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101.
Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
102.
Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying.  相似文献   
103.
Hydatid cyst disease is encountered in Turkey frequently. Rupture of a pulmonary cyst into the pleural cavity is rare, but represents the most serious complication of the hydatid disease. Surgical intervention was carried out in all cases in our clinic when expansion of the lungs could not be achieved. Open ends of the bronchus were closed and the pericyst layer was sutured after the removal of the germinative layer. We here present 5 cases of hydatid cysts with the above mentioned complication.  相似文献   
104.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
105.
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
106.
107.

Background/Purpose

The aim of this study was to evaluate the effects of maternal nicotine exposure during gestation on injury severity of small intestine in the newborn rats subjected to hypoxia-reoxygenation and cold stress.

Methods

A total of 21 Sprague-Dawley pregnant rats were divided into 3 equal groups. The groups were labeled as group 1, control group; group 2, hypoxia-reoxygenation group; and group 3, nicotine-hypoxia-reoxygenation group. The rats of group 3 were exposed to nicotine via subcuticular injection for the last week of gestation (2 mg/kg/d). Newborn rats were collected immediately after birth to prevent suckling of maternal milk (40 rat pups in group 1, 43 rat pups in group 2, and 41 rat pups in group 3). Litters in groups 2 and 3 were stressed twice daily with asphyxia followed by cold (4°C for 10 minutes) stress to induce hypoxic intestinal injury which is relevant to human necrotizing enterocolitis. Breathing 100% CO2 for 10 minutes in a chamber followed by 10-minute 100% O2 breathing was the asphyxia model repeated twice daily. After hypoxia-reoxygenation and cold stress, newborn rats were returned to their mother's cages. This protocol was repeated for the following 2 days, and the rat pups were decapitated on the third day. Using this protocol of asphyxia and cold stress, all of neonatal rats developed clinical and pathological signs of hypoxia-induced intestinal injury. The entire gastrointestinal tract was removed and examined macroscopically. A 2-cm section of distal ileum from each animal was taken for histopathological and biochemical examinations. Histological changes in ileal architecture were scored and graded from 1 to 5. The remaining intestinal tissues of the animals were used for lipid peroxidation analysis.

Results

Typical signs of hypoxia-induced intestinal injury were observed in the 2 experimental groups (groups 2 and 3) macroscopically. There were more grades 3 and 4 injuries in group 3 (P < .05). The malondialdehyde levels were elevated in groups 2 and 3 (P < .001). The malondialdehyde levels of the group 3 were also significantly higher than group 2 (P < .01).

Conclusions

Maternal nicotine exposure during gestation results in higher grade histological injury in newborn rats subjected to hypoxia-reoxygenation and cold stress.  相似文献   
108.
BACKGROUND AND OBJECTIVE: This randomized, double-blinded clinical study was designed to compare the efficacy and safety of remifentanil and morphine administered using intravenous (i.v.) patient-controlled analgesia (PCA) for postoperative analgesia after major abdominal surgery during the first 24 postoperative hours. METHODS: Sixty-nine patients were randomly allocated into two groups, each receiving remifentanil or morphine. The first group received i.v. remifentanil PCA with a loading dose of 45 microg, a maintenance dose of 1 microg min(-1), a bolus dose of 15 microg and a lockout interval of 10 min during the first 24 postoperative hours. The second group received i.v. morphine PCA with a loading dose of 5 mg, a maintenance dose of 0.3 mg h(-1), a bolus dose of 1 mg and a lockout interval of 15 min. Age, weight, sex, history of general anaesthesia, duration of surgery and time spent in the post-anaesthesia care unit were recorded. Preoperative pulse rate, systolic and diastolic blood pressures (BP), respiration rate and arterial blood gases were collected. Pulmonary function was tested before induction of anaesthesia, as well as at 4 and 26 h after operation. Pulse rate, systolic and diastolic BP, respiration rate, arterial blood gases, sedation and visual analogue scores, and presence of side-effects in the recovery room and on the ward for 24 h were recorded at 0, 1, 2, 4, 6, 12, 18 and 24 h after operation. Total drug use, number of boluses delivered, number of boluses demanded and delivery/demand ratio were collected. RESULTS: Sixty patients were evaluated. The groups did not differ in age, weight, sex, history of general anaesthesia, duration of surgery or time spent in the recovery unit. There were also no clinically relevant differences between the groups with regard to haemodynamic and respiratory parameters as well as sedation and visual analogue scores (P > 0.05). More bolus doses were demanded and delivered and the delivery/demand ratio was significantly higher in the remifentanil group (P < 0.05). There was no finding suggesting acute opioid tolerance during remifentanil or morphine PCA. CONCLUSION: The i.v. remifentanil PCA with the chosen dosage regimen after abdominal surgery produces postoperative analgesia and has cardiovascular side-effects similar to those achieved with i.v. morphine. Special attention must be given to respiratory depression during establishment of PCA with remifentanil.  相似文献   
109.
Alkaptonuria is a metabolic disorder in which homogentisic acid oxidase is absent. Therefore, homogentisic acid accumulates in cartilage and connective tissues. We can diagnose ochronotic arthropathy, a manifestation of long standing alkaptonuria, through careful radiological, physical, and laboratory examination. In this report, we describe 4 cases of ochronotic arthropathy to which we applied cementless total hip prosthesis due to severe hip involvement.  相似文献   
110.
BACKGROUND: The management of the apical multiple muscular ventricular septal defects (VSDs) remains still controversial. There are various surgical techniques and approaches for closure of "Swiss-cheese" VSDs. In this study, we report the outcome of multiple muscular VSDs repair, using the septal obliteration technique. METHODS: We used the septal obliteration technique in five "Swiss-cheese" ventricular septal defects cases through right atriotomy. Four of the cases had isolated multiple VSDs. One case also had an aortic arch interruption type A, which was repaired prior to cardiopulmonary bypass. Their ages varied between 43 days and 6 years. RESULTS: We did not experience any mortality or serious morbidity. Tracheostomy was required in one patient. There was no important residual shunt in postoperative period, except a minimal shunt in one case. CONCLUSION: The closure technique of "Swiss-cheese" trabecular multiple VSDs using a large single patch was not troubling. Transatrial approach prevented postoperative problems of ventricular incision. Using a large needle with a large pledgett is the key, which provides deep tissue penetration to avoid residual shunt.  相似文献   
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