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41.
Tetralogy of Fallot was diagnosed in an acyanotic 11-month-old dog. Predicted pressure gradient across the pulmonic valve, as assessed by use of continuous wave Doppler echocardiography, was 94.5 mm Hg. Bidirectional shunting was identified by means of selective angiography. Open-heart correction was performed, using a transatrial approach with limited ventriculotomy and cardiopulmonary bypass. The hypertrophied infundibulum was resected, the ventricular septal defect was closed primarily, and a transannular pericardial patch graft was applied. Pressure gradients across the pulmonic valve were 52.9 and 22.8 mm Hg 2 weeks and 4 months after surgery, respectively. Advances in cardiopulmonary bypass, anesthetic management, and use of the transatrial approach may improve the success of open-heart correction of tetralogy of Fallot in dogs.  相似文献   
42.
P C?té  BG Kreitz  JD Cassidy  AK Dzus  J Martel 《Canadian Metallurgical Quarterly》1998,23(7):796-802; discussion 803
STUDY DESIGN: Study of the diagnostic accuracy and interexaminer reliability of scoliosis diagnostic tests. OBJECTIVES: To estimate the sensitivity, specificity, and predictive value of the Scoliometer (National Scoliosis Foundation, Watertown, MA) and Adam's forward bend test in diagnosing scoliosis, and to determine the interexaminer reliability of the Scoliometer and Adam's forward bend test. SUMMARY OF BACKGROUND DATA: Exposure to diagnostic radiation in patients with adolescent idiopathic scoliosis may result in a small but significant increase in cancer rates. The full-spine radiographic examination remains the standard procedure for the assessment of scoliosis. There is a need for a valid and reliable noinvasive test to assess scoliosis. METHODS: Two examiners independently assessed 105 patients presenting to a scoliosis clinic for trunk asymmetry with Adam's forward bend test and axial trunk rotation with the Scoliometer. The Cobb method served as the gold standard. RESULTS: The interexaminer agreement for the Scoliometer is excellent in the thoracic spine and substantial in the lumbar spine. The interexaminer measurement error shows poor precision for thoracic and lumbar Scoliometer measurements. The interexaminer agreement for Adam's forward bend test is substantial in the thoracic spine and poor in the lumbar spine. Adam's forward bend test is more sensitive than the Scoliometer in detecting thoracic curves measuring 20 degrees or more by the Cobb method. Receiver operating characteristic curve analysis suggests that the use of the Scoliometer marginally improves the ability of diagnosing a scoliosis in the thoracic spine. CONCLUSIONS: The Scoliometer and Adam's forward bend tests have adequate interexaminer reliability for the assessment of thoracic curves. The Scoliometer has better interexaminer agreement in the lumbar spine. However, the Scoliometer has a high level of interexaminer measurement error that limits its use as an outcome instrument. Because Adam's forward bend test is more sensitive than the Scoliometer, the authors believe that it remains the best noninvasive clinical test to evaluate scoliosis.  相似文献   
43.
The function of organic solar cells is based upon charge photogeneration at donor/acceptor heterojunctions. In this paper, the origin of the improvement in short circuit current of poly(3‐hexylthiophene)/6,6‐phenyl C61‐butyric acid methyl ester (P3HT/PCBM) solar cells with thermal annealing is examined. Transient absorption spectroscopy is employed to demonstrate that thermal annealing results in an approximate two‐fold increase in the yield of dissociated charges. The enhanced charge generation is correlated with a decrease in P3HT's ionization potential upon thermal annealing. These observations are in excellent quantitative agreement with a model in which efficient dissociation of the bound radical pair into free charges is dependent upon the bound radical state being thermally hot when initially generated, enabling it to overcome its coulombic binding energy. These observations provide strong evidence that the lowest unoccupied molecular orbital (LUMO) level offset of annealed P3HT/PCBM blends may be only just sufficient to drive efficient charge generation in polythiophene‐based solar cells. This has important implications for current strategies to optimize organic photovoltaic device performance based upon the development of smaller optical bandgap polymers.  相似文献   
44.
A method for the determination of aspirin esterase activity in serum is described. Sera from 59 pregnant women who were habitual aspirin users were found to have a mean enzyme activity value statistically lower than those of 68 non-pregnant women controls or of 12 pregnant women controls who were either occasional users of the drug or were non-users. The distribution of enzyme activity in the experimental group was also significantly different from that of the control group. It is postulated that the low enzyme activity may further aggravate the injurious effects of high intake of aspirin.  相似文献   
45.
Physical training is associated with a reduction of intrinsic sinoatrial activity; the present study examined the role of the parasympathetic nervous system in this reduction. Six groups of rats were studied for 10 weeks: inactive control; treadmill exercised; parasympathetic receptor blockade with atropine; exercise plus atropine; parasympathetic receptor stimulation with carbachol; and exercise plus carbachol. In vivo ISF (cardiac frequency 20 min after injection of propranolol and atropine) was measured at 3-week intervals. At the end of 10 weeks the right atrium was excised, in vitro measurements were made of ISF, and chronotropic dose-response curves to acetylcholine and norepinephrine were established. In vivo, ISF was reduced with time, the greatest reduction being found in the exercise plus atropine group; the treadmill-exercised and the atropine-treated groups also had a greater reduction than the control group. In vitro, no differences were observed in acetylcholine responses. The maximum norepinephrine chronotropic response was reduced in the treadmill-exercised and the exercise plus atropine groups. The maximum norepinephrine-induced frequency correlated with the in vitro ISF (r = 0.75). Thus, ISF was reduced with training, but this effect was independent of parasympathetic activity. The properties of the sinoatrial node which set ISF also influenced the maximum norepinephrine response.  相似文献   
46.
Of 32 patients with Beh?et's disease, 21 had uveitis. The uveitis was seldom the initial manifestation of systemic disease, but once established, it tended to become chronic and bilateral, involving the anterior and posterior segments. Hypopyon was a relatively uncommon occurrence in this series. All patients with uveal inflammation had obvious cellular reactions within the vitreous body. Other posterior segment manifestations of the disease included localized retinal edema, macular edema, disc edema, retinal pigmentary changes, and accumulation of exudative material in the deep retina. One patient developed a necrotizing retinitis with deep retinal exudation and subsequent retinal detachment. Occlusions of retinal vessels were common. Neuro-ophthalmologic manifestations of Beh?et's disease included cranial nerve palsies, a homonymous hemianopic field defect, and papillitis.  相似文献   
47.
48.
A series of 238 hydronephrotic kidneys in 219 children is reported. The condition was more common in the male than in the female subject and occurred more frequently on the left side. It was often bilateral, especially in infants, with an abdominal mass as the common presenting feature. Loin or abdominal pain was the most frequent complaint in older children. In some cases hydronephrosis presented as a ruptured kidney following trauma. Only 1 patient was hypertensive. The lesion was asymptomatic in 18 cases and the incidence of urinary infection was low. Dismembered pyeloureteroplasty was the procedure of choice for reconstruction. Preliminary nephrostomy was used rarely and nephrectomy was done in 10 per cent of the kidneys. Of the 7 reoperations 4 were for persistent obstruction and 3 were because stones had formed after the pyeloplasty. The late results, assessed clinically and radiologically, have been entirely satisfactory. Many kidneys of initially doubtful value showed useful improvement after reconstructive operation and no secondary nephrectomies were performed. The only death in the series occurred 2 1/2 years postoperatively and was unrelated to the urinary tract.  相似文献   
49.
The nasal region of 12-day-old mouse embryos was examined with the electron microscope to determine whether a surface coat and membrane specializations are involved in epithelial fusion between the medial and lateral nasal swellings. Ruthenium red was used to examine the distribution of the surface coat. Prior to contact, a surface coat is always present over the epithelial linings of the nasal swellings in the region of presumptive fusion, and it is often heavier in the fusing than in the non-fusing regions. At the point of initial contact, the coat is present as a thin film between touching superficial cells, suggesting that it may mediate epithelial contact. The initial contact between the cells of the medial and lateral nasal swellings is made by short projections from one superficial cell to the surface of an opposing superficial cells meet. The contacting membranes, which are separated by a distance of approximately 6-10 nm and show an increased electron-density, probably provide a firm adhesion between the nasal swellings.  相似文献   
50.
During a 32-month period 2047 patients suspected of having heart attacks were admitted to hospital and were followed up prospectively. Out of 1480 eventually found to have definite or probable myocardial infarction, 483 had initially been admitted to an ordinary medical ward because of the shortage of coronary care unit (CCU) beds. More patients aged over 65 had been admitted to a ward than to a CCU, and more patients aged 65 or less had been admitted initially to a CCU. Within each age group, however, patients admitted initially to a CCU were clinically similar to those admitted initially to a ward. There was a higher proportion of successful resuscitations among patients admitted to a CCU, but there was no significant difference in mortality in either age group between patients admitted to a CCU and a ward.  相似文献   
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