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Smith  R; Rosen  JM; Alderson  PO 《Radiology》1986,158(1):63-66
The preoperative cholescintigrams of 16 patients with subacute or chronic gallbladder (GB) perforation demonstrated at surgery were reviewed, and the scintigraphic findings were characterized. Persistent GB nonvisualization was found in each study. Additional findings included a band of increased pericholecystic hepatic activity (PCHA) (n = 7) and/or a photopenic region in the GB fossa (n = 7). PCHA and photopenic region findings, when visualized, were most commonly associated with a subacute localized perforation with pericholecystic abscess formation. However, the sensitivity of each of these findings was only 44%. Cholescintigrams did not directly demonstrate the perforation site in any patient. Although the presence of the PCHA sign and/or GB fossa photopenic region appears to identify a subgroup of patients at increased risk for perforation, cholescintigraphy is relatively insensitive for detection of subacute or chronic GB perforation.  相似文献   
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The stability of betamethasone-17-valerate in semi-solid bases has been investigated. Emphasis has been placed on the stability problems which could arise upon dilution of proprietary preparations by the use of model systems. Betamethasone-17-valerate has been shown to decompose to betamethasone-21-valerate and betamethasone alcohol. Quantitation of the decomposition was by direct densitometry on thin layer chromatographic plates. The decomposition was found to be an apparent first order process and to depend on the diluent used and its concentration. Attempts were also made to relate the rate of decomposition to the pH of the base used, and to stabilize the products.  相似文献   
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Smith  R; Rosen  JM; Gallo  LN; Alderson  PO 《Radiology》1985,156(3):797-800
Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation.  相似文献   
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抽取了北京市丰台区7家民营医院,采用定性访谈和问卷调查方式,分析了民营医院自身的优势、存在的问题以及面临的制约因素,提出了完善职称晋升、医保定点及税收政策,加强与民营医院的沟通,加强对民营医院的监管等措施,为如何更好地引入社会资本提供参考建议。  相似文献   
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Eleven cases of migraine with and without aura were investigated with positron emission tomography (PET). Regional cerebral blood flow (rCBF), oxygen metabolism (rCMRO2) and oxygen extraction (rOER) were measured during baseline ( n =11), aura ( n = 6), headache ( n = 10) and after treatment with sumatriptan ( n = 4). Data were analysed using and ROI-based approach from 26 different anatomically defined regions, and also an exploratory approach whereby all subjects were normalized to a stereotactic brain atlas; t -maps were constructed by depicting significant changes between states. The exploratory approach revealed a region corresponding to the primary visual cortex with significant reductions in rCBF (23.1%) and rCMRO2 (22.5%), but no change in rOER during the headache phase compared to baseline. These data suggest that cerebral ischemia was not the primary cause of the attacks in these cases.  相似文献   
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应用5-氨基-γ-酮戊酸(ALA)诱导的卟啉荧光诊断(FDAP)中,肉眼可观察到原卟啉IX(PpIX)沉积。因操作重复性低,且涉及PpIX肿瘤选择的机制知之甚少,所以解释荧光数据仍有些困难。本研究中,作者要研究FDAP后银屑病和日光性角化病(AK)患者皮损的PpIX沉积情况。基于此目的,将患者脱屑区皮损和无皮损正常皮肤用20%ALA油孵育3h,进行FDAP,取强荧光区皮损和无皮损处皮肤活检。从活检标本中提取PpIX、蛋白质和双链DNA行荧光分光光度法定量,用图像分析软件分析由FDAP获得的数字图像。  相似文献   
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