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121.
Priyadarshini Arunakumar DM Anoop Ayyappan MD Deepa Sasikumar DM KM Krishnamoorthy DM 《Echocardiography (Mount Kisco, N.Y.)》2018,35(5):733-734
A 12‐year‐old child presented with recurrent respiratory infections and was diagnosed with Scimitar syndrome. Drainage of IVC and course of aberrant arterial supply from aorta were not clear by echocardiogram, and hence, additional imaging was planned. CT unraveled the presence of a rare combination of anomalous pulmonary venous connection (APVC) to IVC, with near‐atresia/severe stenosis of IVC, superior to the drainage of scimitar vein. There was a prominent azygos vein with preferential contrast opacification on lower limb injection. 相似文献
122.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献
123.
Seven patients with benign lymphoid hyperplasia of the palate are reported. Clinically, these lesions presented as painless non-ulcerated masses that were unilateral in 6 of the cases and bilateral in one. Microscopically, the lesions were characterized by a mixed lymphoid infiltrate, germinal centres and vascular channels with hyperplasia of endothelial cells. The patients were followed for 3–10 years subsequent to diagnosis. One patient had 2 sequential lesions on opposite sides of the palate. Another patient with lesions of both submandibular salivary glands in addition to the palate developed rheumatoid arthritis, xerophthalmia and serologic changes consistent with systemic autoimmune disease. To date, none of the patients developed signs and symptoms of lymphoma or leukemia. The etiology of these lesions is unknown. Their distinction from lymphoma of the palate, as well as their possible relationship to the benign lymphoepithelial lesion of palatal mucous glands, is discussed. 相似文献
124.
A I Gadallah G M Khalil W H Dees M A Roshdy A S Marzouk D E Sonenshine A J Main 《Journal of medical entomology》1990,27(5):763-772
Changes in DNA, RNA, total lipids, phospholipids, and proteins and the activity of certain enzymes and pattern of their isozymes were studied in Hyalomma dromedarii Koch during embryogenesis. Total proteins fluctuated with a net increase (P less than 0.05) on day 20. Total lipids increased during the first half of embryogenesis and then declined with a net decrease to about 60% of the original level. Total phospholipids decreased to half this original level. DNA content increased greatly during cleavage, gastrulation, and organogeny and RNA increased during cleavage and blastula formation. Glucose-6-phosphate dehydrogenase (G6PDH) activity decreased (P less than 0.05), reaching 20% of its original level on day 12. Malic acid dehydrogenase (MDH) activity remained nearly unchanged throughout embryogenesis. Lactic acid dehydrogenase (LDH) activity increased greatly, with the highest level on day 14 with no further change. Acetylcholinesterase (AchE) activity increased greatly during the first 12 d, with no significant change thereafter. Acid (ACP) and alkaline (ALP) phosphatase activity increased during the first 12 d and declined returning to the original level on day 20. Seven AchE and 5 LDH isozymes were detected during different embryogenesis stages. Two MDH, 2 ACP, 1 ALP, and 2 G6PDH isozymes were detected throughout embryogenesis. Treating the mother with 20-hydroxyecdysone was associated with increases in protein and RNA contents and G6PDH and AchE activity and with decreases in ACP and ALP activity in the embryos. 相似文献
125.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
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128.
Peripheral nerve injuries of the shoulder in the athlete 总被引:1,自引:0,他引:1
Athletic injuries about the shoulder resulting in lesions of the suprascapular, axillary, long thoracic, musculocutaneous, and spinal accessory nerves are uncommon. Yet these lesions are well described in the literature, and they may occur as isolated injuries. Rarely do they occur following surgical procedures about the shoulder of the athlete. Furthermore, these injuries may mimic other more commonly occurring athletic injuries thus giving rise to diagnostic confusion. The clinical syndromes that result from these isolated lesions have been discussed, along with their mechanisms of injury. Increased awareness, careful physical examination, and EMGs may greatly simplify the diagnosis. The treatment and prognosis for these injuries has been outlined. 相似文献
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