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1.
Die anthroposophische Misteltherapie kann etablierte onkologische Standardtherapien im Sinne einer umfassenderen und ganzheitlichen Versorgung erg?nzen.  相似文献   
2.
Observations made in an investigation of the diurnal variation of the serum iron concentration suggested that the diurnal variations of serum iron can be explained as a phenomenon secondary to the diurnal variation of the hemoglobin metabolism. This hypothesis is supported by parallel changes in the bilirubin and serum iron values.  相似文献   
3.
Purpose. The study was designed to determine trabecular meshwork (TM) stiffness and its relationship to outflow facility (C) in perfused normal human and porcine eyes. Methods. Human and porcine eyes were perfused at pressures of 10, 20, 30, and 40 mm Hg to determine C and how outflow resistance (R = 1/C) varied with the pressure. Following perfusions, TM tissue segments were dissected and stretched uniaxially to determine the circumferential bulk Young's modulus (E). The statistical significance of difference between different groups was evaluated using a two-tailed Student's t-test or Mann-Whitney U test. Results. A larger E correlated with a higher C measured at 10 and 20 mm Hg (P < 0.05), and a similar trend was observed at 30 and 40 mm Hg in human eyes (n = 7). Additionally, a higher C correlated to a lower variance of R, and a stiffer TM correlated to a lower variance of R in human eyes (P < 0.05). For porcine TM, E was inversely correlated to a cross-sectional area (P < 0.003, n = 11), and its value (24.9 and 1.5 kPa; geometric mean and geometric SE) was lower than E of human TM (515 ± 136 kPa; mean ± SE) (P < 0.01). C and variance of R were not significantly different between the species. Conclusions. A higher circumferential stiffness of the TM correlated with a higher outflow facility and less IOP elevation-induced variation in outflow resistance in normal human eyes, but not in porcine eyes. For future studies, these correlations need to be evaluated in glaucomatous eyes to better understand normal and abnormal TM functions.  相似文献   
4.
Purpose. An intracanalicular scaffold (Hydrus microstent) designed to reduce intraocular pressure as a glaucoma treatment was tested in human anterior segments to determine changes in outflow facility (C). Methods. Human eyes with no history of ocular disease or surgeries were perfused within 49 hours of death. The anterior segments were isolated and connected to a perfusion system. Flow rates were measured at pressures of 10, 20, 30, and 40 mm Hg. The scaffold was inserted into Schlemm's canal of the experimental eye, while a control eye underwent a sham procedure. Flow rate measurements were repeated at the four pressure levels. Individual C values were computed by dividing the flow rate by its corresponding pressure, and by averaging the four individual C measurements. The change in C between control and experimental eyes was assessed by the ratio of the baseline and second C measurement. In two eyes, the placement of the scaffold was evaluated histologically. Results. After scaffold implantation in the experimental eyes, the average C increased significantly from baseline (n = 9, P < 0.05). Ratios of C at all pressure levels, except for 10 mm Hg, were significantly higher in experimental eyes (n = 9) than control eyes (P < 0.05, n = 7). Histologically, the scaffold dilated Schlemm's canal with no visible damage to the trabecular meshwork. Conclusions. The Hydrus Microstent provided an effective way to increase outflow facility in human eyes ex vivo.  相似文献   
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6.
Anthropomorphic radiologic phantoms   总被引:1,自引:0,他引:1  
A technique is being developed for the design and fabrication of anthropomorphic phantoms for diagnostic x-ray imaging. Anatomic information extracted from actual patient radiographs is incorporated into the phantoms using computer image processing and computer-assisted machining methods. In this paper, the technique is described as applied to a breast phantom, and preliminary images that closely mimic human anatomy on radiographs are shown.  相似文献   
7.
8.
Central thrombi in pulmonary arterial hypertension detected by MR imaging   总被引:1,自引:0,他引:1  
Fisher  MR; Higgins  CB 《Radiology》1986,158(1):223-226
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.  相似文献   
9.
After obtaining baseline intraocular pressure (IOP) measurements for 1 week, prostaglandin (PG) F2 alpha (250 micrograms in 50 microliters saline) or epinephrine 2% solution (50 microliters) was topically applied twice daily for 2 weeks to one eye of six cynomolgus monkeys for each agent tested. Contralateral control eyes received their respective vehicles. PGF2 alpha significantly reduced IOP beginning 2 to 3 hr after the first dose, persisting thereafter. A significant (P less than 0.05) hypotensive effect remained for at least 10 hr after the first dose and at least 14 hr after the sixth dose. At 4 hr after the seventh dose, the mean reduction was 10.2 +/- 3.5 (+/- SD) mmHg below baseline (P less than 0.0025). At this time, there was also a significant (P less than 0.01) mean reduction of IOP in the contralateral vehicle-treated eyes of 6.0 +/- 3.3 (+/- SD) mmHg below baseline, which did not appear to be secondary to diurnal fluctuations, repeated tonometry, experimental manipulation, or inadvertent drug transfer. Epinephrine significantly (P less than 0.05) reduced IOP beginning 3 hr after the first dose, but this reduction was minimal and not consistent. Neither PGF2 alpha nor epinephrine altered aqueous flow as measured by fluorophotometry 2 to 6 hr after the fifth dose. Outflow facility could not be assessed by indentation tonography because IOP was often too low at the time of measurement. Whereas PGF2 alpha did not alter pupil size, epinephrine caused significant pupillary dilation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Atrial-level shunts: sensitivity and specificity of MR in diagnosis   总被引:4,自引:0,他引:4  
  相似文献   
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