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OBJECTIVE: This study characterized objectively the hypersomnia frequently seen in the depressed phase of bipolar affective disorder. On the basis of previous work in sleep and affective disorders, it has been hypothesized that the hypersomnia is related to greater REM sleep. This hypothesis was tested by using a multiple sleep latency test to compare bipolar affective disorder with narcolepsy, a well-defined primary sleep disorder associated with known REM sleep dysfunction. METHOD: Twenty-five bipolar depressed patients were selected on the basis of complaints of hypersomnia. They underwent 2 nights of polysomnography followed by a multiple sleep latency test. Data on their nocturnal sleep and daytime naps were compared with similar data on 23 nondepressed narcoleptic patients referred for sleep evaluation. RESULTS: Despite their complaints of hypersomnia, no abnormalities were noted for the bipolar group in the results from the multiple sleep latency test. Contrary to the working hypothesis, REM sleep was notably absent during daytime naps in the depressed patients, in marked contrast to the findings for the narcoleptic group. CONCLUSIONS: The complaint of sleepiness in the hypersomnic bipolar depressed patient appears to be related to the lack of interest, withdrawal, decreased energy, or psychomotor retardation inherent in the anergic depressed condition, rather than an increase in true sleep propensity or REM sleep propensity.  相似文献   
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Taq polymerase contains bacterial DNA of unknown origin   总被引:9,自引:0,他引:9  
The polymerase chain reaction (PCR) was carried out with the highly conserved E. coli ribosomal RNA gene sequences 1376-1395 and 1521-1540. Using these primers and reaction conditions specified by the manufacturer(s), a 165 bp fragment was synthesized using Taq polymerase from three different sources in the absence of any added template. Restriction enzyme analysis suggests the source of this bacterial DNA is neither E. coli nor Thermus aquaticus. A variety of different methods to eliminate it such as treatment with DNase, restriction enzyme digestion, and CsCl2 density gradient centrifugation were unsuccessful. Since the bacteria in which the Taq polymerase is produced are not the source of the DNA, some step(s) in the purification or reagents added to the enzyme must be involved. Thus it is likely other biological products are similarly contaminated. Although the problem is easily dealt with by running a no-template control and choosing other primers if a problem exists, it is important to recognize the potential for a false-positive result.  相似文献   
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Previous studies have demonstrated variation in vascular events with respect to season and time of day. Changes in barometric pressure display daily and seasonal variations and could modulate the occurrence of vascular events. The objective of this study was to determine whether a relation exists between changes in barometric pressure and occurrence of stroke or acute myocardial infarction (AMI). A retrospective analysis of hospital admissions for AMI and stroke from 1993 to 1996 in central Texas was related to changes in atmospheric pressure that were obtained from the National Climatic Data Center. Patients who had AMI (n = 1,327) or stroke (n = 839) were identified from a computerized hospital database. Mean atmospheric pressure, greatest change in pressure, and rate of change in pressure per 24-hour period were computed. One-, 2-, and 3-day and seasonal groupings of cardiovascular events were related to corresponding changes in barometric pressure. The fall and winter seasons had the highest variability in atmospheric pressure readings. There was a significant correlation (p = 0.0083) between a decrease in atmospheric pressure and the occurrence of AMI the day after a pressure decrease, especially during the fall and winter seasons. No relation between stroke and atmospheric pressure was demonstrated. In conclusion, we conclude that rapid decreases in barometric pressure are associated with the occurrence of AMI but not of stroke.  相似文献   
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Because there is no consensus regarding the precise distribution of induced endothelial tissue factor (TF), we studied TF activity in and on tumor necrosis factor alpha-stimulated cultured human umbilical vein endothelial cells (ECs) and their underlying matrix. TF was mainly expressed on the cell surface. Only small traces were found on the apical surface suggesting that TF is predominantly located on the basolateral side of the cell membrane. The presence of TF on the cell surface was confirmed by flow cytometry. Subendothelial TF activity appeared to be dependent upon the procedure used to remove the stimulated EC monolayer. Whereas ammonium hydroxide or hypotonic lysis resulted in relatively high levels of matrix-associated TF, virtually no TF was found on the matrix after mild enzymatic detachment of stimulated ECs. Cell removal with EDTA resulted in intermediate levels of matrix-associated TF. Neither the enzymatic treatment nor EDTA degraded or removed this TF activity. Similar patterns were observed for matrix-associated TF antigen and EC surface markers. Electron microscopic analysis showed cell fragments on the matrix after monolayer lysis. The findings strongly suggest that induced endothelial TF associated with the subendothelial matrix actually represents TF on EC remnants.  相似文献   
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Sephacryl beads containing an immobilized aminopropylcobalamin- transcobalamin-II complex serve as foci for the adherence of L1210 murine leukemia cells. Bead-cell interaction does not occur when (A) nonderivatized beads are used; (B) transcobalamin-II is omitted or presaturated with cyanocobalamin in the preparation of the bead complex; (C) intrinsic factor replaces transcobalamin-II; and (D) the complex is removed from beads by photolysis. These observations suggest that adherence results from the ability of transcobalamin-II to form a bridge between immobilized cobalamin on the bead and receptors in the plasma membrane of the cell.  相似文献   
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Background: Although interpersonal psychotherapy (IPT) is an efficacious treatment for acute depression, the relative efficacy of treatment in each of the four IPT problem areas (grief, role transitions, role disputes, interpersonal deficits) has received little attention. We evaluated the specificity of IPT by comparing treatment success among patients whose psychotherapy focused on each problem area. Moreover, we sought to understand how the patient characteristics and interpersonal problems most closely linked to the onset of a patient's current depression contributed to IPT success. Methods: Patients meeting DSM‐IV criteria for an episode of major depressive disorder ( n =182) were treated with weekly IPT. Remission was defined as an average Hamilton Rating Scale for Depression 17‐item score of 7 or below over 3 weeks. Personality disorders were diagnosed using the Structured Clinical Interview for DSM‐IV Personality Disorders. Results: Contrary to our prediction that patients whose treatment was focused on interpersonal deficits would take longer to remit, survival analyses indicated that patients receiving treatment focused on each of the four problem areas did not differ in their times to remission. Nor were patients in the interpersonal deficits group more likely to have an Axis II diagnosis. Patients whose treatment focused on role transitions remitted faster than those whose treatment focused on role disputes, after controlling for covariates. Conclusion: With skillful use of IPT strategies and tactics and with careful medication management where appropriate, patients in this study whose treatment focused on each problem area were treated with equal success by trained IPT clinicians. Depression and Anxiety, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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