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Progressive increase of the serum pH upon standing and storage in different conditions is documented. Bilirubin albumin titration studies were performed on serum of different pH by Sephadex gel filtration and horseradish peroxidase oxidation methods. Results showed that different pH produced different titration curves and that more reproducible and consistent results were obtained with the peroxidase oxidation titration method. Addition of HC1 and CO2 to the serum also produced different bilirubin-protein titration results. For blirubin albumin binding studies, we suggest to adjust the pH to 7.4 with CO2 to obtain clinically meaningful data.  相似文献   
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[11C]UCB-J PET for synaptic vesicle glycoprotein 2 A (SV2A) has been proposed as a suitable marker for synaptic density in Alzheimer’s disease (AD). We compared [11C]UCB-J binding for synaptic density and [18F]FDG uptake for metabolism (correlated with neuronal activity) in 14 AD and 11 cognitively normal (CN) participants. We assessed both absolute and relative outcome measures in brain regions of interest, i.e., K1 or R1 for [11C]UCB-J perfusion, VT (volume of distribution) or DVR to cerebellum for [11C]UCB-J binding to SV2A; and Ki or KiR to cerebellum for [18F]FDG metabolism. [11C]UCB-J binding and [18F]FDG metabolism showed a similar magnitude of reduction in the medial temporal lobe of AD –compared to CN participants. However, the magnitude of reduction of [11C]UCB-J binding in neocortical regions was less than that observed with [18F]FDG metabolism. Inter-tracer correlations were also higher in the medial temporal regions between synaptic density and metabolism, with lower correlations in neocortical regions. [11C]UCB-J perfusion showed a similar pattern to [18F]FDG metabolism, with high inter-tracer regional correlations. In summary, we conducted the first in vivo PET imaging of synaptic density and metabolism in the same AD participants and reported a concordant reduction in medial temporal regions but a discordant reduction in neocortical regions.  相似文献   
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New sonographic imaging observations in focal pancreatitis   总被引:4,自引:0,他引:4  
The imaging findings that ultrasonographically differentiate focal acute pancreatitis (FAP) from a malignant lesion of the pancreas are described. Focal acute pancreatitis is ultrasonographically (US) characterized as a hypoechoic, homogeneous, localized, subsegmental, non-expansive and diffusely demarcated lesion located mostly in the head of the pancreas. It could not be visualized using CT. Endoscopic retrograde cholangiopancreatography (ERCP) performed in 13 of the 32 patients, showed chronic pancreatitis. Focal acute pancreatitis disappeared in 1–6 months at US follow-up. The clinical diagnoses were acute pancreatitis in 11 patients, chronic pancreatitis in 12 patients, biliary disease in 5 patients, hepatopathia in 1 patient while the diagnosis was unknown in 2 patients. No patient developed any pancreatic cancer during a median of 85 months of follow-up. In conclusion, the present data indicate that patients with FAP at US, without any focal lesion seen on either CT or ERCP, have a benign pancreatic lesion, which resolves in 1–6 months; thus, such patients probably do not need any further investigation or follow-up at all. Received: 9 February 1998; Revision received: 28 May 1998; Accepted: 7 August 1998  相似文献   
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Bronchobiliary fistulas are rare. One aetiological cause is biliary obstruction with secondary suppuration and subsequent hepatic and subphrenic abscesses. Only a few cases of bronchobiliary fistulas in patients with chronic pancreatitis have been reported and we record another case. A 47-year-old white male, with chronic alcohol-induced pancreatitis who had earlier undergone several laparotomies related to this disease, was admitted with a hepatic abscess. Drainage was not successful. The patient developed bilioptysis and a bronchobiliary fistula was diagnosed. The fistulous tract was demonstrated using PTC as well as bronchography. Laparotomy was performed and the fistulous tract was excised. The hepaticoduodenal ligament was completely obstructed by the inflamed pancreatic gland. An earlier but now obstructed cholecystojejunostomy was revised. This case was complicated by episodes of severe gastrointestinal bleeding probably caused by thrombosis of the portal vein and local varices around the gallbladder and common duct.  相似文献   
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Purpose

Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique.

Materials and methods

Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared.

Results

A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10 cm (IQR: 8–12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062).

Conclusions

The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates.  相似文献   
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