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Unilateral asterixis developed in a 56 year old man, 5 months after an infarct in the posterior cerebral artery territory, involving the posterolateral nuclear complex of the thalamus, documented by CT-scan and MRI. Unilateral asterixis in rarely reported in association with thalamic lesions and usually develops as an immediate postictal phenomenon. We discuss possible physiopathological mechanisms explaining the occurrence and the delayed onset of these involuntary movements.
Sommario Un uomo di 56 anni ha sviluppato un'asterixis unilaterale, 5 mesi dopo aver presentato un infarto nel territorio dell'arteria cerebrale posteriore, che coinvolgeva i nuclei postero-laterali del talamo, come evidenziato dalla TC e dalla MRI. Asterixis unilaterali si sviluppano raramente in seguito a lesioni vascolari a livello del talamo e generalmente rappresentano un evento immediatamente successivo all'ictus. Nel caso descritto invece, i movimenti involontari si sono manifestati a notevole distanza di tempo. Gli autori discutono i possibili meccanismi fisiopatologici alla base di questi movimenti involontari e della loro insorgenza a distanza di tempo dall'ictus.
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Lymph node (LN) metastases represent the most important negative prognostic factor in squamous cell carcinoma (SCC) of the oral cavity, even though controversies still exist regarding their management. The aim of this study was to retrospectively analyze our experience in surgical management of SCC of the oral cavity with particular focus on the prevalence and localization of lymph nodal metastases and recurrences. The clinical records of 89 consecutive patients treated from 1983 to 2002 by concomitant surgery on both the T and N sites, excluding those undergoing salvage surgery, were reviewed. A total of 119 neck dissections (ND) were performed. Survival outcomes were calculated by the Kaplan–Meier method, while univariate comparisons by the log-rank and non-parametric tests were performed between different groups of patients. Five-year overall and determinate survivals were 50 and 57%, respectively. LN metastases were observed in 52% (56% of these showing extracapsular spread) and their presence strongly correlated with determinate survival (p < 0.0001). The prevalence of clinical and occult nodal disease was not related to the pT status. Neck levels II (59%) and I (56%) were most frequently involved. Metastases to level IV accounted for 15% of positive LN, even though 28% of them turned out to be skip metastases. Five neck recurrences were observed, only one of which was salvaged by surgery. The high prevalence of clinical and occult LN metastases in this setting suggests that ND should be performed on a nearly routine basis, even for lesions with a low-T category and a cN0 neck. Moreover, ND should always encompass level IV due to the possibility of skip metastases, particularly in tumors involving the oral tongue. In patients with a cN+ neck, levels from I to V should be addressed, particularly in the presence of metastases at levels III and IV.  相似文献   
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We defined large striatocapsular infarcts as subcortical softenings of more than 20 mm in diameter involving the territories of the lateral and medial groups of lenticulostriate arteries. The aim of this study of 56 patients was to compare the clinical features and risk factors of these infarcts with those of cortical and lacunar infarcts. On the whole, our data suggest that both the clinical features and risk factors of large striatocapsular infarcts are similar to those of cortical infarcts, but significantly different from those of lacunar infarcts. The clinical manifestations of large striatocapsular infarcts with a maximum diameter of less than 50 mm may sometimes resemble those of lacunar infarcts because neuropsychological disorders are less frequent; however, our study indicates that, even in these cases, cardioembolic sources and artery-to-arteiy embolism are significantly more frequent in large striatocapsular than in lacunar infarcts, thus suggesting a different pathogenesis.  相似文献   
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In a randomized, double-blind parallel group study the 24-hour hypotensive effect of piretanide and its influence on biochemical variables were compared with those of placebo in patients with mild to moderate essential hypertension. Sixty patients entered the study, all of whom met the inclusion criteria (RRdiast between 95 and 120 mmHg). There was no drop-out during the study, so that the results of all 60 patients were statistically analysed. Piretanide produced a significant reduction of both systolic and diastolic blood pressure over 24 hours which was evident at four weeks and was maintained and further enhanced over the ensuing trial period. A mean maximal fall (at 12 weeks) of 10.7% (BPdiast supine) was observed. Placebo tablets did not produce any clinically relevant changes in systolic blood pressure, whereas a slight decrease was seen in diastolic blood pressure. This blood pressure reduction was significantly less in the placebo group than in the piretanide group at the end of the study (weeks 10 and 12). Dose doubling was needed in 13 of the 30 patients in the piretanide group, whereas as many as 20 out of 30 patients needed dose doubling in the placebo group. Pulse rate did not change relevantly during the trial in either group. A slight reduction in body weight was observed in the piretanide group. The mean values of serum potassium and sodium showed a slight decrease but remained within the normal range during the study period. A small increase in serum phosphorus was noted. None of these changes required any specific measures.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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 Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis. PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus. PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC (day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion, corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly were excluded from the study. Mean platelet content of the PC was 262×109 for BC-PC and 251×109 for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient platelet increment even when stored for up to 5 days. Received: 28 December 1995 / Accepted: 14 May 1996  相似文献   
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To compare rest-injected thallium-201 (Tl) redistribution and resting technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial uptake in chronic coronary artery disease (CAD), 15 patients with angiographically proven CAD and left ventricular (LV) dysfunction (ejection fraction 34%±9%) were studied. All patients underwent rest-redistribution Tl and resting 99mTc-MIBI cardiac imaging. Gated 99mTc-MIBI images were also acquired to assess regional LV wall motion (WM). Myocardial segments (n=225) were divided into three groups on the basis of the degree of coronary artery stenosis: group 1 (total occlusion, n=82), group 2 (50%–99% of stenosis, n=84) and group 3 (<50% of stenosis, n=59). WM was significantly worse in groups 1 and 2 compared to group 3 (P<0.001), but no difference was observed between groups 1 and 2. TI and 99mTc-MIBI uptake were significantly lower in groups 1 and 2 compared to group 3 (P < 0.001), and in group 1 compared to group 2 (P<0.001). When TI and 99mTc-MIBI uptake were directly compared, TI uptake was higher than 99mTc-MIBI uptake in group 1 (P<0.001), while no significant difference was observed in groups 2 and 3. Thus, both rest-injected TI redistribution and resting 99mTc-MIBI uptake reflected the severity of coronary artery stenosis in CAD. However, in myocardial segments with total coronary occlusion T1 uptake was significantly higher than 99mTc-MIBI uptake. Our data suggest that rest-injected Tl redistribution cardiac imaging may identify, more accurately than resting 99mTc-MIBI imaging, the presence of viable myocardium in chronic CAD, particularly when the coronary blood flow is severely impaired.  相似文献   
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