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91.
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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   
93.
Magnetic resonance imaging (MRI) of the brain was used to examine the morphology and dimensions of the pituitary gland in 18 patients with eating disorders (8 anorectics and 10 bulimics), in comparison with 13 healthy volunteers. None of the 18 patients with anorexia or bulimia had any radiological evidence suggestive of pituitary macroadenoma, cyst, or empty sella. Measurements revealed that the anorectics and bulimics had smaller pituitary gland cross-sectional areas (p less than 0.05) and smaller pituitary gland heights, compared with healthy controls. These preliminary findings in anorectics and bulimics are suggestive of pituitary atrophy secondary to nutritional or endocrine alterations, rather than a primary pituitary pathology.  相似文献   
94.
Computed tomographic (CT) patterns of intracranial hemorrhage (ICH) were determined in 1,696 patients undergoing thrombolytic therapy for acute myocardial infarction. ICH occurred at 33 sites in 0.77% of patients (n = 13). Thirty-six percent of hemorrhages (n = 12) were intraparenchymal, 33% (n = 11) were subdural, 24% (n = 8) were subarachnoid, and 6% (n = 2) were intraventricular. Eight-four percent (n = 26) of all nonventricular hemorrhages were supratentorial in location. The most common site of ICH was supratentorial and intraparenchymal (10 of 33). In 11 of the 13 patients with ICH, clinical symptoms occurred within 24 hours of the initiation of thrombolytic therapy. A fatal outcome resulted in three of the four patients who had clinical symptoms within 3.5 hours after beginning thrombolytic therapy. The CT findings of multiple intracranial bleeding sites, substantial mass effect with midline shift, and large-volume intraparenchymal hematomas were associated with increased mortality. ICH associated with thrombolytic therapy for acute myocardial infarction has a grave prognosis, with 62% of patients dying during hospitalization.  相似文献   
95.
Mann  LC; Hawes  DR; Ghods  M; Bednar  EJ; Potchen  EJ 《Radiology》1987,164(1):121-122
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography.  相似文献   
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Abnormalities of lymphocyte subsets, especially low absolute number of helper T cells, are characteristically present in acquired immune deficiency syndrome (AIDS). Similar abnormalities can be found in patients with persistent generalized lymphadenopathy (PGL) or AIDS-related complex (ARC) and, to a lesser degree, in asymptomatic people who have been exposed to human T-lymphotropic virus type III (HTLV-III). Nevertheless, there appears to be a widespread perception that lymphocyte subset analysis may be useful in AIDS case finding within high-risk groups. We evaluated the diagnostic utility of absolute number of helper T cells and ratio of helper to suppressor T cells in 33 patients with AIDS, 43 patients with PGL who had been referred for lymph node biopsy, 90 patients with PGL and 195 male homosexual controls. At conventional cutoff levels the tests did not appear to revise the probability of AIDS upward to any clinically significant degree when the pretest probability of AIDS was low. Lymphocyte subset analysis does not appear to be a cost-effective method of AIDS case finding in identified groups at risk in which the prevalence of AIDS is low.  相似文献   
100.
EJ Lee  ; CA Schiffer 《Transfusion》1989,29(5):384-389
Sixty consecutive patients with untreated acute leukemia alternately received either ABO-matched or ABO-mismatched random-donor platelet transfusions prepared from pooled platelet concentrate stored for 1 to 3 days. Patients were assigned randomly to receive matched or mismatched platelets as their first transfusion, and the first four transfusions were analyzed. In 40 evaluable patients, there was no significant difference (paired t test) between the 10-minute posttransfusion corrected count increments (CCI) of the initial transfusions of matched and mismatched platelets. In contrast, the second matched transfusion was significantly better than the second mismatched transfusion. This effect of ABO compatibility was particularly pronounced in a subset of patients. Six patients in whom mismatched transfusions were consistently inferior to matched transfusions had either a significant increase in anti-A or -B isoagglutinin titers following the first transfusion or elevated titers before or at the conclusion of the study. Conversely, in five patients in whom there was no apparent effect of ABO mismatching, only one had an increase in isoagglutinin titer. Platelet survival was not altered as the ratio of 18-hour to 10-minute posttransfusion CCl was 0.6 for both matched and mismatched platelet transfusions. These data demonstrate that ABO compatibility can affect the results of random-donor platelet transfusions and that patients who experience poor increments from ABO-mismatched platelets may benefit from a trial of ABO-compatible platelets before the initiation of HLA-matched platelet transfusion.  相似文献   
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