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排序方式: 共有5534条查询结果,搜索用时 15 毫秒
31.
目的:分析并总结我院收治的自身免疫性胰腺炎( AIP)临床特征及诊治经验。方法回顾性分析2009年至2013年我院收治的13例AIP的临床资料。结果13例AIP中,中位年龄48岁,临床表现主要为上腹疼痛不适,梗阻性黄疸及体重下降。胰腺弥漫性增大及局限性增大各6例,胰体尾假性囊肿及胰腺结石各1例,胰管扩张4例。胰腺外器官受累9例(胆管病变8例、胆囊病变7例、腹膜后纤维化1例、腹腔淋巴结肿大6例、脾静脉变细4例、干燥综合征及溃疡性结肠炎各1例)。7例行血免疫标志物检查,IgG升高5例,类风湿因子( RF)及抗核抗体( ANA)升高各3例。8例被误诊而行手术治疗。经激素治疗后,患者预后良好。结论 AIP是一种少见的自身免疫性疾病,无特异临床表现,易与胰腺癌及胆管癌混淆,误诊率高。必须充分认识和重视AlP的诊治,避免因误诊而行不必要的手术治疗。  相似文献   
32.
The aim of the present study was to evaluate the effect of brushing with two whitening dentifrices (Colgate Optic White (COW) and Colgate Optic White Charcoal (COC)) on surface gloss, micro-roughness, and micro-hardness of nanostructured hybrid conventional (Z350) and bulk-fill (Tetric N Ceram bulk-fill) polymer composite. In total, 96 disk samples using two nano-hybrid composite polymers (Z350 and Tetric N Ceram Bulk-fill) were prepared. All specimens were exposed to two different dentifrices (COW and COC), resulting in four main subgroups in the study. Specimens were assessed for surface gloss, micro-roughness (Ra), and micro-hardness using standardized methodology. Means and standard deviations of properties compared using paired t-test, one-way and two-way ANOVA, and post hoc test. The presence of dentifrices did not show any significant difference in micro-hardness values of Z350 (p > 0.05), whereas micro-hardness of bulk-fill composite significantly reduced on dentifrices exposure (p ≤ 0.05). Bulk-fill polymer composite showed significant reduction in gloss after dentifrice exposure (p < 0.05), however, Z350 showed no significant loss of gloss due to dentifrices (p > 0.05). A significant increase in Ra was observed for both resin materials after exposure to dentifrices (COC and COW). Conventional resin composite (Z350) showed comparable surface hardness and gloss before and after dentifrice exposure, however, micro-roughness increased significantly due to dentifrice exposure. Bulk-fill resin (Tetric N Ceram) showed significant loss of micro-hardness and gloss and increase in micro-roughness on dentifrice exposure. Conventional nano-hybrid composite polymer showed better durability in resisting loss of surface properties compared to bulk-fill resin polymer in the present experiment.  相似文献   
33.
ObjectivesTo evaluate the dental arch changes produced by the miniscrew-supported palatal crib (MSPC) and the conventional fixed palatal crib (CFPC) after the treatment of patients with anterior open bite (AOB) attributed to the tongue-thrusting habit in the mixed dentition stage.Materials and MethodsA total of 26 children aged 8 to 11 years with an AOB were randomly distributed into two equal groups; the MSPC group was treated using a palatal crib supported by two miniscrews inserted paramedially, whereas the CFPC group was treated using a conventional fixed palatal crib soldered to bands. Digital models were obtained pretreatment and after a follow-up duration of 9 months.ResultsThe MSPC group included 12 participants (9 girls and 3 boys; mean age, 9.4 ± 0.75 years), and the CFPC group included 12 participants (10 girls and 2 boys; mean age, 9.0 ± 0.73 years). The amount of AOB closure was similar in both groups: 3.97 ± 1.44 mm in the MSPC group and 3.97 ± 0.89 mm in the CFPC group. There was significant mesial movement of the maxillary first molar in the CFPC (−1.42 ± 0.99 mm) compared with the MSPC group (−0.53 ± 0.32 mm).ConclusionsBoth appliances resulted in similar improvement in the amount of AOB closure. There was significantly more mesial movement of the maxillary first molars in the CFPC group compared with the MSPC group.  相似文献   
34.
Interstitial pneumonia (IP) is a major risk factor for lung adenocarcinoma (LADC). IP-related LADC predominantly develops in the bronchiolar metaplasia lining in honeycomb lesions. Kirsten rat sarcoma virus (KRAS) is the most common oncogene mutated in IP-related LADC. The present study examined the metaplastic epithelia in honeycomb lesions for KRAS mutations using digital droplet polymerase chain reaction (ddPCR), a sensitive method used to detect infrequent mutations. Significantly higher KRAS mutation variant allele frequencies (VAFs) were detected in the metaplastic lung epithelia from 13 patients with IP compared with those in 46 non-lesioned lung samples from patients without IP (G12V, P=0.0004, G12C, P=0.0181, and G12A, P=0.0234; Mann Whitney U test). Multivariate analyses revealed that higher KRAS G12V (logistic regression model; P=0.0133, odds ratio=7.11) and G12C (P=0.0191, odds ratio=5.81) VAFs in patients with IP were independent of confounding variables, such as smoking and age. In patients with IP, metaplastic epithelia exhibited significantly higher KRAS G12V and G12C VAFs compared with the non-lesioned counterparts (paired t-test; G12V, P=0.0158, G12C, P=0.0465). These results suggested that IP could increase KRAS mutations and supported the hypothesis that bronchiolar metaplasia could be a precursor for IP-related LADC.  相似文献   
35.
抗性淀粉测定方法的研究进展   总被引:10,自引:0,他引:10  
石劢  徐贵发 《卫生研究》2005,34(4):504-507
系统而简要介绍了抗性淀粉测定方法的国内外研究现状与发展趋势,通过与回肠流出物中抗性淀粉的测定数据比较,选取最接近人体摄入情况的体外检测方法,对常见食物中的抗性淀粉进行定量,为研究人体抗性淀粉实际摄入状况提供非常重要的依据。  相似文献   
36.
Some novel imine metal chelates with Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, and Cd2+ cations were produced from 2-acetylferrocene and 3-aminophenol. The new acetylferrocene azomethine ligand ((Z)-cyclopenta-1,3-dien-1-yl(2-(1-((3-hydroxyphenyl)imino)ethyl)cyclopenta-2,4-dien-1-yl)iron) and its metal ion chelates were constructed and elucidated using FT-IR, UV/Vis, 1HNMR, DTA/TGA, CHNClM studies, mass spectrometry and SEM analysis. According to the TGA/DTG investigation, the ferrocene moiety spontaneously disintegrates to liberate FeO. The morphology of the free acetylferrocene azomethine via SEM analysis was net-shaped with a size of 64.73 nm, which differed in Cd(II) complex to be a spongy shape with a size of 42.43 nm. The quantum chemical features of the azomethine ligand (HL) were computed, and its electronic and molecular structure was refined theoretically. The investigated acetylferrocene imine ligand behaves as bidinetate ligand towards the cations under study to form octahedral geometries in case of all complexes except in case of Zn2+ is tetrahedral. Various microorganisms were used to investigate the anti-pathogenic effects of the free acetylferrocene azomethine ligand and its metal chelates. Moreover, the prepared ligand and its metal complexes were tested for anticancer activity utilizing four different concentrations against the human breast cancer cell line (MCF7) and the normal melanocyte cell line (HBF4). Furthermore, the binding of 3-aminophenol, 2-acetylferrocene, HL, Mn2+, Cu2+, and Cd2+ metal chelates to the receptor of breast cancer mutant oxidoreductase was discovered using molecular docking (PDB ID: 3HB5).  相似文献   
37.
Neuroimaging studies suggest that the right dorsolateral prefrontal cortex (rDLPFC) is an important brain area involved in fairness-related decision-making. In the present study, we used transcranial direct current stimulation (tDCS) over the rDLPFC to investigate the effects of changed cortical excitability on fairness norm enforcement in social decision-making. Participants received anodal, cathodal or sham stimulation before performing a modified ultimatum game task, in which participants were asked to accept or reject the proposer’s offer and self-rate the intensity of their anger at offers on a 7-point scale. The results showed that the rejection rate of unfair offers and anger level were higher in the anodal compared to the sham and cathodal groups and that the level of anger at unfair offers can predict the rejection rate. Furthermore, the fairness effect of RTs was more prominent in the anodal group than in the sham and cathodal groups. Our findings validate the causal role of the rDLPFC in fairness-related decision-making through tDCS, suggesting that strengthening the rDLPFC increases individuals’ reciprocal fairness in social decision-making, both in subjective rating and behaviors.  相似文献   
38.
目的探讨睾丸小细胞神经内分泌癌的临床病理特征和生物学行为。方法回顾分析睾丸小细胞神经内分泌癌1例并复习有关文献予以讨论。结果患者术前未得到明确的病理诊断,术后2周恢复良好,痊愈出院。出院3周后右腋窝淋巴结转移,7周后全身转移死亡。病理检查:肿瘤细胞表达神经内分泌标记物神经原特异性烯醇酶、嗜铬粒蛋白A和突触素。结论睾丸小细胞神经内分泌癌是一种比较少见的高度恶性肿瘤,有独特的病理形态,早期即可发生转移,预后凶险,死亡率高。  相似文献   
39.
We evaluated a 39-year-old pregnant woman with right temporal lobe epilepsy. During the second trimester, seizure deterioration was responsive to an increased daily dose of levetiracetam (LEV). However, immediately after delivery, new non-habitual seizures emerged along with a sharply increased LEV concentration. The frequency of habitual seizures also slightly increased. The non-habitual seizures completely disappeared, and the frequency of the habitual seizures improved to the baseline level after the LEV dosage was reduced. Thus, a paradoxical effect of an increased LEV blood concentration was assumed to be a potential cause of these events. Peripartum pharmacokinetic fluctuations in LEV levels should be monitored carefully.  相似文献   
40.
People with asthma suffer from impaired health-related quality of life (HRQL), but the determinants of HRQL among asthmatics are not completely understood. The aim of this investigation was to study determinants of low HRQL in asthmatics and to study whether the determinants of HRQL differ between sexes and age groups. A cohort of three age groups in Sweden was investigated in 1990 using a questionnaire with focus on respiratory symptoms. To study quality of life, the generic instrument Gothenburg Quality of Life was used. The participants were also investigated with interviews, spirometry, and allergy testing. Asthma was diagnosed in 616 subjects. Fifty-eight per cent (n = 359) of the subjects were women; and 24% were smokers, 22% ex-smokers, and 54% were non-smokers. Women were more likely than men to report poor health-related quality of life. Respiratory symptoms severity was another independent determinant of a lower quality of life as well as airway responsiveness to irritants. Current and former smokers also reported lower quality of life. Finally, absenteeism from school and work was associated with lower quality of life. Factors such as sex, smoking habits, airway responsiveness to irritants, respiratory symptom severity, allergy, and absenteeism from school and work were associated with low HRQL in asthmatics.  相似文献   
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