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11.
Patients with ulcerative colitis (UC) are at increased risk for colorectal carcinoma (CAC). Despite the fact that patients at risk are followed closely by colonoscopy to screen for dysplasia, the prevalence of CAC is still unacceptably high. The aim of this study was to evaluate the prevalence of risk factors for CAC, such as dysplasia, and to determine the relevance of colonoscopic surveillance in the group who went on to develop cancer. A series of 24 patients with UC were diagnosed with CAC. The patients' records were analyzed retrospectively for duration of UC, prevalence of preoperative dysplasia, and other cancer risk factors (CRFs) (e.g., pancolitis, primary sclerosing cholangitis, early onset of UC, and backwash ileitis). The mean age of the patients at the time of cancer diagnosis was 43 years with an average UC duration of 15 years (6 patients had had UC less than 8 years). CAC was identified preoperatively by colonoscopy in 15 of 24 patients, with an additional 7 of 15 showing flat dysplasia. Five of nine patients without preoperatively diagnosed CAC had flat dysplasia. Overall, 19 patients had additional CRFs, most of them with at least two more CRFs. Despite a regular colonoscopic follow-up for most patients with UC, flat dysplasia was missed in 12 patients preoperatively. Therefore we suggest that patient information should also always include surgical options in each case where significant cancer risk factors are found.  相似文献   
12.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
13.
Wood  GS; Garcia  CF; Dorfman  RF; Warnke  RA 《Blood》1985,66(5):1092-1097
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.  相似文献   
14.
Vitreoretinal surgery in the treatment of neovascular glaucoma   总被引:1,自引:0,他引:1  
PURPOSE: Neovascular glaucoma develops on a background of ischemic ocular pathologies, such as diabetic eye diseases or central retinal vein occlusion. Development of neovascular membranes in the chamber angle leads to elevated intraocular pressure. Since treatment by cyclodestructive therapy or drainage surgery often fails, we have examined intense antiproliferative surgery as a treatment for advanced neovascular glaucoma. PATIENTS AND METHODS: Thirty-two patients with neovascular glaucoma subsequent to central vein occlusion or advanced diabetic retinopathy underwent antiproliferative surgery, which comprised vitrectomy, panretinal laser treatment and direct laser coagulation of the ciliary processes, followed by silicone oil tamponade. Patients were followed for a minimum of 1 year and as long as 3 years. RESULTS: After one week following surgery the intraocular pressure (IOP) was normal, ranging from 8 to 21 mm#Hg, in 52% (15/29 eyes), after 3 months the IOP was normal in 50% (16/32 eyes), after 6 months the IOP was normal in 59% (16/27 eyes) and after 1 year the IOP was normal in 72% (18/25 eyes). Of the 10 eyes that lost all sight after the surgery, 7 eyes had a history of central vein occlusion. Hypotony was observed in 6% (2/32) of the eyes 3 months following surgery; after 6 months hypotony was present in 15% (4/27) of the eyes and after 1 year hypotony was present in 12% (3/25) of the eyes. CONCLUSIONS: The theoretical premise of our surgical intervention (antiproliferative surgery) is based on the assumption that laser treatment interrupts the self enhancing pathway of retinal ischemia, release of proliferative factors and increase in intraocular pressure. The silicone oil endotamponade prevents postoperative complications and supports the rapid regression of rubeosis iridis by separating the anterior from the posterior segment.  相似文献   
15.
Geiser  CF; Bishop  Y; Jaffe  N; Furman  L; Traggis  D; Frei  E d 《Blood》1975,45(2):189-195
A toxic syndrome characterized by fever, headache, and vomiting, lasting 2-5 days, occurred in 61% of 39 children with acute leukemia in complete remission, receiving central nervous system prophylaxis with intrathecal methotrexate, and in 14% of 34 children receiving the same plus cranial radiation. The syndrome was accompanied by pleocytosis with lymphocytes, monocytoid cells, and neutrophils. There was evidence of cumulative Mtx toxicity, since the toxic syndrome occurred mostly after the third and fourth dose and did not recur with longer intervals between doses. The incidence of the syndrome was significantly reduced by the use of Elliott's B solution as Mtx diluent, rather than water or normal saline. The occurrence of pleocytosis and toxic clinical syndrome was also significantly reduced in patients receiving concomitant cranial radiation, probably due to the lympholytic action of radiotherapy and the depressed cellular response of irradiated tissues. The use of Elliott's B solution as diluent for IT Mtx and an appropriate interval between Mtx doses are suggested for prevention of this toxic syndrome.  相似文献   
16.

Background  

Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles.  相似文献   
17.
Bisphosphonates are inhibitors of osteoclastic bone resorption with therapeutic benefit in a variety of bone disorders in both adults and children. While these agents have been routinely used in adults for the past three decades, their more recent introduction into paediatric medicine means there is a paucity of data on long‐term safety and effects on dental development. There is uncertainty regarding the dental management of children treated with bisphosphonates, particularly when invasive dental procedures, such as extractions and oral surgical procedures, are required. There are limited data with which to make recommendations about the dental management of patients treated with bisphosphonates, and there are no published recommendations that specifically address paediatric patients. This paper aims to outline paediatric uses and adverse effects of bisphosphonates and present recommendations on the dental management of children receiving bisphosphonates.  相似文献   
18.
红细胞输注前的质量标准   总被引:1,自引:0,他引:1  
现行红细胞输注规则主要规定红细胞采集量和输注时存活红细胞的比例,即450ml的采集量,输注时24h平均体内的存活率至少75%。其他还限制了游离血红蛋白的含量,通常不超过红细胞总量的1.0%。特殊需求的红细胞产品又有额外的要求。每单位少白细胞的红细胞的残余白细胞不超过1×10~6。  相似文献   
19.
Dermatitis artefacta is a self-inflicted cutaneous disease presenting as sharply delineated ulcers, usually in accessible sites such as the head and neck. IgG4-related disease (IgG4-RD) is a recently recognised immune-mediated condition causing a fibroinflammatory process, resulting in the formation of tumefactive lesions in various organs, rarely presenting primarily in the skin. We report a case of cutaneous IgG4-RD clinically presenting as dermatitis artefacta.  相似文献   
20.
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