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951.
We have examined the carotenoid contents of several dark green vegetables found to be associated with a lower risk of various epithelial cancers in our epidemiological study and animal study. Samples of these vegetables were quantitatively examined by high-performance liquid chromatography (HPLC) on a C-18 reversed-phase column for individual carotenoid content. Pure reference compounds (alpha-carotene, beta-carotent, lycopene, canthaxanthin, and lutein) and internal standard (beta-Apo-8'-carotenal) were employed to quantify xanthophylls and carotenes in these vegetables. The results indicated that fresh, dark-green, leafy vegetables were high in beta-carotene (0.94-9.36 mg/100 g) and oxygenated carotenoids or xanthophylls, primarily lutein (0.94-7.39 mg/100 g), whereas lycopene and alpha-carotene were not prominent and canthaxanthin was non existent in these vegetables. These analyses suggest that consumption of carotenoids such as lutein in addition to beta-carotene may be associated with a lower risk of cancers. 相似文献
952.
WJ Qui?ones-Baldrich MD Colburn SS Ahn HA Gelabert WS Moore 《Canadian Metallurgical Quarterly》1993,166(2):117-23; discussion 123
Forty-six bypass grafts to tibial arteries distal to the ankle were performed in 35 patients for salvage of extremities threatened by gangrene or nonhealing ulcers (grade III, category 5) or ischemic rest pain (grade II, category 4). Most patients (80%) were diabetic, with severely calcified arteries, whom previously we would have considered as candidates for primary amputation. All reconstructions were performed with autologous saphenous vein. Inflow was from the common femoral artery in 5 (11%), the popliteal artery in 25 (54%), or the mid-tibial arteries in 16 (35%). Life-table analysis was used to calculate primary patency and limb salvage. Results were analyzed according to origin of inflow, outflow, or configuration of the conduit (in situ saphenous vein, n = 29 [63%], reversed saphenous vein, n = 11 [24%], or nonreversed saphenous vein, n = 6 [13%]). Overall cumulative primary graft patency at 2 years for all grafts was 72%, and the cumulative limb salvage rate was 89% for the same interval. No significant differences were seen in comparing grafts originating from the femoral or popliteal level with those arising from the tibial arteries. No significant differences were noted in graft patency or limb salvage among grafts with a posterior tibial, dorsalis pedis, or plantar artery outflow. No significant difference was noted between in situ saphenous vein grafts and reversed saphenous vein grafts. A significant decreased primary patency was noted for grafts performed with nonreversed, translocated saphenous vein. We conclude that bypass grafts to the ankle or foot vessels are beneficial and should be considered for limb salvage in extremities with gangrene, ischemic ulceration, or ischemic rest pain. In our experience, in situ saphenous vein grafts or reversed saphenous vein grafts performed similarly, whereas nonreversed saphenous vein grafts have a poorer prognosis. Vessel wall calcification requires a modification in technique for performance of these grafts but did not affect long-term performance or limb salvage, and thus should not be considered a contraindication to vascular reconstruction. The operative microscope was used in 61% (28 of 46) of these cases and found useful in creating these delicate anastomoses. Additional follow-up is needed to document the long-term results of these very distal reconstructions. 相似文献
953.
Medical monitoring of patients is intended for controlling their physiological parameters, providing information to the medical staff as of critical, precritical physiological values, as well as for accumulating information on the patients' condition in time (trends). The existing monitoring systems require further improvement by expanding the types of measuring channels connected to them, providing a definite service, adaptability to a concrete medical institution. The basic orders to develop and produce such systems were got from the leading medical institutions of the Republic of Udmurt. A list of physiological parameters requiring monitoring, specifications of transducer systems and measuring channels (as a table), as well as demands by for channels, as required, records written down into the trend, as results is given. Possible variants of the design and use of computer monitors are provided. 相似文献
954.
SS Bachman 《Canadian Metallurgical Quarterly》1996,21(4):807-824
State governments fund more than one-half of public mental health service system costs through mental health departments, other state agencies, and the Medicaid program. They use some of these resources to finance community-based mental health services through purchase-of-service contracts. I explored the reasons why states privatize mental health services and focused on political, economic, and organizational theories as possible frameworks for contracting. I gathered data during site visits to Massachusetts, Michigan, New York, Oregon, Tennessee, and Texas, where I interviewed more than one hundred individual stakeholders about mental health purchase-of-service contracting. I also examined relevant documents about contracting practices for mental health services in each state. My results suggest that state policy makers can use mental health contracting to effect multiple goals. Contracting helps states achieve political, economic, and organizational objectives, such as avoiding the influence of interest groups and leveraging state resources, while avoiding conflict. With contracting, state policy makers can also continue the ongoing mental health policy paradigm shift begun during deinstitutionalization, in which persons with serious and persistent mental illnesses receive services from community-based providers rather than in state hospitals. Finally, my results suggest that contracting will continue to be an important state policy tool in further development of state-supported mental health systems. 相似文献
955.
956.
957.
J. A. Parkin 《Mechanism and Machine Theory》1990,25(6):689-699
A simple form of expression for writing down a screw which has undergone a transformation of reference frame is established. The simplifications it brings to the standard problems of identifying the principal axes of a screw system and of identifying the axis line of a finite twisting motion is demonstrated. 相似文献
958.
959.
We examined mechanisms that protect host defense cells from their cytotoxic effector molecules. Human neutrophil peptides (HNP) 1-3 are microbicidal and cytotoxic defensins, initially synthesized as 94-amino acid preproHNP(1-94), cotranslationally proteolyzed to proHNP(20-94), then converted by removal of the anionic propiece to mature HNP(65-94)(HNP-1 and -3) and HNP(66-94) (HNP-2). We hypothesized that during synthesis and subcellular sorting the anionic propiece inhibits the cytotoxicity of the cationic defensin. We expressed preproHNP-1 cDNA in recombinant baculovirus-infected insect cells that secreted the normally transient proHNP-1(20-94) into the medium. Cyanogen bromide cleaved proHNP-1(20-94) at the fortuitously located Met64 to yield mature recombinant HNP-1(65-94) and unlinked propiece. Recombinant and native HNP-1 purified from PMN were identical as judged by mass spectrometry, retention time in reverse-phase high performance liquid chromatography, migration on acid-urea polyacrylamide gels, and reaction with a conformation-specific antibody. Recombinant and native HNP-1 had comparable microbicidal activity towards Listeria monocytogenes and were similarly potent in permeabilizing K562 leukemia cells, but proHNP-1(20-94) was virtually inactive in both assays. Addition of unlinked propiece (proHNP-1(20-64) with Met64-->homoserine) inhibited the bactericidal and cell-permeabilizing activity of mature HNP-1 in a dose-dependent manner. Linked, and to a lesser extent unlinked, propiece interfered with the binding of HNP-1 to target cells. The propiece thus acts as an efficient intramolecular inhibitor of defensin HNP-1 cytotoxicity. 相似文献
960.
M Diamond SS Williams H Kida S Yokota RB Bankert 《Canadian Metallurgical Quarterly》1996,25(4):291-305
Previously we reported that human imunocompetent cells engrafted into scid mice mount a sustained and vigorous humoral immune response to murine erythrocytes. One of the dominant and consistently observed reactivity pattern of these antibodies in immunoblot analysis is with the alpha and beta isoforms of spectrin. In order to define the human xenoreactive response more completely, a hybridoma was generated (from a hu-PBL-scid mouse) whose antibody reacted with two high molecular weight species 225 to 250 kDa. We report here that this conserved antibody species reacts with both the murine and human erythrocyte proteins and cDNA nucleotide sequence analysis of the light and heavy chain genes encoding this antibody reveals that the light chain variable region gene has been previously observed in association with an autoreactive antibody. In addition to characterizing a conserved human B cell clonotype this is the first report of a human monoclonal antibody being generated from the hu-PBL-scid model using the standard hybridoma technology. 相似文献