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51.
BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) is characterized by a heightened Th2 CD4+ T-cell response to Aspergillus fumigatus (Af) allergens and a hyper-immunoglobulin E (IgE) state compared with cystic fibrosis patients without ABPA. The IgE serologic differentiation of ABPA from atopic CF patients can be difficult. We propose as the reactivity with purified antigens varies qualitatively and quantitatively and that the antibody response is more specific than with crude Af antigen extract, the IgE responses to purified recombinant Af allergens may differentiate ABPA from atopic CF patients. METHODS: Serum IgE reactivity to seven recombinant purified allergens and to a crude extract of Af was measured in 15 ABPA, in 23 Af skin test positive (ST+), and in 19 Af skin test negative (ST-) CF patients. Four of the ABPA CF patients were studied before and after developing ABPA. Nine ABPA patients were studied during flares and remissions of ABPA. RESULTS: Allergic bronchopulmonary aspergillosis patients had significantly increased IgE reactivity to Asp f2, f3, f4, f6, and f16 compared with the Af ST+ and ST- non-ABPA CF patients. In the ABPA patients studied before and after developing ABPA, IgE reactivity also increased to Asp f2, f3, f4, and f6, and to the crude extract. In ABPA CF patients, IgE reactivity to Asp f1, f2, f3, and f6 significantly increased during periods of ABPA flares compared with periods of remission. Analysis of the receiver operating curve demonstrated that IgE reactivity to Asp f3 and f4 gave the best sensitivity and specificity and were better than IgE reactivity to a crude extract of Aspergillus. Furthermore, in ABPA patients studied during periods of remission the IgE reactivity to Asp f3 and f4 remained significantly elevated compared with Af ST+ non-ABPA patients. The IgE responses when considered either to be positive or negative to Asp f3 and f4 significantly differentiated ABPA from Af ST+ and ST- non-ABPA CF patients. In contrast, IgE reactivity was considered positive to the crude extract in 89% of ABPA, 61% of Af ST+, and 0% of Af ST- non-ABPA CF patients. CONCLUSIONS: Immunoglobulin E reactivity to a panel of purified Af allergens, especially to Asp f3 and f4, differentiates ABPA from atopic Af ST+ non-ABPA CF patients. Serial determinations of IgE reactivity to individual purified Aspergillus antigens, especially Asp f3, demonstrates that increases in IgE reactivity may provide improved distinction between stages of flares and remission compared with changes in IgE reactivity to a crude Aspergillus extract.  相似文献   
52.
A total of 392 men referred for intracytoplasmic sperm injection (ICSI) participated in genetic analysis. The control group consisted of 100 normal fertile males. Chromosome and DNA analyses were performed to investigate the frequency of Y-chromosome microdeletions and CFTR mutations (the controls underwent DNA analysis only). An abnormal karyotype was found in 4.6% of all males, but the frequency among men with azoospermia was higher, at 11.7%. Y-chromosome microdeletions were found only among men with azoospermia (6.5%) and men with extreme oligospermia (2%). Compound heterozygosity for CFTR mutations was found in men with azoospermia (3.9%) and congenital bilateral absence of vas deferens (CBAVD) only. We conclude that all couples referred for ICSI should be offered chromosome analysis. DNA analysis for Y-chromosome microdeletions should be reserved for men with azoospermia or extreme oligospermia (<1 x 106 spermatozoa). Analysis for CFTR mutations should be limited to those with obstructive azoospermia or those with a family history of cystic fibrosis.  相似文献   
53.
This ultrastructural study is based on nine cases of adenoid cystic carcinoma arising from the salivary glands. Electron microscopically, the tumors consisted of five cell types: relatively differentiated intercalated duct cells, secretory cells, undifferentiated cells, cells of a squamous nature, and myoepithelial cells. Special attention was paid to the characteristic extracellular substances noted by light microscopic examination of these tumors. The hyaline material of the pseudocysts contained not only mucopolysaccharide granules but also fingerprintlike structures formed by replicated basement membrane. Some of these structures had a dense core, probably composed of mucopolysaccharide granules. Cell islands surrounded by elasticlike material also were found. The true lumina were usually filled with membranovesicular structures originating from fragments of the lining cells, mainly those with squamous differentiation. These membranovesicular structures included electron-dense rods, filamentous whorls, and structures displaying periodicity.  相似文献   
54.
55.
腮腺腺样囊性癌病人血浆P—选择素的测定   总被引:1,自引:0,他引:1  
①目的 探讨可溶性P 选择素 (sP selectin)与腮腺腺样囊性癌发展及转移的关系。②方法 用ELISA法检测 6 5例腮腺腺样囊性癌病人血浆中sP selectin的含量。③结果 腮腺腺样囊性癌病人血浆中sP se lectin的含量均明显高于正常对照组 (t=- 12 .6 5 ,P <0 .0 1) ;而且血浆中sP selectin的水平与病情发展有关 (F =92 .6 7,q =5 .6 0 2~ 13.45 3,P <0 .0 1)。 ④结论 sP selectin检测有可能成为腮腺腺样囊性癌病人辅助诊断、观察病情发展的一项有价值的指标。  相似文献   
56.
唐峰  王虹  赵为之  李薇  李琼  庄丽 《复旦学报(医学版)》2001,28(2):121-123,F003
目的研究涎腺腺样囊性癌MMP-2和MMP-9表达情况,评估其与涎腺腺样囊性癌神经浸润和淋巴 结转移的关系。方法选取53例涎腺腺样囊性癌,以抗MMP-2和MMP-9单克隆抗体用Envision法进行免疫 组织化学染色和半定量分析。结果MMP-2和MMP-9在涎腺腺样囊性癌中的表达率分别为67.92%和 79.25%;有神经浸润的腺样囊性癌其MMP-2和MMP-9的表达水平远高于无浸润者(P<0.05,P<0.05);随 着MMP-2和MMP-9的表达水平增高,淋巴结转移率也增高(P<0.05,P<0.05)。结论提示MMP-2和 MMP-9的高表达与涎腺腺样囊性癌易侵犯神经的特性及发生淋巴结转移密切相关。  相似文献   
57.
目的 探讨单纯性肾囊肿的组织起源。方法 20例囊液标本取自12位男性和8位女性,采用两种方法:(1)测定囊液中钠(Na^ )、钾(K^ )、氯(Cl^-)、尿素氮(BUN)、肌酐(Cr)、葡萄糖(Glu)、总蛋白(TP)等物质的浓度,并与血浆中的浓度相比较;(2)选用两种高选择定位于不同肾小管节段的酶标植物血凝素,四叶莲凝集素和jacalin凝集素,对单纯性肾囊肿标本进行组织化学研究。四叶莲凝集素定位于近端肾小管,而jacalin凝集素定位于远端肾小管和集合管。结果 (1)标本中Na^ 、K^ 、Cl^-、BUN、Cr、Glu的浓度与血浆中浓度基本相等,而血浆中总蛋白的浓度则高于囊液中浓度;(2)15例囊肿内衬上皮的四叶莲凝集素染色均呈强阳性,而jacalin凝集素染色有7例为阴性,另8例为部分弱阳性。结论 单纯性肾囊肿可能起源于近端肾小管。  相似文献   
58.
Pancreatic solid pseudopapillary neoplasm (SPN) is a rare low grade malignant tumour. Distinguishing this entity from other pancreatic neoplasms is critical for therapeutic decision making and prognostication. It predominantly affects young female patients <40 years of age, with excellent clinical outcome following surgical removal. The gold standard diagnostic test is cytopathological or histopathological assessment of fine needle aspirate. There are two main difficulties with this. First, SPN can present with morphological and immunohistochemical appearances that can closely mimic other pancreatic tumours, in particular, pancreatic neuroendocrine tumour (NET). Second, the amount of diagnostic material from fine needle aspiration can be limited. Here, we present a cytopathological case with both challenges during the pre-operative investigation of SPN. The case exemplifies the importance of combining morphological features with a targeted panel of immunohistochemistry to arrive at the diagnosis.  相似文献   
59.
Multifocal cystic oncocytosis (MCO) is a rare, benign process accounting for approximately 0.1% of salivary gland lesions. Salivary oncocytosis is characterized by multiple unencapsulated solid nodules of oncocytic cells derived from transformed striated ducts. MCO is a variant of salivary oncocytosis which manifests as cystically dilated striated ducts. It is difficult to obtain a definitive preoperative diagnosis of MCO; therefore, these lesions are commonly treated with surgery. We report the unique case of a 66-year-old male who previously underwent a superficial left parotidectomy for a pleomorphic adenoma. Four years later, he presented with clinical and radiographic suspicion of a multifocal recurrent pleomorphic adenoma. The patient subsequently underwent a revision parotidectomy. However, final pathology confirmed a diagnosis of MCO. Although MCO is commonly treated with surgery due to lack of a definitive preoperative diagnosis, surgery is unnecessary outside of diagnostic, functional or cosmetic considerations. Thus, if a patient with parotid oncocytosis treated by superficial parotidectomy develops disease re-manifestation in the residual deep lobe, further surgery is not indicated. There is no risk of malignant progression in this process. We report on this unusual entity as it may mimic salivary malignancy or, as in this case, recurrence of benign disease.  相似文献   
60.
Retrorectal or presacral tumors are rare lesions located in the presacral area and considered as being derived from multiple embryological remnants. These tumors are classified as congenital, neurogenic, osseous, inflammatory, or miscellaneous. The most common among these are congenital benign lesions that present with non-specific symptoms, such as lower back pain and change in bowel habit. Although congenital and developmental tumors occur in younger patients, the median age of presentation is reported to be 45 years. Magnetic resonance imaging plays a crucial role in treatment management through accurate diagnosis of the lesion, the evaluation of invasion to adjacent structures, and the decision of appropriate surgical approach. The usefulness of preoperative biopsy is still debated; currently, it is only indicated for solid or heterogeneous tumors if it will alter the treatment management. Surgical resection with clear margins is considered the optimal treatment; described approaches are transabdominal, perineal, combined abdominoperineal, and minimally invasive. Benign retrorectal tumors have favorable long-term outcomes with a low incidence of recurrence, whereas malignant tumors have a potential for distant organ metastasis in addition to local recurrence.  相似文献   
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