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排序方式: 共有395条查询结果,搜索用时 15 毫秒
71.
CT- and US-guided biopsy of the pancreas 总被引:15,自引:0,他引:15
72.
Spontaneous perinephric and subcapsular renal hemorrhage: evaluation with CT, US, and angiography 总被引:10,自引:0,他引:10
Eighteen consecutive patients with acute spontaneous perinephric hemorrhage were examined with computed tomography (CT) (n = 18), ultrasonography (US) (n = 15), and angiography (n = 9). Renal cell carcinoma was found in 10 patients; angiomyolipoma, three; and segmental renal infarction, arteriovenous malformation (AVM), hemorrhagic cyst, abscess, and idiopathic hemorrhage, one each. Initial CT examinations demonstrated the extent of hemorrhage in all cases and a distinct mass in 12 (67%), with CT characteristics suggestive of the correct diagnosis in 11. In the other six patients (33%), a discrete mass was not seen at initial CT, and in five cause of hemorrhage was not clear. Two of the five underwent follow-up CT, which correctly demonstrated carcinoma in both. Overall, CT findings suggested the correct diagnosis in 14 patients (78%). US was sensitive for detection of an abnormality but nonspecific as to its nature. Angiography demonstrated unsuspected AVM in one patient, segmental renal infarction seen at CT in one, but only one of five carcinomas suspected at CT. Data from this study suggest that CT is the most valuable examination for patients with spontaneous renal hemorrhage. 相似文献
73.
74.
Edelman RR; Wedeen VJ; Davis KR; Widder D; Hahn P; Shoukimas G; Brady TJ 《Radiology》1986,161(3):779-783
A new technique is described that allows for the creation of pure pulsatile flow magnetic resonance (MR) images in a single acquisition. Five to 16 electrocardiographically gated images spanning the entire cardiac cycle are obtained with use of a gradient-echo pulse sequence. The section can be varied from 4 mm thick to full thickness projection. Taken singly, each image provides direct assessment of flow direction and velocity. Subtraction of image pairs eliminates signal detected from stationary protons, producing images of pulsatile flow. In this study the technique was used to image the flow of cerebrospinal fluid (CSF) in healthy subjects and in one patient with syringohydromyelia. The data suggest that multiphasic MR imaging provides a powerful means for the noninvasive assessment of CSF pulsatile flow dynamics and may have potential clinical application for the investigation of a variety of abnormalities such as normal pressure hydrocephalus, syrinx, and spinal block. 相似文献
75.
Fourteen patients with abnormal subdiaphragmatic fluid collections (eight intraperitoneal, two extraperitoneal, and four intra- and extraperitoneal) were examined with computed tomography (CT) and magnetic resonance (MR) imaging. MR and CT provided equivalent information concerning the presence and extent of fluid collections in 13 of the 14 cases. Image acquisitions with two different repetition times (TRs) and two echo times (TEs) were necessary, in most cases, to detect and discriminate between different types of pathologic fluids. Transudative ascites demonstrated long T1 and T2 relaxation times, whereas abscesses, phlegmon, pancreatic pseudocyst, exudative pancreatitis, and chronic hematoma demonstrated an intermediate or short T1 and a long T2. 相似文献
76.
77.
Evaluating community health worker performance in India 总被引:1,自引:0,他引:1
BHATTACHARJI SARA; ABRAHAM SULOCHANA; MULIYIL JAYAPRAKASH; JOB JAYAKARAN S; JOHN KR; JOSEPH ABRAHAM 《Health policy and planning》1986,1(3):232-239
In 1977 the Government of India launched a health care experimentin which volunteers were used to provide a basic health careservice. Community health workers have also been used in manysmall, non-governmental programmes. Although much has been saidabout the selection and training of such workers, there havebeen very few attempts to evaluate their actual work performance.This paper makes the plea for more, regular evaluations of theiractivities by those involved in the programmes: communities,supervisors and health workers themselves. Such evaluationsare useful even if they are only done on a small scale. Whatis described here is a small study of the performance of part-timecommunity health workers (PTCHWs) in a programmme initiatedin 1977 by the Community Health Department of the ChristianMedical College in Vellore, South India. It concludes that thePTCHWs with the highest performance scores have, on the whole,less education, more experience, less population to cover andmore intense supervision. 相似文献
78.
79.
Developmental biology of the dendritic cell system 总被引:1,自引:0,他引:1
Aim : To determine whether an imbalance of dendritic cell subsets might contribute to diminished adaptive host responses observed in newborn infants. It was hypothesized that the proportion of lymphoid dendritic cells would be greater than that of myeloid dendritic cells in cord blood. Methods : To investigate this, dendritic cell subsets were evaluated in whole cord blood by flow cytometry. Circulating dendritic cells were also isolated from cord blood based on CD1c and BDCA-2 expression. Myeloid dendritic cells were also obtained by culturing cord and adult blood monocytes. Surface phenotypes of these cells were determined by flow cytometry using monoclonal antibodies directed against lineage, major histocompatibility, adhesion, co-stimulation and cytokine receptor molecules. Antigen-presenting functions of dendritic cell subsets were determined by mixed leukocyte reactions. Results : Circulating myeloid dendritic cells were higher in cord blood than previously reported in adult blood, whereas lymphoid dendritic cell numbers were similar between cord and adult blood. Expression of CD11c, CD45RA and CD45RO did not accurately differentiate between dendritic cell subsets circulating in cord blood. Fresh and culture-derived cord blood myeloid dendritic cells stimulated adult allogeneic leukocyte proliferation, while lymphoid dendritic cells were less effective inducers of an adult allogeneic leukocyte response. Culture-derived dendritic cells induced modest autologous cord blood leukocyte proliferation, but freshly isolated myeloid and lymphoid dendritic cells did not stimulated autologous leukocytes.
Conclusion : Contrary to the hypothesis, an imbalance in the ratio of circulating myeloid to lymphoid dendritic cell subsets does not exist and, therefore, does not contribute to diminished adaptive immune responses in newborn infants. 相似文献
Conclusion : Contrary to the hypothesis, an imbalance in the ratio of circulating myeloid to lymphoid dendritic cell subsets does not exist and, therefore, does not contribute to diminished adaptive immune responses in newborn infants. 相似文献
80.
DD Suh CC Yang Y Cao JR Heiman PA Garland KR Maravilla 《Journal of psychosomatic obstetrics and gynaecology》2013,34(2):153-162
We utilized contrast enhanced magnetic resonance imaging (MRI) to delineate the anatomy of the female genital and pelvic organs during sexual arousal. Eleven healthy pre-menopausal women and eight healthy post-menopausal women underwent MRI of the pelvis while watching an erotic video. A 1.5 Tesla MR system was used to produce T1-weighted images following administration of MS-325, a gadolinium-based blood pool contrast agent. Selected structural dimensions and enhancement were measured prior to and during sexual arousal. In both pre- and post-menopausal subjects, vestibular bulb and labia minora width increased with arousal. Enhancement measurements increased in the bulb, labia minora and clitoris in both pre- and post-menopausal subjects, and in the vagina in pre-menopausal subjects. There were no marked changes in size or enhancement of the labia majora, urethra, cervix, or rectum during sexual arousal in pre- or post-menopausal subjects. Using MRI, we observed specific changes in the female genitalia and pelvic organs with sexual arousal, in both pre- and post-menopausal women. MRI can potentially provide detailed anatomical information in the assessment of female sexual function, particularly with regard to changes in blood flow. 相似文献