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951.
BACKGROUND: Choosing the optimum pancreatic enzyme replacement therapy for patients with exocrine insufficiency remains a problem. An enteric coated enzyme microsphere pancreatic enzyme preparation (Pancrease) has been marketed with several levels of lipase activity, implying that there is a dose-response relationship between dose and effectiveness such that the high potency form appears to be the most cost effective. METHODS: In a randomized, single-blind, cross-over study, we evaluated the effectiveness of a commercial enzyme preparation with different amounts of lipase per dosage unit in adults with exocrine pancreatic insufficiency. Patients received a diet comprising 100 g fat each day for 6 days. With each meal (three per day) they received two capsules of either Pancrease MT4 (8000 unit lipase), Pancrease MT10 (20,000 units lipase), Pancrease MT16 (32,000 units lipase) or placebo. A 72-h quantitative faecal collection was carried out for the last 3 days of the 6-day period. RESULTS: There was a reduction in faecal fat excretion with each of the preparations compared to placebo. The difference failed to reach significance with the 8000 units lipase preparation (P > 0.05) but was significant (P = 0.02) with the 20,000 units lipase and the 32,000 units lipase preparations (faecal fat excretion: placebo = 42.1 +/- 29 g, lipase 8000 = 22.1 +/- 7.3 g, lipase 20,000 = 10.2 +/- 4.5 g and lipase 32,000 = 15.8 +/- 12.5 g, P < for 20,000 units and 32,000 units lipase compared to placebo). CONCLUSION: A dose-response relationship between the amount of lipase administered with each meal and a reduction in faecal fat was not evident. The most potent preparation did not provide additional benefits compared to the less expensive lower potency dosage form. 相似文献
952.
We have studied the impact of various kinds of abuse and neglect on the child's perception of himself and his future. We found, when considering physical abuse, physical neglect, verbal abuse, emotional neglect, and sexual abuse, that less than 5% of these mistreatments occurred in isolation. Since the vast majority of mistreated children are subject to more than one kind of abuse or neglect, it was important to delineate which combinations have the greatest effect. We found that a combination of physical neglect, physical abuse, and verbal abuse had the greatest impact on children, affecting such things as their enjoyment of living and hopes for the future. An early age of onset for verbal abuse and emotional neglect was significantly associated with greater severity and frequency of mistreatment. Neglect appears to be a precursor to abuse in many cases. 相似文献
953.
I Hansen AR Jensen NA Peterslund PL Andersen 《Canadian Metallurgical Quarterly》1998,160(22):3227-3230
A case of Mb. Castleman of the localized plasma cell type is reported. This disease expresses several symptoms from different organ systems and therefore an extensive investigation program is often performed. Diagnosis is possible through consideration of all clinical components at the same time: Refractory anaemia, high and refractory SR, weight loss, B-symptoms, but at the same time a relatively good health. CT-scan-demonstration of a localized tumour is an important clue. Histopathologically, the tumour shows vascular hyperproliferation and plasmacytosis of varying maturation. Immunophenotyping of the plasma cells and immunoblasts usually reveals a polyclonal population. Needle biopsies from several regions may be necessary to detect the polyclonality, because monoclonality is often widespread locally in the tumour. HHV8 is correlated to the multicentric PC-type of Mb. Castleman. However, no HHV8 was found in this case. 相似文献
954.
A simple, low cost, easy to use computer-based Digital Image system has been developed for characterizing defects which occur in various types of organic films. The system uses an optical microscope, high resolution TV camera, frame grabber to display the image on Macintosh computer and software to analyze and characterize the image. All components are commercially available. Using this system, many different defects which are typically seen in organic coatings and the support on to which they are coated, such as spots, bubbles, reticulation streaks and pinholes can be rapidly characterized. Quantitative information about the defect, such as size and frequency can be rapidly obtained to assist in determining the cause. Images obtained of the defects can also be enhanced to obtain characterization information not easily seen in the defect. The system has applications in the R and D laboratory for understanding defect mechanisms, in trouble-shooting plant and end-use problems and in the control laboratory. It can also be used to provide routine quantitative testing information on defects that have been typically evaluated by subjective tests and comparison with go/no-go standards. The system is easier to use than viewing with a glass or conventional microscope and a permanent record of the defects can easily be stored and retrieved in a computer database to assist in troubleshooting. 相似文献
955.
I-Hsing Tan Dudley J.J. Babic D.I. Cohen D.A. Young B.D. Hu E.L. Bowers J.E. Miller B.I. Koren U. Young M.G. 《Photonics Technology Letters, IEEE》1994,6(7):811-813
We demonstrate greater than 90% quantum efficiency in an In0.53Ga0.47As photodetector with a thin (900 Å) absorbing layer. This was achieved by inserting the In0.53 Ga0.47As/InP epitaxial layer into a microcavity composed of a GaAs/AlAs quarter-wavelength stack (QWS) and a Si/SiO2 dielectric mirror. The 900-Å-thick In0.53 Ga0.47As layer was wafer fused to a GaAs/AlAs mirror, having nearly 100% power reflectivity. A Si/SiO2 dielectric mirror was subsequently deposited onto the wafer-fused photodiode to form an asymmetric Fabry-Perot cavity. The external quantum efficiency and absorption bandwidth for the wafer-fused RCE photodiodes were measured to be 94±3% and 14 nm, respectively. To our knowledge, these wafer-fused RCE photodetectors have the highest external quantum efficiency and narrowest absorption bandwidth ever reported on the long-wavelength resonant-cavity-enhanced photodetectors 相似文献
956.
Previous work has demonstrated that group-delay spectra in single-mode fibers can be measured with 0.1-ps resolution by a white-light cross-correlation technique. An application would be to pretest short fibers before drawing an entire preform. This could be particularly useful for achieving high draw yield for fibers whose dispersion spectra are sensitive to core diameter. This paper describes measurements of minimum-dispersion spectra that were obtained using 4-m lengths of fiber that were cut from each end of kilometer-long quadruple-clad, triangular-index, and step-index depressed-clad fibers. The axial uniformity of fiber dispersion was found to be very good. Results show that averaging dispersion spectra using short fiber segments from each end produces excellent agreement when compared with the dispersion spectrum determined from conventional pulse-delay measurements on a long length of fiber. 相似文献
957.
958.
Advances for achieving user control of a dynamic simulation of linked figures is presented. The formulation integrates forward and inverse kinematics specification within a mixed method of forward and inverse dynamics simulation. Kinematic specifications can be imposed through kinematic constraints embedded within the dynamics framework. Kinematic constraints may be simple (functions of one degree of freedom), or complex (functions of multiple interrelated degrees of freedom). Thus, keyframed paths, closed loops, point-to-path constraints, and collisions between links and the environment can be simulated. A simultaneous solution for unknown motion and forces of constraint is performed. A Lagrange multiplier method is outlined for incorporating these general constraints into the mathematical formulation of the equations of motion. Results from three example simulations are presented and discussed. 相似文献
959.
K. A. Taylor G. B. Olson M. Cohen J. B. Vander Sande 《Metallurgical and Materials Transactions A》1989,20(12):2749-2765
Microstructural changes which accompany the first stage of tempering have been studied by transmission electron microscopy
(TEM) and electrical resistometry in two Fe-Ni-C alloys that form platelike martensite. The ε-carbide transition phase in
these alloys adopts a platelike shape with a habit plane near {012=α. Electron diffraction data indicate that the carbide may be partially ordered, resulting in orthorhombic symmetry, and therefore,
this phase is designated as ε′- carbide. The carbide particles contain a fine internal substructure which appears to represent an internal accommodation
deformation (faulting) on the carbide basal plane. Detailed analysis of the kinematics of carbide precipitation suggests that
the observed habit plane and accommodation deformation permit an invariant-plane strain transformation which minimizes elastic
strain energy. The apparent selection of only a limited number of possible orientation variants is explained in terms of the
symmetry of the parent martensitic phase, which is known to undergo spinodal decomposition prior to the nucleation of the
transition carbide. The martensitic substructure is not found to exert any significant influence on this overall precipitation
behavior.
formerly with the Massachusetts Institute of Technology
formerly with the Massachusetts Institute of Technology 相似文献
960.