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1.
For patients with Alzheimer's disease (AD), a recommendation to stop operating a motor vehicle can be a serious event complicated by a loss of self-esteem and personal dignity. Patients are often reluctant to give up an activity so essential, both practically and symbolically, to independent living. We describe here a patient with moderately progressed AD who lacked insight of his need to cease driving. Through an integrative treatment approach, combining behavioral and psychodynamic modalities, we helped him to formulate effective ways of coping with his loss of access to independent transportation. We favor a psychotherapeutic strategy that combines behavioral and managerial measures with dynamic patient interaction, thereby developing the patient's insight of the need to give up driving while fostering his sense of autonomy.  相似文献   
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Thyrotropin releasing hormone (TRH) was administered intravenously to ten patients with Alzheimer's Disease (AD) in a high-dose paradigm, thought to maximize central nervous system effects and potentially produce facilitation of cholinergic function, a known property of the neuropeptide. Acute effects of TRH on behavioral, cognitive and physiologic measures were assessed after patients received 0.1 mg/kg TRH, 0.3 mg/kg TRH and placebo, the higher TRH dose and placebo being given in a randomized, double-blind fashion. Patients showed statistically significant increases in arousal and improvement in affect, as well as a modest improvement in semantic memory, all after receiving the higher TRH dose. Both TRH doses produced transient rises in systolic blood pressure, with no effect on diastolic blood pressure, heart rate or temperature. This study suggests that high-dose TRH can be safely administered to AD patients and is neurobehaviorally active; further studies are needed to determine the extent and mechanism of the cognitive and psychobiological properties of this peptide in AD and other neuropsychiatric disorders.  相似文献   
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BACKGROUND: Earliest recorded postshock myocardial activations in pigs originate in the subepicardium of the apex and lateral free wall of the left ventricle (LV) 30-90 ms after the shock. OBJECTIVE: The purpose of this study was to determine whether the Purkinje system is a candidate for the source of postshock activations by performing endocardial and transmural postshock activation mapping. METHODS: In five pigs, 32 plunge needles with 12 electrodes (1-mm spacing) were inserted into the LV apex and lateral free wall. Up to 70 plunge needles with six electrodes (2-mm spacing) were spread throughout the remainder of the LV, while 9-12 plunge needles with four electrodes (2-mm spacing) were inserted into the right ventricle. A basket catheter with 32 bipolar recording sites was inserted into the LV. Defibrillation-threshold (DFT)-level shocks were delivered during 10 episodes of electrically induced ventricular fibrillation. Electrograms of postshock activation cycles were analyzed for Purkinje and myocardial activations. RESULTS: Purkinje activations were recorded before local myocardial activation in 9% of basket electrograms and in 15% of plunge needles during the first postshock activation cycle. Purkinje activations were identified during the first and subsequent several postshock activation cycles in at least one basket and one needle electrogram in 96% and 98% of defibrillation episodes, respectively. CONCLUSIONS: The Purkinje system is active during the early postshock activation cycles after DFT-level shocks. Further studies are required to determine whether activation initiates in the Purkinje system or whether it is activated by the myocardium or by Purkinje-myocardial junctional cells.  相似文献   
5.
We have developed a method for quantifying the complexity of activation patterns observed during ventricular fibrillation (VF) that is based on our previously reported methodology for decomposing epicardial mapping data into a set of isolated wavefronts. One-half second datasets are acquired from a 21×24 array of unipolar electrodes (1 mm spacing), and the wavefronts are isolated. A correlation technique is used to compute the similarity between all possible pairs of the isolated wavefronts. From these data, the wavefronts are sorted into clusters, each of which represents a recurring wavefront morphology. We define multiplicity (M) as the number of clusters needed to account for 90% of the total activations in the VF episode.M measures the complexity of the rhythm. In repetitive patterns (e.g., sinus rhythm),M=1, indicating that the same morphology repeatedly activates the mapped region. Typically, in VF,M>1, with larger numbers representing more complex, disorganized patterns. As an example, we computedM at 5, 10, 15, and 20 sec after electrical induction of VF in six pigs.M decreased significantly (p<0.001), suggesting increasing organization during this period.  相似文献   
6.
Mining SNPs from EST databases   总被引:27,自引:5,他引:27  
There is considerable interest in the discovery and characterization of single nucleotide polymorphisms (SNPs) to enable the analysis of the potential relationships between human genotype and phenotype. Here we present a strategy that permits the rapid discovery of SNPs from publicly available expressed sequence tag (EST) databases. From a set of ESTs derived from 19 different cDNA libraries, we assembled 300,000 distinct sequences and identified 850 mismatches from contiguous EST data sets (candidate SNP sites), without de novo sequencing. Through a polymerase-mediated, single-base, primer extension technique, Genetic Bit Analysis (GBA), we confirmed the presence of a subset of these candidate SNP sites and have estimated the allele frequencies in three human populations with different ethnic origins. Altogether, our approach provides a basis for rapid and efficient regional and genome-wide SNP discovery using data assembled from sequences from different libraries of cDNAs.  相似文献   
7.
Archives of Sexual Behavior - One- to two-thirds of new HIV infections among sexual minority men occur within the context of main partnerships. This has led to increasing attention to the rules and...  相似文献   
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With growing evidence of long-term neurological damage in individuals enduring repetitive head trauma, it is critical to detect lower-level damage accumulation for the early diagnosis of injury in at-risk populations. Proton magnetic resonance spectroscopic scans of the dorsolateral prefrontal cortex and primary motor cortex were collected from high school American (gridiron) football athletes, prior to and during their competition seasons. Although no concussions were diagnosed, significant metabolic deviations from baseline and non-collision sport controls were revealed. Overall the findings indicate underlying biochemical changes, consequential to repetitive hits, which have previously gone unnoticed due to a lack of traditional neurological symptoms.  相似文献   
10.
In this text, we present and elaborate ethical challenges in transplant medicine related to organ procurement and organ distribution, together with measures to solve such challenges. Based on internationally acknowledged ethical standards, we looked at cases of organ procurement and distribution practices that deviated from such ethical standards. One form of organ procurement is known as commercial organ trafficking, while in China the organ procurement is mostly based on executing prisoners, including killing of detained Falun Gong practitioners for their organs. Efforts from within the medical community as well as from governments have contributed to provide solutions to uphold ethical standards in medicine. The medical profession has the responsibility to actively promote ethical guidelines in medicine to prevent a decay of ethical standards and to ensure best medical practices.  相似文献   
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