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41.
42.
SP Newman J Brown KP Steed SJ Reader H Kladders 《Canadian Metallurgical Quarterly》1998,113(4):957-963
STUDY OBJECTIVES: To compare lung deposition of fenoterol or flunisolide administered from a novel, multidose inhalation device delivering liquid droplets (RESPIMAT; Boehringer Ingelheim Ltd; Bracknell, UK) or from conventional metered-dose inhalers (MDIs) with and without spacers. DESIGN: Two randomized, three-way crossover studies. SETTING: Clinical research laboratory. PARTICIPANTS: Healthy, nonsmoking volunteers. INTERVENTIONS: In one study, radiolabeled aerosols of fenoterol from the RESPIMAT device and from a conventional MDI with or without an Aerochamber spacer (Trudell Medical; London, Ontario Canada). In the second study, radiolabeled aerosols of flunisolide from a RESPIMAT device, from a RESPIMAT device modified by inclusion of a baffle/impactor in the mouthpiece, and from a conventional MDI with an Inhacort spacer (Boehringer Ingelheim; Ingelheim, Germany). MEASUREMENTS AND RESULTS: Assessment of the deposition of fenoterol or flunisolide in the lung and oropharynx using gamma scintigraphy. Safety was assessed based on reported adverse effects and spirometry (FEV1, FVC, and peak expiratory flow rate) to detect any paradoxical bronchoconstriction. The RESPIMAT device delivered significantly more fenoterol to the lungs than either an MDI alone or an MDI with Aerochamber (39.2% vs 11.0% and 9.9% of metered dose, respectively; p<0.01). Oropharyngeal deposition of fenoterol from the new device was lower than that from the MDI (37.1% vs 71.7%, respectively; p<0.01). The RESPIMAT device deposited significantly more flunisolide in the lungs compared with MDI plus spacer (44.6% vs 26.4%, respectively; p<0.01), while resulting in similar oropharyngeal deposition (26.2% vs 31.2%, respectively). Introduction of a baffle into the RESPIMAT system reduced lung deposition of flunisolide to 29.5%, and oropharyngeal deposition to 7.8% (p<0.01). CONCLUSION: The RESPIMAT device may prove to be an effective alternative to MDIs for the administration of inhaled bronchodilators and corticosteroids. The high lung deposition and low oropharyngeal deposition may lead to improved efficacy and tolerability of inhaled medications, especially corticosteroids. 相似文献
43.
Kinins lower blood pressure but the stimuli leading to kinin generation and their origin are less well known. We administered angiotensin II in graded infusion doses to patients with primary hypertension and normotensive controls to study the effects of on circulating kallikreins. Angiotensin II infusion did not significantly alter plasma prekallikrein or tissue kallikrein levels and the plasma levels and their changes did not correlate with blood pressure levels or changes. In the normotensive group prekallikrein levels and renin activity correlated negatively with urinary sodium and chloride excretion during basal conditions and partially during the infusion. U-tissue kallikrein concentration increased in the normotensive group. Thus, acute elevation of blood pressure induced by angiotensin II does not activate the circulating kallikrein-kinin systems. Data rather indicate that the circulating kallikrein-kinin systems may be related to alterations in volume and sodium balance and that these mechanisms may be altered in primary hypertension. 相似文献
44.
45.
KP Maier H Talke G Hoppe-Seyler J Fr?hlich P Schollmeyer G Sch?nbach KP Erhart W Gerok 《Canadian Metallurgical Quarterly》1976,54(21):1021-1025
Enzymes of the Krebs-Henseleit urea-cycle were localized by means of differential centrifugation and fractional tissue extraction in rat liver and in human liver. Argininosuccinatlyase (ASAL) and Argininosuccinatsynthetase (ASAS) represent enzymes of the soluble cytoplasmic fraction. Ornithine-ketoacid-transaminase(OKT), carbamyl-phosphate-synthetase (CPS) and ornithine-carbamyl-transferase (OCT) are localized in the mitochondrial and nuclei fractions of the liver cell. Most of the arginase activity is bound to subcellular structures (probably to nuclei). A small portion of arginase-activity was found in the soluble cytoplasmatic fraction. The enzymes of the Krebs-Henseleit urea-cycle are equally distributed in rat liver and in human liver. Differences in the subcellular localisation of (mitochondrial) enzymes in human liver could be attributed to mitochondrial breakage during tissue preparation and do not represent in-vivo conditions. 相似文献
46.
RM Gipstein JW Coburn DA Adams DB Lee KP Parsa A Sellers WN Suki SG Massry 《Canadian Metallurgical Quarterly》1976,136(11):1273-1280
Eleven patients with chronic renal failure and presumed secondary hyperparathyroidism developed a syndrome of medial calcinosis of the arteries and painful ischemic ulcers of the fingers, legs, or thighs, or any combination of the three. Five patients required maintenance hemodialysis; six had functioning renal homografts. Severe hyperphosphatemia had existed in each; seven showed roentgenographic evidence of subperiosteal resorption. Similarities are evident between the lesions and experimentally produced calciphylaxix. The lesions demonstrated a relentless, progressive course, with serious morbidity and mortality. Hyperplastic or adenomatours parathyroid tissue was removed from ten of 11 patients unergoing surgical procedures; healing followed in seven patients. Treatment with phosphate-binding antacids to lower serum phosphorus levels may prevent this syndrome. Total or subtotal parathyroidectomy should be considered when ischemic skin lesions appear in uremic patients or in renal transplant recipients. 相似文献
47.
48.
KP Robinson 《Canadian Metallurgical Quarterly》1976,58(6):440-451
A series of 165 primary amputations performed on 148 patients at Queen Mary's Hospital, Roehampton, from 1967 to 1975 is reported. The average age of these patients was 70 years, the oldest being 95. Those aged 70 years and over are considered in special detail. The problems of management of these elderly patients are complex, involving medical, surgical, and social problems. The object of treatment is to restore these patients to their previous way of life with the shortest possible time in hospital. Every patient is assessed with a view to arterial surgery, and amputation is avoided where possible by a lumbar sympathetic block or direct arterial surgery. When amputation cannot be avoided a below-knee level is selected if possible. A long posterior flap technique is used which forms a myoplasty of the gastrocnemius muscle; thus the ischaemic anterior tibial skin is avoided. Before the operation the patient is assessed by a specialist team and the management is discussed in detail. Every patient is kept in hospital until rehabilitation is achieved to the point of independence inside the home. Of the 90 patients in the group aged 70 years and over, 22% had above-knee amputations and 75% had below-knee amputations, with the result that 69% of the latter were discharged home walking. This result is contrasted with the smaller number who had an above-knee amputation. Below-knee amputation gives the elderly patient a better chance of walking because of the use of the patellar tendon bearing prosthesis. When followed up 36% of those patients with below-knee amputation were fully independent for periods exceeding six months. The price of a below-knee level of amputation is a longer hospital stay, but the quality of function and mobility obtained by the patient makes this worth while. 相似文献
49.
The concepts of fluid and rigid boundaries were assessed in an improvisational role-playing task in an attempt to differentiate paranoid from nonparanoid schizophrenics. Thirty-one schizophrenic patients divided into paranoid, intermediate, and nonparanoid groups were given an improvisational role-playing task. The resulting scenes were analyzed by Fluid Boundary and Rigid Boundary scales, which were developed on the basis of specific aspects of the physical and verbal representations of characters, objects, and settings. The hypothesis that variations in the disruption or emphasis of representational boundaries differentiate paranoid and nonparanoid symptomatology received support. Paranoid schizophrenics scored higher on the Rigid Boundary scale, i.e erecting and/or exaggerating physical and interpersonal boundaries; and nonparanoid schizophrenics scored higher on Fluid Boundary scale, i.e. showing fused and fluid representations of characters, objects, and settings. Improvisational role-playing seems to hold promise as a medium with diagnostic value. 相似文献
50.
H Tanaka CA Desouza PP Jones ET Stevenson KP Davy DR Seals 《Canadian Metallurgical Quarterly》1997,83(6):1947-1953
Using a meta-analytic approach, we recently reported that the rate of decline in maximal oxygen uptake (VO2 max) with age in healthy women is greatest in the most physically active and smallest in the least active when expressed in milliliters per kilogram per minute per decade. We tested this hypothesis prospectively under well-controlled laboratory conditions by studying 156 healthy, nonobese women (age 20-75 yr): 84 endurance-trained runners (ET) and 72 sedentary subjects (S). ET were matched across the age range for age-adjusted 10-km running performance. Body mass was positively related with age in S but not in ET. Fat-free mass was not different with age in ET or S. Maximal respiratory exchange ratio and rating of perceived exertion were similar across age in ET and S, suggesting equivalent voluntary maximal efforts. There was a significant but modest decline in running mileage, frequency, and speed with advancing age in ET. VO2 max (ml . kg-1 . min-1) was inversely related to age (P < 0.001) in ET (r = -0.82) and S (r = -0.71) and was higher at any age in ET. Consistent with our meta-analysic findings, the absolute rate of decline in VO2 max was greater in ET (-5.7 ml . kg-1 . min-1 . decade-1) compared with S (-3.2 ml . kg-1 . min-1 . decade-1; P < 0. 01), but the relative (%) rate of decline was similar (-9.7 vs -9. 1%/decade; not significant). The greater absolute rate of decline in VO2 max in ET compared with S was not associated with a greater rate of decline in maximal heart rate (-5.6 vs. -6.2 beats . min-1 . decade-1), nor was it related to training factors. The present cross-sectional findings provide additional evidence that the absolute, but not the relative, rate of decline in maximal aerobic capacity with age may be greater in highly physically active women compared with their sedentary healthy peers. This difference does not appear to be related to age-associated changes in maximal heart rate, body composition, or training factors. 相似文献