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181.
颅底胆脂瘤的MRI特征 总被引:8,自引:0,他引:8
目的探讨颅底胆脂瘤MRI分型的意义及其MRI诊断特征。方法观察15例颅底胆脂瘤的CT、MRI与病理学资料,根据肿瘤T1WI信号的不同,将颅底胆脂瘤分为Ⅰ型和Ⅱ型,分析两型胆脂瘤在CT、MRI征象和颅底骨质侵犯等方面的差异。结果15例颅底胆脂瘤T2WI显著高信号,肿瘤实质无强化。15例中,Ⅰ型,6例,肿瘤位于桥前池和桥小脑角区,CT均匀低密度,T1WI均匀低信号,包膜不强化,颅底骨质改变轻微,肿瘤实质为胆固醇结晶;Ⅱ型,9例,肿瘤位于一侧中、后颅窝底,CT呈混杂密度,T1WI呈混杂信号,其中4例为低信号中夹杂少量高信号,另5例以高信号为主,包膜强化,颅底骨质呈显著外压性改变,肿瘤实质为角化上皮和蛋白。结论颅底胆脂瘤分为Ⅰ型和Ⅱ型是合理的,体现了两型颅底胆脂瘤组织病理和生物学行为的差异,对指导MRI诊断有积极意义。T1WI信号多样性、T1WI显著高信号、肿瘤实质不强化以及与MRI分型相关的颅底骨质侵犯是颅底胆脂瘤的MRI诊断特征。 相似文献
182.
183.
Bošnjaković Petar Ivković Tomislav Ilić Miodrag Aracki Snežana 《Cardiovascular and interventional radiology》1992,15(4):217-220
Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment
of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using
retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual
stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning.
We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to
PTA. 相似文献
184.
185.
凝血因子Ⅷ(FⅧ)由vWF和FⅧ:C组成。FⅧ:C的合成部位至今尚未确认。本文检测了16~22周胎龄胎儿肝、脾、肾及肾小球组织中Ⅷ:C活性及vWF:Ag含量后,发现肾中Ⅷ:C活性较高(1.679±1.588 U/ml),尤其是肾小球中高达46.313±40.651U/ml,脾中次之(0.372±0.462 U/ml),肝中最低(0.021±0.029U/ml)。将3种组织细胞培养后,发现仍以肾中Ⅷ:C活性最高。由此提示,肾可能是Ⅷ:C的合成部位。同时检测三器官中vWF:Ag,发现含量极微。这些组织中Ⅷ:C与vWF的关系有待研究。 相似文献
186.
采用反相高效液相色谱法,以0.02mol/L硼砂为流动相,YNG C_(16)H_(37),为固定相,检测波长288nm,测定隐形眼镜保护药水中EDTA二钠和山梨酸钾的含量。简便快速,结果准确可靠。回收率100.26%(EDTA)、100.36%(山梨酸钾)。相对标准偏差0.85%(EDTA)、0.41%(山梨酸钾)。 相似文献
187.
中医药抗消化性溃疡复发的研究 总被引:7,自引:0,他引:7
总结了运用中医药疗法对68例消化性溃疡愈合后的患者追踪观察2~4年的临床疗效,显示其具有复发率低的优势;又根据消化性溃疡发生及复发的机制分析了所采用的预防性治疗措施的作用机理;还对溃疡病复发的一些相关问题作了简单论述。 相似文献
188.
Guan Xinmin Zhang Jian Shi Bo** Ouyang Xingbiao Research Department of Acupuncture Anesthesia Mechanism & Department of Neurobiology Tongji Medical University Wuhan China Department of Physiology Jinzhou School of Health Jinzhou Liaoning Province China 《世界针灸杂志》1993,(1)
For investigating the effect of acupuncture on ischemic arrhythmia and its mech-anism, adult albino rats with ligated anterior descending branch of coronary artery as experimentalmodel were treated with or without acupuncture, and others with imitative operation but without bothcoronary artery ligation and acupuncture treatment were used as control. It was found in acupuncturegroup that the fibrillation-liability of ischemic myocardium was efficiently decreased, the affinity ofAch-M receptors on membranes of ischemic myocardium was markedly increased, and the tolerance ofischemic myocardium to atropine was elevated in the experiment of atropine inducing fibrillation.These results indicate that acupuncture may play a therapeutic role on ischemic arrhythmia throughactivating the activity of muscarine-like receptors of cholinergic nervous system. 相似文献
189.
Cécile Viboud Pierre-Yves Bo?lle Simon Cauchemez Audrey Lavenu Alain-Jacques Valleron Antoine Flahault Fabrice Carrat 《The British journal of general practice》2004,54(506):684-689
BACKGROUND: Influenza transmission in households is a subject of renewed interest, as the vaccination of children is currently under debate and antiviral treatments have been approved for prophylactic use. AIMS: To quantify the risk factors of influenza transmission in households. DESIGN OF STUDY: A prospective study conducted during the 1999 to 2000 winter season in France. SETTING: Nine hundred and forty-six households where a member, the index patient, had visited their general practitioner (GP) because of an influenza-like illness were enrolled in the study. Five hundred and ten of the index patients tested positive for influenza A (subtype H3N2). A standardised daily questionnaire allowed for identification of secondary cases of influenza among their household contacts, who were followed-up for 15 days. Of the 395 (77%) households that completed the questionnaire, we selected 279 where no additional cases had occurred on the day of the index patient's visit to the GP. METHODS: Secondary cases of influenza were those household contacts who had developed clinical influenza within 5 days of the disease onset in the index patient. Hazard ratios for individual clinical and demographic characteristics of the contact and their index patient were derived from a Cox regression model. RESULTS: Overall in the 279 households, 131 (24.1%) secondary cases occurred among the 543 household contacts. There was an increased risk of influenza transmission in preschool contacts (hazard ratio [HR] = 1.85, 95% confidence interval [CI] = 1.09 to 3.26) as compared with school-age and adult contacts. There was also an increased risk in contacts exposed to preschool index patients (HR = 1.93, 95% CI = 1.09 to 3.42) and school-age index patients (HR = 1.68, 95% CI = 1.07 to 2.65), compared with those exposed to adult index cases. No other factor was associated with transmission of the disease. CONCLUSION: Our results support the major role of children in the dissemination of influenza in households. Vaccination of children or prophylaxis with neuraminidase inhibitors would prevent, respectively, 32-38% and 21-41% of secondary cases caused by exposure to a sick child in the household. 相似文献
190.