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51.
A method is proposed for estimating the volume blood flow of deep lying vessels in the foetus and in adult portal vein and renal vessels. The equipment combines a 3.5 MHz linear array scanner with a 2 or 4 MHz pulsed Doppler. The pulsed Doppler tranducer is connected to the linear array by two movable arms. A real time spectrum analyser is used to process the Doppler signals. A water bath was used to perform an in vitro calibration of the complete system and to adjust the registration of the Doppler sample volume with the echo picture. Several possible inaccuracies in vessel diameter measurement are discussed and the mean of several caliper measurements described by Eik-Ness (1982) is used. Time Motion is thought to be the better method but is more complicated in practice.  相似文献   
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R H Teague  A E Read 《Gut》1975,16(10):792-795
One hundred and fifty cases of ulcerative colitis were assessed by total colonoscopy with multiple biopsies. Inflammatory polyposis was found in 25 (17%) cases and six of these had a large (greater than 1-5 cm) solitary polyp which radiologically resembled carcinoma in four cases. Adenomatous polyps were discovered in four cases. Three carcinomas were found at endoscopy, of which two were entirely unsuspected. In all cases endoscopic polypectomy or surgical intervention was performed to establish the exact histological diagnosis.  相似文献   
54.
Prenatal phthalate exposure impairs testicular function and shortens anogenital distance (AGD) in male rodents. We present data from the first study to examine AGD and other genital measurements in relation to prenatal phthalate exposure in humans. A standardized measure of AGD was obtained in 134 boys 2-36 months of age. AGD was significantly correlated with penile volume (R = 0.27, p = 0.001) and the proportion of boys with incomplete testicular descent (R = 0.20, p = 0.02). We defined the anogenital index (AGI) as AGD divided by weight at examination [AGI = AGD/weight (mm/kg)] and calculated the age-adjusted AGI by regression analysis. We examined nine phthalate monoester metabolites, measured in prenatal urine samples, as predictors of age-adjusted AGI in regression and categorical analyses that included all participants with prenatal urine samples (n = 85). Urinary concentrations of four phthalate metabolites [monoethyl phthalate (MEP), mono-n-butyl phthalate (MBP), monobenzyl phthalate (MBzP), and monoisobutyl phthalate (MiBP)] were inversely related to AGI. After adjusting for age at examination, p-values for regression coefficients ranged from 0.007 to 0.097. Comparing boys with prenatal MBP concentration in the highest quartile with those in the lowest quartile, the odds ratio for a shorter than expected AGI was 10.2 (95% confidence interval, 2.5 to 42.2). The corresponding odds ratios for MEP, MBzP, and MiBP were 4.7, 3.8, and 9.1, respectively (all p-values < 0.05). We defined a summary phthalate score to quantify joint exposure to these four phthalate metabolites. The age-adjusted AGI decreased significantly with increasing phthalate score (p-value for slope = 0.009). The associations between male genital development and phthalate exposure seen here are consistent with the phthalate-related syndrome of incomplete virilization that has been reported in prenatally exposed rodents. The median concentrations of phthalate metabolites that are associated with short AGI and incomplete testicular descent are below those found in one-quarter of the female population of the United States, based on a nationwide sample. These data support the hypothesis that prenatal phthalate exposure at environmental levels can adversely affect male reproductive development in humans.  相似文献   
55.
This document is a revision of a previously published cardiothoracic curriculum for diagnostic radiology residency, and reflects interval changes in the clinical practice of cardiothoracic radiology and changes in the Accreditation Council for Graduate Medical Education (ACGME) requirements for diagnostic radiology training programs. The revised ACGME Program Requirements for Residency Education in Diagnostic Radiology went into effect December 2003.  相似文献   
56.
PURPOSE: To describe a laparoscopic hand-assisted approach to renal autotransplantation that allows both harvest and transplant through the same incision. PATIENTS AND METHODS: Three patients underwent renal autotransplantation from May 2003 to April 2004, two for loin pain-hematuria syndrome and one for severe ureteral-stricture disease. Two patients underwent autotransplantation on the left and one on the right. Hand-assisted laparoscopy was planned such that inferomedial extension of the hand-port incision would provide adequate exposure of the iliac vessels for autotransplantation. RESULTS: The average operative time was 240 minutes, the warm ischemia time was 2 minutes 43 seconds, and the hospital stay was 3 days. All three patients had successful graft function by postoperative renal scan with a mean follow-up of 7.1 months. CONCLUSION: Hand-assisted laparoscopic renal harvest for autotransplantation can be completed with placement of the hand port such that transplantation can be accomplished through the same incision. As many of these patients have had multiple prior retroperitoneal operations, the intracorporeal hand can greatly facilitate these potentially difficult dissections with no added morbidity.  相似文献   
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58.
Radiology of community-acquired pneumonia   总被引:1,自引:0,他引:1  
This article reviews the radiographic appearance of common community-acquired pneumonia. Included are the common bacterial pneumonias, tuberculosis, fungal pneumonia, pneumocystis pneumonia, and viral pneumonias. The various radiographic appearances and the clues for differentiating the pneumonias are discussed. Images enhance the discussion.  相似文献   
59.
Background Pancreatic cancer has a dismal prognosis. Few patients are suitable for surgical resection, leaving the majority requiring symptom palliation. Current palliative techniques such as surgical bypass and endoscopic retrograde cholangiopancreatography (ERCP) are imperfect. A novel palliative therapy combining the symptom control of surgical bypass with the minimally invasive nature of ERCP is required.Methods Perductal electrolytic ablation of pancreatic tissue, in a porcine model, was performed. There were two survival groups of 2 weeks (n = 4) and 8 weeks (n = 4). Postoperatively, serum biochemistry, amylase and C-reactive protein (CRP) were assessed. Histological examination of the pancreas, lungs, and kidneys was performed to determine the presence of acute pancreatitis or systemic inflammatory response.Results An immediate transient increase in both amylase and CRP was seen. Although pancreatic histology demonstrated localised necrosis at the electrolytic site at 2 weeks, there was no evidence of generalized pancreatitis or a systemic inflammatory response at either 2 or 8 weeks.Conclusions This study suggests that, although there is localized pancreatic necrosis and transient hyperamylasemia, perductal pancreatic electrolytic ablation is safe, with neither generalized pancreatitis nor a systemic inflammatory response, in the medium and long term. Although performed in normal porcine pancreas, because of the absence of a large-animal model of pancreatic cancer, this study suggests that electrolytic pancreatic ablation is safe. This technique may have a role in the palliation of pancreatic cancer, especially if delivered via a minimally, invasive approach, and warrants further investigation.  相似文献   
60.

Background  

The objective of this study was to assess the status of oxidative stress in term small for gestational age (SGA) newborn infants born to undernourished mothers by estimating levels of erythrocyte superoxide dismutase (SOD), catalase, reduced glutathione, and serum malondialdehyde (MDA) in cord blood and comparing them to healthy appropriate for gestational age (AGA) controls. This was done in a case control design at a tertiary level teaching hospital.  相似文献   
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