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991.
Ohne ZusammenfassungMit 5 Textabbildungen.Herrn Prof. Dr. W. Heubner zum 60. Geburtstag gewidmet.Die Durchführung dieser Untersuchungen wurde durch die weitgehende Unterstützung seitens des Reichserziehungsministeriums und später der Deutschen Forschungsgemeinschaft ermöglicht, denen ich aufrichtig danke.  相似文献   
992.
Peripheral arterial occlusive disease: P-31 MR spectroscopy of calf muscle   总被引:3,自引:0,他引:3  
Williams  DM; Fencil  L; Chenevert  TL 《Radiology》1990,175(2):381-385
The effect of a graded exercise protocol on phosphorus-31 magnetic resonance (MR) spectroscopy of calf skeletal muscle in nine healthy (control) subjects and 16 patients with symptomatic peripheral arterial occlusive disease (PAOD) was assessed. Ankle-brachial pressure indexes were obtained in all 16 patients, and 10 patients underwent peripheral arteriography. Temporal profiles of pH and the inorganic phosphorus (Pi) index were calculated from the spectra. A Pi-index recovery rate constant was calculated for each subject. Arteriograms were graded by calculating the runoff resistance in the limb of interest. The pH profiles during exercise did not differ significantly between the PAOD patients and control subjects. The Pi-index recovery rate constant in the PAOD patients was significantly (P less than .01) smaller than in the control subjects. There was no significant correlation between recovery rate and the ankle-brachial pressure indexes, but there was a strong negative correlation between recovery rates and angiographic resistance grades, with smaller recovery rate constants in patients with increased arterial resistance. It is concluded that P-31 MR spectroscopy shows promise as a direct measure of tissue perfusion.  相似文献   
993.
Fox  AJ; Pelz  DM; Lee  DH 《Radiology》1990,177(1):51
  相似文献   
994.
995.
Reiman  TH; Balfe  DM; Weyman  PJ 《Radiology》1987,163(1):49-56
In a 5-year period, 92 patients with biliary obstruction proximal to the pancreatic segment were evaluated with computed tomography (CT). Seventy-three were judged to have technically optimal studies. Observations of the level of obstruction were compared with data from 50 percutaneous transhepatic cholangiograms; CT data enabled the level of obstruction to be correctly predicted in 46. CT enabled correct prediction of the distribution of obstructing lesions in all 18 patients with intrahepatic obstruction. Forty-four of the 73 patients had pathologic examination of the porta hepatitis. CT findings of obstructing mass and lesser omental nodes resulted in correct prediction of malignancy in 25 (92%) of 27 patients; the absence of such findings enabled correct prediction of benign disease in 13 (77%) of 17 individuals. CT is most valuable as a noninvasive means of planning surgical or radiologic drainage procedures in patients with biliary obstruction.  相似文献   
996.
Zusammenfassung Operative Entfernung eines allm?hlich gewachsenen hydronephrotischen Sackes bei einem 3 Monate alten S?ugling. Es wird auf die Notwendigkeit hingewiesen, sich auch bei S?uglingen und Kleinkindern durch eine cystoskopische Untersuchung Klarheit über die Funktion beider Nieren zu verschaffen, bevor eine Nephrektomié vorgenommen wird. In dem beschriebenen Fall handelte es sich pathologisch-anatomisch um eine kongenitale Hydronephrose bei gesunder anderer Niere. Als Ursache des Leidens wird eine Hemmungsbildung angesehen.  相似文献   
997.
998.
Zusammenfassung Es wird die Aufmerksamkeit auf eine in einmaliger Eruption, besonders an unbedeckten Körperstellen auftretendeBlasenbildung gelenkt, die höchstwahrscheinlich alsatypische Mückenstich. reaktion aufzufassen und demnach alsCulicosis bullosa zu bezeichnen ist. Die Blasen jucken nicht; doch kann ihnen eine typische juckende Mückenstich-Urtica vorausgehen.  相似文献   
999.
The dynamic signal intensity changes at magnetic resonance (MR) imaging in active and chronic wallerian degeneration in the corticospinal tract were evaluated. Forty-three patients with wallerian degeneration seen on MR images after cerebral infarction were studied. When possible, patients with acute stroke were examined with MR imaging prospectively at the onset of symptoms and then at weekly intervals for several months. Focal infarction without distal axonal degeneration is demonstrated for the 1st month following onset of clinical symptoms. At 4 weeks, a well-defined band of hypointense signal appears on T2-weighted images in the topographic distribution of the corticospinal tract. After 10-14 weeks, the signal becomes permanently hyperintense. Over several years, accompanying ipsilateral brain stem shrinkage occurs. The dark signal intensity observed on T2-weighted images between 4 and 14 weeks is believed to result primarily from transitory increased lipid-protein ratio.  相似文献   
1000.
The effectiveness of CT and technetium-99m sulfur colloid (99mTc SC) bone-marrow scans in determining the extent and severity of skeletal involvement in 23 patients with type 1 Gaucher's disease was compared with the effectiveness of conventional radiographic techniques and technetium-99m methylene diphosphonate (99mTc MDP) bone scintigrams. Density measurements obtained by CT proved sensitive in differentiating normal marrow (-50 to -120 H). Scintigrams with the sulfur colloid nuclide demonstrated three distinct patterns of uptake: peripheral expansion of normal marrow (profile B), greater marrow expansion with patchy areas lacking uptake (profile C), and greater loss of uptake with retention of the nuclide in other reticuloendothelial organs and circulation (profile D). CT scans provided greater sensitivity in resolving the extent of marrow involvement in affected areas, while the 99mTc SC scintigrams were more effective in overall assessment of the severity of bone-marrow involvement. Both conventional radiographic techniques and 99mTc MDP bone scans were useful primarily as screening procedures or for evaluating specific involved areas. 99mTc MDP scans were useful in evaluating regional defects (i.e., ischemic necrosis) in certain cases, but no consistent patterns were observed. CT and 99mTc SC scans are useful for determining the extent and severity of Gaucher's disease involvement of bone marrow.  相似文献   
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