA+ and tyrosine hydroxylase-positive (TH+) cells are similar at all ages examined, suggesting that these 2 cell classes are identical. Neither CA+ nor TH+ cell bodies or processes were stained using antisera that recognize the 70 or 160 kDa subunits of chicken neurofilament protein. Other cell bodies and fibers in the cultures (which were CA- and TH-) were stained with these neurofilament antisera. The uptake and storage of 3H-norepinephrine by neural crest cultures containing CA+ cells were inhibited in the presence of desmethylimipramine and by incubation at 0 degrees C, but were unaffected by normetanephrine. Overnight treatment with reserpine eliminated histochemically detectable CA fluorescence from the cultures. Chronic reserpine treatment from day 2 to 7 in vitro prevented the appearance of CA+ cells, while normal numbers of TH+ and somatostatin-like immunoreactive (SLI) cells developed. The number and light-microscopic morphology of the CA+ cells that developed in these cultures were not dramatically altered by either exogenous NGF or 6-hydroxydopamine. Using the method of Grillo et al. (1974), we have demonstrated that the CA+ cells observed in the light microscope corresponded to cells containing abundant cytoplasmic granular vesicles (GV) characteristic of catecholamine storage granules observed in other systems. The GV diameters were quite similar in cells examined after 5, 7, 14, and 21 d in vitro. Most GV were 50-200 nm in diameter and were distributed in a unimodal manner, with the observed modal values in the range of 85-115 nm at the ages examined. The number of GV/micron2 of cytoplasmic area remained quite constant at all ages examined. These data, taken together with other available information, suggest that the CA+ cells that differentiate in our neural crest cultures resemble, in many respects, the small, intensely fluorescent cells found in autonomic ganglia and extra-adrenal chromaffin tissue of many species. At present, we do not know if the CA+ cells that differentiate in our neural crest cultures are a stable endpoint of development or whether they are a developmental intermediate in adrenergic differentiation that is normally observed only transiently during the development of avian sympathetic ganglia in vivo, but that can persist under our tissue culture conditions.  相似文献   
60.
N┐(4┐乙氧苯基)苯甲酰胺类化合物的合成及抗炎、抗变态反应活性研究周玉新1)党永红刘建飞2)徐颖刘百里(沈阳药科大学制药系,沈阳110015)郑文义(东北第六制药厂,沈阳110043)1981年,刘百里等〔1,2〕发现和研制的新药益肤酰胺,经药理实...  相似文献   
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