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1.
2.
The present study has been conducted to ascertain the level of allelic variation at codon 129 of the prion protein gene in France. Six French populations have been studied (Paris, Lille, Rennes, Chambéry, Grasse and Perpignan), totalling 1374 normal subjects. Mean heterozygosity in France is 46.5%, and the mean Met 129 allele (a high risk susceptibility factor for Creutzfeldt-Jakob disease) is 0.674. There is a genetic heterogeneity (chi(2)=38.44, p<0.001) between the six populations compared, and Met allele frequencies are inversely correlated with latitude (r=-0.93, p<0.01). Such an inverse correlation with latitude (r=-0.78, p=0.01) is also found when Met allele frequencies in France are compared to those already published in five other European countries and in Turkey. We hypothesise that high Met 129 frequencies populations may be at higher risk for Creutzfeldt-Jakob disease.  相似文献   
3.
The isolated azygos continuation of the inferior vena cave is a very rare variation of this organ. It is accompanied by the absence of the retrohepatic segment of the vena cava with two new observations, the literature is revised and the origin discussed.  相似文献   
4.
We describe a case of aortopulmonary fistula in which the correct diagnosis was made by transthoracic echocardiography. The transesophageal approach, because of severe aortic dilatation, failed to provide the correct diagnosis, underlining the importance of complete transthoracic and transesophageal studies in the evaluation of aortic aneurysms.  相似文献   
5.
Identification of 12 novel mutations in the CFTR gene   总被引:11,自引:0,他引:11  
Over 200 mutations, besides the deletion  相似文献   
6.
Physicians who treat multiple sclerosis (MS) face the challenge of patients exhibiting ongoing disease activity, including exacerbations, loss of functional capabilities, intellectual decline, and radiologic progression, despite being on a disease-modifying agent (DMA). After searching for factors that might at least in part explain these changes—such as nonadherent drug-taking behavior, or the presence of interfer-on-neutralizing antibodies—some providers may ultimately decide to switch the patient to another DMA. In most circumstances, patients likely derive only partial effects from these agents, even in the absence of compromising factors. Thus, a number of factors must be considered in order to intensify the treatment regimen in response to disease progression. In the context of an inadequate treatment response to a DMA, some clinicians will convert the patient to an alternative therapy, and others will instead use a second agent in combination with the first (the so-called platform agent). In the first of this two-part series, we explored the use of anti-inflammatory CS and ACTH to treat MS exacerbations. Although we underscored the limited availability of evidence-based studies to support specific regimens for this purpose, there is an even greater paucity of data to support the routine use of these agents in order to achieve chronic disease-modifying effects in those who continue to deteriorate clinically, radiographically, or both. Without doubt, a number of factors influence the formulation of combination treatment plan for MS. Nevertheless, we will focus on the rationale and practical schemes that can be considered for using corticosteroids (CS) (and perhaps even ACTH) in an attempt to modify various domains of ongoing disease activity.  相似文献   
7.
Ziel der vorliegenden Untersuchung war es, das Ausma? der Hornhautsch?digung durch eine Kataraktextraktion im Hinblick auf das Hornhautendothel und die Hornhautdicke zu untersuchen. Patienten und Methode: In einer prospektiven Untersuchung wurde die Entwicklung der Hornhautdicke und der Endothelzelldichte an 48 Patienten untersucht. Die Patienten wurden mittels Phakoemulsifikation operiert. Die Hornhautdicke wurde dabei mit einem Ultraschallpachymeter bei 12 Uhr und im Hornhautzentrum und die Endothelzelldichte mit einer Endothelzellkamera an den gleichen Me?punkten pr?operativ sowie 4 Wochen, 4 Monate und 1 Jahr postoperativ bestimmt. Ergebnisse: Ein Jahr postoperativ nahm die Hornhautdicke nach Phakoemulsifikation an der 12-Uhr-Position um ca. 9% und im Hornhautzentrum um ca. 12% im Vergleich zum pr?operativen Wert zu. Die Endothelzelldichte war 1 Jahr postoperativ an der 12-Uhr-Position um ca. 27% und im Zentrum um ca. 18% reduziert. Das Patientenalter korrelierte signifikant mit dem Zellverlust an beiden Me?punkten. Bezüglich der Dickenzunahme ist keine signifikante Korrelation festzustellen. Schlu?folgerung: Nach einer Kataraktextraktion ist der Hornhautstoffwechsel reduziert. Als Indikator k?nnen der Verlauf der Endothelzelldichte und der Dicke herangezogen werden.   相似文献   
8.
The Symptom Checklist-90-Revised (SCL-90-R) has often been used in studies of alcoholic populations. Based on findings reported in the literature and data gathered on 712 alcoholics in treatment, this paper investigates the general trends in the responses of alcoholics to the SCL-90-R. On global measures as well as on each of the symptom scales, the scores of alcoholic groups reveal a symptomatology two to five times as severe as that observed in the general population. The Psychoticism dimension shows the most marked divergence with the general population. In almost each of the study groups, the Depression Scale registers the highest scores, followed by Obsessive-Compulsive, Interpersonal Sensitivity, and Anxiety.  相似文献   
9.
The aim of this study was to characterize the role of the efflux transporter Mrp2 (Abcc2) in the pharmacokinetics of orally and intravenously administered pravastatin in rats. Eight Mrp2-deficient TR- rats and eight wild-type rats were given an oral dose of 20 mg/kg pravastatin. Four TR- animals and four wild-type animals were studied after intravenous administration of pravastatin (5 mg/kg). The TR(-) rats showed a 6.1-fold higher mean area under the plasma concentration-time curve (AUC) of pravastatin (p < 0.001) after oral administration and a 4.7-fold higher AUC (p < 0.01) after intravenous administration of pravastatin as compared with the wild-type animals. The mean systemic (total) clearance of pravastatin was 4.6-fold higher (39.2 versus 8.50 l/h/kg, p < 0.001) and the mean V 4.3-fold higher (14.1 versus 3.29 l/kg, p < 0.01) in the wild-type rats. The mean renal clearance of pravastatin in the TR(-) rats was 16.5-fold increased as compared with the wild-type animals (0.695 versus 0.042 l/h/kg, p < 0.05). The increased systemic exposure to oral pravastatin in the TR- rats was associated with a greater inhibitory effect on 3-hydroxy-3-methylglutaryl CoA reductase, as shown by smaller lathosterol to cholesterol concentration ratios. These results suggest that the reduced biliary pravastatin excretion in the Mrp2-deficient TR- rats is partly compensated for by increased urinary excretion of pravastatin. Furthermore, intestinal Mrp2 does not appear to play a major role in the oral absorption of pravastatin in normal rats.  相似文献   
10.
The purpose of this study was to examine the structural requirements of polychlorinated and polybrominated biphenyls (PCBs and PBBs) for altering tissue levels of retinoids. Seven congeneric PCBs and PBBs were studied: 3,3',4,4'-tetrachlorobiphenyl (TCB), 2',3,3',4,5- and 3,3',4,4',5-pentachlorobiphenyls (-PeCBs), 3,3',4,4'- and 3,3',5,5'-tetrabromobiphenyls (-TBBs), 2,2',3,3',5,5'-hexachlorobiphenyl (-HCB), and 3,3',4,4',5,5'-hexabromobiphenyl (-HBB). Male Sprague-Dawley rats were fed a vitamin A-adequate diet (1.3 mg/kg) for 30 days before being given a single IP injection of one of seven polyhalogenated biphenyls (150 mumol/kg) in corn oil (10 ml/kg) or vehicle alone. Rats were killed 1 week later. Except for 3,3',4,4',5,5'-HBB, all PCBs and PBBs studied significantly decreased serum retinol levels and, except for 3,3',4,4',5,5'-HBB and 2,2',3,3',5,5'-HCB, all PCBs and PBBs also lowered the serum retinol-binding-protein (RBP) content. The activity of hepatic retinyl ester hydrolase (REH) was reduced by the treatment of 3,3',4,4',5-PeCB, 3,3',4,4'-TBB, and 3,3',4,4',5,5'-HBB. The levels of hepatic retinol were decreased by 2,2',3,3',5,5'-HCB, 2',3,3',4,5-PeCB, and 3,3',4,4',5-PeCB, while levels of hepatic retinyl palmitate were decreased by 2',3,3',4,5-PeCB, 3,3',4,4',5-PeCB, 3,3',4,4'-TCB, 3,3',4,4'-TBB, and 3,3',4,4',5,5'-HBB. The substantial decreases in hepatic retinyl palmitate levels could not be explained solely on the basis of hepatomegaly caused by acutely toxic PCBs and PBBs. All halogenated biphenyls which caused a decrease in hepatic retinyl palmitate also caused an increase in renal retinyl palmitate except 3,3',4,4',5-PeCB. In summary, the acutely toxic (nonortho substituted) congeners had pronounced effects on hepatic, renal, and serum retinoids whereas other biphenyls only decreased serum retinol levels. The effects of these seven compounds on REH activity were not correlated with the effects on serum retinol or RBP levels. Therefore, this study shows that the structure-activity relationships for altering hepatic retinoids differ from those for serum retinol, implying the involvement of multiple mechanisms.  相似文献   
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