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61.
Non-traumatic stereotyped postictal purpura is rare. A 25-year-old woman presented with right facial, cheek and periorbital purpuric eruptions that occurred after secondarily generalized tonic-clonic seizures. The stereotyped, invariably right-sided facial skin eruption, which resolved in 48 hours, falsely raised concerns of spousal abuse. Possible pathophysiological mechanisms include: (a) valsalva-induced capillary hypertension with secondary purpura, (b) ictal corticolimbic stimulation of the autonomic nervous innervation of facial vasomotor structures, and (c) trigeminal-mediated local release of vasoactive substances. Although rare, such stereotyped patterns of purpura should be recognized to avoid incorrect attribution of spousal abuse. 相似文献
62.
SO Trerotola MS Johnson H Shah MA Kraus MA McKusky WT Ambrosius VJ Harris JJ Snidow 《Canadian Metallurgical Quarterly》1998,207(2):491-496
OBJECTIVE: The purpose of this study was to determine the feasibility of high-resolution sonography for the detection of meniscal cysts and associated meniscal tears and for the differentiation of meniscal cysts from other masses at the knee joint. SUBJECTS AND METHODS: Fifty consecutive patients (51 knees) with a palpable mass at the knee joint were examined prospectively using a 7.5-MHz annular array transducer. Mass consistency and location and meniscal integrity were evaluated. Sonographic findings were correlated with surgery (46/51) and histopathology (15/51). Five patients did not undergo surgery. RESULTS: At surgery, 32 masses appeared to be meniscal cysts, whereas 19 were other types of masses. Sonographically, 31 of the 32 meniscal cysts were diagnosed correctly. Sonographic differentiation of the other types of masses from meniscal cysts could reliably be made in 17 of 19 cases; two masses were falsely interpreted as meniscal cysts. Sensitivity, specificity, and accuracy of sonography in the depiction of meniscal cysts were 97%, 86%, and 94%, respectively. The positive predictive value was 94% and the negative predictive value was 92%. Meniscal tears (31/46) and meniscal tears concomitant with meniscal cysts (26/32) were detected with an accuracy of 83% and 88%, respectively. CONCLUSION: Sonography is an accurate imaging technique for the detection of meniscal cysts and associated meniscal tears. Differentiation of meniscal cysts from other cystic and solid masses at the knee joint can be reliably made with sonography. 相似文献
63.
JM Barkmeier SO Trerotola EA Wiebke S Sherman VJ Harris JJ Snidow MS Johnson WJ Rogers XH Zhou 《Canadian Metallurgical Quarterly》1998,21(4):324-328
p27kip1 (p27) protein is an inhibitor of cyclin and cyclin-dependent kinase complexes and prevents progression of cells from G1 to the S phase of the cell cycle. p27 might have tumor suppressor activity, and decreased p27 expression is associated with aggressive tumor behavior in several human malignancies. The object of this study was to evaluate p27 expression in prostatic adenocarcinoma treated by radical prostatectomy and to assess its association with numerous morphologic and clinical features. One hundred thirty-eight prostatic adenocarcinomas were evaluated for p27 expression by quantifying nuclear immunohistochemical staining. p27 expression was tested for association with patient age, family history of prostate cancer, preoperative serum prostate-specific antigen level, Gleason score, extraprostatic extension, seminal vesicle involvement, lymph node metastases, tumor-node-metastasis stage, DNA ploidy by flow cytometric analysis, and subclinical biochemical failure. p27 expression was analyzed as a continuous variable, and we also classified the tumors as low expressors (< 50% of cells p27 positive) or high expressors (> 50% of cells p27 positive) for comparison. Patients with adenocarcinomas that exhibited low p27 expression had higher mean Gleason scores than did high expressors (7 vs. 6.2, respectively; P = .002). Low p27 expression correlated with positive surgical margins (P = .05), seminal vesicle involvement (P = .007), lymph node metastasis (P = .03), and aneuploid cancers (P = .003), but it did not correlate with subclinical biochemical failure. p27 expression correlated with a number of prognostic morphologic features in prostatic adenocarcinoma, and the evaluation of p27 expression might provide additional prognostic information. 相似文献
64.
A predisposition for high or low levels of serum marker concentrations in second trimester Down syndrome screening reflecting itself in consecutive pregnancies in the same woman has been demonstrated, but hitherto the possible effect of including previous marker results in a current risk evaluation has been considered negligible. Using published data on correlations between the markers AFP, hCG and uE3 in different normal pregnancies in the same women and age-related a priori probabilities we found, that in triple marker screening the inclusion of results from a previous pregnancy in a likelihood ratio based risk calculation could increase the detection rate for women having had an earlier pregnancy from 68.0 per cent to 70.2 per cent at a risk cut-off = 1:250. The screen positive rate for normals for the same population of women, being on average older than the total population, fell from 7.1 per cent to 6.8 per cent. These figures, that are based on an assumption of the same correlations between one normal and one Down syndrome pregnancy as between two normal pregnancies, corresponds to an expected reduction, in the population considered, of the number of children born with Down syndrome of 6.7 per cent and of the number of screen positive normals of 4.7 per cent. Considering that this can be achieved at no extra cost, it is concluded that implementation of a procedure for taking information from previous pregnancies into account in second trimester screening should be considered at centres that can handle the software problems involved in doing so. However, better data on the correlations between a normal and a subsequent Down syndrome pregnancy in the same woman should probably be awaited before this is done. 相似文献
65.
66.
Dermatomyositis is a rare inflammatory myopathy with characteristic skin manifestations and muscular weakness. The disease can be categorized as adult idiopathic, juvenile, or amyopathic dermatomyositis as well as that associated with a connective tissue disease or a malignancy. Immunologic factors are most likely involved in the pathogenesis of the disease; however, genetic and environmental issues may also play important roles. Treatment with immunosuppressive agents has proved successful in the majority of patients, although significant morbidity still occurs. 相似文献
67.
A large body of data suggest that brain cholecystokinin (CCK) systems are involved in the regulation of anxiety, and numerous studies have demonstrated that CCK-4, a CCKB agonist, reliably induces panic attacks in patients with panic disorder. Recently, pentagastrin, a commercially available CCKB agonist, has been reported to have similar anxiogenic properties. To further explore the utility of pentagastrin as a challenge agent and to determine whether its effects are dose-related, a dose-response study was conducted in ten healthy volunteers. Pentagastrin (0.2 microgram/kg, 0.6 microgram/kg and 1.0 microgram/kg) and inactive placebo were infused over one minute on four separate challenge days in a double-blind fashion. Subjects received pentagastrin while participating in a structured social interaction task. Repeated measures of anxiety, blood pressure, pulse, ACTH, and cortisol were taken at baseline and postinfusion. Pentagastrin administration led to increases in anxiety, pulse, ACTH, cortisol and physical symptoms of panic, in a dose-related manner. Participation in the social interaction task led to increases in measures of anxiety as well as increases in pulse and blood pressure. Few differences were found between the 0.2 microgram/kg dose of pentagastrin and placebo, or between the 0.6 microgram/kg and the 1.0 microgram/kg doses of pentagastrin. These findings support the notion that CCK systems are involved in the regulation of anxiety, and suggest that the 0.6 microgram/kg dose may be optimal for increasing symptoms of anxiety while minimizing unpleasant side effects. The powerful anxiogenic effects of the social interaction task underscore the importance of contextual variables in challenge studies. 相似文献
68.
Intracerebral infection of mice aged 2-3 days with hepatitis C virus (HCV) from chronically infected suckling mouse brain cultures and porcine embryo cells resulted in the death of animals after 12-14 days. Repeated passages of HCV in animals decreased the incubation period to just 3-4 days. Blood serum of surviving mice collected during the 4th week postinfection contained antiHCV antibodies detected by enzyme immunoassay and hemagglutination inhibition test. The results are proof of creation of a new in vivo model of experimental HCV infection. 相似文献
69.
Acute choroidal ischemia as a complication of photocoagulation 总被引:2,自引:0,他引:2
MH Goldbaum SO Galinos D Apple GK Asdourian K Nagpal L Jampol MB Woolf B Busse 《Canadian Metallurgical Quarterly》1976,94(6):1025-1035
Acute choroidal vascular insufficiency as a complication of photocoagulation has been little noticed. In 17 eyes of 16 patients photocoagulated with either xenon or argon sources for proliferative sickle cell retinopathy, gray lesions of the fundus developed peripheral to the photocoagulation sites. Histologic examination of similar gray lesions produced in monkeys showed necrosis and atrophy of the outer half of the retina. Intense photocoagulation of the human fundus, even with smaller spot sizes, may occlude a choroidal artery, producing separate gray lesions of distinctive shape. The lesions in both the patients and the monkeys progressed to granular hyperpigmentation by two to three weeks after photocoagulation. 相似文献
70.
Thomas C. Grenfell Donald K. Perovich John A. Ogren 《Cold Regions Science and Technology》1981,4(2):121-127
Spectral albedos (αλ) from 380 to 2500 nm are reported for a snowpack in the Cascade Mountains of Washington. Data were obtained from just after an 0.4 m snowfall on 13 March 1980 until the pack had metamorphosed to melting coarse grains about 1 mm in diameter mixed with dust. Measurements were made under cloudy conditions to obtain a diffuse incident radiation field. Structural parameters of the snow were measured concurrently for all cases, and on three occasions, estimates of absorbing impurity content were obtained. The dependence of the spectral albedos of the snowpack on grain size and impurity content is illustrated. Comparison of wavelength-integrated albedos (αobs) obtained using Kipp and Zonen radiometers with corresponding albedos derived from αλ data show good agreement, and suggests a correlation between αobs and the amount of incident radiation transmitted by the cloud layer. Comparison with theoretical models confirms that impurities in the snow depress αλ at visible wavelengths but have little effect beyond 900 nm in the infrared; however, quantitative agreement with theory is uncertain at present. 相似文献