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51.
α1-Adrenoceptors mediate contraction of iris dilator smooth muscle and hence pupil dilatation. We compared the ability of i.v. bolus injections of alfuzosin, doxazosin, naftopidil, prazosin, tamsulosin and terazosin to antagonise phenylephrine-induced mydriasis relative to their potency for inhibiting phenylephrine-induced elevations of intraurethral pressure (IUP) in rabbits. Moreover, we compared the ability of these drugs to induce miosis in conscious rabbits in the absence of phenylephrine. All antagonists inhibited the effects of phenylephrine on pupil size and IUP, and the ratio of the respective ED50 values was close to unity in all cases. The doses required to induce statistically significant miosis in the absence of phenylephrine were 30- to 100-fold higher than those inhibiting phenylephrine-induced mydriasis for all antagonists, except for naftopidil. Moreover, the miotic effects of all α1-adrenoceptor antagonists were fully reversible within 8 h. We conclude that alfuzosin, doxazosin, naftopidil, prazosin, tamsulosin and terazosin inhibit phenylephrine-induced mydriasis in the same dose range as they inhibit elevations in IUP. Higher doses of all antagonists are required to induce miosis in the absence of an exogenous agonist, and such miosis is always reversible within hours.  相似文献   
52.
目的观察清脂软胶囊对实验性小鼠记忆障碍的改善作用。方法采用小鼠双侧颈动脉结扎8min后再灌注,造成小鼠血管性痴呆模型,形成记忆障碍;以亚硝酸钠皮下注射建立小鼠学习记忆障碍模型;用跳台法、Y-型迷宫法观察清脂软胶囊对记忆障碍模型小鼠的影响。结果与假手术组比较,血管型痴呆模型组小鼠由于脑缺血而形成神经损伤,小鼠跳台实验的下台潜伏期明显缩短(P〈0.01),5min内错误次数明显增多(P〈0.01),Y型迷宫(空间分辨能力)正确次数明显下降(P〈0.01),说明脑缺血再灌注后可影响动物的记忆功能。与脑缺血再灌注损伤记忆障碍模型组比较,清脂软胶囊大、中、小剂量组均可显著延长首次出现错误的潜伏期。减少5min内小鼠出现的错误次数,增加Y型迷宫空间分辨的正确次数。在化学试剂引发的记忆障碍模型中,与正常对照组比较,亚硝酸钠小鼠首次出现错误的潜伏期明显缩短,5min内错误次数显著增加(P〈0.05),说明亚硝酸钠可致小鼠记忆功能障碍。与亚硝酸钠模型组相比,清脂软胶囊大、中、小剂量组均可明显延长首次出现错误的潜伏期,减少5min内小鼠出现的错误次数。小鼠脑组织中乙酰胆碱酯酶活性研究表明,清脂软胶囊可显著降低记忆障碍模型小鼠脑组织中乙酰胆碱酯酶活性。结论清脂软胶囊对实验性小鼠记忆障碍有显著的改善作用,这种作用可能与降低脑组织内乙酰胆碱酯酶活性相关。  相似文献   
53.
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   
54.
患儿男,1月龄,因“反复腹泻20+ d,吐奶4 d”入院。患儿生后第8天开始出现反复顽固性腹泻,伴腹胀、呕吐、脱水、酸中毒、营养不良,家族中多例消化系统恶性肿瘤患者。基因检测发现人上皮黏附因子(epithelial cell adhesion molecule, EpCAM)基因复合杂合突变(c.491+1G>A;c.352_353ins CACC),确诊为先天性簇绒肠病。予部分肠外营养支持,患儿腹泻好转,但加奶困难,奶量增加即腹胀、呕吐。住院后期出现反复发热,最终家属签字出院。出院后仍有腹泻、吐奶,出院4周患儿体质量下降约1 kg,最终死亡。  相似文献   
55.
血管内皮祖细胞靶向损伤血管内皮磁共振成像的实验研究   总被引:2,自引:0,他引:2  
Ma ZL  Teng GJ  Mai XL  Ju SH  Deng G  Sun JH  Zhang HY  Yu H  Li GZ 《中华医学杂志》2007,87(10):679-684
目的采用超顺磁性氧化铁(sPIO)作为磁共振示踪细胞的标记物,为血管内皮祖细胞移植防治血管内皮损伤性疾病提供实验依据。方法分离、鉴定并培养新西兰大白兔外周血血管内皮祖细胞(EPCs),制备Fe2O3^-多聚左旋赖氨酸(PIJL)并体外标记EPCs。用2.5F球囊扩张兔右侧颈动脉,制作血管内膜损伤模型,进行EPCs局部移植。A组5只,移植Fe2O3-PLL标记的EPCs,B组5只,移植荧光标记的EPCs,C组5只为空白对照,局部注射生理盐水。细胞移植后7d,所有实验兔行MR颈动脉扫描,并取受损伤血管做病理组织学检查,并与MR信号变化进行对比分析。结果EPCs的Fe2O3^-PLL标记率〉95%,A组标记细胞移植后7d,MR扫描T2WI显示损伤血管壁明显低信号区,而B组和C组无明显异常信号改变;病理学检测显示A组损伤血管内膜有普鲁氏蓝染色阳性细胞黏附,B组损伤血管内皮有强荧光表达,C组损伤血管内皮无表达。结论利用1.5TMR仪进行活体成像技术,可示踪并检测磁粒子标记血管内皮祖细胞在损伤血管内皮的归巢、黏附及分布,为血管内皮祖细胞移植防治血管内皮损伤性疾病提供了实验依据。  相似文献   
56.
目的 观察肌内效贴治疗对脑卒中后肩手综合征(SHS)患者上肢静脉的影响.方法 选择脑卒中后并发SHS患者50例,随机分为观察组及对照组各25例.两组患者均采用常规治疗,观察组在常规治疗的基础上配合肌内效贴治疗.采用彩色多普勒超声检测两组治疗前后后肘正中静脉的血管内径、血管壁厚度及最大血流速度,并观察患肢静脉频谱图和血管二维声像图的变化.结果 治疗后,彩色多普勒超声检测可见患者血管走行恢复平直,静脉瓣活动柔软,随心动周期、呼吸周期变化可见不同程度的起伏.观察组静脉血管内径均较治疗前缩小,静脉回流速度提升(P<0.05),但对照组治疗前后比较差异无统计学意义(P>0.05);与对照组比较,治疗后观察组静脉血管内径较小,静脉回流速度较快(P<0.05).结论 肌内效贴能明显增加上肢静脉血流量,加快局部血流的速度,促进静脉回流,从而缓解疼痛消除水肿,有利于患肢的神经营养和功能改善.  相似文献   
57.
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   
58.
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   
59.
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   
60.
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   
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