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51.
The classical from of Wegener's granulomatosis (WG) is a necrotizing granulomatous angiitis that involves the upper and lower airways, and kidneys. A limited form of WG is characterized by pulmonary lesions identical to those of classical form WG without renal involvement. The authors report a case of limited form WG. A 58-year-old Japanese woman was admitted because of an abnormal pulmonary shadow. Pathological examination revealed granulomatous angiitis consistent with WG. No other organ involvement was found. The pulmonary shadow improved with cyclophosphamide therapy. The patient is now well and without evidence of exacerbation of the disease 18 month after the discharge. 相似文献
52.
During the past 3 years six episodes of ischemic monomelic neuropathy (IMN) have been identified in five patients as a complication of upper extremity dialysis grafts. All patients had long-standing insulin-dependent diabetes, peripheral neuropathy, and brachial artery graft origins, whereas 60% had peripheral vascular disease. Five episodes occurred immediately after graft placement, whereas one was due to a graft-related thromboembolus. Diagnostic delay was common with initial findings attributed to anesthesia, positioning, or surgical trauma. Electrophysiologic studies showed underlying diabetic neuropathy with severe multifocal neuropathy distal to the grafts. Digital pressure indices were reduced but there was no critical ischemia. In three cases ischemia was completely corrected with improvement in one. One patient had proximal balloon angioplasty with no improvement and of the two untreated patients, one improved slightly. Ischemic monomelic neuropathy is a rare but disabling complication of dialysis access in diabetic uremic patients. Its occurrence is unpredictable and diagnostic delay is common. Correction of ischemia is indicated but usually does not improve the neuropathy. Prevention requires further research to more accurately characterize the patients at risk.Presented at the Twelfth Annual Meeting of the Southern California Vascular Surgical Society, Coronado, Calif., September 17–19, 1993. 相似文献
53.
Poisoning due to class IA antiarrhythmic drugs. Quinidine, procainamide and disopyramide 总被引:4,自引:0,他引:4
Quinidine, procainamide and disopyramide are antiarrhythmic drugs in the class 1A category. These drugs have a low toxic to therapeutic ratio, and their use is associated with a number of serious adverse effects during long term therapy and life-threatening sequelae following acute overdose. Class 1A agents inhibit the fast inward sodium current and decrease the maximum rate of rise and amplitude of the cardiac action potential. Prolonged Q-T interval and, to a lesser extent, QRS duration may be observed at therapeutic concentrations of quinidine. With increasing plasma concentrations, progressive depression of automaticity and conduction velocity occur. 'Quinidine syncope' (a transient loss of consciousness due to paroxysmal ventricular tachycardia, frequently of the torsade de pointes type) occurs with therapeutic dosing, often in the first few days of therapy. Extracardiac adverse effects of quinidine include potentially intolerable gastrointestinal effects and hypersensitivity reactions such as fever, rash, blood dyscrasias and hepatitis. Procainamide produces electrophysiological changes that are similar to those of quinidine, although Q-T interval prolongation with the former is less pronounced at therapeutic concentrations. Hypersensitivity reactions including fever, rash and (more seriously) agranulocytosis are associated with procainamide, and a frequent adverse effect requiring cessation of therapy is the development of systemic lupus erythematosus. Of the 3 drugs, disopyramide has the most pronounced negative inotropic effects, which are especially significant in patients with pre-existing left ventricular dysfunction. As with quinidine, unexpected 'disopyramide syncope' at therapeutic concentrations has been described. Anticholinergic side effects are common with this drug and may require cessation of therapy. Disopyramide therapy may unpredictably induce severe hypoglycaemia. Severe intoxication with the class 1A agents may result from acute accidental or intentional overdose, or from accumulation of the drugs during long term therapy. Acute overdose can result in severe disturbances of cardiac conduction and hypotension, frequently accompanied by central nervous system toxicity. Decreased renal function can cause significant accumulation of procainamide and its active metabolite acecainide (N-acetyl-procainamide), resulting in severe intoxication. Mild to moderate renal dysfunction is less likely to lead to quinidine or disopyramide intoxication, unless renal failure is severe or concurrent hepatic dysfunction is present. Management of acute intoxication with class 1A drugs includes gut decontamination with provision of respiratory support and treatment of seizures as needed. Hypertonic sodium bicarbonate, by antagonising the inhibitory effect of quinidine on sodium conductance, may reverse many or all manifestations of cardiovascular toxicity.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
54.
Tae Kim Kristy S Hendrich Kazuto Masamoto Seong-Gi Kim 《Journal of cerebral blood flow and metabolism》2007,27(6):1235-1247
Quantifying both arterial cerebral blood volume (CBV(a)) changes and total cerebral blood volume (CBV(t)) changes during neural activation can provide critical information about vascular control mechanisms, and help to identify the origins of neurovascular responses in conventional blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI). Cerebral blood flow (CBF), CBV(a), and CBV(t) were quantified by MRI at 9.4 T in isoflurane-anesthetized rats during 15-s duration forepaw stimulation. Cerebral blood flow and CBV(a) were simultaneously determined by modulation of tissue and vessel signals using arterial spin labeling, while CBV(t) was measured with a susceptibility-based contrast agent. Baseline versus stimulation values in a region centered over the somatosensory cortex were: CBF=150+/-18 versus 182+/-20 mL/100 g/min, CBV(a)=0.83+/-0.21 versus 1.17+/-0.30 mL/100 g, CBV(t)=3.10+/-0.55 versus 3.41+/-0.61 mL/100 g, and CBV(a)/CBV(t)=0.27+/-0.05 versus 0.34+/-0.06 (n=7, mean+/-s.d.). Neural activity-induced absolute changes in CBV(a) and CBV(t) are statistically equivalent and independent of the spatial extent of regional analysis. Under our conditions, increased CBV(t) during neural activation originates mainly from arterial rather than venous blood volume changes, and therefore a critical implication is that venous blood volume changes may be negligible in BOLD fMRI. 相似文献
55.
Benjamin H. S. Lau Sharon K. Riesen Kim P. Truong Esther W. Lau Peter Rohdewald Ray A. Barreta 《The Journal of asthma》2004,41(8):825-832
A randomized, placebo-controlled, double-blind study involving 60 subjects, aged 6-18 years old, was conducted over a period of 3 months to determine the effect of Pycnogenol® (a proprietary mixture of water-soluble bioflavonoids extracted from French maritime pine) on mild-to-moderate asthma. After baseline evaluation, subjects were randomized into two groups to receive either Pycnogenol® or placebo. Subjects were instructed to record their peak expiratory flow with an Assess® Peak Flow Meter each evening. At the same time, symptoms, daily use of rescue inhalers (albuterol), and any changes in oral medications were also recorded. Urine samples were obtained from the subjects at the end of the run-in period, and at 1-, 2-, and 3-month visits. Urinary leukotriene C4/D4/E4 was measured by an enzyme immunoassay. Compared with subjects taking placebo, the group who took Pycnogenol® had significantly more improvement in pulmonary functions and asthma symptoms. The Pycnogenol® group was able to reduce or discontinue their use of rescue inhalers more often than the placebo group. There was also a significant reduction of urinary leukotrienes in the Pycnogenol® group. The results of this study demonstrate the efficacy of Pycnogenol® as an adjunct in the management of mild-to-moderate childhood asthma. 相似文献
56.
57.
原发性肝癌患者肝切除术前、后免疫细胞表型分析 总被引:1,自引:1,他引:0
目的研究原发性肝癌(PrimaryLiverCarcinoma,PLC)患者肝切除术前、后免疫细胞表型的变化。方法采用直接免疫荧光标记,流量血细胞计数法(FlowCytometry,FCM)检测方法,动态观察120例PLC患者肝切除术前后外周血T淋巴细胞亚群、NK细胞和HLA鄄DR含量变化。结果肝切除术前肝功能Child鄄PughB级、OGTTL型和术前施行肝动脉栓塞化疗患者外周血CD8+T细胞含量明显低于正常人组,CD4+/CD8+比值则较高(P<0郾05)。全部肝癌患者肝切除术前、后CD3+CD4+T细胞和NK细胞(CD3-CD16+CD56+)含量无明显差异。术后第1天、第3天、第7天和第2周外周血淋巴细胞CD3+CD8+含量明显低于肝切除术前和术后第3周(P<0.01);而CD4+/CD8+比值则显著高于肝切除术前和术后第3周(P<0郾01)。结论PLC合并肝硬变肝储备功能不足、术前肝动脉栓塞化疗和肝切除术可导致机体细胞免疫功能低下,PLC患者肝切除术前行肝动脉栓塞化疗的价值有待深入研究。 相似文献
58.
Dong Hwee Kim Yoon Kyoo Kang Miriam Hwang Ho Sung Jo Ki Hoon Kim 《Clinical neurophysiology》2004,115(5):1021-1026
OBJECTIVE: To evaluate the usefulness of the TenElectrodes, a new stimulator for inching test, in the diagnosis and localization of ulnar neuropathy at the elbow (UNE). METHODS: Sixty-two ulnar nerves in 40 control subjects and 24 ulnar nerves in 23 patients with typical symptoms and signs of UNE were studied. The inching test of ulnar motor nerve using TenElectrodes was done along 8 cm across the elbow in the extended position. RESULTS: In the inching test of the control group, the mean segmental latency difference was 0.19+/-0.08 ms. Maximal latency difference over a 1 cm segment did not exceed 0.40 ms in any of the controls but exceeded 0.5 ms or more in all clinical UNE patients. In all UNE patients, the lesion sites were identified by the inching test using TenElectrodes: the retroepicondylar groove (54.2%), the humeroulnar arcade (29.2%), and dual compression (16.6%). CONCLUSIONS: TenElectrodes is a useful stimulator for the inching test in the diagnosis of UNE. The precise localization of compression was possible in all patients with UNE and the most common site was the retroepicondylar groove. 相似文献
59.
Hyun Jik Kim Jinna Kim Joo-Heon Yoon 《European archives of oto-rhino-laryngology》2006,263(8):778-782
Olfactory neuroblastoma is a rare, malignant neoplasm arising from the olfactory epithelium. It has an aggressive biological behavior that is characterized by local recurrence, atypical distant metastasis, and poor long-term prognosis. The incidence of cervical lymph node metastasis in olfactory neuroblastoma is variable, and treatment modalities are controversial. Moreover, few reports have been published concerning retropharyngeal lymph node metastasis from olfactory neuroblastoma. We present two cases of olfactory neuroblastoma with retropharyngeal lymph node metastasis. In addition, we provided a review of the current literature regarding olfactory neuroblastoma and retropharyngeal lymph node metastasis from olfactory neuroblastoma. 相似文献
60.