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排序方式: 共有4245条查询结果,搜索用时 15 毫秒
1.
Shuichi Kuniyuki 《The Journal of dermatology》1997,24(2):120-124
A 50-year-old Japanese man had a blue-black patch on the dorsum of his right wrist. Light and electron microscopic study of the lesion revealed dermal melanocytes containing mature melanosomes, predominantly in the upper dermis. This case was diagnosed as acquired dermal melanocytosis confined to the right wrist. 相似文献
2.
Borras Merce; Valdivielso Jose M.; Egido Ramon; Vicente de Vera Pilar; Bordalba Josep Ramon; Fernandez Elvira 《Nephrology, dialysis, transplantation》2006,21(3):789-791
3.
Daniel B. Costa Christopher A. Fisher Kenneth B. Miller German A. Pihan David P. Steensma Richard J. Gibbons Douglas R. Higgs 《European journal of haematology》2006,76(5):432-435
Abstract: We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function. 相似文献
4.
Nuthapong Ukarapol Nirush Lertprasertsuk George J. Fuchs Lumduan Wongsawasdi Virat Sirisanthana 《Digestive endoscopy》2004,16(1):26-29
Objective: To evaluate the role of gastrointestinal (GI) endoscopy in human immunodeficiency virus (HIV)‐infected children with GI problems. Methods: From 1998 to 2002, we retrospectively reviewed all cases of HIV‐infected children presenting with GI problems in which an upper or lower GI endoscopy was indicated. The initial diagnostic endoscopic examination and any repeat endoscopic session leading to a new diagnosis were used in the data analysis. Tissue biopsies were obtained from all abnormal lesions and representative sites of normal‐appearancing GI mucosa. Results: Fourteen patients (median age: 22.5 months) underwent 23 sessions of GI endoscopy, including 10 esophagogastroduodenoscopy, nine colonoscopy and four flexible sigmoidoscopy. Chronic diarrhea was the most common indication, followed by lower GI bleeding, abdominal/retrosternal pain, dysphagia/odynophagia, and upper GI bleeding. Gross endoscopic abnormalities were observed in 78.3%; whereas histological inflammation and opportunistic pathogens were identified in 87% and 43.5%, respectively. Cytomegalovirus was the most common identified pathogen. Abnormal gross findings were significantly associated with histological inflammation and identification of pathogens (P = 0.006 and 0.046, respectively). Specific changes in medical management were made in 50% of cases as a result of endoscopic investigation. Conclusion: If non‐invasive investigations for HIV‐infected children with GI symptoms fail to establish a diagnosis, gastrointestinal endoscopy should be performed and often yields a positive result leading to changes in medical management. 相似文献
5.
目的:了解新生儿脐部感染细菌学状况,为临床提供预防及治疗参考。方法:调查我院1997年1月-2002年6月收治的有完善细菌学资料的新生儿脐炎85例,对所获得的98例致病菌的种类及药敏状况进行分析。结果:社会获得性感染主要致病菌为G^ 球菌(70.5%),金黄色葡萄球菌占比例较高。医院感染主要致病菌为C^-杆菌(51.4%),以大肠埃希菌占比例较高。两类感染所分离的细菌均具有多重耐药性,但对氨基糖苷类及喹诺酮类耐药率较低,其次是第三代头孢菌素类抗生素。结论:临床对新生儿脐部感染,特别是有严重感染中毒症状时,应首先考虑使用第三代头孢菌素类抗生素。 相似文献
6.
Core biopsies of the bone marrow are indispensable in the evaluation of fever of unknown etiology in human immunodeficiency virus-positive patients. We report two patients in whom visceral leishmaniasis was diagnosed based on the typical morphology, staining characteristics, and ultrastructure of the organisms. 相似文献
7.
John G. Guccion Debra A. Benator Jack Zeller Basel Termanini Nirmal Saini 《Ultrastructural pathology》1995,19(1):15-22
Two cases of intestinal spirochetosis (IS) with acquired immunodeficiency syndrome are reported. In case 1, a 48-year-old homosexual black man presented with a 1-month history of alternating watery diarrhea and constipation, which dissipated following the removal of two colonic hyperplastic polyps containing IS. In case 2, a 26-year-old homosexual black man presented with a 3-month history of persistent bloody diarrhea and was found to have chronic shigellosis and IS. Pathologic findings of IS were similar in both cases. Basophilic fringes typical of IS covered the surfacing colonic epithelium and consisted of dense growths of spirochetes adherent to and oriented perpendicular to the plasma membranes of the surfacing epithelium. The spirochetes measured 3 to 5 μm in length and 0.2 (im in width, contained four to eight axial fibrils, and closely resembled Brachyspira aalborgi ultrastructurally. These cases are notable because the histopathologic changes of IS were more extensive than generally described. There was involvement of both the right colon and rectum by IS in case 2, and in both cases there was extension of the IS down into the crypts of Lieberkiihn, spirochetal invasion of the colonic mucosa, and a conspicuous inflammatory response by macrophages in the underlying lamina propria. 相似文献
8.
Steffanie Sabbaj Michael F. Para Robert J. Fass Patrick W. Adams Charles G. Orosz Caroline C. Whitacre 《Journal of clinical immunology》1992,12(3):216-224
The lymphocyte proliferative response to recall antigens is lost following HIV infection. We sought to devise a means by which the functional immune status of persons in the early stages of HIV infection could be monitored quantitatively. The response to tetanus toxoid was examined in 45 HIV-infected individuals and 11 controls using conventional lymphocyte proliferative assays concurrently with limiting dilution analysis utilizing the secretion of interleukin-2 as the measure of a response. Our data show that the limiting dilution analysis detects tetanus toxoid-reactive T cells in 80% of those tested, as compared to only 44% by proliferation. However, the frequency of tetanus-reactive T cells in HIV-infected individuals (median frequency = 1/59,156) is decrease five-fold as compared to seronegative controls (median frequency = 1/11,599). Longitudinal studies demonstrated a time-dependent decrease in the frequency of tetanus-specific T cell responses in the HIV-infected individuals. Thus, the limiting dilution analysis is a quantitative approach for detecting antigen-specific T cells in HIV-infected individuals, and may be used to monitor changes in T cell function in HIV infection. 相似文献
9.
获得性免疫缺陷综合征(AIDS)合并播散性弓形虫病尸检的病理学研究 总被引:3,自引:0,他引:3
报道美国纽约地区9例播散性弓形虫病尸检材料,均有脑部病变,8例累及心脏,4例累及肺脏,尚见胰腺、消化道、甲状腺、淋巴结、泌尿生殖器官等受累。其中弓形虫性脑炎9例,心肌炎4例,肺炎3例,胰腺炎2例。仅脑炎、肺炎产牛症状,经脑CT扫描、弓形虫抗体测定提示本病,并经涂片、骨髓活检和尸检证实,以查见弓形虫为依据。临床以神经精神症状和肺部感染症状为主。病变分为静止(潜伏)、组织坏死、炎症反应及增生修复四种状态,强调囊型弓形虫形态学识别的诊断意义。 相似文献
10.