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91.
92.
Intraoperative ultrasound examination of the brain   总被引:5,自引:0,他引:5  
In a preliminary demonstration of cranial intraoperative real-time ultrasound, both supratentorial and posterior fossa scans displayed the pertinent anatomy. A grade III astrocytoma was visualized on the supratentorial scan as well. Ultrasound may be valuable for surgical planning and biopsy procedures because of its reliable depiction of intracranial anatomy and ease of use.  相似文献   
93.
2010年8月,美国心脏病学会基金会(ACCF)、美国心脏学会(AHA)共同发布了美国食品药品管理局(FDA)关于氯吡格雷的"盒装警告",主要针对医师和患者提出建议,其内容包括:通过检测药物基因型以明确患者氯吡格雷的代谢变化,患者不良反应的风险,基因多态性对氯吡格雷的代谢及临床影响。  相似文献   
94.
BACKGROUND: Peripheral arterial disease is associated with a high incidence of cardiovascular mortality. Peripheral arterial disease can be detected by using the ankle-brachial index (ABI). This study assessed the prognostic value of the postexercise ABI in addition to the resting ABI on long-term mortality in patients with suspected peripheral arterial disease. METHODS: In this prospective cohort study of 3209 patients (mean +/- SD age, 63 +/- 12 years; 71.1% male), resting and postexercise ABI values were measured and a reduction of postexercise ABI over baseline resting readings was calculated. The mean follow-up was 8 years (interquartile range, 4-11 years). RESULTS: During follow-up, 1321 patients (41.2%) died. After adjusting for clinical risk factors, lower resting ABI values (hazard ratio per 0.10 lower ABI, 1.08; 95% confidence interval [CI], 1.06-1.10), lower postexercise ABI values (hazard ratio per 0.10 lower ABI, 1.09; 95% CI, 1.08-1.11), and higher reductions of ABI values over baseline readings (hazard ratio per 10% lower ABI, 1.12; 95% CI, 1.09-1.14) were significantly associated with a higher incidence of mortality. In patients with a normal resting ABI (n = 789), a reduction of the postexercise ABI by 6% to 24%, 25% to 55%, and greater than 55% was associated with a 1.6-fold (95% CI, 1.2-2.2), 3.5-fold (95% CI, 2.4-5.0), and 4.8-fold (95% CI, 2.5-9.1) increased risk of mortality, respectively. CONCLUSIONS: Resting and postexercise ABI values are strong and independent predictors of mortality. A reduction of postexercise ABI over baseline readings can identify additional patients (who have normal ABI values at rest) at increased risk of subsequent mortality.  相似文献   
95.
Patients with peripheral arterial disease (PAD) are at high risk of major ischaemic events. Long-term data of all major ischaemic events in PAD patients are scarce and outdated, especially for patients with severe PAD requiring bypass surgery. Our objective was to define their long-term prognosis and develop a prediction model which quantifies this risk up to a decade after surgery. We conducted a retrospective cohort study in patients from the Dutch Bypass Oral anticoagulants or Aspirin (BOA) Study; a multicentre randomised trial comparing oral anticoagulants with aspirin after infrainguinal bypass surgery. The primary outcome was the composite event of non-fatal myocardial infarction, non-fatal ischaemic stroke, major amputation, and vascular death. Cumulative risks were assessed by Kaplan-Meier analysis and independent determinants by multivariable Cox regression models. From 1995 until 2009, 482 patients were followed for a median period of 7.8 years. Follow-up was complete in 94%. Overall 60% of patients experienced a primary outcome event, of which the majority was a vascular death (30%), followed by major amputations (12%). The primary cause of vascular death was a cardiovascular event (29%), whereas the minority was due to complications directly related to PAD (6%). Within five years after bypass surgery vascular death occurred in about a quarter of patients and within 10 years in nearly half of patients. This was double the rate as for non-vascular death. The primary outcome event occurred in over a third and over half of patients in 5 and 10 years after bypass surgery, respectively. From four independent determinants for the primary outcome event: age, diabetes, critical limb ischaemia, and prior vascular interventions, we developed a risk chart, which systematically classifies the 10-year risks of the primary outcome event, ranging from 25% to 85%. This study provided a detailed insight in the course of PAD long after peripheral bypass surgery and enables individual risk assessment of major fatal and non-fatal ischaemic events by means of cumulative incidences and a risk chart.  相似文献   
96.
97.
When perfusion pressure is reduced, red blood cell flow in the capillaries of skeletal muscle ceases at a positive pressure difference across the vascular bed, while arterioles dilate and venules are not constricted. This flow cessation (i.e., cessation of red blood cell flow) and luminal diameter changes in capillaries following femoral arterial pressure reduction were investigated in the rabbit tenuissimus muscle in situ (n=42) using intravital video microscopy. Arterial pressure was reduced by occlusion of the aorta distal to the renal arteries. During the experiments, leg and muscle were placed in a sealed box. The muscle was exposed to low PO2 by leading a gas mixture deprived of O2 through the box. Locally at the muscle surface, i.e., under the microscope objective, PO2 was varied by varying the PO2 in the superfusion solution. In all experiments, the remainder of the muscle was kept at low (< 20 mm Hg) PO2. The incidence of flow cessation was virtually zero at low local (< 20 mm Hg) PO2 and became almost 100% at local values above 70 mm Hg. Initial equivalent capillary diameters were 3.1–5.8 m (median 4.0 m) and did not correlate with local O2 tension. During aorta occlusion, capillary diameters significantly (P < 0.0001) decreased by a median value of 8% at all local PO2 values; in 14 out of 54 capillaries local diameter became less than 2.8 m. The extent of diameter reduction did not correlate with PO2. In the 14 capillaries in which the diameter became less than 2.8 m flow cessation occurred in only four cases. The minimal diameter reached was always at the site of an endothelial nucleus. The capillary diameter reductions are probably due to passive recoil. In the 48 capillaries in which flow ceased, only in four cases did a red blood cell stop at the site of the nucleus. We conclude that capillary diameter reductions (local and generalized) lead to a considerable increase in capillary resistance which contributes to the occurrence of flow cessation but cannot solely explain it.  相似文献   
98.
Summary Highly reproducible anti glomerular basement membrane (GBM) nephritis has been induced in the mouse after a single injection of rabbit or goat antibody against purified homologous GBM. The severity of albuminuria was closely related to the amount of antibody given. With doses of 4 mg or more, low serum albumin concentrations, sometimes accompanied by ascites and oedema, were observed after 1 week. Glomerular injury was characterized by an initial accumulation of polymorphonuclear granulocytes followed by thrombosis and necrosis, the extent of which defined the outcome of the glomerulonephritis. With high doses of antibody the exudative lesions entered a chronic phase, while at doses lower than 2 mg remission of the lesions occurred. Immunofluorescence studies showed prompt linear fixation of the injected anti-bodies to the glomerular capillary wall, accompanied by immediate binding of C3 in a fine granular pattern. Fibrin deposits appeared at 2 h in some glomeruli, increased thereafter, and were present after one day in more than 90% of the glomeruli in mice that had received 4 mg of antibody. This new reproducible model in the mouse is suited for the study of the relationship between activation of mediator systems, histological lesions, and proteinuria.  相似文献   
99.
Summary The Heymann antigen (gp-330) and an antigen with lower molecular weight (gp-90) are major constituents of the brush border of the renal proximal tubules in the rat and the mouse. The Heymann antigen can also be found at discrete sites in the glomerular visceral epithelium of the rat, but not of the mouse. Gp-90 is present diffusely along the glomerular capillary wall of rat and mouse. The Heymann antigen is probably the target antigen for membranous glomerulonephritis in the rat, while in the mouse, where this form of glomerulonephritis can also be induced, gp-90 seems to be the antigen involved. We have separated the antibody populations against these two antigens by preparing eluates from kidneys of rats and livers of mice that had been injected with an antiserum against pronase-digested mouse renal tubular antigens. Using these purified antibodies we have examined by indirect immunofluorescence the distribution of the two antigens on normal mouse and rat tissues. The expression of the Heymann antigen is limited to the epithelia of several organs, while gp-90 has a more widespread distribution in many cells of different origin and function in both the mouse and the rat.  相似文献   
100.
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胆道系统恶性肿瘤包括胆管癌和胆囊癌 ,前者主要指原发于肝内、肝门部和远端肝外胆管的恶性肿瘤。至今胆系肿瘤仍依TNM分类法分为 0~Ⅳ期。 0期 :为原位癌 ;Ⅰ期 :肿瘤局限于粘膜层、肌层 ;Ⅱ期 :出现局部浸润 ;Ⅲ期 :在Ⅰ或Ⅱ期基础上肿瘤累及邻近组织或肝十二指肠韧带上淋巴结 ;Ⅳ期 :出现肝脏等器官受累或远处转移或出现以下之一区域的淋巴结转移 ,如胰周、十二指肠周、肝门周、腹腔及肠系膜。1 诊断胆系恶性肿瘤的诊断 ,主要依靠临床表现、实验室检查以及影象学检查。临床表现特异性不强 ,其中最基本的表现为胆道梗阻症状 ,同时可…  相似文献   
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