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991.
This report details the fine-needle aspiration biopsy (FNAB) cytomorphologic features of two cases of salivary gland mycosis. Both patients had acquired immunodeficiency syndrome (AIDS) and presented with parotid gland masses. The first patient had Histoplasmosis with secondary infection by Candida. Cytopathologically, the FNAB smears showed classic features of a deep-seated mycosis characterized by necrosis and scattered fungal forms. The second patient had a colonizing sialadenitis caused by either Asperigillus or Fusarium. Cytopathologically, the findings were similar to those seen in aspergillomas of the lung orparanasal sinuses with numerous hyphal forms and an absence of an inflammatory response. Because mycotic disease can induce a wide spectrum of pathogenic change, other benign or malignant, solid or cystic lesions enter into the differential diagnosis. Diagn Cytopathol 1994; 11:286–290. © 1994 Wiley-Liss, Inc. 相似文献
992.
从兔网织红细胞提纯的红细胞分化调节因子(erythroid differentiation factor,EDF),能对体外培养的自发转化成纤维细胞系L929及人鼻咽癌细胞系KB产生作用。当EDF剂量为0.10μg/ml时,可引起L929细胞形态发生改变,并有细胞核固缩现象。第2d的细胞生长抑制率为64.86%,软琼脂集落形成率为0;第5d时细胞增殖为负值。~3H-TdR掺入率明显降低。EDF剂量为0.15μg/ml时,对KB细胞生长已有抑制作用。EDF剂量达0.30μg/ml时,生长抑制明显。以上结果证明了EDF对恶性细胞具有增殖抑制作用。这种作用对不同种类细胞敏感性不同,并且与剂量呈正相关。 相似文献
993.
Mutations in the human fibrillin 1 gene (FBN1) cause the Marfan syndrome (MFS), an autosomal dominant connective tissue disorder. Knowledge about FBN1 mutations is important for early diagnosis, management, and genetic counseling. However, mutation detection in FBN1 is a challenge because the gene is very large in size ( approximately 200 kb) and the approximately 350 mutations detected so far are scattered over 65 exons. Conventional methods for large-scale detection of mutations are expensive, technically demanding, or time consuming. Recently, a high-capacity low-cost mutation detection method was introduced based on denaturing high-performance liquid chromatography (DHPLC). To assess the sensitivity and specificity of this method, we blindly screened 64 DNA samples of known FBN1 genotype exon-by-exon using exon-specific DHPLC conditions. Analysis of 682 PCR amplicons correctly identified 62 out of 64 known sequence variants. In three MFS patients of unknown FBN1 genotype, we detected two mutations and eight polymorphisms. Overall, 20 mutations and two polymorphisms are described here for the first time. Our results demonstrate 1) that DHPLC is a highly sensitive (89-99%, P = 0.05) method for FBN1 mutation detection; but 2) that chromatograms with moderate and weak pattern abnormalities also show false positive signals (in all 45-59%, P = 0.05); 3) that the difference in the chromatograms of heterozygous and homozygous amplicons is mostly independent of the type of sequence change; and 4) that DHPLC column conditions, additional base changes, and the amounts of injected PCR products influence significantly the shape of chromatograms. A strategy for FBN1 mutation screening is discussed. 相似文献
994.
995.
Antonín Bukovský Michael R. Caudle Jeffrey A. Keenan Jay Wimalasena Nirmala B. Upadhyaya Stuart E. Van Meter 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,36(6):327-341
PROBLEM: We have recently observed that the regression of corpora lutea (CL) in women during the reproductive period of life is accompanied by a diminution of Thy-1 differentiation protein release from vascular pericytes and an accumulation of T lymphocytes and activated macrophages among both degenerating granulosa lutein cells (GLC) and theca lutein cells. These data suggest that the immune system and other stromal factors, representing components of the “tissue control system,” may play a role in regression of the CL. We investigated degenerating CL from climacteric women to address the possibility that the decline of immune functions with advancing age may result in incomplete regression of luteal tissue. This could contribute to the altered hormonal profiles and abnormal uterine bleeding that frequently occur during the climacteric. METHOD: Immunoperoxidase staining and image analysis were used to localize Thy-1 differentiation protein of vascular pericytes, cytokeratin staining of GLC, neural cell adhesion molecule expression by theca lutein cells, CD15 of neutrophils, CD4, CD14, CD68, and leukocyte common antigens of macrophages, and CD3 and CD8 determinants of T lymphocytes. We also investigated the expression of luteinizing hormone receptor (LH receptor) and mitogen activated protein kinases (MAP kinases) in luteal cells. Samples of regressing luteal tissue were obtained during the follicular phase from perimenopausal women (age 45–50) who exhibited prolonged or irregular cycles. For comparison, luteal tissues from women with regular cycles (age 29–45) and CL of pregnancy were also investigated. RESULTS: Corpora lutea of the climacteric women exhibited irregular regression of luteal tissue characterized by a lack of cytoplasmic vacuolization and nuclear pyknosis in GLC, and by a persistence of theca lutein cells exhibiting hyperplasia and adjacent theca externa layers. This was accompanied by a continuing release of Thy-1 differentiation protein from vascular pericytes. Persisting GLC lacked surface expression of macrophage markers (CD4, CD14, CD68 and leukocyte common antigen) as well as nuclear granules exhibiting CD15 of neutrophils, detected in regularly regressing GLC. In addition, such persisting GLC showed weak or no LH receptor expression, and retained the expression of cytokeratin. They also exhibited enhanced staining for MAP kinases. Strong cytoplasmic MAP kinase expression with occasional nuclear translocation was also detected in persisting theca lutein cells, indicating high metabolic activity of these cells. T lymphocytes, although occasionally present in luteal stroma within luteal convolutions, did not invade among persisting GLC and were virtually absent from layers of theca externa and theca lutein cells. CONCLUSIONS: These data indicate that the regressing CL in climacteric women may exhibit persistence of luteal cells, perhaps because of age-induced alterations of the immune system and other local stromal homeostatic mechanisms involved in the elimination of luteal cells. Persisting GLC and/or theca lutein cells may exhibit abnormal hormonal secretion that contributes to the alteration of target tissues, such as the endometrium, resulting in abnormal uterine bleeding, hyperplasia, and neoplasia. 相似文献
996.
997.
Zuochen Du Anwei Chen Lu Huang Xin Dai Qiuyue Chen Di Yang Liling Li Heather Miller Lisa Westerberg Yuan Ding Xuemei Tang Masato Kubo Liping Jiang Xiaodong Zhao Hua Wang Chaohong Liu 《The Journal of allergy and clinical immunology》2021,147(5):1907-1923.e6
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998.
George Capone Mary Stephens Stephanie Santoro Brian Chicoine Peter Bulova Moya Peterson Joan Jasien Anna Jo Smith Down Syndrome Medical Interest Group Adult Health Workgroup 《American journal of medical genetics. Part A》2020,182(7):1832-1845
Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed. 相似文献
999.
目的 考察一个548位点C→T单核苷酸突变的雌激素受体(ER)在体外条件下,对乳腺癌细胞株(MCF-7)信号通路的影响,以探讨ER单核苷酸突变引起非雌激素依赖性性早熟的可能机制.方法 用重叠延伸PCR定点诱变技术对548位点的碱基进行定点突变.构建定点突变表达载体pSG5-MuER.构建含雌激素受体反应元件(ERE)的萤光素酶报告基因载体pGL3-ERE-Luc.将野生和突变ER质粒分别和pGL3-ERE-Luc共转染MCF-7细胞,观察萤光素酶的变化,以检测突变ER反应活性的变化.结果 成功构建ER突变质粒psG5-MuER和ER报告质粒pGL3-ERE-Luc,psG5-MuER较pSG5-ER能够增加萤光素酶的产生.结论 该突变雌激素受体在体外具有高促转录活性特征,构建的载体可用于进行进一步的相关研究. 相似文献
1000.
Takeki Tsutsui Yuriko Tanaka Yuko Matsudo J. Carl Barrett 《Methods in Cell Science》1995,17(2):155-160
Immortalization of normal human fibroblasts is a very rare event. Multiple genes such as p53 and cellular senescence genes are possibly involved in immortalization of human fibroblasts, suggesting that multiple treatments with carcinogens are required for the immortalization. We describe here the procedure for immortalization of human fibroblasts (MDAH 087) from Li-Fraumeni cancer syndrome with a germ-line p53 mutation. The cells were subjected to multiple treatments with aflatoxin B1 (AFB1) in the presence of exogenous metabolic activation with rat liver post-mitochondrial supernatant (PMS), and 3 of 9 MDAH 087 cell cultures treated 1–3 times with 0.1–1 µg/ml AFB1 became immortal, defined as continuous growth for over 300 population doublings after the first treatment. However, cultures of human fibroblasts from a normal embryo treated under the same conditions failed to escape senescence. The results indicate that the model of human fibroblasts with a mutated p53 allele exposed to AFB1 is potentially useful for studying mechanisms of chemically induced immortalization. 相似文献