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91.
This study was undertaken to identify the clinical value of incidentally detected lesions (IDLs) in the gastrointestinal tract (GIT) with (18)F-FDG PET/CT. METHODS: The reported database of 3,281 patients who underwent partial-body (18)F-FDG PET/CT scans from April 2001 to September 2003 was reviewed. Patients with incidental (18)F-FDG accumulations in the GIT that were associated with concomitant abnormal soft-tissue density or wall thickening on the native CT were evaluated. Incidental PET/CT findings were correlated with endoscopic and histopathologic results. RESULTS: According to our selection criteria, 98 (3%) of the 3,281 patients had an IDL of the GIT on (18)F-FDG PET/CT. Correlative endoscopic findings were available in 69 (70%) of 98 patients. Of these, 13 patients (19%) were harboring newly occurring cancers of the GIT in addition to preexisting aerodigestive tract tumors (n = 12) and malignant melanoma (n = 1). Twenty-nine (42%) patients were identified with precancerous lesions, such as advanced colonic adenomas (n = 27), Barrett's esophagus (n = 1), and intestinal metaplasia of the gastric mucosa (n = 1). Inflammatory and other benign GIT lesions were detected in 12 (17%) and 6 (8%) patients, respectively. In 9 (13%) patients, PET/CT was false-positive, showing normal findings in subsequent endoscopic examinations. In 20 (28%) of 69 patients, PET/CT findings had a relevant impact on the clinical management. Twenty-nine (30%) of the 98 patients were not subject to a further endoscopic examination because of the extent and nature of the primary tumor (n = 17), loss to follow-up (n = 7), death shortly after PET (n = 3), and patient unwillingness (n = 2). CONCLUSION: Although IDLs of the GIT on (18)F-FDG PET/CT scans are found only in about 3% of cases, they are associated with a substantial risk of an underlying cancerous or precancerous lesion. Early identification of these occult lesions may have a major impact on the patients' management and outcome.  相似文献   
92.
Background Magnetic resonance (MR) imaging provides direct, non‐invasive measurements of gastric function and emptying. The inter‐observer variability (IOV) of MR volume measurements and the most appropriate analysis of MR data have not been established. To assess IOV of total gastric volume (TGV) and gastric content volume (GCV) measurements from MR images and the ability of standard power exponential (PowExp), and a novel linear exponential (LinExp) model to describe MR data. Methods Ten healthy volunteers received three different volumes of a liquid nutrient test meal (200–800 mL) on 3 days in a randomized order. Magnetic resonance scans were acquired using a 1.5T system every 1–5 min for 60 min. Total gastric volume and GCV were measured independently by three observers. Volume data were fitted by PowExp and LinExp models to assess postprandial volume change and gastric emptying half time (T50). Key Results An initial rise in GCV and TGV was often observed after meal ingestion, thereafter GCV and TGV decreased in an approximately linear fashion. Inter‐observer variability decreased with greater volumes from 12% at 200 mL to 6% at 600 and 800 mL. Inter‐observer variability for T50 was <5%. PowExp and LinExp models provided comparable estimates of T50; however, only LinExp described dynamic volume change in the early postprandial period. Conclusions & Inferences Gastric MR provides quantitative measurements of postprandial volume change with low IOV, unless the stomach is nearly empty. The novel LinExp model describes the dynamic volume changes in the early postprandial period more accurately than the PowExp model used in existing gastric emptying studies.  相似文献   
93.
European Child & Adolescent Psychiatry - The objective of this study was to investigate the stability and predictive utility of autistic traits (ATs) in youth with...  相似文献   
94.
GM Makhlouf 《Gastroenterology》1997,112(6):2111-2113
This article has no abstract. To view the article, select the "View Print Version (PDF)" link above.  相似文献   
95.
OBJECTIVES: To assess the role of anti-heart antibodies (AHA) in postpericardiotomy syndrome (PPS) and the timing of their appearance in relation to the initial manifestations of PPS. DESIGN AND SUBJECTS: Twenty patients who were scheduled to undergo elective coronary artery bypass grafting (CABG) were enrolled in a prospective, longitudinal pilot study. METHODS: Serum was sampled for AHA on the day prior to surgery and at regular intervalsfollowing surgery in all patients. In those who developed PPS, the serum AHA was determined on the day that typical clinical manifestations of PPS appeared and at regular intervals following the onset of PPS. RESULTS: All patients were negative for AHA on the day precedingsurgery. Three(15%) patients developed PPS. Their sera were negative for AHA on the day they were diagnosed as sufferingfrom PPS and the sera became positive for AHA within 14 days from the time of diagnosis. The intensity of immunofluorescence decreased markedly 30 days afterwards and AHA had disappeared within 90days after diagnosis of PPS. The other 17 (85%) patients were negative for AHA prior to surgery and remained so during the six-month postoperative follow-up period. CONCLUSION: The findings of this study suggest that serum AHA may not play a causal role inthe pathogenesis of PPS, but may rather be an epiphenomenon, reflecting an immune response to pericardial and/or myocardial injury.  相似文献   
96.
97.
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency.  相似文献   
98.
In vitro excystation studies were done on the metacercarial cysts of Ribeiroia ondatrae obtained from naturally infected leopard frogs, Rana pipiens. Studies were done in Petri dish cultures in various media maintained at 41°C. The media consisted of 0.5% trypsin—0.5% bile salts in Earles balanced salt solution at pH 7.8 (TB), 1% acid pepsin (AP) in 0.85% saline adjusted to pH 2 with HCl; acid saline (AS) adjusted to pH 2 with HCl, and saline (S). The TB medium, used successfully to excyst the metacercariae of numerous species of digeneans, did not induce excystation of Ribeiroia ondatrae. Some excystation occurred in AS but not in S. Excystation was 100% in AP with most organisms excysting within 30 s after placement in the medium at 41°C. Excystation in vitro in AP at 41°C is compatible with the fact that this organism establishes itself in the acid-pepsin environment of the proventriculus of avian hosts.  相似文献   
99.
In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus.  相似文献   
100.
Placental malaria caused by Plasmodium falciparum is a public health concern in tropical countries. Peripheral blood smears to detect placental malaria are often negative, and recrudescences are common during pregnancy. We performed placental histology on a series of first-time mothers delivering in an area endemic for P falciparum. A single nidus of malaria-infected erythrocytes was identified by placental histology in a single intervillous space from a woman who had no other evidence of peripheral or placental blood parasitemia. This finding suggests ring stage-infected erythrocytes sequester in vivo, or P falciparum can persist as a dormant blood stage form.  相似文献   
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