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101.
Summary— In order to test whether the β-adrenoceptor activity in rheumatic heart valvular disease depends on the ventricular load conditions, we determined their density and binding affinity to [125I]-iodocyanopindolol in lymphocytes, as well as plasma catecholamine and cAMP levels in 69 patients with regurgitant and stenotic lesions of the aortic and mitral valves. The patients were classified as having left ventricular pressure overload (LVP), left ventricular volume overload (LVV), mixed lesions (MOL) or right ventricular pressure overload (RVP). The β-adrenoceptor activity was determined by radioligand binding methods, catecholamines by high performance liquid chromatography using an electrochemical detector and cAMP by radioimmunoassay. The mean β-adrenoceptor density (Bmax) of the control group was 60.1 ± 9.5 /mol ( n = 29) per 106 lymphocytes. In the study population, the density was decreased by 83% in LVP, 78% in LVV, 87% in MOL and 86% in RVP. Plasma norepinephrine was elevated by 89% in LVP and 60% in MOL, epinephrine by 43% in LVP, 50% in VOL, 115% in MOL and 20% in RVP, while dopamine was not significantly changed, and cAMP was slightly elevated in all four groups. Screening for activating mutational changes in the G-protein gave negative results, possibly dissociating the elevation in plasma cAMP from stimulatory effects of such abnormalities in the Gs-protein signaling. These results show a significant attenuation in lymphocyte β-adrenoceptor density of patients with rheumatic heart valvular disease, irrespective of the type of the prevailing ventricular load conditions. The reduction in receptor density is accompanied by a significant increase in plasma norepinephrine levels in patients with a left ventricular pressure overload and epinephrine in those with volume overload.  相似文献   
102.
A mixed B-cell type centroblastic lymphoma with extraordinarily many histiocytes in a 68-year-old man is reported. Multiple skin tumours were the only clinical manifestation during the first 5 months. The disease then progressed to the lymph nodes, spleen, and parenchymal organs, but the bone marrow remained unaffected until death, 11 months after the onset of signs. C3d receptors were the only surface markers of the centroblasts. The histiocytes were normal with respect to morphology, muramidase staining, and Fc and C3b receptors. This highly unusual spread from skin to lymphoid and parenchymal organs is discussed in the light of lymphoid cell kinetics.  相似文献   
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A forty-six-year-old man presented with a two-month history of increasing neck pain of insidious onset. He received treatment from his familty doctor and chiropractor consisting of analgesics and manipulation respectively, both of which did not offer relief. The patient presented to University Hospital where plain radiographs and CT showed a pathological fracture of the C4 vertebral body. A neoplasm was suspected and surgical excision revealed a giant-cell tumour of bone. This type of neoplasm is rare in the spine and difficult to manage in this site. This case highlights some of the problems encountered in the treatment of giant-cell tumour of the spine.  相似文献   
107.
Background: Carotid cavernous fistulae are treatable by various means, one of which is embolization via the superior ophthalmic vein (SOV). The use of this technique over the past 12 years at the Royal Melbourne Hospital, Victoria, Australia, is reviewed.
Methods: Five patients with carotid cavernous fistulas were treated with embolization of the fistula via the surgically isolated SOV.
Results: Each patient had successful endovascular closure of the fistula using embolization via the SOV approach.
Conclusions: Treatment of certain types of carotid cavernous fistulas that cannot be closed by the conventional endovascular (arterial and venous) approaches can be successfully closed by using a transvenous approach through the SOV  相似文献   
108.
Over a 17-month period we prospectively recorded identifiable congenital malformations at delivery in singleton births in our hospital. Despite the prevailing religious and cultural belief we carried out autopsies in 41% of the perinatal deaths that occurred during the study period. Out of a total of 63 (21/1000 singleton births) congenital malformations discovered, 21 (33%) were identified at autopsy only. About 16% of total perinatal deaths were due to congenital malformation. Cardiovascular malformations accounted for about 40% of perinatal deaths from congenital malformations followed by central nervous system malformation (23.3%), gastrointestinal malformations (20%), musculo-skeletal malformations (6.7%); renal malformations (3.3%) and others (6.7%). No relationship between maternal age, parity and congenital malformation was found. The results from this study suggest that with the use of autopsy, teratology may contribute significantly to the prevailing high perinatal mortality in Lagos more than was previously thought.  相似文献   
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