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31.
LJ Huang FC Chang KH Lee JP Wang CM Teng SC Kuo 《Canadian Metallurgical Quarterly》1998,6(12):2261-2269
2-Amino (6), 2-alkylamino (7-8), 2-methoxy (9), 2-acetamido (10), and 5,8-diacetoxy (11) derivatives of the lead compound 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (4) were synthesized, together with 6,7-dichloro-5,8dimethoxy-1,4-naphthoquinone (5), a positional isomer of 4. Antiplatelet, antiinflammatory, and antiallergic activities were evaluated, and most compounds were quite potent in all assays. Compounds 5 and 9-11 were especially active; however, 5 was ineffective against neutrophil superoxide formation, and 10 was ineffective against mast cell degranulation. 相似文献
32.
Tetralogy of Fallot was diagnosed in an acyanotic 11-month-old dog. Predicted pressure gradient across the pulmonic valve, as assessed by use of continuous wave Doppler echocardiography, was 94.5 mm Hg. Bidirectional shunting was identified by means of selective angiography. Open-heart correction was performed, using a transatrial approach with limited ventriculotomy and cardiopulmonary bypass. The hypertrophied infundibulum was resected, the ventricular septal defect was closed primarily, and a transannular pericardial patch graft was applied. Pressure gradients across the pulmonic valve were 52.9 and 22.8 mm Hg 2 weeks and 4 months after surgery, respectively. Advances in cardiopulmonary bypass, anesthetic management, and use of the transatrial approach may improve the success of open-heart correction of tetralogy of Fallot in dogs. 相似文献
33.
The commercially available spray management valve provided consistent flow rates when used with hand-compression sprayer systems. The 15-psi spray management valve maintained a constant flow rate of 180, 150, and 155 ml/min in combination with a fine 45 degrees flat fan nozzle and Hudson. B&G, and Chapin hand-compression sprayers, respectively. The 30-psi spray management valve maintained a constant flow rate and adequate spray-on time when combined with the coarse flat fan nozzle for each of the 3 hand-compression sprayers tested. 相似文献
34.
Chandalia J.K. Eggleton B.J. Windeler R.S. Kosinski S.G. Liu X. Xu C. 《Photonics Technology Letters, IEEE》2001,13(1):52-54
We study adiabatic mode propagation in tapered air-silica microstructured optical fibers and demonstrate efficient coupling into a robust high-delta microstructured fiber. In the waist region of the taper, the core mode is tightly confined by the air holes and exhibits properties similar to a high-delta waveguide such as enhanced peak intensity and widely flattened anomalous dispersion. We exploit these properties to generate tunable self-frequency shifting Raman solitons over the communications window from 1.3 μm to 1.65 μm, with over 60% conversion efficiency These fiber devices are practical for several reasons: they can be fusion spliced to standard single-mode fibers with relatively low loss, they are mechanically strong, due to the supporting cladding, and because the mode is isolated from the surrounding air interface, they can potentially be recoated allowing for packaging 相似文献
35.
36.
Acoustic reflex thresholds (ART) and loudness discomfort levels (LDL) were obtained from 51 ears of 34 deaf children using broad band noise and pure tones. Both thresholds and levels were recorded using the psychophysical method of tracking. Results indicate that the relationship between ART and LDL is at variance with similar data for normal hearing individuals. Specifically, in over 39% of these deaf children LDL was obtained at a lower intensity than ART. Implications for hearing aid fitting with deaf children are discussed. 相似文献
37.
Cosmetic facial surgery can improve appearance but it cannot make everyone beautiful (or handsome) or solve all problems. The patient must be well motivated and must comprehend the limitations of the procedures. Procedures useful in providing a more youthful appearance include blepharoplasty, browlift and face-lift. Sometimes all three are indicated. Chemical face peeling is used for correction of fine skin lines. 相似文献
38.
CM Rovainen 《Canadian Metallurgical Quarterly》1977,36(10):2386-2389
Tidal breathing of adult lampreys is produced by a single phase of excitation that compresses the branchial basket for exhalation. Inhalation is due to passive recoil. Motoneurons are located primarily in the ipsilateral motor nucleus of the vagus and exhibit periodic bursts of excitatory synaptic potentials from unidentified generator cells in the medulla. Respiratory discharges continue in the isolated brain and can be recorded from the vagal roots. The frequency of bursts increases with temperature in a manner roughly similar to that of intact animals. However, the discharges of the isolated brain are not very sensitive to altered pH or oxygen content in the bathing fluid. Mechanoreceptors in the gill can initiate "cough" responses and may modulate normal breathing. 相似文献
39.
PURPOSE: Looking for a valid, reliable, and feasible method to collect data on the performances of practicing family physicians, the authors compare the measurement characteristics of a multiple-station examination (MSE) using standardized patients with those of a video assessment of regular consultations in daily practice (practice video assessment, PVA). METHOD: In a cross-sectional study, consultations of 90 family physicians were videotaped both in an MSE and in their daily practices. Peer-observers used a validated instrument (MAAS-Global) to assess the physicians' communication with patients and their medical performances. The physicians were randomly divided into two groups, comparable for demographic characteristics, and half underwent the assessments in reverse order to test for time-order effects. Content validity, criterion validity, reliability, and feasibility of the two methods were compared. RESULTS: Content validity of the PVA was superior to that of the MSE, since the domain of general family practice care was better covered. Observed participants judged the videotaped practice consultations to be "natural," whereas hardly any family physician, after reviewing the videotaped consultations of the MSE, recognized his or her usual working style. Specific criteria made it possible to standardize real practice. Concerning criterion validity, only the medical-performance components of the two methods correlated. No correlation was found for the communication components. Real-practice performance proved to be less influenced by observation than was performance during the MSE. The reliabilities of the two methods, expected to be better in the controlled MSE, were comparable. The administration of the PVA was more flexible, less costly, and better accepted by the family physicians than was that of the MSE. CONCLUSION: Assessment for quality improvement of family physicians' practices by video observation in daily practice is superior to video assessment in a simulated setting using standardized patients. 相似文献
40.
BACKGROUND AND PURPOSE: A diagnosis of cancer is a contraindication for the use of therapeutic ultrasound (US). Continuous US applied to murine tumors has resulted in larger and heavier tumors compared with controls. We compared tumor growth using low-power continuous US and energy-matched pulsed US. SUBJECTS: Female C57BL/6 mice (N = 174) were used. METHODS: Animals received subcutaneous injections of methylcholanthrene tumor cells. The mice were randomly divided into three groups: 60 mice that received low-power continuous US for 5 minutes at 0.75 W/cm2 (LC US group), 63 mice that received pulsed US for 12.5 minutes at 1.5 W/cm2 (pulsed US group), and 51 mice that served as a control group. The LC and pulsed US groups received equal US energy. Both experimental groups received 10 treatments of 3-MHz US, which was applied directly over the tumor. The control group received identical handling but no US. After treatment, the tumors were excised, weighed, and measured. A one-way analysis of variance, followed by Newman-Keuls post hoc testing, was used to analyze the data. RESULTS: Mean tumor weights (in grams) and volumes (in cubic millimeters) were 0.563 g and 564 mm3 for the LC US group, 0.560 g and 525 mm3 for the pulsed US group, and 0.516 g and 406 mm3 for the control group. CONCLUSION AND DISCUSSION: Reducing total US energy will result in less growth of murine tumors. When infusing equal energy, continuous and pulsed US will produce similar effects on tumor growth. 相似文献