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41.
Metastasizing meningioma 总被引:1,自引:0,他引:1
A very unusual case of metastatic spread of a meningioma is described. The clinical presentation was of extradural spinal cord compression, without evidence of a primary tumor. Computed tomography did not reveal any intracranial meningioma; the histopathology of the extradural spinal tumor was identical with that of two intracranial meningiomas previously excised. 相似文献
42.
Nurse-midwifery students face multiple stressors in their educational experience. Strategies to resolve stress and promote adaptation to the new role are examined and measures used to promote students' adaptation to the educational experience are described. 相似文献
43.
A family including three children with DiGeorge syndrome is described. One child died in the neonatal period from cardiac anomalies accompanying complete DiGeorge syndrome. The two surviving siblings shared a common set of pharyngeal pouch anomalies and immunodeficiency consistent with partial DiGeorge syndrome, and other morphologic anomalies characteristic of the velocardiofacial syndrome with which familial DiGeorge syndrome is associated (reviewed in reference 1). Both had normal karyotypes. Both presented with recurrent otitis media and sinopulmonary infections, CD4+ T cell lymphopenia, and defective DCH skin test responses to recall T cell antigens. Both had low serum IgM levels and IgG4 levels at the lower limits of normal. Immunization with bacterial polysaccharides resulted in impaired IgG antibody responses to the same set of antigens (H. influenzae polyribophosphate and S. pneumoniae capsular serotypes 9N and 14), while responses to protein antigens were intact. Both siblings were treated successfully with intravenous gamma globulin. The pattern of selective antibody deficiency in these patients with familial DiGeorge syndrome suggests a heritable lesion in certain regulatory antipolysaccharide CD4+ T cell subpopulations. 相似文献
44.
应用放射配体结合法证实大鼠胸腺内存在降黑素特异结合部位,该结合位点可以满足特异结合部位的基本条件:1.低结合容量;2.高亲和力;3.可饱和性;4.可逆性;5.对降黑素高度特异性。此外,该特异结合位点具昼夜节律;亚细胞分布的研究表明以细胞核含量最高,线粒体次之,并具有年龄依赖性降低,以出生时最高。 相似文献
45.
We have examined the hypothesis that people who develop contact allergies to environmental substances do so because they have heightened susceptibility. Analysis of data from 2200 consecutive patients tested with the 20 commonest antigens in a patch-test clinic showed that more people developed multiple contact allergies than would be predicted from the frequency of single allergies; the excess was too great to be explained by chance and increased with number and rarity of the combinations of sensitizers. The possibility that this was due to enhanced individual susceptibility to sensitization rather than concomitant exposure to several sensitizers was confirmed by showing that patients with multiple allergies are more readily sensitized experimentally, and to a greater degree than normal, by dinitrochlorobenzene (DNCB), an unrelated antigen. The defect involves induction rather than expression of sensitivity. Amplification of the response to DNCB is proportional to susceptibility (calculated from the ratio of observed prevalence of multiple allergies to that predicted from the prevalence of single allergies) throughout the range from normal subjects, through those with a single sensitivity, to those with rare, multiple allergies. Therefore, we conclude that individual susceptibility is an important factor in the development of contact dermatitis, and occurs by a non-antigen-specific amplification of immune sensitization. 相似文献
46.
A manual bead assay for the determination of absolute CD4+ and CD8+ lymphocyte counts in human immunodeficiency virus-infected individuals. 下载免费PDF全文
CD4+ T lymphocytes are currently the most common surrogate marker indicating disease progression in individuals infected with human immunodeficiency virus (HIV). Since the cost of enumerating lymphocyte phenotypes is quite high, an inexpensive bead assay analyzed by light microscopy (cytosphere assay; Coulter Corporation, Hialeah, Fla.) was developed as an alternative method for counting CD4+ and CD8+ T lymphocytes. To evaluate the reliability of the cytosphere assay, heparinized blood was collected from 117 HIV-infected individuals and tested for both CD4+ and CD8+ lymphocytes by flow cytometry and the cytosphere assay. The Pearson correlation coefficient of the cytosphere assay compared with that of flow cytometry for CD4+ T lymphocytes was 0.93, with mean values +/- standard deviations of 534 +/- 509 by flow cytometry and 499 +/- 477 by the cytosphere assay. The correlation coefficient for CD8+ T lymphocytes was 0.86, with mean values of 831 +/- 543 by flow cytometry and 746 +/- 472 by the cytosphere assay. The sensitivity and specificity of the cytosphere assay in determining absolute CD4+ T-lymphocyte counts of less than 200/microliters were 97.6 and 94.7%, respectively. The positive predictive value was 90.9%, and the negative predictive value was 98.6%. The cytosphere assay was highly correlative to flow cytometry in determining CD4+ and CD8+ T-lymphocyte counts among HIV-infected patients. The ease and limited resources needed to perform this test make it ideal in developing countries and other areas where technology and finances are limited. 相似文献
47.
Phenotypic characteristics, fatty acid composition, and isoprenoid quinone content of CDC group IIg bacteria. 下载免费PDF全文
Eleven strains of eugonic, nonoxidative, gram-negative rods isolated from clinical specimens formed a distinct group that was designated CDC group IIg. Five of the 11 isolates were from wounds. The phenotypic characteristics of CDC group IIg were most similar to those of Weeksella species, with the major difference being that CDC group IIg strains grew on MacConkey agar in 1 to 2 days, did not hydrolyze gelatin, and did not produce urease. All 11 strains of CDC group IIg possessed a distinct fatty acid profile that was characterized by large amounts (19 to 29%) of 18:1 omega 7c, 16:0, and 16:1 omega 7c, moderate amounts (6 to 10%) of 3-OH-14:0 and 14:0, and smaller amounts (1 to 2%) of 18:2, 18:0, and 3-OH-16:0. This fatty acid profile differs from those of Weeksella species by the absence of branched-chain fatty acids. CDC group IIg contains ubiquinone-8, as opposed to menaquinone-6 in Weeksella species. The isolates were susceptible to a variety of antimicrobial agents, including the aminoglycosides, tetracyclines, quinolones, sulfonamides, and polymyxin B. 相似文献
48.
S. Shousha A. Schoenfeld Jill Moss I. Shore H. D. Sinnett 《Ultrastructural pathology》1994,18(5):519-523
Although recent epidemiologic studies suggest that silicone augmentation of the breast is not associated with an increased risk of mammary carcinoma, cases of breast carcinoma arising in augmented breasts are being increasingly encountered as a large number of patients who had augmentation are getting older. A case of a 51-year-old woman with a 20-year history of breast augmentation who developed an invasive cribriform carcinoma associated with extensive microcalcification is presented. The patient had submammary silicone implants 20 years ago that were replaced, because of local complications, in subpectoral positions 10 years later. Dispersive X-ray microanalysis failed to demonstrate silicone in sections of the tumor and adjacent breast tissue. Appropriately fixed tumor tissue was available for electron microscopic examination. The tumor cells were rich in mitochondria, and their luminal surfaces were endowed with abundant microvilli, but the cell surfaces that came closest to the calcified microspheriols were devoid of microvilli and had cellular buddings between the microspheriols. It is suggested that the tumor cells might have been actively involved in the process of microcalcification. 相似文献
49.
Lysosomal enzyme activities were studied in cells derived from the following types of leukaemia: chronic myeloid, acute myeloid, acute myelomonocytic, acute monocytic, non-T, non-B cell acute lymphoblastic, T-cell acute lymphoblastic, B-cell chronic lymphocytic and T-cell chronic lymphocytic. Activities of beta-hexosaminidase and alpha-mannosidase were significantly higher in cells from acute monocytic and acute myelomonocytic leukaemias, and somewhat higher in the other myeloid leukaemias, when compared with control granulocytes. Activities of beta-hexosaminidase, alpha-mannosidase, alpha-fucosidase, beta-glucuronidase and acid phosphatase were markedly lower in B cells of chronic lymphocytic leukaemia when compared with control or other leukaemic lymphoid cells. On isoelectric focusing abnormal patterns of beta-hexosaminidase, alpha-mannosidase and beta-glucuronidase activities were commonly found in myeloid and non-T, non-B cell leukaemias. All patients with acute myeloid leukaemia exhibited a relative decrease in the B form of beta-hexosaminidase activity. The results described show that studies on lysosomal enzymes may assist in the classification of different types of leukaemia. 相似文献
50.