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BACKGROUND: The present study investigated whether a failure of self-monitoring contributes to core syndromes of schizophrenia. METHOD: Three groups of patients with a DSM-IV diagnosis of schizophrenia (n = 27), with either prominent paranoid hallucinatory or disorganization syndrome, or without these symptoms, and a matched healthy control group (n = 23) drew circles on a writing pad connected to a PC monitor. Subjects were instructed to continuously monitor the relationship between their hand movements and their visual consequences. They were asked to detect gain changes in the mapping. Self-monitoring ability and the ability to automatically correct movements were assessed. RESULTS: Patients with either paranoid-hallucinatory syndrome or formal thought disorder were selectively impaired in their ability to detect a mismatch between a self-generated movement and its consequences, but not impaired in their ability to automatically compensate for the gain change. CONCLUSIONS: These results support the claim that a failure of self-monitoring may underlie the core symptoms of schizophrenia. 相似文献
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Marked interindividual variability in the response to selective inhibitors of cyclooxygenase-2 总被引:3,自引:0,他引:3
Fries S Grosser T Price TS Lawson JA Kapoor S DeMarco S Pletcher MT Wiltshire T FitzGerald GA 《Gastroenterology》2006,130(1):55-64
BACKGROUND & AIMS: Variability in response to drugs may influence both efficacy and safety. Cyclooxygenase (COX)-2 inhibitors pose a cardiovascular risk by potentially increasing the likelihood of thrombosis, hypertension, and atherogenesis. Differences between individuals in the response to COX-2 inhibitors would be expected to influence their susceptibility to cardiovascular complications. We examined the variability in degree and selectivity of COX-2 inhibition in humans in response to celecoxib and rofecoxib. METHODS: Fifty healthy volunteers received placebo, rofecoxib (25 mg), and celecoxib (200 mg), randomized by order. COX-1 and COX-2 inhibition was determined using ex vivo and in vivo indices of enzymatic activity. A subset of 5 individuals underwent 5 replicate studies to estimate variability in drug response both within and between subjects. RESULTS: Despite the higher COX-2 selectivity of rofecoxib in vitro, the average selectivity attained by 25 mg rofecoxib and 200 mg celecoxib in vivo were not different. However, there was considerable variability at an individual level in the degree of COX-2 inhibition and selectivity attained by both drugs. Approximately one third of the variability was attributable to differences between individuals, suggesting the contribution of genetic sources of variance, such as candidate polymorphisms detected in COX-1 and CYP2C9. CONCLUSIONS: The actual degree of selectivity for inhibition of COX-2 achieved by the coxibs relates both to chemical properties of the drug and to factors within an individual that modulate drug response. These sources of variability might be exploited to identify patients uniquely susceptible to benefit or at developing risk of cardiovascular complications. 相似文献
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de Abreu MG Geiger S Winkler T Ragaller M Pfeiffer T Leutheuser D Albrecht DM 《Intensive care medicine》2002,28(3):318-323
OBJECTIVES: To evaluate the performance of a new device for noninvasive measurement of nonshunted pulmonary capillary blood flow (PCBF) by partial CO2 rebreathing. DESIGN AND SETTING: Prospective clinical trial in an intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: Twenty mechanically ventilated patients with acute lung injury. INTERVENTIONS: Variations in PEEP of +/-3 cmH2O. MEASUREMENTS AND RESULTS: Initially PCBF was measured invasively as cardiac output minus venous admixture (Q(VA)/Q(t)) flow, and by partial CO2 rebreathing at baseline PEEP (PEEP(b)). The PEEP was then reduced by 3 cmH2O (to PEEP(b-3)) and measurements were repeated after 30 min. PEEP was then increased by 6 cmH2O (to PEEP(b+3)), and measurements were repeated after 10, 20, and 30 min. The overall correlation coefficient between noninvasive and invasive PCBF measurements at PEEP(b) was high ( r=0.97), with close agreement between methods being observed (0.1+/-0.6 l/min, bias and precision, respectively). Accordingly, both the correlation coefficient and agreement between methods for changes in PCBF from PEEP(b-3) to PEEP(b+3) levels were satisfactory ( r=0.71; 0.2+/-0.5 l/min, bias and precision). The new device was able to detect the correct PCBF trend in 17 of 20 patients investigated and in all patients who showed invasive PCBF changes equal to or greater than 0.3 l/min ( n=12). Noninvasive PCBF changes were stable as early as 10 min after variation in PEEP, as compared to 30 min values. CONCLUSIONS: The new device appears to be clinically useful for the monitoring of PCBF in patients suffering from acute lung injury. Our results suggest that titration of PEEP aimed at improving PCBF can be performed with the new device. 相似文献
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Wenzel Jan-Per Petersen Elina Nikorowitsch Julius Müller Jessica Kölbel Tilo Reichenspurner Hermann Blankenberg Stefan Girdauskas Evaldas 《The international journal of cardiovascular imaging》2021,37(12):3439-3449
The International Journal of Cardiovascular Imaging - To evaluate the prevalence of aortic regurgitation (AR) and associations between the individual aortic root components and AR severity in the... 相似文献
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Tomy dos Santos Rolo Alexey Ershov Thomas van de Kamp Tilo Baumbach 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(11):3921-3926
Scientific cinematography using ultrafast optical imaging is a common tool to study motion. In opaque organisms or structures, X-ray radiography captures sequences of 2D projections to visualize morphological dynamics, but for many applications full four-dimensional (4D) spatiotemporal information is highly desirable. We introduce in vivo X-ray cine-tomography as a 4D imaging technique developed to study real-time dynamics in small living organisms with micrometer spatial resolution and subsecond time resolution. The method enables insights into the physiology of small animals by tracking the 4D morphological dynamics of minute anatomical features as demonstrated in this work by the analysis of fast-moving screw-and-nut–type weevil hip joints. The presented method can be applied to a broad range of biological specimens and biotechnological processes.The best method to study morphological changes of anatomic features and physiological processes is to observe their dynamics in 4D, that is, in real time and in 3D space. To achieve this we have developed in vivo X-ray cine-tomography to gain access to morphological dynamics with unrivaled 4D spatiotemporal resolution. This opens the way to a wide range of hitherto inaccessible, systematic investigations of small animals and biological internal processes such as breathing, circulation, digestion (1), reproduction, and locomotion (2).At the micrometer resolution range, state-of-the-art optical imaging techniques can achieve high magnifications to visualize tissues and even individual cells for 4D studies. These methods however are confined to transparent or fluorescent objects, or are limited either by low penetration depth <1 mm or poor time resolution (3). For optically opaque living organisms X-ray imaging methods are highly appropriate due to the penetrating ability of the radiation. Modern synchrotron radiation facilities provide brilliant and partially coherent radiation suitable for high-resolution volume imaging methods such as X-ray computed microtomography (SR-µCT). For static specimens SR-µCT has proven to be a powerful tool to study small animal morphology in 3D (4–6). The benefits of various physical contrast mechanisms, high spatial resolution, and short measuring times, as well as enormous sample throughput compared with laboratory X-ray setups, have led to its widespread use in life sciences.Real-time in vivo X-ray imaging with micrometer spatial resolution was realized so far by recording time sequences of 2D projection radiographs of different organisms (1, 6, 7), providing time information about functional dynamics but losing any information about the third spatial dimension.Recently, 4D in vivo X-ray experiments have been performed to study cell migration in frog embryos (8, 9) using tomographic sequences of a few seconds exposure time per tomogram interrupted by longer nonexposure time slots. In this way the authors followed relatively slow dynamics and morphological changes during embryonic development with 2-µm resolution over total time intervals of several hours. The fastest 4D time series yet reported were realized with a temporal resolution of 0.5 s and spatial resolution of 25 µm (10), applied to a living caterpillar used as test specimen for imaging, but without any analysis of dynamics.In this paper, we demonstrate the quantitative 4D investigation of morphological dynamics by in vivo X-ray 4D cine-tomography, introduced here as the combination of ultrafast SR-µCT and motion analysis procedures. Using this approach allows us to investigate previously inaccessible 3D morphological dynamics in small animals, presently with feature sizes in the micrometer range and with temporal resolution down to a few tens of milliseconds. In the past, ultrafast in vivo imaging was hardly possible for such applications, due to the strongly competing requirements for simultaneous high contrast, high signal-to-noise ratio (SNR), and concurrent low radiation dose, as well as the need for simultaneous high spatial resolution and maximum temporal resolution.In the following we describe how in vivo X-ray 4D cine-tomography meets the above challenges by optimizing image contrast, SNR, and spatial and temporal resolution in the ultrafast SR-µCT system and by establishing a dedicated data analysis pipeline, all within a unified framework (Fig. S1). We demonstrate the potential of the technique by investigating morphological dynamics in fast-moving weevils, focusing here on the exoskeletal joints. 相似文献