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Summary In chronic myeloproliferative disorders (CMPD) thrombohaemorrhagic complications occur occasionally in association with thrombocytosis. We studied the multimeric composition of plasma von Willebrand factor (vWf) in 15 patients with polycythaemia vera (PV), 12 with essential thrombocythaemia (ET) and eight with primary myelofibrosis (PMF). The relative content of large (multimer band ≥ 11) multimers calculated by densitometer scan following SDS-agarose gel electrophoresis was 18.5 ± 4.4% (mean±SD) in normal controls, 8.3 ± 7.9% in PV, 8.1 ± 4.6% in ET and 19.6 ± 6.7% in PMF. The patients with PV and ET but not PMF had a significantly lower percentage of large multimers than normal controls (P < 0.001). The relative content of large multimers was negatively correlated with WBC and platelet count (P < 0.02 each) in PV. It was negatively correlated with platelet count (P < 0.005) and was positively correlated with a ratio of ristocetin cofactor/vWf antigen (RCof/vWf: Ag)(P < 0.01) in ET. These results indicate that acquired defects of vWf are quite common in PV and ET but not in PMF. In addition, some CMPD patients with high platelet counts completely lacked large multimers. The negative correlation of the relative content of large multimers with platelet count suggests that large multimers may be preferentially consumed during thrombocytosis or degraded by protease(s) from increased blood cells.  相似文献   
84.
We report the first case of human herpesvirus-6 (HHV-6) associated exanthema in a patient with acute lymphocytic leukaemia (ALL). We analysed DNA extracted from an exanthematous lesion using the polymerase chain reaction (PCR). DNA was positive for HHV-6 but negative for herpes simplex virus, varicella zoster virus, and cytomegalovirus. Immunohistochemical staining of the skin with monoclonal antibody against HHV-6 confirmed the infection. The possibility of HHV-6 infection should be considered when an atypical skin rash is seen in patients with ALL.  相似文献   
85.
Coronary Vein Accessory Pathways. Introduction: Some posteroseptal accessory pathways (APs) can be successfully ablated by radiofrequency current only from inside the coronary sinus (CS) or its branches, because of an absolute or relatively epicardial location. The aim of this study was to identify ECG features of manifest posteroseptal APs requiring ablation in the CS or the middle cardiac veins (MCVs). Methods and Results: One hundred seventeen consecutive patients with manifest posteroseptal APs successfully ablated: (1) ≥ 1 cm deep inside the MCV (group MCV: n = 13); (2) inside the CS, including the area adjacent to the MCV ostium (group CS: n = 10); (3) at the right (group R: n = 60); or (4) the left posteroseptal endocardial region (group L: n = 34) were included. We reviewed delta wave polarity (initial 40 msec) and QRS morphology during sinus rhythm and atrial pacing as well as electrogram characteristics in these patients. The local target site electrogram in groups MCV and CS was characterized by a longer atrial to ventricular electrogram interval, suggesting a longer course of the pathway and more frequent recording of a presumptive AP potential compared to the group ablated at the right or left endocardium. The most sensitive ECG feature for group CS or group MCV was a negative delta wave in lead II in sinus rhythm (87%), but specificity (79%) and positive predictive value (50%) were relatively low. A steep positive delta wave in aVR during maximal preexcitation possessed the highest specificity and positive predictive value (98% and 88%, sensitivity 61%) which increased to 99% and 91%, respectively, when combined with a deep S wave in V6 (R wave ≤ S wave). Conclusion: These data suggest that posteroseptal APs ablated inside the coronary venous system have highly specific features, including the combination of a steep positive delta wave in lead aVR and a deep S wave in lead V6 (R wave ≤ S wave) during maximal preexcitation. The highest sensitivity is provided by a negative delta wave in lead II. These findings may be helpful for anticipating and planning an epicardial ablation strategy.  相似文献   
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Objective: This study examined the relationship between bothersome symptoms of nocturia and erectile function. Methods: Subjects comprised patients with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). Patients were prospectively followed on treatment with the alpha‐1 blocker naftopidil for 8 weeks. Patient backgrounds and efficacy of naftopidil associated with LUTS and sexual activity were evaluated. Results: The percentage of patients who identified nocturia as the most bothersome symptom was 30.2% (n = 135), representing the highest percentage among International Prostate Symptom Score (IPSS) items. The number of patients with nocturia as the most bothersome symptom plateaued at an IPSS for nocturia of two or three points. In contrast, the number of patients with slow stream as the most bothersome symptom increased with symptom severity according to IPSS for slow stream. Logistic regression analysis on association between nocturia and erectile function confirmed that the odds ratio was 1.41 (P < 0.05). Naftopidil showed excellent efficacy related to male LUTS, but International Index of Erectile Function 5 (IIEF5) total score was almost unchanged. Among patients with nocturia improved by naftopidil, IIEF5 total score was significantly changed in the group with IPSS nocturia score ≤1 as compared to the group with IPSS nocturia score ≥2 per night (P = 0.038). Conclusion: Nocturia the most bothersome symptom correlated with aging. Nocturia could associate erectile dysfunction, and keeping the frequency of nocturia at ≤1 episode might be meaningful for maintaining quality of life in elderly men.  相似文献   
88.
Abstract: Two patients with pneumatosis cystoides intestinalis (PCI) successfully treated with hyperbaric oxygen are described, The first patient was a 52-year-old male who presented with bloody stools and was diagnosed as having primary PCI. The second was a 61-year-old male whose occupation entailed prolonged exposure to trichloroethylene. Following hyperbaric oxygen therapy, the colonic gas cysts completely disappeared in both patients, and there has been no evidence of recurrence. The relevant literature from 1980 to 1992 is reviewed, and hyperbaric oxygen therapy for PCI is discussed in detail. The data accumulated thus far suggest that hyperbaric oxygen is superior to high-flow oxygen breathing in PCI therapy.  相似文献   
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The detection of cytokeratins in neoplastic tissues by immunohistochemical methods has numerous diagnostic and investigative applications, because cytokeratins are usually conserved in tumour cells during malignant transformation. Recently, however, it has been reported that progression to malignancy is associated with commencement of expression of low-molecular-weight cytokeratins. In the present study, 42 specimens from 35 cases of squamous cell carcinoma (SCC) of the skin were analysed by immunohistochemical techniques, using polyclonal anti-involucrin antibody and a panel of monoclonal antikeratin antibodies, in order to investigate the nature and differentiation of SCCs. The expression of cytokeratins and involucrin in well-differentiated SCCs was similar to that in normal epidermis. In contrast with well-differentiated SCCs, the expression of differentiation-specific cytokeratins and involucrin was diminished in the immature tumour cells in proportion to the malignancy of the SCCs. Some antibodies, however, stained all tumour cells, irrespective of the degree of malignancy. Furthermore, expression of simple epithelial and non-cornifying stratified squamous epithelial cytokeratins was observed in atypical tumour cells of poorly differentiated SCCs. It is of interest that similar expression was noted in many tumour cells in the lymph node metastases and in some tumour cells in the primary cutaneous lesions. Cytokeratin expression similar to that in normal epidermal keratinocytes was conserved in well-differentiated SCCs, but the expression of cytokeratins changed during progression to malignant transformation. The expression of simple epithelial or non-cornifying stratified squamous epithelial cytokeratins in cutaneous SCCs may be a marker for their capability of invasion and metastatic potential.  相似文献   
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