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31.
32.

Purpose  

High-energy photons are most commonly used in radiotherapy to treat cancer. Wedge filters are required to obtain homogeneous dose distribution in the patient. Different wedge filter types create different surface doses. In this study, the effect of the virtual and physical wedge filters on the surface and build-up region doses was examined for 6- and 18-MV high-energy photon beams.  相似文献   
33.
We compared the effects of exogenous pentagastrin and meal-stimulated gastrin on plasma immunoreactive calcitonin (iCT) in various studies of 13 normal adult men. Bolus intravenous injection of pentagastrin (0.5 μg/kg) produced increases of iCT in 8 of 9 men. There was a linearly increasing response of iCT concentrations to increasing doses of pentagastrin (0.0625, 0.125, 0.25, and 0.5 μg/kg) and to achieved serum immunoreactive pentagastrin concentrations (r=0.72, P<0.01). To determine the effects of endogenous gastrin upon peripheral iCT concentrations, we measured serum immunoreactive gastrin (iG) and plasma iCT in four men at frequent intervals for 240 min after ingestion of low-(100 mg) and high- (400 mg) calcium meals. Serum iG increased in all subjects, with a peak at ~30 min. However, plasma iCT levels were unchanged from basal throughout the study. The increase of pentagastrin (0.3 pmol/ml) which caused a barely detectable increase of iCT was five-to tenfold greater than the mean maximal increases of gastrin after low- and high-calcium meals (0.04 and 0.06 pmol/ml, respectively). These results suggest that increases of plasma iCT concentrations after administration of pentagastrin in man reflect pharmacologic phenomena and that postprandial gastrin secretion may be insufficient to affect peripheral iCT concentrations.  相似文献   
34.
Selective coronary angiography was carried out in 110 patients (68 women, 42 men; average age 57 +/- 8 years) with significant, isolated, non-ischaemic mitral valve disease. The indication for coronary angiography was angina or myocardial infarction in 42 cases and the investigation was carried out routinely in the other 68 cases. Coronary stenosis greater than 50 p. 100 was demonstrated in 25 cases (22.7 p. 100), 18 single vessel, 5 double or triple vessel disease and 2 cases of stenosis of the left main stem. The incidence of coronary artery disease was higher in patients with cardiovascular risk factors (0 factors: 13 p. 100; 1 factor: 22 p. 100, 2 or 3 factors: 45 p. 100; p less than 0.01). The coronary patients had higher mean pulmonary artery pressures (33 +/- 16 mmHg vs 25 +/- 8 mmHg, p 0.001), higher left ventricular end diastolic pressures (12.5 +/- 7 mmHg vs 9 +/- 5 mmHg, p less than 0.01) and greater left ventricular end diastolic volumes (83 + 40 ml/m2 vd 59 +/- 29 ml/m2, p less than 0.01). There was no difference in segmental wall motion between coronary and non coronary patients. 89 patients were referred for surgery, 17 of whom had coronary artery disease. 5 patients underwent coronary bypass surgery. The incidence of peroperative cardiac complications (low output, ventricular arrhythmias, myocardial infarction) was higher in the coronary patients (53 p. 100 vs 18 p. 100, p less than 0.01). The 6 year survival rate was 75 +/- 8 p. 100.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
35.
36.
A total of 300 patients were operated upon for heart valve disease by the same surgeon. The affected valve was the aortic in 200 cases and the mitral in the other 100 patients. The tricuspid valve, coronary arteries, and myocardium were not involved. This report attempts to define the frequency progression, prognosis, and significance of conduction abnormalities which appear during the course of this operation. In 35 cases, of which 16 were post-operative deaths, a histological examination of the conduction pathways was possible. The conclusions to be drawn from these observations are: Conduction abnormalities after single aortic or mitral valve replacement are frequent (1 out of 3 patients).  相似文献   
37.
Aortic dissection is extremely rare in children. Although it usually presents with severe chest pain, atypical clinical presentations mimicking various illnesses may cause misdiagnosis. In this report, the case of a 14‐year‐old boy with symptoms suggestive of acute abdomen, which was finally diagnosed as aortic dissection, is discussed.  相似文献   
38.
The aim of this cooperative study was to analyse the clinical profile of subvalvular aortic stenosis (SVAS) in adults. Thirty one cases were collected : patients aged 17 to 60 years (average 34 years). The diagnosis was confirmed in all patients either at surgery (30 cases) or at autopsy (1 case). The overall incidence of SVAS in patients with fixed obstruction to left ventricular ejection operated in the same period was 3.5%. Associated congenital malformations were detected in 15% of cases but intracardiac shunts were rare. Adult SVAS is a purer malformation than in children, probably because of spontaneous and surgical selection. The anatomical type of stenosing lesion in this series was a subaortic ring or membrane; 45% of patients, usually over 40 years of age (7 out of 9) had localised septal hypertrophy at the level of the diaphragmatic obstruction. The clinical presentation was that of mixed aortic disease with associated stenosis and regurgitation. Over 80% of patients had aortic incompetence diagnosed clinically (26 out of 31 cases) or on aortography (24 out of 25 cases); the regurgitant flow was assessed as mild in 15 cases, moderate in 6 cases and severe in 3 cases. There were obvious valvular lesions at surgery in 19 cases, especially in patients over 40 years of age (8 out of 9 cases). The mechanism was variable : non-specific (8 cases), destructive (6 cases), rheumatic (2 cases) or congenital (3 cases). Bacterial endocarditis was particularly common (26% of cases). Adult SVAS is a particularly difficult clinical diagnosis : the electrocardiogram and chest X-ray are not very informative.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
39.

Purpose

The aim of our study is to research the role and efficacy of cerebral oximetry in predicting neurologic prognosis when applied during TTM to patients experiencing coma after CA.

Methods

This study was performed on surviving adult comatose patients after CA treated with TTM. The average scores of rSO2 was measured at 6 h intervals for the first 2 days and once a day for the following 3 days with a NIRS device during TTM. The CPC scale was used to define the neurologic outcomes of patients. We compared the correlations of rSO2 values between good (CPC 1–2) and poor (CPC 3–5) neurologic outcomes in CA patients.

Results

There was no statistically significant difference identified between the prognosis groups in terms of rSO2, CPR durations, hemoglobin values and admission body temperature (p > 0.05). When the variation in rSO2 values over time is investigated, though there was no significant difference between the good and poor prognosis groups, it appeared to fall in the first 6 h in both prognosis groups. The median NT-proBNP and lactate values were observed to be higher in the poor prognosis group.

Conclusion

There is no significant correlation between rSO2 values and neurologic outcomes. Multimodal monitoring methods may be useful and further studies with a larger patient population are necessary in this area.  相似文献   
40.
Clinical Rheumatology - Autoimmune pancreatitis (AIP) type 1 is an IgG4-related disease (IgG4-RD), characterized by inflammatory pseudotumors and histologically by dense lymphoplasmacytic...  相似文献   
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