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941.
Human immunodeficiency virus (HIV)-1 infection is associated with the development of aggressive extranodal B-cell non-Hodgkin's lymphomas. Using microvascular endothelial cell (MVEC)-enriched bone marrow stromal cultures, HIV infection of stromal MVECs from lymphoma patients induced the outgrowth of malignant B cells. MVECs were the only HIV-infected cells in the stroma, and purified brain MVECs also induced a phenotype supportive of neoplastic B-cell attachment and proliferation. HIV infection of MVECs stimulated surface expression of CD40 and allowed preferential induction of the vascular cell adhesion molecule VCAM-1 after CD40 triggering. B-lymphoma cells expressed the CD40 ligand (CD40L), and blocking of CD40-CD40L interactions between HIV-infected MVECs and B-lymphoma cells inhibited B-cell attachment and proliferation. These observations suggest that HIV promotes B-lymphoma cell growth through facilitating attachment of lymphoma cells to HIV-infected MVECs and represent a novel mechanism through which viruses may induce malignancies.  相似文献   
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A 73-year-old male was admitted to our hospital because of productive cough and infiltrate on the chest roentogenogram. The underlying diseases was found to be multiple myeloma. He received a physical examination in June, 1996. The chest X-ray and CT scan on admission showed an infiltrative shadow with multiple bulla in the left upper lung field. Internal use of antibiotics and drip infusion of IPM/CS were ineffective. The chest X-ray showed air-fluid level in left upper peripheral bullous lesion and a percutaneus needle aspiration of the lung was performed. The specimen was pus with blood and microscopical examination of smears revealed no acid-fast bacilli, but Mycobacterium szulgai was isolated and identified by DNA-DNA hybridization method. The patient was treated with isoniazid and rifampicin, and improved in a few months. There are a few case reports of pulmonary infection due to M. szulgai associated with emphysematous bulla of the lung in Japan. M. szulgai infection of the lung is similar to M. kansasii infection in respect to clinical features (improvement of chest abnormal shadow, efficacy of drug).  相似文献   
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OBJECTIVE: To compare endocardial and midwall measurement of left ventricular fractional shortening in assessing cardiac systolic function in hypertension. SETTING: Seventeen hypertension clinics in northeast Italy. MAIN OUTCOME MEASURES: Left ventricular endocardial fractional shorteningcircumferential stress relationship versus midwall shortening-stress relationship in the subjects divided according to relative wall thickness (RWT) and left ventricular mass indexed by body surface area. PATIENTS: Borderline-to-mild hypertensives [n = 635, aged 33 +/- 0.3 years (mean +/- SEM), office blood pressure 146 +/- 0.4/94 +/- 0.2 mmHg (means +/- SEM)] in the Harvest Study and 50 normotensive controls with similar age and sex distributions. METHODS: Blood pressure was measured by 24 h ambulatory monitoring. Left ventricular dimensional and functional indices were assessed by M-mode echocardiography. RESULTS: In the subjects divided into quintiles of RWT, the left ventricular shortening-stress relationship was increased in a parallel fashion when calculated by endocardial and by midwall measurements for RWT < or = 0.35. Instead, for greater RWT values (> or = 0.37) endocardial measurement constantly gave large values than did midwall measurement. Both the endocardial and the midwall shortening-stress relationships progressively decreased with increasing RWT. However, the endocardial shortening-stress relationship remained greater than normal at any RWT, whereas the midwall shortening-stress relationship was decreased for RWT > or = 0.37. In a multiple-regression analysis RWT was the most potent predictor of the endocardialmidwall shortening difference, left ventricular mass and 24 h systolic blood pressure being the second and third most potent predictors. CONCLUSIONS: We found a parallel increase in indices of cavity emptying and of myocardial contractility in mild hypertensive subjects with normal left ventricular geometry. When the RWT is increased, ejection phase indices may be normal in the presence of decreased myocardial contractility.  相似文献   
946.
A total of 159 operations for the excision of a preauricular sinus carried out in 117 patients over an 8-year period were reviewed. Previous excision, the use of a probe to delineate the sinus and operating under local anaesthesia all increased the chance of recurrence. The condition recurred more often in patients who developed post-operative wound sepsis than in those who healed primarily. Means of decreasing the recurrence rate include: (1) meticulous dissection of the sinus by an experienced head and neck surgeon under general anaesthesia; (2) the use of an extended preauricular incision; (3) clearance down to the temporalis fascia to ensure complete removal of all epithelial components; (4) avoidance of sinus rupture; and (5) closure of wound dead space.  相似文献   
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OBJECTIVES: To investigate whether the frequency of chromosome abnormalities in peripheral blood lymphocytes defined as the aneuploidy index in blood (AnIB) can be used as a clinical marker of early age onset, androgen response, and metastasis in human prostate cancer. METHODS: Peripheral blood samples were collected from 80 patients with prostate cancer, and chromosome preparations were made from 72-hour cultures after mitotic block. The AnIB of 59 informative cases was compared with several parameters, including age at disease onset, Gleason grade of tumor, clinical stage of tumor, metastasis, and prostate-specific antigen (PSA) level. RESULTS: Patients with AnIB levels greater than 3 had a significantly higher incidence of metastasis (P = 0.022), androgen-independent disease (P = 0.002), and early age at disease onset (age at diagnosis less than 65 years) (P = 0.002) compared with the patients with lower AnIB (less than 3) levels. In addition, patients with AnIB levels greater than 5 had higher PSA levels (greater than 20 ng/mL) (P = 0.029) than patients with AnIB levels less than 5. CONCLUSIONS: Chromosome abnormalities can be detected in the peripheral lymphocytes of patients with prostate cancer, and AnIB can be used as an early diagnostic and predictive marker for prostate cancer metastasis and androgen-independent disease.  相似文献   
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