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1.
Since we introduced angioscopy in autumn 1991 byin situ vein bypass operations we have used four different angioscopes with outer diameters of 2.2, 2.3, 2.8, and 2.9 mm. The 2.2 mm model was steerable, and collateral irrigation through a separate irrigation catheter was used. The other scopes had a built-in irrigation channel. Irrigation fluid was provided by a pressure cuff device placed around a liter of Ringer's acetate solution in plastic bag and inflated to between 200 and 300 mmHg. Recently we have used a roller pump that provides adjustment of the flow rate with a constant pressure of 200 mmHg. A Mills valve cutter was tested in the initial phase, but later the Insitucath proved more suitable. Valve disruption has been safe and confident. In addition, the angioscopy has been used as an adjuvant method in carotid endartectomies, thromboembolectomies, aortobifemoral reconstructions, iliacofemoral endarterectomies, in vascular access surgery, and percutaneous stent application. The visualization has been excellent or good and there have not been any significant complications due to the angioscopes. The use of angioscopy is well established in our arterial procedures and in the near future it will be introduced in venous surgery. The need for further studies concerning the significance of intraluminal findings is obvious.Presented at the 35th World Congress, International College of Angiology, Copenhagen, Denmark, July 1993  相似文献   
2.
We investigated the expression kinetics of several cytokines in trigeminal ganglia (TG) and in brains of BALB/c mice during the course of ocular herpes simplex virus type 1 (HSV-1) infection. All mice recovered from the infection within 2 weeks. The quantitative rapid real-time RT-PCR method was used to analyze interleukin-4 (IL-4), interferon-gamma (IFN-gamma), IL-12p35, IL-12p40, and the recently described IL-23 (p19) mRNA in TG, brain, and splenocyte samples. In TG, we found elevated expression of mRNA for IL-23 (p19) from early acute infection (day 3) to the beginning of the latent phase (day 14). The increase was not detected in brain or in the spleen. IL-4 expression occurred in both TG and brain from the beginning of the experiment to the latent phase. During the latent phase (days 14 and 31), IL-4 expression was significantly elevated in the brain when compared with the uninfected controls (p < 0.05). Considerable expression of IFN-gamma mRNA was detected in TG of mice during acute HSV-1 infection. The expression of IL-23 was detected also in the brains of the mice, even though no significant changes were found during the acute HSV-1 infection. This is, to our knowledge, the first report to show elevated expression of IL-23 (p19) mRNA (p < 0.05) during viral infection in TG of mice.  相似文献   
3.
BACKGROUND: Knowledge of the prevalence of peripheral arterial disease (PAD) in patients with chronic renal failure (CRF) is limited because of a lack of uniformity in disease definition and recognition. Furthermore, little is known of the prevalence of medial arterial calcification (MAC) in patients with CRF. Our goal is to study the prevalence of PAD and MAC defined by ankle brachial index (ABI) or toe brachial index (TBI) measurements in a Finnish population of patients with CRF consisting of predialysis and dialysis patients, as well as renal transplant recipients. METHODS: We examined 136 patients with CRF and 59 control subjects. Fifty-nine of the patients with CRF had moderate to severe predialysis CRF, 36 patients were on dialysis treatment, and 41 were renal transplant recipients. Mean age of patients was 51.9 +/- 11.5 years, and 39 patients (29%) had diabetes. ABI and TBI were measured by means of photoplethysmography. The definition of PAD required an ABI value of 0.90 or less, a TBI value of 0.60 or less, or a previous positive lower-extremity angiogram result. ABI values of 1.3 or greater or incompressible arteries at ankle level indicated MAC. The presence of claudication was determined by an interview. RESULTS: Prevalences of PAD on this study were 22.0% in patients with predialysis CRF, 30.6% in patients on dialysis treatment, 14.6% in renal transplant recipients, and 1.7% in the control group (P = 0.001). Prevalences of MAC were 23.7%, 41.7%, 23.1%, and 3.4% (P < 0.001), respectively. Only 9 patients had claudication, and 6 of those patients had PAD. CONCLUSION: Both asymptomatic PAD and MAC are common in patients with CRF. Therefore, we recommend the use of both ABI and TBI measurements in the evaluation of PAD in patients with CRF.  相似文献   
4.
5.
Hari R  Salenius S 《Neuroreport》1999,10(2):R1-10
Recent non-invasive human studies show that rhythmic oscillatory activity of the motor cortex and the firing of motor units of the muscle are coherent during isometric contraction, with peak frequencies around 20 Hz or 40 Hz, depending on the contraction strength. The cortical signals precede the motor unit firing and appear to reflect modulation of the common central drive to the spinal motoneuron pool. The rhythmic modulation may form a tool for efficient driving of motor units but we express some reservations about the assumed binding and attention-related roles of the rolandic brain rhythms. The cortex-muscle coherence is of interest for understanding of cortical control of voluntary movements and the pathophysiology of various motor disorders, as well as for unravelling the functional significance of cortical rhythms.  相似文献   
6.
BACKGROUND: Untreated chronic critical leg ischaemia (CLI) usually leads to an amputation or death of a patient. Surgical and endovascular interventions may improve arterial flow. Long infrainguinal reconstruction may be the most useful method for preventing amputations. The value of different reconstruction methods was assessed by their impact on amputation incidence. METHODS: A nationwide 2-year analysis of the incidence of major amputations and reconstructions for CLI was done in Finland (population 5.1 million). Incidences were compared in hospital regions with more than 150 000 inhabitants. RESULTS: The overall amputation incidence was 216 per million inhabitants per year. The corresponding incidence of arterial reconstructions was 203 per million inhabitants per year. There were large variations in the incidence of amputations and reconstructions; 20-fold differences in infrapopliteal surgical reconstructions and 30-fold differences in endovascular procedures were found. There was a correlation between a high incidence of infrapopliteal surgical reconstructions and a low incidence of amputations. This correlation was found for below-knee amputations only. CONCLUSION: These results suggest that long surgical reconstructions improving perfusion directly to the ischaemic tissue can improve leg salvage.  相似文献   
7.
Since total homocysteine (tHcy) level is markedly elevated in patients with chronic renal failure (CRF), it has been presented as a potential factor contributing to the high risk of cardiovascular disease (CVD) in CRF. Our aim was to examine the significance of elevated tHcy level and other cardiovascular risk factors for carotid atherosclerosis in patients with CRF. In this cross-sectional study, 135 study patients with CRF (52 +/- 11 years) included 58 patients with moderate to severe predialysis CRF, 36 dialysis patients and 41 renal transplant recipients. In addition, 58 control subjects were examined. The association of tHcy level and classic risk factors for atherosclerosis with common carotid artery intima-media thickness (IMT) or carotid artery plaque score was examined. We found no association between tHcy and carotid IMT or a high carotid plaque score in the CRF patient groups. No consistent association was found between elevated tHcy and coronary artery disease, cerebrovascular disease or peripheral arterial disease. Renal function, described as creatinine clearance, was the strongest determinant for tHcy level. Significant predictors of carotid atherosclerosis were age, duration of hypertension and elevated low-density lipoprotein cholesterol level. In conclusion, the present study shows no apparent association between tHcy level and atheromatous carotid findings in patients with CRF. However, because of the changing renal function in the course of renal disease, the strong confounding effect of renal function may not be adequately controlled for the analysis of the significance of elevated tHcy level for CVD in patients with CRF.  相似文献   
8.
Although DNA aneuploidy and high proliferative activity (S-phase fraction, SPF) of tumour cells, measured by flow cytometry, have proved to be indicators of poor prognosis in most solid tumours, there have been conflicting results in lung cancer studies. During a four-year period we studied the prognostic significance of DNA ploidy and SPF in 99 surgically treated lung cancer patients. Flow cytometric analysis was done from archival, formalin-fixed, paraffin-embedded tumour specimens. DNA index and SPF were determined, using MultiCycle software with sliced nuclear correction to compensate for debris. There were 61 DNA diploid and 38 DNA aneuploid tumours. The median SPF was 10.2%. Neither ploidy nor SPF was associated with previously known prognostic factors. Survival was poorer in patients with aneuploid tumours than in the other patients, but the difference was not statistically significant. DNA ploidy and SPF thus do not seem to be useful prognostic indicators in surgically treated lung cancer.  相似文献   
9.
Abstract

We evaluated the operative outcome in 22 consecutive patients who underwent microvascular decompression (MVO) of the intracranial portion of the cochlear nerve to relieve incapacitating tinnitus and related it to preoperative findings. The patients were selected for operation from the following criteria: severe tinnitus with sensorineural hearing loss and/or changes in brainstem auditory evoked potentials (BAEPs). Fifty percent had unilateral tinnitus. Before operation, 77 patients (77%) had sensorineural hearing loss in their affected ear. BAEPs were abnormal in 27 patients (95%) and acoustic middle ear reflex response was abnormal in six patients (27%). Vascular compression of the cochlear nerve was found in all patients during the operation. After the operation, 33% had relief of their tinnitus (two patients were totally free of tinnitus and five were markedly improved). Eight patients were slightly improved (38%), and the tinnitus did not change in four patients; two patients (70%) became worse. Of the patients with unilateral tinnitus, 63% had relief oftheir tinnitus. In one patient hearing was noticeably improved after the operation. Five patients (23%) had mild to moderate sensorineural hearing loss due to the operation. No other complications were detected. [Neural Res 1998; 20: 242-248]  相似文献   
10.
OBJECTIVE: The necessity of operative treatment of endotension after endovascular grafting of abdominal aortic aneurysms (endovascular aneurysm repair; EVAR) is under debate. The proposed causes of endotension and related treatment protocols are controversial. We report the outcome of a nonoperative approach to five patients with endotension after EVAR. METHODS: From February 1997 to August 2004, 160 patients who underwent EVAR of an infrarenal abdominal aortic aneurysm were evaluated for the incidence of endotension. According to the endovascular protocol, plain radiographs, spiral computed tomography, and angiography were performed before and after surgery for follow-up. To detect endotension, spiral computed tomography was performed by using a delayed imaging technique after the infusion of contrast medium. Endotension was defined as an aneurysm sac enlargement after EVAR without evidence of endoleak. Aneurysm sac rupture was defined as discontinuity of the calcific rim of the aneurysmal sac and the presence of intra-aneurysmal fluid outside the sac. RESULTS: We found five (3.1%) patients with endotension. Three of these experienced aneurysmal sac rupture. Only one of the three was underwent operation on experiencing sudden intestinal occlusion due to intra-abdominal adhesions. This patient had no intra-abdominal or retroperitoneal bleeding or hematoma but died after intensive care as a result of non-aneurysm-related problems. Four patients with endotension are still being closely followed up according to our surveillance protocol, and they are doing clinically well. After rupture, clear shrinking of the aneurysm sac was seen in two patients. CONCLUSIONS: Endotension after EVAR may cause subsequent aneurysm rupture. Endotension is evidently not associated with endoleak I to III provided that the endovascular graft is maintained in appropriate position and that free endovascular flow is observed. We propose to consider a nonoperative approach in the clinically asymptomatic patient with aneurysm enlargement after EVAR if endoleak is excluded by well-performed imaging techniques.  相似文献   
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