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991.
Paget disease of the spine: CT with clinical correlation   总被引:1,自引:0,他引:1  
Thirty-six patients with pagetic involvement of the spine were evaluated clinically and by computed tomography (CT). Pagetic phase, modeling expansion, degree and site of spinal stenosis, and pagetic facet joint arthropathy were recorded for each involved vertebral segment. CT demonstrated spinal stenosis in 20 patients, 11 of whom exhibited spinal stenosis on plain films. Twenty-one patients had symptoms of neck or back pain, with associated neurologic dysfunction in 13. Spinal stenosis was present in 81% of the symptomatic patients and 20% of the asymptomatic patients. Severe pagetic facet arthropathy was present in 17 of the symptomatic patients. We conclude that spinal stenosis is an important cause of vertebral pain and neurologic dysfunction.  相似文献   
992.
993.
A 48-year-old man presented with a vertical gaze palsy associated with secondary syphilis. It is suggested that the eye movement disorder is due to syphilitic endarteritis in the mesodiencephalic region.  相似文献   
994.
Magnetic resonance imaging of the orbit: a preliminary experience   总被引:2,自引:0,他引:2  
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995.
996.
At 37°C, fluorescein-conjugated anti-H-2 alloantibodies specifically induce, at the surface of living mouse lymphocytes, the redistribution of the corresponding H-2 antigens, which cluster as patches and sometimes single caps at one pole of the cell. This aggregation is inhibited at 0°C and the H-2 antigens, stained by fluorescent antibodies in the cold, appear evenly spread over the cell surface. This phenomenon was used to define the relationships between the membrane structures bearing the antigens coded by the H-2K and the H-2D genes of the H-2 region. Monospecific anti-H-2 antibodies coupled to either tetramethyl rhodamine isothiocyanate or fluorescein isothiocyanate were used to induce the redistribution of H-2D and H-2K antigens of the H-2b and H-2k haplotype at the surface of lymph node cells from homozygous and F1 hybrid mice. It was observed that the diffuse distribution of H-2K antigens labeled at 0°C was not affected by the prior antibody-induced aggregation of H-2D antigens and vice versa. The results were the same for H-2 antigens governed by genes located either in cis or in trans position. These data indicate that the H-2K and H-2D antigens migrate independently at the cell surface, and suggest that the gene products from the D and the K end of the H-2 region are expressed on independent molecules or structures at the cell membrane.  相似文献   
997.
998.
PURPOSE: To study the limits to a perfect ideal customized wavefront correction due to the change of aberrations during accommodation. METHODS. We measured the dynamic changes of ocular aberrations during accommodation in normal eyes with a real-time Hartmann-Shack wavefront sensor. Those results were used in computer simulations to predict the benefit of a perfect customized correction. RESULTS: Due to the continuous changes of the aberrations over time, an ideal perfect static correction will not provide stable aberration-free optics. For example, when the eye accommodates to near objects, due to the changing aberrations, the eye will become aberrated again. An alternative correction using the aberration pattern for a slightly accommodated condition could provide a better-correction in a larger accommodative range, although at the cost of non-perfect correction for far vision. CONCLUSIONS: Due to the dynamic nature of ocular optics, a static perfect correction, for instance performed in customized refractive surgery, would not remain perfect for every condition occurring during normal accommodation.  相似文献   
999.
OBJECTIVE: To determine the diagnostic value of transvaginal ultrasonography and hysteroscopy in patients with postmenopausal bleeding. MATERIAL AND METHODS: Between January 1, 1998 and June 30, 1999, 88 outpatient women with postmenopausal bleeding were enrolled in a prospective study. They underwent transvaginal ultrasonography and hysteroscopy, and were submitted to directed biopsy during hysteroscopy. Findings were classified as normal endometrium, suggestive of atrophy, focal abnormality (benign or suspicious), and diffuse thickness (benign or suspicious). Data was compared with the final diagnosis, established by histological examination, as atrophy, benign pathology, atypical hyperplasia and endometrial carcinoma. RESULTS: Among 88 women enrolled, 15 were excluded because hysteroscopy was impossible, and four had abandoned the study. The histological findings were scanty material in 12 (17.4%), atrophy in 24 (34.8%), cystic atrophy in one (1.4%), normal endometrium in five (7.2%), tuberculous endometritis in one (1.4%), polyps in 12 (17.4%), leiomyoma in one (1.4%), non-atypical hyperplasia in three (4.3%), atypical hyperplasia in one (1.4%) and endometrial carcinoma in nine cases (13.0%). For the assessment of endometrial carcinoma, ultrasonography revealed sensitivity 77.8%, specificity 93.3%, positive predictive value 63.6%, negative predictive value 96.6%; and hysteroscopy revealed sensitivity of 88.9%, specificity 98.3%, positive predictive value 88.9%, negative predictive value 98.3%. The combined use of both methods revealed sensitivity 100%, specificity 91.7%, positive predictive value 64.3%, negative predictive value 100%. CONCLUSIONS: Both imagiological methods were found to be useful screening tests for endometrial carcinoma. Hysteroscopy was a superior diagnostic procedure.  相似文献   
1000.
The nucleocapsid (N) protein of SARS-coronavirus (SARS CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membraneglycoprotein, In this study, the N protein of SARS-CoV was expressed in Escherichia coli DH5alpha and identified with pooled sera from patients in the convalescence phase of SARS.  相似文献   
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