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31.
A pulmonary arteriovenous fistula is an abnormal connection between pulmonary arteries and veins. Patients with Rendu–Osler–Weber syndrome may present with this vascular malformation, which is a typical finding of the disease. Approximately 5–15% of Rendu–Osler–Weber syndrome patients have pulmonary arteriovenous malformations (AVM) and there is usually a family history of AVM in these patients. The malformations are usually located in the lower lobes. In this paper, I describe a 49‐year‐old male patient with dyspnoea, cough, haemoptysis and epistaxis. Physical examination showed nasal telangiectasias, cyanosis of the lips and nails, and a systolic bruit over the left lung. Chest X‐ray revealed a 5‐cm mass in the left lower lobe and after magnetic resonance examination, together with 3‐D magnetic resonance angiography, it was demonstrated to be a pulmonary arteriovenous fistula. The history of a niece with a similiar history of suspected pulmonary arteriovenous fistula led me to consider the possibility of Rendu–Osler–Weber syndrome presenting with a pulmonary arteriovenous fistula.  相似文献   
32.
Heterogeneity of B cell involvement in acute nonlymphocytic leukemia   总被引:2,自引:0,他引:2  
In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis.  相似文献   
33.
Charbord  P; Gown  AM; Keating  A; Singer  JW 《Blood》1985,66(5):1138-1142
The CGA-7, a monoclonal antibody that reacts with smooth muscle cell actin but not with endothelial cell or fibroblast actin, and HHF, a monoclonal antibody that reacts with smooth muscle, skeletal muscle, and cardiac muscle actin, both recognize microfilaments present within adherent cells from actively hematopoietic human long-term marrow cultures. Macrophages, monocytes, and cultured marrow fibroblasts do not react with either antibody. These data suggest that the anti-actin antibodies may serve as useful markers for in vitro microenvironmental cells and lend support to the hypothesis that stromal cells from long- term marrow cultures are different from marrow fibroblasts and may constitute a unique cell lineage.  相似文献   
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Background  

Early and intensive treatment is important to inducing remission and preventing joint damage in patients with rheumatoid arthritis. While intensive combination therapy (Disease Modifying Anti-rheumatic Drugs and/or biologicals) is the most effective, rheumatologists in daily clinical practice prefer to start with monotherapy methotrexate and bridging corticosteroids. Intensive treatment should be started as soon as the first symptoms manifest, but at this early stage, ACR criteria may not be fulfilled, and there is a danger of over-treatment. We will therefore determine which induction therapy is most effective in the very early stage of persistent arthritis. To overcome over-treatment and under-treatment, the intensity of induction therapy will be based on a prediction model that predicts patients' propensity for persistent arthritis.  相似文献   
37.

Two principles should underpin the provision of primary health care to refugees: (a) that refugees should have the same access to quality primary care services as the local population, and (b) any specialist service should have the goal of full integration of the refugee into normal general practice. The various ways in which medical care can be provided to refugees and the knowledge, skills and attitudes important to such provision are described. One way in which such a service was provided in east Kent is reported. The term ‘refugee’ encompasses newly arrived refugees who are awaiting a decision from the Home Office, as well as those who have been given permission to stay, either as recognized Refugees under the provisions of the 1951 United Nations Convention, or with Exceptional or Indefinite Leave to Remain.  相似文献   
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Summary Telomere length decreases with age and is associated with osteoblast senescence. In 2,150 unselected women, leukocyte telomere length was significantly correlated with bone mineral density. Clinical osteoporosis was associated with shorter telomeres, suggesting that telomere length can be used as a marker of bone aging. Introduction The length of telomeres in proliferative cells diminishes with age. Telomere shortening and telomerase activity have been linked to in vitro osteoblast senescence and to increased secretion of pro-inflammatory cytokines. We explored whether bone mineral density correlates with telomere length in leukocytes. Materials and methods The relationship between leukocyte telomere length, bone mineral density (BMD) and osteoporosis (as defined by the World Health Organization) was examined in a cohort of 2,150 women from a population-based twin cohort aged 18–79. Results After adjusting for age, body mass index, menopausal status, smoking, hormone replacement therapy status, telomere length was positively correlated with BMD of the spine (p < 0.005), forearm (p < 0.013), but not the femoral neck (p < 0.06). Longer telomeres were associated with reduced the risk of clinical OP at two or more sites (odds ratio = 0.594 95% CI 0.42–0.84 p < 0.003) and in women over the age of 50, clinical osteoporosis was associated with 117 bp shorter telomere length (p < 0.02) equivalent to 5.2 years of telomeric aging. Conclusions Shortened leukocyte telomere length is independently associated with a decrease in BMD and the presence of osteoporosis in women. Our data provide evidence that leukocyte telomere length could be a marker of biological aging of bone.  相似文献   
40.
Background Breast carcinoma is the most frequently diagnosed malignancy in women of the North America. The combination of breast-conservation surgery and radiotherapy has become a standard of treatment for most breast cancers. It is critical to obtain clear margins to minimize local recurrence. The literature suggests that intraoperative touch preparation cytology (IOTPC) can be useful in evaluation of margins. Invasive lobular carcinoma (ILC) accounts for 10% to 15% of all breast cancers. Obtaining clear margins in ILC can be more challenging. Literature shows the positive margin rate for ILC to be as high as 60%. This report describes our experience with IOTPC for margin assessment in ILC by a single surgeon at Beth Israel Medical Center. The purpose of this study is to determine whether IOTPC is reliable for ILC. Methods A prospective review of 73 patients who underwent breast-conservation surgery with the use of IOTPC for margin assessment at Beth Israel Medical Center was performed. Pathology revealed ILC in 12 of these patients (16.4%), who are the subjects of this study. The lumpectomy specimens were oriented by the surgeon intraoperatively and were submitted fresh to pathology for cytologic assessment. IOTPC consisted of touching the corresponding margin onto the glass slide. The principle of this technique is that if cancer cells are present, they will stick to the slide, whereas fat cells will not. Six slides were prepared for each lumpectomy specimen. Air-dried samples were stained immediately by the Diff-Quik method and examined under the microscope by a cytopathologist. Results Twelve patients with ILC underwent breast-conservation surgery with IOTPC for assessment of 72 margins. Ten patients had lobular carcinoma only, and the remaining two patients had a combination of lobular and ductal carcinoma. There was a correlation between IOTPC and final pathology in 60 of 72 margins, which accounted for 83.3% of the cases. IOTPC for assessment of margins in patients undergoing breast-conservation surgery for ILC has a sensitivity of 8.3%, specificity of 98.3%, positive predictive value of 50%, and negative predictive value of 84.3%. Conclusions On the basis of our experience, IOTPC is of limited value for intraoperative assessment of margins for ILC. Poster presentation at the Sixth Annual Meeting of the American Society of Breast Surgeons, March 16–20, 2005, Los Angeles, California.  相似文献   
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