The University of California's (UC) online union catalog called MELVYL is examined. Aspects of MELVYL examined are computing resources, telecommunications, terminals for public use, evaluation of ...usage and necessary improvements, and the future of online catalogs in general. Planning and implementation of MELVYL began in 1979, and the system went online in the spring of 1981. It is available at all 9 UC campuses. Overall user response to MELVYL is very favorable, although one user survey indicates only 13.5% of users actually found what they were searching for in the catalog. Users appear to be expressing a favorable attitude toward the potential of the system rather than the actuality. Compared to the card catalog, most respondents found the online catalog faster and preferred it for finding recently published books, a few books on a subject, or a specific book. Users found MELVYL easier to learn to use than the card catalog. Added features requested by users include expansion of the database, an online thesaurus or some other method of viewing related search words, availability of a printout of search results, and check-out availability of the located material before leaving the terminal.
The availability of specific competitive antagonists stimulated investigation of the physiological and pathological role of angiotensin (A-II) and permitted the qualitative and quantitative ...characterization of numerous angiotensin receptor sites. The specific, competitive antogonists for A-II inhibit both the direct actions of A-II on isolated smooth muscle preparations and the stimulation of specific vascular receptor sites by which A-II evokes prostaglandin biosynthesis and release. Converting enzyme inhibitors a) block the action of exogenous A-I; b) lower blood pressure in conditions associated with high plasma renin levels (e.g., two-kidney renal hypertension, dehydrated diabetes insipidus rats, or in hemorrhagic shock); c) enhance responses to exogenous bradykinin (by inhibiting bradykininase); but d) do not block the effects of A-II at its receptor sites. A-II-receptor antagonists a) block the action of both A-I and A-II, b) lower blood pressure in high renin states, but c) have no effect on bradykinin degradation or action. Angiotensin receptor and synthesis antagonists have been shown to decrease the overall peripheral resistance and to reverse the renal cortical vasoconstriction during hemorrhagic shock and to prolong survival time in hemorrhaged dogs. It is our belief that angiotensin antogonists have therapeutic potential in hemorrhagic shock and would be expected (alone or in combination with alpha-andrenergic blockade) to overcome vascular shutdown and enhance organ perfusion (especially in the kidney).
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