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Contrast enhancement during the dynamic MR imaging is important for the detection and characterization of focal liver lesions. The purpose of this study was to determine whether or not a timing examination with a injection of a 1.0-mL bolus of gadopentetate dimeglumine into the antecubital vein followed by rapid dynamic scanning and measurement of signal intensity of the aorta could help to obtain proper arterial-dominant phase images for the characterization of focal hepatic lesions during subsequent multiphase dynamic MR imaging. The imaging delay to acquisition of the first gadolinium-enhanced image for multiphase dynamic MR imaging was set to equal the time to peak aortic enhancement during the test examination. The first contrast-enhanced images of 80 patients with 160 focal liver lesions (hepatocellular carcinoma, n = 79; cavernous hemangioma, n = 51; metastatic tumor, n = 30) were then retrospectively reviewed. Peak aortic enhancement occurred between 10 and 28 seconds (mean, 16.5 seconds +/- 3.1) after starting the infusion of contrast material in 80 patients during the test-examination. Depending on the findings of intrahepatic vascular enhancement on the full-scale dynamic images, hepatic arterial phase (n = 11, 14%) or sinusoid phase (n = 65, 81%) imaging was obtained during the first gadolinium-enhanced acquisition in 76 (95%) of 80 patients. Three different lesions were well characterized and easily distinguished from each other (p < .0001) on the first-phase images depending on their enhancement pattern. In the majority of patients, timing examination with test-bolus injection was helpful in obtaining qualified images for the characterization of various focal lesions. 相似文献
13.
Five hundred allergy clinic patients were prick skin tested with papain, 1 mg/mL, in addition to usual local aeroallergens. Five of 475 subjects with seasonal allergic disease had positive skin tests to both papain and local pollens. None of the 25 individuals with negative skin test to pollens had skin reactivity to papain. The five subjects with positive skin tests to papain underwent double-blind placebo-papain challenges. All papain challenges were positive. Placebo challenges were negative. Papain-induced symptoms included palatal itching, watering itchy eyes, sneezing, rhinorrhea, abdominal cramps, diarrhea, and diaphoresis. Circulating papain-specific IgE was detected in all the papain-sensitive individuals, but not in control subjects. Confirmed papain sensitivity occurred in 1.05% of allergic subjects. In the papain-sensitive patients, cross-reacting antibodies with chymopapain were found. The small number of non-allergic subjects did not show any papain or chymopapain sensitivity in vitro. 相似文献
14.
Radiologic findings of Mirizzi syndrome with emphasis on MRI 总被引:6,自引:0,他引:6
We have reported a case of Mirizzi syndrome preoperatively diagnosed using MR cholangiopancreatography. MRCP and T2-weighted image using a single-shot fast spin-echo sequence accurately depicted all components of Mirizzi syndrome, including impacted stone in the neck of the gallbladder compressing the common hepatic duct and wall-thickening of the gallbladder without any evidence of malignancy. The combination of MRCP and T2-weighted image can be counted on to replace conventional modalities of diagnosing Mirizzi syndrome without any loss of diagnostic accuracy. 相似文献
15.
A patient complying with the clinical criteria for brain death was studied by preenhanced computed tomography (CT). Preenhanced CT showed apparent increased density at the base of the brain along the course of the major arterial vessels, and abnormally dense-appearing deep venous structures, like those of contrast-enhanced CT. There was a diffuse decrease in brain density with a poorly delineated ventricular system. These CT findings were very characteristic. CT as a non-invasive method seems to be valuable in the diagnosis of brain death. The relevant literature is reviewed and mechanisms showing those CT findings are discussed. 相似文献
16.
Reaction of diene alcohol5 and maleic anhydride in benzene at either room temperature or reflux proceeds probably through a intermolecular Diels-Alder cycloaddition followed by lactone formation to give adduct6. 相似文献
17.
Pil Whan Yoon Jong Yeal Kang Chul-Ho Kim Soong Joon Lee Jeong Joon Yoo Hee Joong Kim Sung Keun Kang Ju Hyeon Min Kang Sup Yoon 《Clinics in Orthopedic Surgery》2021,13(1):37
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events. 相似文献
18.
Hwan Bae Lee Jong Hwan Kwak Ok Pyo Zee Seung Jo Yoo 《Archives of pharmacal research》1994,17(4):273-277
Six flavonoids were isolated from the aerial parts ofCirsium rhinoceros. The flavonoids were identified as apigenin, luteolin, pectolinarigenin-7-O-β-D-glucopyranoside, linarin, pectolinarin and hispidulin-7-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside on the basis of chemical and spectral evidence. 相似文献
19.
For the restoration of thumb opposition many types of tendon transfer techniques have been described. The flexor digitorum superficialis (FDS) of the ring finger is commonly selected as a motor. On occasion, however, the quality of the flexor muscles of the fingers or wrist is not good enough for tendon transfer and another available muscle must be selected. In this situation, we have preferred to use an extensor carpi radialis longus (ECRL) or brevis (ECRB) transfer to restore opposition of the thumb. Follow-up examination, at an average 5 years and 10 months after operation, showed that the results of ten of 11 transfers were excellent and the other was good. 相似文献
20.
The publication rates of presentations at major Spine Specialty Society meetings (NASS, SRS, ISSLS) 总被引:2,自引:0,他引:2
STUDY DESIGN: A review of all the presentations at three major spine specialty meetings held over a 3-year period. OBJECTIVES: To determine the rate of publication in peer-reviewed journals after presentations at major spine meetings conducted annually by the following three organizations: North American Spine Society (NASS), Scoliosis Research Society (SRS), and International Society for the Study of the Lumbar Spine (ISSLS). SUMMARY OF BACKGROUND DATA: The rate of publication for presentations at national and international meetings has been determined for medical and surgical subspecialties. This rate has been used to judge the quality of the content of the meetings and to determine the validity of the research presentations. METHODS: All presentations either in poster or oral presentation form were entered into a database covering a 3-year period for spine specialty meetings conducted annually by the following three organizations: NASS 1990 to 1992, SRS 1991 to 1993, and ISSLS 1991 to 1993. A computer search for each abstract was performed with the Melvyl Medline Plus database to determine if the abstract had been published in a peer-reviewed journal from 1990 to the end of 1997. Publication rates for presentations at these three meetings were determined over a 3-year period. RESULTS: A total of 1186 abstracts were listed over a 3-year period in the final programs of these three meetings for the years 1991 to 1993 (SRS, ISSLS) and 1990 to 1992 (NASS). Of these 1186 abstracts, 516 were published in peer-reviewed journals, giving an overall publication rate of 43.5%. The publication rates for the three different meetings (NASS, SRS, ISSLS) were similar, with values of 40%, 47%, and 45% respectively. More than 90% of the publications resulting from these meetings were published within a period of 4 years from the data of the meeting. CONCLUSIONS: The publication rates of presentations at three major spine specialty meetings are high and quite comparable with the publication rates of meetings in other medical subspecialties. This reflects the high quality of the meeting programs and validates their selection process. 相似文献