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991.
Understanding the sociocultural context of prenatal care underuse by an immigrant population can suggest programmatic changes that result in more effective health care delivery. Ethnographic survey interviews of female Hmong clinic patients conducted in 1987/88 revealed that they objected to biomedical procedures and to being attended by several doctors; the women also reported poor communication with staff as a problem. Clinic reforms implemented in 1989/90 included hiring a nurse-midwife, reducing the number of pelvic examinations, expanding hours of operation, creating a direct telephone line to Hmong interpreters, and producing a Hmong-language prenatal health care education videotape. Women interviewed in 1993 reported a more positive clinic experience. 相似文献
992.
993.
William J. Rasdorf Lisa K. Spainhour Edward M. Patton Bruce P. Burns 《Engineering with Computers》1993,9(1):36-48
The research described herein concerns the integration of several components of engineering software using a relational database. More specifically, a conceptual finite element material preprocessing system for laminated fiber-reinforced thick composite materials is studied. In this computer-aided analysis (CAA) system, a materials database is integrated with several software components, including commercially available finite element analysis (FEA) programs and preprocessors, and tools for the design of laminated composite materials. The system focuses on assembling, manipulating and using composite materials data, resulting in the transfer of 2-D and 3-D composite materials property data into a finite element analysis program. The system is life-cycle in nature, supporting a composite through testing, analysis and design. it offers great versatility in its ability to use raw ply data from any source, design layups, and generate laminate properties and FEA materials data files. Despite the fact that such integrated systems are not new in many domains, they have not been successfully introduced to the redlm of composite materials analysis and design. This outcome is due largely to the nature of the materials themselves and the overhead they bring to the development of a successful life-cycle model. 相似文献
994.
995.
JC Skipper DJ Kittlesen RC Hendrickson DD Deacon NL Harthun SN Wagner DF Hunt VH Engelhard CL Slingluff 《Canadian Metallurgical Quarterly》1996,157(11):5027-5033
Human CD8+ CTL recognize peptides bound to class I MHC molecules on the surface of melanoma cells. Several peptides derived from melanocyte lineage-specific proteins have been identified as epitopes for HLA-A2 restricted melanoma-reactive CTL. Because less than half of melanoma patients express HLA-A2, it is important to identify CTL epitopes restricted by other common MHC molecules including HLA-A1 and -A3. We have generated HLA-A3-restricted human CTL that recognize one or more shared melanoma Ags. All of the melanomas recognized by one of these CTL lines express Pmel-17/gp100, and those that fail to express this Ag are not lysed. This CTL line also specifically recognizes the lymphoblastoid line C1R-A3 following infection with a recombinant vaccinia encoding the melanocyte lineage-specific protein Pmel-17/gp100. Thus, at least one Pmel-17/ gp100 peptide is an epitope for this CTL line. We have identified ALLAVGATK (Pmel-17/gp100 residues 17-25) as an epitope for this CTL line and have shown that it is naturally processed and presented by HLA-A3 on melanoma cells. A second HLA-A3-restricted melanoma-reactive CTL line recognizes at least one additional shared epitope. These findings suggest that cellular immune responses directed against multiple shared melanoma epitopes exist in the 20 to 25% of melanoma patients who express HLA-A3. In addition, immunotherapy directed against Pmel-17/gp100 and other shared melanoma Ags may be useful in a large subset of these patients. 相似文献
996.
The venous antithrombotic profile of naroparcil or (4-[4-cyanobenzoyl]-phenyl)-1.5-dithio-beta-D-xylopyranoside was investigated in the rabbit following single i.v. and oral administration. Naroparcil attenuated thrombus development in a Wessler stasis model of venous thrombosis (jugular vein) employing bovine factor Xa as a thrombogenic stimulus giving ED50 values of 21.9 mg/kg and 36.0 mg/kg after respectively i.v. and oral administration. Venous antithrombotic activity was maximal 2-3 h after i.v. administration and 4-8 h after oral administration. Four hours after the oral administration of maximal antithrombotic (Wessler model, factor Xa) doses (100 and 400 mg/kg), naroparcil had no significant effect on bleeding time. In platelet poor plasma obtained from animals treated 4 h previously with various doses (25 to 400 mg/kg) of naroparcil, there was no detectable anti-factor Xa nor antithrombin activity. Similarly, naroparcil had no effect on APTT nor on thrombin time. A sensitized thrombin time (to about 35 s) was modestly but significantly increased following oral administration of the compound at 400 mg/kg. However, thrombin generation by the intrinsic pathway was reduced in a dose-related manner, maximal reduction being 65% at 400 mg/kg. The same dose of naroparcil enhanced the formation of thrombin/heparin cofactor II complexes at the expense of thrombin/antithrombin III complexes in plasma incubated with (125I)-human alpha-thrombin and induced the appearance of dermatan sulfate-like material in the plasma of treated rabbits, as measured by a heparin cofactor II-mediated thrombin inhibition assay.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
998.
Persons Jacqueline B.; Burns David D.; Perloff Jeffrey M.; Miranda Jeanne 《Canadian Metallurgical Quarterly》1993,102(4):518
293 psychiatric outpatients provided data to test the symptom specificity and final common pathway hypotheses about symptoms of depression and anxiety. The symptom specificity hypothesis predicts that the symptoms reported by a depressed or anxious patient depend on the dysfunctional beliefs he or she endorses. In contrast, the final common pathway hypothesis predicts that symptoms are unrelated to the types of beliefs the patient endorses. These hypotheses were tested in the context of theories that emphasize the importance of dysfunctional beliefs about achievement and attachment. Only limited support for the symptom specificity hypothesis was obtained; support was strongest for the link between attachment beliefs and anxiety symptoms. Relationships between symptoms and dysfunctional beliefs did not depend on psychiatric diagnosis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
More and more programmers find their software being used in performance critical applications. Unfortunately, they have limited techniques at their disposal to help guarantee this particular aspect of their programs. There has been considerable activity in recent years on developing analysis techniques for hard real-time systems. Inevitably these techniques make simplifying assumptions so as to reduce the complexity of the problem to be solved. For example hard real-time schedulability analysis techniques often assume that the timing properties of the underlying kernel can be accounted for by incorporating extra execution time into the application tasks. Furthermore, they assume that the application task structure is very simple and uniform. This paper considers the implications of using these techniques in the analysis of a typical single processor application, the attitude and orbital control system (AOCS) for the Olympus satellite. The paper outlines a common approach for estimating the response times for tasks, and then extends the scheduling equations so that they can be used in the engineering of realistic real-time systems. 相似文献
1000.
The specific activity of the microsomal delta 12-desaturase system, which transforms oleic acid into linoleic acid, was about 16 pmol/min/mg protein. However, most of the total activity was nonsedimentable even after a 200000 x g centrifugation for 100 min. The study of various physicochemical parameters showed that this enzymatic complex, functioning optimally between pH 7 and 8, had low thermal stability. Ca2+ which may cause an aggregation of the microsomes, and Hg2+ completely inhibited the activity, whereas Mg2+, Mn2+, and Zn2+ were activators. The delta 12-desaturase system was relatively specific toward oleic acid, though isomers of this fatty acid also had an action, either as substrates or as competitive inhibitors, on the activity of the system. The study of the effect of the exogenous oleoyl-CoA and elaidoyl-CoA on the specific activity of the delta 12-desaturase system showed a preference toward oleoyl-CoA. 相似文献