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991.
992.
Lung diffusing capacity for carbon monoxide (DLco) and its components, membrane diffusing capacity (Dmco) and capillary blood volume (Vc), as well as pulmonary blood flow (Qc), were measured at rest at several lung volumes and during treadmill exercise by a rebreathing technique in four adult dogs after right pneumonectomy (R-PNX) and in six matched control dogs (Sham) 6-12 mo after surgery. In both groups, lung inflation at rest was associated with a small increase in DLco and Dmco but not in Vc. After R-PNX, total DLco was lower by 30% at peak exercise compared with control values. When compared with DLco in a normal left lung, DLco in the remaining lung continued to increase along the normal relationship with respect to Qc up to a cardiac output equivalent to 34 l/min through both lungs of the Sham dog. There was no evidence of an upper limit of DLco being reached. The augmentation of DLco from rest to exercise was associated with corresponding increases in Dmco and Vc; after R-PNX, both Dmco and Vc continued to increase with respect to Qc along similar relationships as in control dogs without reaching an upper limit, suggesting a much larger alveolar-capillary reserve for gas exchange by diffusion than previously recognized. At higher levels of blood flow through the remaining lung, DLco was greater in adult dogs after R-PNX than after left pneumonectomy (Carlin et al. J. Appl. Physiol. 70: 135-142, 1991), suggesting that additional sources of compensation, e.g., lung growth, exist after removal of > 50% of lung. 相似文献
993.
994.
995.
996.
Decentralization in the New York City Department of Health: reorganization of a public health agency
Since the World War I era there has existed within the New York City Department of Health a basic internal struggle between staff directing the bureaus at the central office and the district health officers operating field health centers throughout the city. Recently, in a five-year period, there was a dramatic reorganization of the Department which markedly affected its orientation and programs. In 1972 a new Commissioner initiated a reorganization of the Department which succeeded in decentralizing field operations in contrast to earlier efforts which had failed to reach this objective. The roles of bureaus and districts were redefined, with the latter receiving budgetary authority, authority to supervise personnel, assignment of health managers, and the implementation of a district cost accounting system. While operational decentralization has occurred, policy setting and resource allocation in response to local needs remain central functions. 相似文献
997.
A rapid, convenient thin layer chromatographic (TLC) method for detecting histamine in fish samples is described. Samples of press juice or fish flesh are applied directly to TLC plates. The plates are developed with acetoneammonium hydroxide (95+5) and the spots are visualized with ninhydrin or Pauly's reagent. Chromatographic separation of histamine from other fish components is readily achieved by this method. 相似文献
998.
VR Sobolev IV Vlasova VE Solov'eva LF Bogdanova NE Smirnova 《Canadian Metallurgical Quarterly》1975,20(6):529-532
Seven antibiotics, such as gentamycin, kanamycin, streptomycin, polymyxin M, carbenicillin, tetracycline and rifampicin were studied with respect to their effect on 260 strains of Ps. aeruginosa isolated from various sources within 1945-1971. Gentamycin and polymyxin M proved to be most active in vitro. Carbenicillin showed moderate activity. The sensitivity levels of the cultures of Ps. aeruginosa isolated from various sources within 30 years were identical. Serological typing of 59 cultures of Ps. aeruginosa was performed and their virulence was studied in parallel with their antibiotic sensitivity testing. No correlation between the antibiograms, serotypes and virulence of Ps. aeruginosa was found. 相似文献
999.
1000.