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1.
A total of 18 patients with clinical suspicion of a pancreatic tumor underwent dynamic contrast-enhanced CT and MRI examinations. A fat-suppressed T1-weighted 2D fast-low-angle-shot (FLASH) sequence and a T2-weighted spin-echo (SE) sequence were applied in a transverse orientation using a circularly polarized (CP) body phased-array coil. The FLASH sequence was repeated after Gd-DTPA administration. The highest spatial resolution was 1.37 x 1.37 x 3.00 mm3. In two cases a half Fourier single-shot turbo-SE sequence (HASTE) was additionally applied. In a comparison between CT and MRI, pancreatic masses could be demonstrated and characterized with excellent image quality. The fat-saturated 2D FLASH sequence yielded the highest contrast-to-noise ratios after Gd-DTPA administration between pancreas and inflammatory or neoplastic lesion. One non-contour deforming carcinoma could be detected only with MRI and was only retrospectively visible on CT with an element of uncertainty. Magnetic resonance imaging using a CP body phased-array coil and fat-suppressed T1- and T2-weighted FLASH, SE, and turbo-SE sequences offers diagnostic possibilities in improved imaging of the pancreas.  相似文献   

2.
PURPOSE: The aim of this study was the assessment of atresia formation after syngeneic fetal small bowel transplantation (SBTx) to clarify its pathogenesis. METHODS: Seventy Lewis rat fetuses (gestational age, 18 to 19 days) were obtained by hysterotomy, and a 30-mm long section of small bowel was excised from each fetus. Each bowel graft was then transplanted into the space between the peritoneum and the rectus abdominis in 70 adult Lewis rats to expose the grafts to ischemic stress. Transplantation was successful in 63 of 70 grafts (90%). Successfully transplanted bowel grafts were harvested for macroscopic and microscopic examination 10 days posttransplantation. RESULTS: Of the successfully transplanted grafts, only two (3%) were atresia free; 127 atretic segments were found in the remaining 61 grafts. Twenty-four grafts (38%) had a single atresia comprised of membranous stenosis (MS) in two, membranous atresia (MA) in 10, and blind ends (BEs) with or without a connecting tissue remnant in 12. Thirty-seven grafts (59%) had multiple atresias, comprised of MS, MA, or both in six, BEs alone in seven, and a combination of BEs with MS or MA in 24. CONCLUSIONS: Our model is the first to succeed in inducing experimentally membranous stenosis and a high incidence (59%) of multiple atresias. These results suggest that bowel ischemia is responsible for multiple bowel atresia formation.  相似文献   

3.
OBJECTIVE: To report the application of dynamic contrast-enhanced subtraction MRI for detecting recurrences in aggressive or malignant soft tissue tumors. DESIGN: The imaging studies consisted of static (T1- and T2-weighted spin-echo) acquisitions, followed by dynamic conventional spin-echo short TR/TE images (at 45 s, 1 min 30 s and 5 min) after a bolus of intravenous contrast medium. Contrast images were subtracted from the precontrast scan on the console. PATIENTS: Ninety-eight patients were studied who had had aggressive or malignant soft tissue tumors treated by surgery, and were followed up to assess recurrences. RESULTS: Subtraction MRI characterized recurrences better than routine sequences in 10 patients (1 lesion was seen only with this technique, 6 were better delineated, and 3 inflammatory pseudotumors were identified), and less well in 4 cases. CONCLUSION: As the number of levels studied on dynamic images is limited, and all but one recurrence were detected on T2-weighted images, it remains logical to start the examination with T2-weighted spin-echo images, and to use the dynamic study only if contrast injection is required.  相似文献   

4.
The aim of this study was to compare the diagnostic performance of contrast-enhanced fast multiplanar gradient-echo (GRE) and T2-weighted fast spin-echo (FSE) image sets in the assessment of uterus, cervix, and vagina. Fast (up to 20 contiguous sections in 23 s) multiplanar GRE and FSE images of 45 patients referred for imaging of the female pelvis were evaluated retrospectively with regard to overall image quality and the ability to detect normal anatomic structures, as well as lesion conspicuity. Results were compared with histologic findings (n = 29) or clinical follow-up. Furthermore, a quantitative assessment of contrast-to-noise ratios among normal uterine and cervical structures as well as uterine lesions was performed for both sequences. On GRE images, uterine and cervical differentiation was best seen on the image sets acquired 15 and 60 s following contrast enhancement and results were significantly better compared with delayed images (p < 0.05). Delineation of the junctional zone was significantly (p < 0.05) better on FSE compared with GRE images; no significant difference was seen for the other anatomic structures. Overall image quality of GRE and FSE images was similar. Sensitivity for lesion detection based on both GRE and FSE images was 96% with a sensitivity of 93% for GRE, and 81% for FSE images alone, respectively. Using the extended McNemar chi 2 test, the difference in diagnostic performance between FSE and GRE revealed no significant difference, whereas the combination of both techniques performed better than FSE imaging alone (p < 0.05). The presented data suggest that dynamic contrast-enhanced GRE imaging should be part of an MR examination of the female pelvis. Combined GRE and FSE imaging provide an excellent sensitivity in the assessment of uterine and vaginal pathologies.  相似文献   

5.
A carboxylesterase [2,3,4,6-tetra-O-acetyl-1-[(N-acetyl-N-phenylamino)oxy]-1-deoxy-beta-D-g lucopyranoside (GPA) O-deacetylase] from a culture product of Aspergillus oryzae (Taka diastase) was purified 8500-fold with a yield of 3%. The molecular mass of the purified enzyme was shown to be 35 +/- 1 kDa by SDS/PAGE. The enzyme shows a selective O-deacetylation activity of GPA to give the fully O-deacetylated glucoside. Among the substrates tested, the enzyme did not hydrolyze benzoyl and phenylacetyl esters and acetamides. In the hydrolysis of p-nitrophenyl esters, the acyl preference is acetyl > propionyl > butyryl, judging from the Vmax/Km values. A good correlation between log(Vmax/Km) and the Taft's Es constant of the alkyl group of the acyl moiety was obtained. The optimum pH was around 7.3 at 37 degrees C, and the enzyme was inhibited by mercuric chloride, p-chloromercuribenzoate and diisopropyl fluorophosphate. This enzyme should be useful for the selective removal of acetyl groups that serve to protect hydroxyl groups during carbohydrate synthesis.  相似文献   

6.
BACKGROUND: The use of surface coils for magnetic resonance imaging (MRI) allows enhanced image definition and so potentially more accurate staging of colorectal cancer. Endorectal coil imaging is invasive, operator dependent and impossible in a high proportion of patients due to rectal stricture. The phased-array pelvic coil, however, is non-invasive and applicable to all rectal tumours. METHODS: A pelvic phased-array coil was used for preoperative MRI staging of 38 primary rectal carcinomas. Results were expressed according to the Dukes and tumour nodes metastasis (TNM) classifications. After resection of the tumour, the stage predicted on MRI was compared with the pathological classification. RESULTS: The overall accuracy of preoperative staging with the pelvic phased-array coil was 55 per cent for both Dukes class and T stage. Assessment of nodal involvement gave an overall accuracy for MRI of 76 per cent with a sensitivity of 57 per cent and specificity of 88 per cent. CONCLUSION: Use of a pelvic phased-array coil did not improve the staging accuracy of MRI to a clinically useful level.  相似文献   

7.
Cervical and uterine varices with thrombosis were observed at the necropsy of a virgin 16-year-old Peruvian Paso that had previous episodes of hemorrhage from the uterus. Practitioners and pathologists should be alert to the possibility of ruptured varices in mares with hemorrhage into the uterus or from the vulva.  相似文献   

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We report a case of placenta percreta diagnosed by ultrasound and color doppler image at the fourteenth week of gestation. Initial approach was a trial of IM methotrexate followed by total hysterectomy, during which was observed a rupture of the uterus with the adherence of the placenta to the posterior region of the bladder. We also present a literature review on the incidence of placenta percreta, etiology, diagnosis, treatment, and complications.  相似文献   

10.
Routine anaerobic culture of urine identified the urinary tract as the primary focus of sepsis in a postoperative patient with Bacteroides fragilis septicaemia. Specimens of urine from six other symptomatic patients grew > 10(8) cfu/litre of a Bacteroides species in pure growth. The significance of these isolates is discussed. Multipoint technology and the availability of anaerobic work stations have facilitated anaerobic culture and reduced its cost. The incorporation of anaerobic culture of urine into routine laboratory practice may be clinically valuable and should be considered.  相似文献   

11.
The objective of the present study was to evaluate the safety and efficacy of gadodiamide injection, a non ionic MRI contrast medium in comparison with the ionic agent gadopentate dimeglumine. Two groups of 50 patients with known or suspected lesions of the brain or head and neck were enrolled in a double -blind, randomised trial. In the gadopentate dimeglumine group three patients reported four adverse events, and in the gadodiamide injection group, four patients reported four side effects. All events were minor. Two radiologists analyzed pre and post-contrast MR images. The parameters evaluated were the number of lesions, delineation of the lesion, gain of diagnostic information, and final diagnosis. Both contrast media gave identical diagnostic information.  相似文献   

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A higher frequency of complications has been observed among pregnant women with IUDs in situ. These complications include maternal death (more frequently observed among users of the Dalkon shield), ectopic pregnancy, spontaneous abortion, and partus immaturus or prematurus. Partus prematurus or immaturus was observed in 7 of 19 pregnant women with IUDs in situ observed in the Wilhelmina Clinic. In 6 of these cases, the birth began with premature rupture of the amniotic sac, probably caused by the IUD. Pregnancy in IUD patients should be diagnosed as soon as possible. The IUD should be removed by gentle pressure on the control thread, if possible. If the IUD remains in situ, the woman and her partner should be thoroughly informed of the possible risks of the pregnancy. If it is decided to carry the pregnancy to term, frequent control check-ups should be given and the patient should be thoroughly instructed of possible symptoms of complications.  相似文献   

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We report a case with an unusual müllerian anomaly: complete uterine septum and pyometra in the right hemicavity and pyocolpos along with a longitudinal vaginal septum. A patient with recurrent low-grade fever and lower abdominal pain was admitted. Pyometra and pyocolpos were detected in the right uterine hemicavity and in the right hemivagina. The septa were resected, the cavities were irrigated, and the patient was treated with antibiotics. The patient conceived 8 months later. Patients with abnormal vaginal findings should be approached with caution; precise knowledge of urogenital anatomy and urogenital anomalies is necessary in the management of these patients.  相似文献   

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The purpose of this study was to demonstrate that it is possible to continuously monitor the gastrointestinal transit of magnetically marked, solid, oral dosage forms with multichannel biomagnetic measuring equipment and by magnetic source imaging (MSI) methods. For the investigations presented, a sucrose pellet was coated with powdered magnetite (Fe3O4) in poly(methyl methacrylate). Then, the pellet was enclosed in a capsule prepared from silicone rubber and magnetized to obtain a net magnetic dipole moment. After ingestion of the capsule, its magnetic field distribution over the abdomen was recorded for several time intervals with a 37-channel superconducting quantum interference device (SQUID) magnetometer. At each time point, the position of the capsule within the gastrointestinal tract was calculated from the measured field distribution, assuming a magnetic dipole model. The data presented here demonstrate that with this noninvasive method of magnetic marker monitoring it is possible to investigate the gastrointestinal transit of a solid oral dosage form with a temporal resolution in the order of milliseconds and a spatial resolution within a range of millimeters.  相似文献   

18.
Hodgkin's disease has rarely been reported to occur subsequent to a previous non-Hodgkin's lymphoma, usually of B-cell type and with a 5 to 7-year median interval between diagnoses. Even rarer is the finding of residual non-Hodgkin's lymphoma at the time of Hodgkin's disease diagnosis. Six such cases have been reported, with five of the six representing "discordant" lymphomas and the other one a "composite" lymphoma. Only four of the six cases (all discordant lymphomas) were supported by immunohistochemical studies; flow cytometric immunophenotyping has not been performed in any of the reported cases. We report a nodal composite lymphoma (B-cell non-Hodgkin's lymphoma and Hodgkin's disease, mixed cellularity), supported by flow cytometric immunophenotyping and immunohistochemical studies, occurring in a patient 5 years after a diagnosis of B-cell non-Hodgkin's lymphoma. This report emphasizes the application and usefulness of flow cytometric immunophenotyping and immunohistochemical studies in such cases.  相似文献   

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High-resolution CT (HRCT) is a technique developed over the last decade. It optimises spatial resolution and provides details similar to those obtainable from gross pathologic specimens. HRCT of the lungs provides an accurate assessment of the pattern and distribution of many disease processes that in the conventional chest radiograph are occult or non-specific. HRCT is an established technique and the method of choice for evaluating a variety of pulmonary diseases. In this review we describe the modifications in CT technique that are instrumental in obtaining HRCT, and we also give examples of normal and pathologic findings in general.  相似文献   

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