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61.
To determine the prevalence of excessive daytime sleepiness (EDS) and that of dozing and sudden onset of sleep episodes (SOS) while driving in ambulatory patients with Parkinson's disease (PD) in France, a national sample of private and public neurologists was asked to recruit the first 10 consecutive nondemented PD patients. Each patient completed a questionnaire including the Epworth Sleepiness Scale (ESS) and the likelihood of dozing off and experiencing SOS episodes behind the wheel. Clinical and demographic data were collected. One thousand six hundred and twenty‐five patients with PD were included in the survey. Twenty‐nine percent of the patients suffered from EDS (ESS score ≥10) but only 0.8% declared a high chance of dozing while driving and 0.5% reported totally unpredictable SOS episodes while driving. Risk factors for EDS were male gender, reduced activity of daily living, and a high daily levodopa equivalent dosage. Risk factors for SOS episodes while driving were an ESS score ≥10, male gender, and low Hoehn and Yahr staging. EDS is common in ambulatory patients with PD and is a major risk factor for dozing and for SOS episodes behind the wheel in patients who drive. © 2007 Movement Disorder Society  相似文献   
62.
Current treatment of acute stroke remains unsatisfactory. This review presents experimental and clinical data which suggest that mild induced hypothermia could be a potent and practicable neuroprotective treatment of acute ischaemic stroke and intracerebral haemorrhage. Hypothermia, if proven to be safe, effective and widely practicable in patients with acute stroke, could have an enormous positive impact on reducing the burden of stroke worldwide. Critical issues that will need to be considered in a well designed randomised controlled trial of induced hypothermia in acute stroke patients are discussed.  相似文献   
63.
Low concentrations of N-nitrosodimethylamine are metabolized in rodent and human liver by cytochrome P450IIE1, an activity competitively inhibitable by ethanol. In rodents coadministration of ethanol with N-nitrosodimethylamine results in increased tumorigenicity in extrahepatic organs, probably as a result of reduced hepatic clearance. To test this concept in a primate, the effects of ethanol cotreatment on the pharmacokinetics of N-nitrosodimethylamine were measured in male patas monkeys. Ethanol, 1.2 g/kg given p.o. before i.v. N-nitrosodimethylamine (1 mg/kg) or concurrently with an intragastric dose resulted in a 10-50-fold increase in the area under the blood concentration versus time curves and a 4-13-fold increase in mean residence times for N-nitrosodimethylamine. Isopropyl alcohol, 3.2 g/kg 24 h before N-nitrosodimethylamine, also increased these parameters 7-10-fold; this effect was associated with persistence of isopropyl alcohol and its metabolic product acetone, both IIE1 inhibitors, in the blood. While no N-nitrosodimethylamine was detected in expired air, trace amounts were found in urine. Ethanol and isopropyl alcohol pretreatment increased the maximum urinary N-nitrosodimethylamine concentration 15-50-fold and the percentage of the dose excreted in the urine by 100-800-fold. Thus ethanol and isopropyl alcohol greatly increase systemic exposure of extrahepatic organs to N-nitrosodimethylamine in a primate.  相似文献   
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Transvaginal sonography of cervical width and length during pregnancy.   总被引:1,自引:0,他引:1  
Transvaginal ultrasonography has been proposed as a reliable method of assessing dimensions of the cervix. The purpose of the current investigation was to establish normative data for cervical width and length during pregnancy. This information may be helpful in predicting patients at risk for preterm birth. A transvaginal 5 or 7.5 MHz transducer was used on 132 consecutive low-risk pregnant women undergoing evaluation for gestational dating purposes. Even in cases of patient obesity or an empty bladder, high resolution was possible and permitted cervical measurement in all but one case. The external cervical width at the vaginal fornices was found to increase with advancing gestation (R = 0.512, P < 0.005). The cervical length from internal os to external os was found not to change with advancing gestation (R = 0.11, P = 0.30). Using these normative data, investigation is recommended to determine whether measuring cervical width and length is useful in predicting preterm labor and delivery.  相似文献   
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A retrospective analysis was conducted to determine the effects of metformin on glycosylated hemoglobin (HbA1c), body weight, and adverse events in an African-American population. Thirty-six patients who were receiving combination therapy with metformin and either a sulfonylurea or insulin were identified from a hospital pharmacy database. Nineteen patients met the criteria for efficacy analysis. The combination of metformin with either a sulfonylurea or insulin resulted in a decrease of the average HbA1c from a baseline of 10.07% to 7.92% (delta = 2.15%). The effect of combination therapy on weight was variable; however, twice as many patients lost weight compared with those who gained weight. Metformin appeared to be well-tolerated, with gastrointestinal symptoms being the most commonly reported adverse events.  相似文献   
69.
Implants of defatted, freeze-dried Saos-2 human osteosarcoma cells grown to confluency induce de novo bone formation in athymic mice. These cells are also richly endowed with bone morphogenetic proteins and express mRNA for bone morphogenetic proteins 1, 2, 3, 4, and 6, as well as for transforming growth factor-β1. Our aim was to study whether the ability to induce bone formation is related to the level of expression of bone morphogenetic protein. We studied the osteoinductive abilities and levels of expression of bone morphogenetic protein of Saos-2 cells both during the growth phase and after confluency was reached. Subconfluent cells were at least 70% less effective in their osteoinductive ability than confluent cells. Comparison of bone morphogenetic protein mRNA expression in confluent and subconfluent cells revealed that the latter had lower expression of all the mRNAs studied. The expression of bone morphogenetic protein-1, bone morphogenetic protein-2, and bone morphogenetic protein-6 mRNAs was 2, 3, and 6 to 10-fold lower, respectively, in subconfluent cells. These results suggest that the ability of Saos-2 cells to induce de novo bone formation may be correlated with the relative expression of these proteins; the expression of bone morpho-genetic proteins in Saos-2 cells also may be dependent on the cell cycle.  相似文献   
70.
The authors have developed and patented a neurosurgical retractor system incorporating an infrared emitter and detector that allows detection of cerebral pulsations. Gentle contact with the surface of cat brains shows cerebral pulsations that correlate with arterial pulse as well as mechanical ventilation. The amplitude of cerebral pulsations decreases with higher retraction pressure and disappears at approximately 20 mmHg. The pressure on the surface of the brain decreased 50% in 5 minutes even though the position of the retractor was maintained constant. The authors postulate that monitoring cerebral pulsation may prove useful in clinical neurosurgery with respect to avoiding excessive retraction, which causes brain damage.  相似文献   
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