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51.
The talar beak is a well-described secondary sign of talocalcaneal coalition but is not pathognomonic of the condition and may be seen in other causes of restricted or abnormal subtalar motion. We present an unusual complication of talar beaks in two patients who sustained fractures through their beaks. One of the patients described did not have a talocalcaneal coalition but had developed a beak following a compound fracture dislocation of the ankle joint complicated by infection, a previously undescribed predisposing cause.  相似文献   
52.
The clinical research coordinator plays a crucial role in organizing a site's participation in the expanding arena of multicenter medical and pharmacologic clinical trials. This summary clarifies the role of the clinical research coordinator for inexperienced staff members assuming these responsibilities and outlines planning procedures leading to successful implementation. Emphasis is placed on establishing an interdependent relationship with the principal investigator, careful protocol assessment, team building, and staff feedback. Useful tools such as study manuals and physicians' study orders are described.  相似文献   
53.
A case study of multicentric reticulohistiocytosis is presented with extensive immunohistochemical studies of the infiltrate in both paraffin and cryostat sections. These studies showed that the cells are of monocyte/macrophage origin. B- and T-cell gene rearrangement analysis of multicentric reticulohistiocytosis was also performed and showed a germline configuration.  相似文献   
54.
55.
In order to ascertain the tamponade effect of air and silicone oil we examined the contact angles subtended by ex vivo human retina, Teflon and Perspex to find a suitable experimental material which would mimic the surface properties of the retina at a three-phase interface. Using the captive bubble technique to measure the contact angle, it was found that air subtended a larger contact angle (38.8°) with the retina than did silicone oil (18.2°). On coating the Perspex surface with protein (PCP), it was observed that the surface properties were modified such that PCP subtended contact angles with air (43.0°) and silicone oil (16.4°) similar to those subtended by ex vivo human retina. Using PCP as an experimental material that mimics ex vivo human retina, spherical chambers were employed in order to examine qualitatively and to quantify the arc of contact obtained with air and silicone oil. It was found that air gave a greater arc of contact for the same percentage fill than silicone oil.  相似文献   
56.
Calcium, cell signalling and cataract   总被引:5,自引:0,他引:5  
  相似文献   
57.
S D Sharp  R R Williams 《Cardiology》1992,81(4-5):207-212
The mechanism by which increased left ventricular (LV) mass leads to increased coronary heart disease morbidity and mortality is unknown. We evaluated the relation between fasting insulin and echocardiographic LV mass in hypertensives off medication and normotensive controls, controlling the analyses for blood pressure (BP) and body mass index (BMI). Fasting insulin (p = 0.0217) was the most significant predictor of LV mass in hypertensives, while BMI (p = 0.0265) and diastolic BP (p = 0.0159) were the only significant predictors of LV mass in controls. The relation between fasting insulin and LV mass was not confounded by obesity in hypertensives, but obesity and fasting insulin may interact to predict LV mass.  相似文献   
58.
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described.  相似文献   
59.
The management of patients presenting with supratentorial glioma between 1978 and 1986 is reviewed. Complete follow-up in 517 cases was obtained. One hundred and fifty eight patients were not submitted to any form of surgery, 299 patients were biopsied and 60 patients underwent craniotomy and internal decompression. The no surgery group contained a higher proportion of patients with poor prognostic indicators than either the biopsy or craniotomy groups. The craniotomy group consisted of patients with better prognostic indicators than the biopsy group, in particular, younger age and more favourable site, type and grade of tumour. This was reflected in the difference in outcome between the groups. Median survival was 14 months in the craniotomy group, four months in the biopsy group and 2.2 months in the no surgery group. The outcome in patients with histologically proven malignant gliomas was best in those patients who received radiotherapy. The craniotomy group had a median survival of 18.5 months, a two year survival of 48% and a five year survival of 9%. The median survival following radiotherapy of those patients with proven malignant gliomas who had a biopsy was 9.5 months with a two year survival of 16% and a five year survival of 2%. These results compare favourably with studies which have adopted a more aggressive approach, suggesting that outcome is determined as much by patient selection using favourable prognostic indicators as by the treatment itself. The need for prospective trials of the management of unselected consecutive glioma patients randomizing them to conservative and radical treatment groups in order to define the role of both conventional therapy and radical therapy is discussed.  相似文献   
60.
In the presence of fixed basal levels of insulin, the route of intravenous glucose delivery (protal vs. peripheral) determines whether net hepatic glucose uptake (NHGU) occurs. Our aims were to determine if the route of intravenous glucose delivery also plays a role in regulating NHGU in the presence of hyperinsulinemia and to determine if length of fast (18 vs. 36 h) influences regulation of NHGU. Five conscious dogs fasted 18 h were given somatostatin and replacement insulin (245 +/- 34 microU.kg-1.min-1) and glucagon (0.65 ng.kg-1.min-1) infusions intraportally. After a 40-min control period, the insulin infusion rate was increased fourfold, and glucose was infused for 3 h. Glucose was given either through a peripheral vein or the portal vein for 90 min to double the glucose load reaching the liver. The order of infusions was randomized. NHGU was measured with the arterial - venous difference technique. Insulin and glucagon levels were 12 +/- 2, 35 +/- 6, and 36 +/- 5 microU/ml and 55 +/- 12, 61 +/- 13, and 59 +/- 7 pg/ml during the control, peripheral, and portal infusions, respectively. The glucose infusion rate, the load of glucose reaching the liver, and the arterial-portal plasma glucose gradient were 0, 9.58 +/- 2.28, and 10.44 +/- 2.94 mg.kg-1.min-1; 29.4 +/- 3.6, 56.8 +/- 3.4, and 56.8 +/- 2.8 mg.kg-1.min-1; and 2 +/- 1, 5 +/- 1, and -51 +/- 15 mg/dl during the same periods.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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