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1.
K Mahmood M N Chowdhury E A Ayoola I A Mofleh R S Rashed F Z Faleh 《Tropical gastroenterology》1991,12(4):188-191
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture. 相似文献
2.
Amrik Sahota Min Yang Sujuan Gao Siu L. Hui Olusegun Baiyewu Oyewusi Gureje Steven Oluwole Adesola Ogunniyi Kathleen S. Hall Hugh C. Hendrie 《Annals of neurology》1997,42(4):659-661
As a part of our ongoing study on Alzheimer's disease (AD) in elderly African Americans, we obtained clinical assessment and apolipoprotein E (ApoE) genotype data on 288 individuals (including 60 with AD). The ApoE σ4 allele frequency was significantly increased in AD patients compared with controls. The age-adjusted odds ratio (OR) for AD in σ4 homozygotes was 4.83 (95% confidence interval [CI], 1.71–13.64) compared with the σ3/σ3 genotype, but the OR for AD with the σ3/σ4 genotype did not reach significance (1.20; 95% CI, 0.58–2.45). These findings suggest that the association between ApoE σ4 and AD is weaker in African Americans than in whites. 相似文献
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Fadare O Hileeto D Gruddin YL Mariappan MR 《Archives of pathology & laboratory medicine》2004,128(9):1046-1049
Although mucoepidermoid carcinoma is the most common primary malignancy of the salivary glands, the sclerosing morphologic variant of this tumor is extremely rare, with only 6 reported cases. As its name suggests, sclerosing mucoepidermoid carcinoma is characterized by an intense central sclerosis that occupies the entirety of an otherwise typical tumor, frequently with an inflammatory infiltrate of plasma cells, eosinophils, and/or lymphocytes at its peripheral regions. The sclerosis associated with these tumors may obscure their typical morphologic features and result in diagnostic difficulties. Tumor infarction and extravasation of mucin eventuating in reactive fibrosis are 2 mechanisms of formation that have been suggested as underlying this morphologic variant. We describe herein another case of sclerosing mucoepidermoid carcinoma that was diagnosed in a 44-year-old woman and review the relevant literature. Morphologic evidence in support of the mucin extravasation hypothesis was identified, as small pools of mucin were present throughout the tumor. However, there was no concentration of the mucin pools near the areas with the most viable tumor cells, which would have provided evidence for a temporal sequence that eventuates in lack of mucin in the most sclerotic regions. 相似文献
6.
Mariappan MR Zehnder J Arber DA Lay M Fadare O Schrijver I 《International journal of surgical pathology》2005,13(3):253-258
Specimen misidentification is a common cause of errors in surgical pathology. We report a case where bone-marrow biopsies from patients of different genders were mislabeled and molecular methods were applied to resolve the identity. A short tandem repeat (STR)-polymerase chain reaction-based assay, commonly used in paternity testing, was employed in an attempt to assign the correct identity to the specimens. However, the specimens had been processed by decalcification and the DNA yield was poor. One of the markers in the assay is the non-STR amelogenin locus that distinguishes the X and Y chromosomes. This amelogenin marker results in a product of low molecular weight, enabling unequivocal resolution of identity despite a poor DNA yield. The prevalence of errors in pathology due to specimen misidentifications is reviewed. 相似文献
7.
In North America, the most common causes of benign esophageal stricture are hiatal hernia and reflux esophagitis. These are localized to the lower end of the esophagus. 相似文献
8.
Epithelioid trophoblastic tumor: clinicopathological features with an emphasis on uterine cervical involvement. 总被引:2,自引:0,他引:2
We report on the clinical and histological features of five cases of epithelioid trophoblastic tumor, with an emphasis on its involvement of the uterine cervix. All five patients were of reproductive age (median age 38.4 years) and all, except one, presented with vaginal bleeding 3 to 18 years after the most recent pregnancy. One patient presented with amenorrhea. Elevation of serum human chorionic gonadotropin (hCG) was seen in four cases. Pathologically, the tumor involved endocervix in three cases and involved uterine corpus in another two. All five tumors were invasive, nodular lesions consisting of epithelioid intermediate trophoblastic cells that were mononuclear with abundant eosinophilic cytoplasm, along with zones of hyaline material and necrotic debris. In three cases of cervical involvement, the neoplastic cells focally replaced endocervical surface and glandular epithelium, simulating high-grade squamous intraepithelial lesions. Immunohistochemically, all five tumors displayed focal positivity for human placental lactogen and hCG. Positive nuclear staining of p63 was seen in all five cases. All patients received total hysterectomy and various regimes of adjuvant chemotherapy. Three patients survived the tumor with no recurrences or metastases with follow-up periods of 3, 7 and 16 years. One patient is currently alive with lung metastasis 1 month after the surgery. One patient died of tumor metastasis 8 months after the diagnosis. In summary, with its unusual ability to simulate an invasive squamous cell carcinoma and other epithelioid neoplasms, epithelioid trophoblastic tumor frequently poses a diagnostic challenge, especially when involving the uterine cervix. High index of suspicion and an awareness of elevation of serum chorionic gonadotropin are crucial in reaching a correct diagnosis. 相似文献
9.
The traditional association of psammoma bodies with some malignancies of the gynecologic tract raises potentially significant management difficulties when such bodies are identified on routine cervicovaginal smears. This review summarizes the reported cases of psammoma bodies identified on cervicovaginal smears in the world literature (a total of 140 cases, 113 (81%) of which had sufficient clinicopathologic information). Our conclusions are as follows: (1) The finding of psammoma bodies in this setting is distinctly unusual with an incidence of less than 0.001% on consecutively screened smears. (2) On consecutively screened smears, patients with psammoma bodies have an associated malignancy or ovarian borderline tumor 0-22.7% of the time, depending on the series; this figure climbs to 38% when all the case reports and small series in the literature are included. (3) The most reliable predictor of a malignancy in these patients is the finding of cells on the smear that by themselves are diagnostic of malignancy on cytologic grounds. (4) Other factors that, on a purely statistical basis, appear to increase the likelihood of a synchronous or metachronous malignancy or borderline tumor include an older age at diagnosis and/or clinical presentations such as postmenopausal bleeding. (5) When 1 or more psammoma bodies are identified on a cervicovaginal smear, this finding should not be ignored and should generate some clinical investigation to identify its source. 相似文献
10.
BACKGROUND: Presentation of peptides either by recipient or donor MHC molecules displayed on the surface of antigen-presenting cells is an essential element in the induction of T cell responses to transplant antigens. The finding that intrathymic (IT) injection of an immunodominant peptide induces acquired thymic tolerance suggests an indirect pathway of allorecognition in the thymus. To address this theory, we studied the effects of IT injection of host bone marrow (BM)-derived dendritic cells (DC)-pulsed with the immunodominant Wistar Furth (WF) MHC class I (RT1.Au) peptide 5 (93-109) on cardiac allograft survival in the WF-to-ACI rat combination. METHODS: DC were propagated from cultures of ACI (recipient) bone marrow (BM) maintained in a medium supplemented with granulocyte-macrophage colony-stimulating factor and IL-4. The BM-derived DC after 8 days of culture were pulsed in vitro with a single WF MHC class I peptide (Residue 93-109) with the dominant epitope, washed, and injected into the thymus of ACI rats. The ACI recipients received donor-type (WF) or 3rd party (Lewis) cardiac allografts 7 days after IT immunization with peptide-pulsed DC. RESULTS: BM-derived DC cultured in granulocyte-macrophage colony-stimulating factor and interleukin-4 for 8 days have a strong allostimulatory ability and present peptide 5 to naive syngeneic T cells in mixed lymphocyte reaction. IT inoculation of 300 microg RT1.Au peptide 5 combined with transient antilymphocyte serum immunosuppressive therapy induced donor-specific tolerance to cardiac allografts. Extension of this finding to peptide-pulsed self DC showed that IT injection of peptide 5-pulsed host DC consistently led to permanent acceptance (>150 days) of donor-type (WF) cardiac allografts, whereas third-party (Lewis) grafts were acutely rejected. The long-term unresponsive recipients challenged with second-set grafts accepted permanently (>100 days) donor-type(WF) grafts while rejecting third-party (Lewis) grafts without the rejection of the primary WF grafts. CONCLUSION: This novel finding that allopeptide-pulsed host DC induces tolerance to cardiac allografts suggests that the induction of acquired tolerance is dependent on the indirect allorecognition pathway. The results further suggest that genetically engineered DC expressing donor MHC class I or II molecules or a peptide analogue might have therapeutic potential in the induction of transplant tolerance and in the treatment of autoimmune diseases. 相似文献