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51.
关于乳腺普通性增生、不典型增生和原位癌相互关系及鉴别诊断的探讨 总被引:11,自引:1,他引:11
目的 探讨各种类型乳腺增生症的发病特点、形态学分类、不典型增生与乳腺癌的关系以及不典型增生与乳腺原位癌的鉴别诊断标准。方法 (1)观察本院300例乳腺良性增生性病变的临床发病特点及其病理形态改变。(2)观察86例大切片乳腺癌旁不典型增生病灶与癌灶的关系。结果 乳腺增生症中,纤维腺瘤为主型好发于21~30岁年龄组,而不典型增生病变则多见于40~60岁组。其中囊肿病仅占6.0%,而纤维腺瘤变达25.4%;癌旁组织中不典型增生发生率为65.1%,其中以导管原位癌发生率最高,达74.9%。结论 研究证实了1997年(舟山)“乳腺增生症的组织学分类”(推荐方案)的可行性。乳腺不典型增生与乳腺癌的发生密切相关。乳腺增生症可归纳为普通性增生和不典型增生。不典型增生的特殊增生细胞具有特别的诊断价值。重度不典型增生与原位癌的鉴别诊断有一定困难,但大部分可分。 相似文献
52.
Jiang X Gao X Zheng H Yan M Liang W Shao Z Li W Zhang E Hu Y Hai R Yu D Kan B Xu J 《Clinical and diagnostic laboratory immunology》2004,11(6):1182-1184
Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested. 相似文献
53.
Molecular epidemiology of Vibrio cholerae O139 in China: polymorphism of ribotypes and CTX elements 总被引:5,自引:0,他引:5
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Qu M Xu J Ding Y Wang R Liu P Kan B Qi G Liu Y Gao S 《Journal of clinical microbiology》2003,41(6):2306-2310
Vibrio cholerae O139, the second etiological serogroup of cholera, triggered the first outbreak of O139 cholera in China in 1993. To analyze the clone polymorphism of O139 isolates in China, 117 strains of V. cholerae O139, isolated from different areas in China between 1993 and 1999, were selected to characterize the phylogenetic relationships by molecular techniques. Analysis of restriction fragment length polymorphism in the conserved 16S rRNA gene revealed seven different ribotypes within the 117 strains. Among these strains, there were eight that lacked the cholera toxin gene (ctxAB), zot, and the repetitive sequence (RS); these eight strains belonged to three individual ribotypes. Our results suggested that V. cholerae O139 strains in China had clone diversity in phylogeny. The results of our hybridization patterns for CTX genetic elements (ctxAB, zot, and RS) showed that CTXPhi genomes in most V. cholerae O139 strains had two or more copies and had extensive restriction patterns even for the strains which belong to the same ribotype. For 22 (20.1%) strains, the copies of ctxAB were different from those of zot, suggesting that a ctxAB-negative CTXPhi genome may exist in O139 strains. This ctxAB-negative CTXPhi genome may coexist with the intact CTXPhi genome in a strain. In addition, the dendrogram for I-CeuI-generated pulsed-field gel electrophoresis patterns showed that V. cholerae serogroup O139 has a closer relationship with one strain of serogroup O22 than with the strains of serogroup O1. The results of this study showed the clonal diversity and the distribution of O139 strains in China, suggesting multiple origins of the O139 cholera epidemic or sporadic events. 相似文献
54.
The present study reports the detection of antibodies to β2 microglobulin in the sera of patients with systemic lupus erythematosus (SLE). Using a Farr-type ammonium sulphate precipitation assay, test sera were reacted with 125Iβ2 microglobulin, and immunoglobulins precipitated by 50% saturated ammonium sulphate. Increased β2 microglobulin binding activity (normal values: mean±2 sd = 35.5 ±7.8) was detected in 18 of 42 SLE sera. Anti-HLA sera did not reveal increased binding activity, suggesting that the antibody in SLE serum was directed toward free β2 microglobulin. Direct validation was done by reacting 125Iβ2 microglobulin with 4 SLE sera having increased 125Iβ2 microglobulin binding activity, and subjecting the reactants to sucrose density gradient ultracentrifugation. Two peaks were obtained, one corresponding to free β2 microglobulin, and the other to 7S material complexed to β2 microglobulin. Normal sera demonstrated only one peak corresponding to unbound β2 microglobulin. Assays of β2 microglobulin binding activity on protein fractions obtained by Sephadex G200 column chromatography also showed the presence of increased binding activity with 7S fractions. Using a double antibody assay, the 7S material reactive to β2 microglobulin was demonstrated to be IgG. It was also shown that sera with abnormal β2 microglobulin binding activity had higher titres of antinuclear antibody compared to those lacking such activity (t = 3.18; P<0.01), indicating the pathogenetic relationship of this antibody to increased disease activity. This antibody may be responsible for some of the abnormalities of cell-mediated function previously described in SLE patients. 相似文献
55.
Keita AD Dembélé M Kané M Fongoro S Traoré M Sacko M Diallo S Sidibe S Traoré HA Doumbo O Traoré I 《Bulletin de la Societe de pathologie exotique (1990)》2001,94(4):335-338
Urinary bilharziasis is a parasitic infection responsible for vesical, urethral and renal lesions. The authors demonstrate the importance of ambulatory echography on a large scale and describe various echographic lesions. Vesical attacks occurred in 27% of the wall irregularity, 44% of the masses and polyps. Pyelic and urethral abnormalities occurred in 16.6% and 29.9% of cases respectively at the baseline in 1991. These prevalence rates decreased after seven years, in 1998. The authors discuss the utility of chemotherapy with praziquantel and the necessity of a periodical mass treatment in the areas with high bilharziasis endemicity in Mali. 相似文献
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59.
Wong N Hui AB Fan B Lo KW Pang E Leung SF Huang DP Johnson PJ 《Cancer Genetics and Cytogenetics》2003,140(2):124-132
Nasopharyngeal carcinoma (NPC) cell lines and xenografts represent valuable models for functional and therapeutic studies on this common malignancy in Southeast Asia. The karyotypic information in most NPC cell lines and xenografts, however, remains largely unclear to date. We have characterized the chromosomal aberrations in six commonly used human NPC cell lines and xenografts using the molecular cytogenetic technique of comparative genomic hybridization (CGH). Genomic imbalances identified in cell lines were further correlated with structural abnormalities indicated from spectral karyotyping (SKY) analysis. CGH revealed consistent overrepresentations of 8q (six out of six cases) with a smallest overlapping region identified on 8q21.1q22. Other common gains included 7p (4/6 cases), 7q (4/6 cases), 12q (4/6), and 20q (4/6 cases), where minimal overlapping regions were suggested on 7p15p14, 7q11.2q21, and 12q22q24.1. Common losses were detected on 3p12p21 (4/6 cases) and 11q14qter (4/6 cases). Although SKY analysis on cell lines revealed predominantly unbalanced rearrangements, reciprocal translocations that involved chromosome 2 [i.e., t(1;2), t(2;3), and t(2;4)] were suggested. Furthermore, SKY examination illustrated additional breakpoints on a number of apparently balanced chromosomes. These breakpoints included 3p21, 3q26, 5q31, 6p21.1p25, 7p14p22, and 8q22. Our finding of regional gains and losses and breakpoints represents information that may contribute to NPC studies in vitro. 相似文献
60.
Radiation proctitis is a frequent acute complication encountered with pelvic irradiation. This study was aimed at establishing the optimal radiation dose for radiation-induced proctitis in rats. Female Wistar rats were used. The rectal specimens were examined morphologically at 5th and 10th day following 10-30 Gy irradiation in single fraction. With increasing dose, mucosal damage became worse, and there was a prominent reaction after > or =15 Gy. We selected 17.5 Gy as an optimal dose for radiation proctitis and examined specimens at day 1-14 and at week 4, 6, 8, and 12 after 17.5 Gy. The rectal mucosa revealed characteristic histological changes with time. An edema in lamina propria started as early as 1-2 days after irradiation and progressed into acute inflammation. On day 7 and 8, regeneration was observed with or without ulcer. Four weeks later, all regeneration processes have been completed with end result of either fibrosis or normal appearing mucosa. This study showed that the radiation injury of the rectum in rat develops in dose-dependent manner as it has reported in previous studies and suggested that 17.5 Gy in single fraction is the optimum dose to evaluate the protective effect of various medications for radiation proctitis in face of the clinical situation. 相似文献