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1.
Summary A patient who developed a unilateral opercular syndrome following a cerebrovascular accident is described. Computed tomography showed that the lesion did not affect the opercular cortex, but involved deep white matter and the head of the caudate nucleus of the left hemisphere. Persistent hypophonia and transient aphasia were associated. Comparison with previous cases is discussed.  相似文献   
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Summary The present report compares the effects of different membrane phospholipid (PL)-cholesterol compositions on the kinetics of liposome-mediated formation of calcium phosphates from metastable solutions (2.25 mM CaCl2; 1.5 mM KH2PO4) at 22°C, pH 7.4 and 240 mOsm. In most experiments, the liposomes were composed of 7:2:X mixtures of phosphatidylcholine (PC), neutral or acidic phospholipids, and cholesterol (Chol, X=0, 10, 35, or 50 mol%). The neutral phospholipids (NPL) examined, in addition to PC, were phosphatidylethanolamine (PE) and sphingomyelin (Sph), and the acidic phospholipids (APL) examined were dicetylphosphate (DCP), dioleolylphosphatidylglycerol (DOPG), dioleolylphosphatidic acid (DOPA), phosphatidylserine (PS) and phosphatidylinositol (PI). The 7:2:X liposomes did not initiate mineralization in metastable external solutions per se or, with the exception of DOPA, show extensive Ca-PL binding. However, solution Ca2+ losses due to precipitation occurred when the liposomes were encapsulated with 50 mM KH2PO4 and made permeable to external Ca2+ with X-537A. The extent of these Ca2+ losses was sensitive to both the phospholipid and Chol makeup of the membrane. Moderate-to-extensive intraliposomal precipitation occurred in all 7PC:2APL and 7PC:2NPL liposomes containing 0 or 10 mol% Chol. In contrast, at 50 mol% Chol, mineralization inside all liposomes was negligible. The only significant discriminating effect on internal mineralization among the different phospholipids was observed at 35 mol% Chol, where mineral accumulations ranged from negligible to moderate. At 0 or 10 mol% Chol, extraliposomal precipitation was extensive in all but DOPA- and PS-containing liposomes. However, onece intraliposomal yields declined at the higher Chol levels, external mineralization was either delayed or totally blocked in all liposome preparations. Other experiments showed that Sph substituted for PC in 7NPL:2DCP:1Chol liposomes totally blocked both intra- and extraliposomal precipitaiton. PE substituted in this manner, however, blocked only extraliposomal precipitation. The results of this study suggest that interference of the membrane transport processes controlling intraliposomal precipitation [15] by high (50 mol%) Chol levels is not significantly compromised by the specific APL or NPL incorporated in the membrane. Similarly, the data suggest that Chol does not directly affect the specfic interactions of the different membrane APLs with the mineral phase. On the other hand, the substitution of other NPLs for PC can affect the role of APLs such as DCP in liposome-mediated mineralization.  相似文献   
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Empty Sella and Headache   总被引:2,自引:0,他引:2  
SYNOPSIS
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology.  相似文献   
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Data on the prevalence of antibody to hepatitis C virus among 278 subjects in an institution for the mentally handicapped were analysed by risk factors. A prevalence of 4% was found, higher than blood donors belonging to the same area (1.4%). No differences in prevalence with regard the length of residence, age, sex, degree of retardation or for presence of HBV markers were observed.  相似文献   
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The afferent nervous supply to the thymus gland has been investigated by means of the retrograde transport of horseradish peroxidase. It has been shown that the thymus receives an afferent supply from the nodose ganglia of the vagus and from the dorsal root ganglia C1–C7. The afferent innervation of the right and left thymic lobes is bilaterally organized; the fibers of a small celled population of nodose ganglion neurons cross outside the thymus and those of a larger celled population cross within the thymus gland. The functional implications of these findings are discussed in the context of central nervous system-immune system interactions.  相似文献   
8.
The quality of health care systems and processes is becoming a prominent problem and more and more efforts are devoted to define methodologies and tools to measure and assure quality of care. New methods are required to optimize health care processes to guarantee high quality standards within (limited) available resources. Resource optimizations able to preserve the quality of treatments require good models of medical processes. This paper presents LEMMA, a new notation to model medical processes. LEMMA provides physicians with intuitive graphical elements to design their models. At the same time a high level timed Petri net corresponding to the designed model is built automatically. In this way, LEMMA models are ascribed formal semantics and can be executed and analyzed automatically. The dual language approach followed in this paper allows physicians to gain all the benefits of formal methods without being proficient in them. Medical users manage simple graphical elements, while Petri nets ensure formality and validation capabilities. In this way LEMMA mixes formal and informal notations, overcoming the problems of both the approaches. The definition of the notation has been supported by the development of an environment to design LEMMA models. The environment, besides letting us experiment with the notation, has been employed to define and analyze real case studies.  相似文献   
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Nonmotor symptoms (NMS) of Parkinson's disease (PD) are not well recognized in clinical practice, either in primary or in secondary care, and are frequently missed during routine consultations. There is no single instrument (questionnaire or scale) that enables a comprehensive assessment of the range of NMS in PD both for the identification of problems and for the measurement of outcome. Against this background, a multidisciplinary group of experts, including patient group representatives, has developed an NMS screening questionnaire comprising 30 items. This instrument does not provide an overall score of disability and is not a graded or rating instrument. Instead, it is a screening tool designed to draw attention to the presence of NMS and initiate further investigation. In this article, we present the results from an international pilot study assessing feasibility, validity, and acceptability of a nonmotor questionnaire (NMSQuest). Data from 123 PD patients and 96 controls were analyzed. NMS were highly significantly more prevalent in PD compared to controls (PD NMS, median = 9.0, mean = 9.5 vs. control NMS, median = 5.5, mean = 4.0; Mann-Whitney, Kruskal-Wallis, and t test, P < 0.0001), with PD patients reporting at least 10 different NMS on average per patient. In PD, NMS were highly significantly more prevalent across all disease stages and the number of symptoms correlated significantly with advancing disease and duration of disease. Furthermore, frequently, problems such as diplopia, dribbling, apathy, blues, taste and smell problems were never previously disclosed to the health professionals.  相似文献   
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