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1.
Oral lichenoid drug eruptions   总被引:1,自引:0,他引:1  
OBJECTIVES: To identify, from amongst drugs reported as causing lichenoid drug eruptions, those affecting the oral mucous membranes and to review the clinical, histo-logical and immunological features of such oral lichenoid drug eruptions in comparison to oral lichen planus, amalgam contact lesions and lichen planus-like eruption in graft-versus-host disease (GVHD).
DATA SOURCES: Ovid® Medline data searches on CD-Rom were carried out for the years 1966–1996 to identify reports of oral lichenoid drug eruptions and their clinical, histological and immunological featureS. Articles retrieved were examined for further appropriate references in the period 1940–1996.
DATA EXTRACTION AND SYNTHESIS: Each paper was critically examined for evidence of a clinically verifiable lichenoid drug eruption affecting the oral mucous membranes and the effects of subsequent drug withdrawal. Available clinical, histological and immunological features were recorded. The papers examined were too diverse in nature to permit a structured criticism. The extracted data have been tabulated where appropriate.
CONCLUSIONS: The reports of oral lichenoid drug eruptions are considerably fewer than those of cutaneous eruptions and fewer drugs have been reported as causing oral rather than cutaneous lichenoid eruptionS. Histology and immunology cannot be used reliably to differentiate lichenoid drug eruptions from idiopathic lichen planus, amalgam contact lesions and lichen planus-like eruption in GVHD. Lichenoid drug eruptions may also show some histological characteristics of oral discoid lupus erythematosuS. An accepted protocol agreed by a number of international centres would permit the gathering of substantial information on LDE and could lead to a greater understanding of the mechanisms involved.  相似文献   
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Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.  相似文献   
4.
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools.  相似文献   
5.

Aim

Review the literature from 1990 to 2013 to determine known anatomic sites, risk factors, treatments, and outcomes of head and neck squamous cell carcinoma (HNSCC) in sub-Saharan Africa.

Methods

Using a systematic search strategy, literature pertaining to HNSCC in sub-Saharan Africa was reviewed and patient demographics, anatomic sites, histology, stage, treatment, and outcomes were abstracted. The contributions of human immunodeficiency virus (HIV), human papillomavirus (HPV) and behavioural risk factors to HNSCC in the region were assessed.

Results

Of the 342 papers identified, 46 were utilized for review, including 8611 patients. In sub-Saharan Africa, the oropharyngeal/oral cavity was found to be the most common site, with 7750 cases (90% of all cases). Few papers distinguished oropharyngeal from oral cavity, making identification of possible HPV-associated oropharyngeal squamous cell carcinoma (SCC) difficult. SCC of the nasopharynx, nasal cavity, or paranasal sinuses was identified in 410 patients (4.8% of all cases). Laryngeal SCC was found in 385 patients (4.5% of all cases), and only 66 patients (0.8% of all cases) with hypopharyngeal SCC were identified. In 862 patients with data available, 43% used tobacco and 42% used alcohol, and reported use varied widely and was more common in laryngeal SCC than that of the oropharyngeal/oral cavity. Toombak and kola nut use was reported to be higher in patients with HNSCC. Several papers reported HIV-positive patients with HNSCC, but it was not possible to determine HNSCC prevalence in HIV-positive compared to negative patients. Reports of treatment and outcomes were rare.

Conclusions

The oropharyngeal/oral cavity was by far the most commonly reported site of HNSCC reported in sub-Saharan Africa. The roles of risk factors in HNSCC incidence in sub-Saharan Africa were difficult to delineate from the available studies, but a majority of patients did not use tobacco and alcohol.  相似文献   
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Outcome in haematological patients who develop critical illness has significantly improved over the last two decades, but less so in allogeneic BMT recipients. We prospectively investigated the outcome of 44 haematological patients with allogeneic BM or haematopoietic SCT (ABMT/AHSCT) requiring admission to the intensive care unit (ICU) of Ghent University Hospital between January 2000 and December 2007. We related outcome to the cause of critical illness, which was categorized as documented or clinically suspected bacterial infection, non-bacterial infection and non-infectious disease. Mechanical ventilation was required in 32 patients, and 12 patients received renal replacement therapy. Overall ICU-mortality, in-hospital mortality and 6-month mortality rates were 61, 75 and 80%, respectively. Hospital mortality rates in patients with bacterial infection (n=14), non-bacterial infection (n=13) and non-infectious disease (n=17) were 43, 85 and 94% (P=0.003). After adjustment for severity of illness sequential organ failure assessment (SOFA) score, bacterial infection (odds ratio 0.06, 0.01-0.36, P=0.002) was associated with significantly lower odds for hospital mortality. On the basis of our experience, ICU referral of ABMT/AHSCT patients is justifiable, as an acceptable fraction of these patients have longer-term survival. Documented or clinically suspected bacterial infection as the cause of critical illness is associated with better prognosis in comparison with other causes.  相似文献   
8.
Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies.  相似文献   
9.
车彪 《中国厂矿医学》2011,24(7):635-636
髋关节骨性关节炎是一种慢性进行性骨关节病,也是骨科常见疾患,多见于老年人,发病率随年龄增大而增高;是以慢性进行性软骨变性和软骨下及关节周围新骨形成为主要特点的退行性疾病。随着人口老龄化,越来越多的人患有髋关节骨性关节炎。  相似文献   
10.
Epstein–Barr virus (EBV) is a ubiquitous gamma‐herpesvirus that establishes a lifelong persistent infection in the oral cavity and is intermittently shed in the saliva. EBV exhibits a biphasic life cycle, supported by its dual tropism for B lymphocytes and epithelial cells, which allows the virus to be transmitted within oral lymphoid tissues. While infection is often benign, EBV is associated with a number of lymphomas and carcinomas that arise in the oral cavity and at other anatomical sites. Incomplete association of EBV in cancer has questioned if EBV is merely a passenger or a driver of the tumorigenic process. However, the ability of EBV to immortalize B cells and its prevalence in a subset of cancers has implicated EBV as a carcinogenic cofactor in cellular contexts where the viral life cycle is altered. In many cases, EBV likely acts as an agent of tumor progression rather than tumor initiation, conferring malignant phenotypes observed in EBV‐positive cancers. Given that the oral cavity serves as the main site of EBV residence and transmission, here we review the prevalence of EBV in oral malignancies and the mechanisms by which EBV acts as an agent of tumor progression.  相似文献   
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