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101.
Delineating the sites and progression of in vivo atrophy in multiple system atrophy using fluid-registered MRI. 总被引:1,自引:0,他引:1
Jonathan M Schott Jessica E Simon Nick C Fox Andrew P King M Nadeem Khan Lisa Cipolotti Dominic C Paviour John M Stevens Martin N Rossor 《Movement disorders》2003,18(8):955-958
We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA. 相似文献
102.
Jeffrey T Cope MD Michael C Mauney MD David Banks BS Oliver A.R Binns MD Christopher L Moore BS Jeffrey J Rentz BS Kimberly S Shockey MS R.Christoper King MD Irving L Kron MD Curtis G Tribble MD 《The Annals of thoracic surgery》1997,63(6)
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non–heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non–heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non–heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.(Ann Thorac Surg 1997;63:1664–8) 相似文献
103.
104.
105.
Howard Weinstein Michael A. King Christopher P. Reinhardt Brenda A. McSherry Jeffrey A. Leppo 《Journal of nuclear cardiology》1994,1(1):39-51
Background
Simultaneous dual-radionuclide technetium 99m/thallium 201 scintigraphy can potentially produce perfectly aligned stress and rest images in less time than conventional protocols. However, interradionuclide crossover limits diagnostic accuracy. Accordingly, we evaluated99mTc and201Tl crossover in line and heart phantoms. 相似文献106.
Evaluative composite measurement scales (CMS) are increasingly used in medicine to measure complex constructs in the absence of a reference criterion or ‘gold standard’. However, the level of measurement provided by these instruments has usually been given little attention. This paper explores the influence of the characteristics of the item set and weighting on the level of measurment of an evaluative CMS. The approach is illustrated with an application to the scoring system of the Nottingham Health Profile. Simulations are provided to indicate when the composite score of item responses, on an ordinal or pass—fail scale, could be considered to achieve the properties of an interval scale. 相似文献
107.
A new radiolucent device for increased accuracy of CT-guided fine-needle punctures permits precise determination of the optimum
angle, depth, and position of the fine needle, which can be preset from the data supplied on the CT monitor. Puncture and
repeat scans for controlling the tip of the needle can be performed with the patient in a stationary position. The device
is designed as a belt that holds a needle holder sheath and a goniometric scale, both of which can be moved to varying positions
around the patient. 相似文献
108.
Rafael E. Cuellar MD Walter H. Kaye MD L. K. George Hsu MD Dr. David H. Van Thiel MD 《Digestive diseases and sciences》1988,33(12):1549-1553
Bulimia nervosa is a health problem of increasing magnitude that is estimated to affect 2–5% of the American adolescent and young adult female population. Because of the magnitude of this clinical problem and because of the importance of the upper gastrointestinal tract in its expression, a intradepartmental program of health care for patients affected with the disease was initiated. Eleven consecutive symptomatic bulimic individuals have been evaluated jointly by the gastroenterology and the psychiatry departments of the University of Pittsburgh. Five of these 11 individuals were found to have clinically important upper gastrointestinal pathology including ulcerative esophagitis, erosive gastritis, duodenal ulcer, and delayed gastric emptying. These gastrointestinal conditions could have been either a result of or have contributed to the symptomatology of these five patients. These data suggest that bulimic subjects have clinically important gastroenterological disease processes that require specific diagnosis and treatment independent of the psychiatric treatment provided for the bulimic condition.This work was supported in part by grants from NIDDK AM 32556. 相似文献
109.
Mari-Ann Flyvholm Barbara M. Hall Tove Agner Eva Tiedemann Peter Greenhill Walter Vanderveken Fred E. Freeberg Torkil Menné 《Contact dermatitis》1997,36(1):26-33
Our purpose was to investigate the eliciting threshold concentration of formaldehyde in formaldehyde-sensitive individuals in the occluded and non-occluded patch teat and to evaluate the relationship in repeated open application test (ROAT) with a product containing a formaldehyde releaser. 20 formaldehyde-sensitive patients and a control group of 20 healthy volunteer were included in the study. Occluded and non-occluded patch tests with formaldehyde solutions form 25 to 10,000 ppm. and ROAT for I week with a leave-on cosmetic product containing on average 300 ppm formaldehyde. Were carried out simultaneously on each subject. In the occluded patch test. 1/2 of the 20 patients only reacted to 10,000 ppm formaldehyde. 9 reacted to 5,000 ppm. 3 reacted to 1.000 ppm. 2 reacted to 500 ppm and I reacted to 25 ppm. No definite positive reactions were observed in the non-occluded patch test or in the ROAT No positive reactions were observed in the control group to any of the test procedures. We concluded that the threshold concentration for occluded patch test to formaldehyde in formaldehyde-sensitive patients was 250 ppm. The threshold in occluded patch test corresponded to the degree of sensitivity Definite positive reactions in the ROAT were not seen, either indicating that they are unlikely to happen with the type of product used or that the exposure time was too short. 相似文献
110.
Munzel Peter; Bock-Hennig Barbara; Schieback Sylvia; Gschaidmeier Harald; Beck-Gschaidmeier Simone; Bock Karl Walter 《Carcinogenesis》1996,17(2):197-202
Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol1012 M TCDD moderately increased EGF-stimulated DNA synthyesis( 相似文献