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101.
Most models suggest that the cell of origin of papillary carcinoma is the mature thyroid follicular epithelial cell. In a recent study, p63 was detected in papillary carcinoma, Hashimoto's thyroiditis, and in squamoid aggregates and solid cell nests (SCNs), embryonic remnants found sporadically in the fully developed thyroid. In the present study, the relationship between solid cell nests and papillary carcinoma was investigated further. Four-micrometer sections from 88 routinely fixed and processed archival thyroidectomy specimens were pretreated with citric acid pH 6.0 for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained with a streptavidin-biotin kit and diaminobenzidine as chromogen and were counterstained with hematoxylin. Squamoid aggregates or SCNs were noted in 21 specimens. Several morphologic variants of SCNs were found, all of which displayed p63 positivity. These included undifferentiated SCNs and those displaying commitment toward squamoid and ciliated glandular differentiation. Small, morphologically inconspicuous aggregates of p63-positive cells were commonly found in Hashimoto's thyroiditis. Commitment of p63-positive undifferentiated cells toward thyroid follicular epithelial differentiation was occasionally noted. One SCN variant, also associated with Hashimoto's thyroiditis, was a floretlike arrangement of p63-positive cells with fusiform nuclei. p63 staining was strong and uniform in some SCNs, but in other SCNs it was compartmentalized and homologous to stem cell-staining patterns in normal squamous or bronchial epithelia. Stem cell-like staining, associated with compartmentalized p63 staining or p63-positive undifferentiated cells, was noted in 7 of 27 papillary carcinomas. p63 immunostaining is a highly sensitive means of detecting SCNs. p63 expression patterns in SCNs and a subset of papillary carcinomas are closely homologous to stem cell-associated p63 staining patterns that have been described elsewhere in squamous and bronchial epithelia. We propose a stem-cell-associated model of papillary carcinoma oncogenesis that suggests that (1) p63-positive embryonal remnants rather than mature follicular cells are the cells of origin of a subset of papillary carcinomas; (2) these p63-positive cells are pluripotent and may stay undifferentiated or undergo benign squamoid or glandular maturation, may undergo thyroid follicular epithelial differentiation, may undergo oncogenic change leading to papillary carcinoma, or may trigger an immune reaction, resulting in lymphoid infiltration and Hashimoto's thyroiditis; and (3) Hashimoto's thyroiditis and papillary carcinoma may therefore be linked etiologically, because both disorders may be initiated by the same population of pluripotent p63-positive embryonal stem cell remnants.  相似文献   
102.
SUMMARY  Obstructive sleep apnoea (OSA), and snoring are associated with coronary heart disease. To assess whether OSA or snoring may contribute to this by raising fasting lipid or insulin levels, venous fasting total cholesterol, triglyceride, very-low-density lipoprotein, low-density lipoprotein, high-density lipoprotein, and insulin were measured in 15 untreated OSA patients and 18 snorers. Each of these subjects was individually matched to a control of the same sex, age ± 10%, body index ± 15%, smoking and drinking habits. This produced study groups which did not differ significantly by any of these criteria. Fasting venous blood samples were collected at 06.30 hours following polysomnography, and analysed blind of the subjects respiratory status. The OSA patients were then treated with nasal continuous positive airway pressure. In 10 of these subjects lipid and insulin levels were repeated after more than three months treatment. Lipid and insulin levels were also remeasured in the controls matched to these 10 subjects. The end points were compared with paired t -tests.
There was no difference in any of the end points when the untreated OSA patients and the snorers were compared to their matched controls ( P >0.25 for all comparisons), and none of the indices changed when OSA was corrected with nasal continuous positive airway pressure ( P > 0.25 for all comparisons).
Patients with obstructive sleep apnoea or snoring do not have significant fasting hyperlipidaemia or hyperinsulinaemia when compared to carefully matched controls. These factors are therefore unlikely to be the cause of the excess cardiovascular mortality experienced by this patient group.  相似文献   
103.
The correlation of p53 protein overexpression and the K-ras codon 12 mutatlon wlth histologlc type, grade of cytologic atypla, depth of lnvasion and other histologlc prognostic factors was studied In paraffin sectlons from 43 ductectatic-and 70 solid-type pancreatic ductal carcinomas. Overexpression of p53 was found in 23.3% (10143) of ductectatic carcinomas (17.2% of intraductal and 35.7% of lnvaslve carclnomas) and in 61.4% (43/70) of solid carcinomas. In ductectatic cancers, p53 overexpression was detected In 14.8% (4/27) of carcinomas wlth lowgrade atypla (CAL), 50.0% (5110) of carcinomas wlth high-grade atypla (CAH) and in 16.7% (In) of mixed low- and hlgh-grade cancers. In the last group, expression was restricted to an area of CAH. In solld cancers, p53 overexpression did not dlffer by histologic type or grade. Overexpresslon of p53 and K-ras mutatlons did not correlate with histologlc prognostic factors (lymphatic, venous and perineural Invasion, and lymph node metastasls) in ductectatlc and solld cancers or depth of invasion of solld carclnomas. Our data suggest that p53 alteratlon occurs at an early intraductal stage of solld carcinoma, irrespectlve of cellular atypla, but Is low in ductectatic CAL and becomes hlgher In ductectatlc CAH. K-ras mutatlon, present In a high percentage of tumors of all groups and not correlating with the factors above, showed no changes In frequency with tumor progression.  相似文献   
104.
磷脂双层膜稳定性的理论分析   总被引:2,自引:0,他引:2  
目的:越来越多磷脂双层膜的原子力显微镜扫描力谱显示溶液离子浓度对磷脂双层膜稳定性有很大影响,本文从理论角度研究溶液离子浓度对磷脂双层膜稳定性的影响,同时解释两个基于不同模型模拟结果差别的原因。方法:主要根据磷脂分子极性端带电特性,将极性端看作偶极子,然后基于偶极-偶极相互作用理论以及泊松-玻尔兹曼理论解决以上问题。结论:随着离子浓度的增加,磷脂双层膜趋于更加稳定;基于两个不同模型模拟结果差别的原因是高浓度溶液的强静电屏蔽作用。  相似文献   
105.
The practical realization of the concept of specific immunotherapy for systemic lupus erythematosus (SLE) has been hampered, thus far, by an inability to link DNA fragments to carrier protein. In this paper, a novel technique is described, in which glutaraldehyde is the linking agent. A 2-stage method was used to link oligonucleotides to a soluble protein carrier, such as keyhole limpet hemocyanin (KLH) or human gamma globulin (HGG), whereas a 1-stage technique was sufficient to link oligonucleotides to sheep red cells. Both the ultraviolet absorbance spectrum and diphenylamine assay demonstrated that oligonucleotides were coupled to soluble protein. The conjugate of oligonucleotide to protein carrier appears to be recognized by anti-DNA antibody since oligonucleotide linked to either KLH or HGG inhibited the binding of anti-DNA antibody in vitro, and oligonucleotide-coupled sheep cells are agglutinating by seropositve sera from lupus patients. In addition, oligonucleotide-KLH raised hemagglutinating antibody to denatured DNA in C57BL/6, DBA/2 or NZB mice, as well as IgG antibody as detected by SPRIA in C57BL/6 and DBA/2 mice. The significance of this new method for the development of an antigen specific therapy of SLE is discussed.  相似文献   
106.
Interventions aimed at decreased exposure of children to known atherosclerosis risk factors may have untoward behavioral side effects. We examined how children’s behavior or parent’s perception of the behavior of the children at 3 years of age was influenced by the intervention in a prospective randomized trial that began in infancy and effectively decreased scrum cholesterol concentration. This Special Turku coronary Risk factor Intervention Project for babies (STRIP) began when the infant was 7 months old. Half of 1.062 children received individualized dietary counseling at 1-to 3-month intervals during the first 2 years of age and then half-yearly; the other half had an unrestricted diet. At 3 years of age a standardized questionnaire of the child’s behavior was sent to 791 families (76% returned the questionnaire). At the onset of the trial the sociodemographic data of the families and scrum lipid values of the intervention and control children were similar. Later, mean serum cholesterol values of the intervention children remained constantly at a level 6% to 10% below the values of the control children. At 3 years of age the parental perceptions of the child’s behavior suggested minimal differences between the intervention and control children. The intervention children were slightly less jealous and more active and creative, but showed slightly more negative signs of behavior (bed-wetting, problems in falling asleep, fears) than the controls. We conclude that long-term, individualized dietary and lifestyle intervention that begins in infancy slightly influences children’s behavior or parent’s recognition of the behavior of the children at the age of 3 years. This work was supported in part by grants from the Varsinais-Suomi Regional Fund of the Finnish Cultural Foundation, the Mannerheim League for Child Welfare, the Academy of Finland, and the Alli Paasikivi Foundation.  相似文献   
107.
目的观察不同剂量阿托伐他汀对急性冠脉综合征(ACS)患者外周血中总胆固醇(TC)、高敏C反应蛋白(hs-CRP)、白细胞介素-6(IL-6)、血栓素B2(TXB2)、血小板颗粒膜蛋白-140(GMP-140)、血浆纤溶酶原激活剂抑制物-1(PAI-1)水平及血浆组织型纤溶酶原激活剂(t-PA)活性的影响。探讨阿托伐他汀对ACS防治的可能机制及不同剂量阿托伐他汀的安全性。方法ACS患者65例,在拜阿斯匹林、氯吡格雷等基础治疗外随机分为三组,分别给予阿托伐他汀10mg/d、20mg/d、40mg/d睡前服用。入院第1天、第14天分别抽取空腹静脉血16ml。测定hs-CRP、IL-6、TXB2、GMP-140、t-PA、PAI-1及TC、天冬氨酸转氨酶(AST)、丙氨酸转氨酶(ALT)、肌酸激酶(CK)。采用SPSS13.0统计软件对检测结果的组间及治疗前后进行比较。结果三组TC、hs-CRP、IL-6、TXB2、GMP-140、PAI-1治疗后均有下降、t-PA活性上升,治疗后三组间比较亦有差异;而三组治疗前后CK、ALT、AST组间无显著差异,治疗后无显著上升,以上结果均有统计学意义。结论阿托伐他汀对ACS患者血脂及炎症反应、血小板活性、纤溶活性有积极作用,并在一定范围内随着剂量的增加而加强,同时具有良好的安全性。  相似文献   
108.
Aim: Hormone‐sensitive lipase (HSL) has been proposed to regulate triacylglycerol (TG) breakdown in skeletal muscle. In muscles with different fibre type compositions the influence on HSL of two major stimuli causing TG mobilization was studied. Methods: Incubated soleus and extensor digitorum longus (EDL) muscles from 70 g rats were stimulated by adrenaline (5.5 μm , 6 min) or contractions (200 ms tetani, 1 Hz, 1 min) in maximally effective doses or by both adrenaline and contractions. Results: Hormone‐sensitive lipase activity was increased significantly by adrenaline as well as contractions, and the highest activity (P < 0.05) was seen with combined stimulation [Soleus: 0.40 ± 0.03 (SE) m‐unit mg protein?1 (basal), 0.65 ± 0.02 (adrenaline), 0.65 ± 0.03 (contractions), 0.78 ± 0.03 (adrenaline and contractions); EDL: 0.18 ± 0.01, 0.30 ± 0.02, 0.26 ± 0.02, 0.32 ± 0.01]. Glycogen phosphorylase activity was always increased more by adrenaline compared with contractions [Soleus: 60 ± 4 (a/a + b)% vs. 46 ± 3 (P < 0.05); EDL: 60 ± 5 vs. 39 ± 6 (P < 0.05)]. After combined stimulation glycogen phosphorylase activity in soleus [59 ± 3 (a/a + b)%] was identical to and in EDL [45 ± 4 (a/a + b)%] smaller (P < 0.05) than the activity after adrenaline only. Conclusions: In slow‐twitch oxidative as well as in fast‐twitch glycolytic muscle HSL is activated by both adrenaline and contractions. These stimuli are partially additive indicating at least partly different mechanisms of action. Contractions may impair the enhancing effect of adrenaline on glycogen phosphorylase activity in muscle.  相似文献   
109.
Biopsies from the common bile ducts from seven patients undergoing surgery for biliary obstruction due to stones or malignancy were studied histochemically and electron microscopically. The surface of the bile duct is lined by a tall epithelium which extends into diverticula. Apically, they contain some neutral and sialated mucosubstances. Fucosyl residues were found in the Golgi apparatus and along the apical cell membrane. The latter is lined by microvilli. There was a well-developed rough endoplasmic reticulum and Golgi apparatus and a small number of apical secretory droplets. Large numbers of lipid droplets were present basally in some cells. Lipid-containing macrophages were also seen intra-epithelially and in the lamina propria. This suggests a possible pathway for lipid transport. The glands were lined by cuboidal cells, some containing much mucus--sulphated, sialated, and neutral with a basal nucleus. A well-developed endoplasmic reticulum and Golgi apparatus were found with abundant secretory droplets. The glandular epithelium contained lysozyme, alpha-1-antitrypsin, and alpha-1-antichymotrypsin. These may play a protective role. The lamina propria contained scattered smooth muscle cells amongst the fibroblasts and inflammatory cells.  相似文献   
110.
After bone marrow (BM) or solid-organ (SO) transplantation viremic Cytomegalovirus (CMV) infection is observed frequently. Quantitative assay of CMV in blood helps the management of this clinical condition. In the present report, 83 samples from 39 solid organ recipients, three CMV assays were compared simultaneously for the first time: the Nuclisens CMV pp67 assay (nucleic acid sequence-based amplification, NASBA), an "in-house" quantitative real-time PCR assay (TaqMan) for CMV DNA, and pp65 antigenemia. The relation between CMV DNA and pp65 antigenemia, the quantitative assays, was evaluated on a larger group including 251 blood samples from 118 solid organ recipients. Real-time PCR provided the best results; > or =130 CMV DNA copies/2 x 10(5) peripheral blood leukocytes (PBLs) predicted > or =1 pp65 antigen positive (Ag+) cell/2 x 10(5) PBLs. By taking pp65 antigenemia as the "gold standard," the sensitivity of CMV DNA quantitation and of the pp67 RNA assay were 0.95 and 0.20, respectively, while the corresponding specificity values were 0.50 and 0.93. When real-time PCR was considered as the "gold standard," the sensitivity and specificity of the pp65 antigenemia were 0.65 and 0.91, respectively. Among the three tests examined, the sensitivity of the pp67 RNA assay was the lowest. On the other hand, the pp67 RNA assay was highly specific and effective in pinpointing high viremia patients. The present report, by providing predictive values for all three diagnostic profiles, DNA load, antigenemia, and pp67RNA, is a contribution for validation of real-time PCR as a new standard for quantitative assessment of CMV viremia in clinical settings.  相似文献   
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