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71.
Body size plays an important role in pinniped ecology and life history. However, body size data is often absent for historical, archaeological, and fossil specimens. To estimate the body size of pinnipeds (seals, sea lions, and walruses) for today and the past, we used 14 commonly preserved cranial measurements to develop sets of single variable and multivariate predictive equations for pinniped body mass and total length. Principal components analysis (PCA) was used to test whether separate family specific regressions were more appropriate than single predictive equations for Pinnipedia. The influence of phylogeny was tested with phylogenetic independent contrasts (PIC). The accuracy of these regressions was then assessed using a combination of coefficient of determination, percent prediction error, and standard error of estimation. Three different methods of multivariate analysis were examined: bidirectional stepwise model selection using Akaike information criteria; all‐subsets model selection using Bayesian information criteria (BIC); and partial least squares regression. The PCA showed clear discrimination between Otariidae (fur seals and sea lions) and Phocidae (earless seals) for the 14 measurements, indicating the need for family‐specific regression equations. The PIC analysis found that phylogeny had a minor influence on relationship between morphological variables and body size. The regressions for total length were more accurate than those for body mass, and equations specific to Otariidae were more accurate than those for Phocidae. Of the three multivariate methods, the all‐subsets approach required the fewest number of variables to estimate body size accurately. We then used the single variable predictive equations and the all‐subsets approach to estimate the body size of two recently extinct pinniped taxa, the Caribbean monk seal (Monachus tropicalis) and the Japanese sea lion (Zalophus japonicus). Body size estimates using single variable regressions generally under or over‐estimated body size; however, the all‐subset regression produced body size estimates that were close to historically recorded body length for these two species. This indicates that the all‐subset regression equations developed in this study can estimate body size accurately. 相似文献
72.
LTC Edwin S. Beatrice MC Georg D. Frisch MBA 《Archives of environmental & occupational health》2013,68(5):322-326
The eyes of rhesus monkeys were exposed to argon (514.5 nm) and ruby (694.3 nm) laser irradiation using various retinal image diameters which were estimated by microphotometric techniques. The experimental design for both wavelengths produced image diameters of 40μ to 50μ for the “minimal” case and approximately 500μ to 1,000μ for the larger irradiance series employed. Extramacular retinal exposure sites were examined by ophthalmoscopic and histopathological techniques. Flat preparations of the pigmented epithelium and sensory layers of the retina were utilized in the confirmation of damage at low power levels. All data were statistically analyzed to establish trends, and results were compared for the wavelengths employed. Results indicate that retinal damage is primarily dependent on energy distribution as a function of image diameter and exposure duration. 相似文献
73.
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75.
Glycoprotein Ib and glycoprotein IX are fully complexed in the intact platelet membrane 总被引:3,自引:6,他引:3
Two new murine monoclonal antibodies, AK 1 and SZ 1, reactive with the human platelet glycoprotein (GP) Ib-IX complex have been produced by the hybridoma technique. Both AK 1 and SZ 1 immunoprecipitated the GP Ib-IX complex from Triton X-100-solubilized, periodate-labeled platelets. With trypsinized, labeled platelets, AK 1, SZ 1, and FMC 25 (epitope on GP IX) immunoprecipitated a membrane-bound proteolytic fragment of the GP Ib-IX complex consisting of GP IX and an congruent to 25,000 mol wt remnant of the alpha-chain of GP lb disulfide-linked to the beta-subunit. Unexpectedly, although AK 1 and SZ 1 immunoprecipitated purified GP Ib-IX complex, neither antibody immunoprecipitated the individual components of this complex, GP Ib or GP IX. When GP Ib and GP IX were recombined, however, AK 1 and SZ 1 again immunoprecipitated the reformed complex, strongly suggesting that both antibodies were recognizing an epitope present only on the intact complex. Cross-blocking studies indicated that AK 1 and SZ 1 recognized a very similar or identical epitope that was proximal to the epitope for FMC 25. Both AK 1 and SZ 1 bound to a similar number of binding sites (congruent to 25,000) on intact platelets as monoclonal antibodies directed against either GP lb or GP IX. The combined data suggests that GP lb and GP IX are fully complexed in the intact platelet membrane. 相似文献
76.
Myeloproliferative syndrome induced by MPSV in DBA/2 mice: presence of a mixed-colonies promoting activity (MPA) in the spleen 总被引:1,自引:0,他引:1
Le Bousse-Kerdiles MC; Smadja-Joffe F; Klein B; Jasmin C; Comisso M; Ostertag W 《Blood》1983,61(3):520-524
The myeloproliferative syndrome induced by the myeloproliferative sarcoma virus (MPSV) in DBA/2 mice stimulates the proliferation of pluripotent hemopoietic stem cells (HSC) and of progenitors committed toward granulomacrophagic and erythroid cell lines. This stimulation may result from a direct effect of the MPSV on HSC or from an indirect effect via locally secreted factors. Normal isogenic bone marrow cells were incubated in the mixed colony-forming unit system in semisolid medium supplemented with conditioned media obtained after incubating neoplastic spleen cells for 3 days at 37 degrees C. These spleen conditioned media contain an activity that is physically separable from MPSV by ultracentrifugation and which, in the presence of a very low quantity of erythropoietin, can induce in vitro the proliferation and differentiation of pluripotent HSC, detected by this Mix-CFU technique. We termed this activity mixed-colonies promoting activity (MPA). These results suggest that the hyperplasia of the nonlymphoid hematopoietic system in the neoplastic spleen results from an indirect effect of the MPSV on pluripotent HSC via locally secreted factors. 相似文献
77.
Locating Ath8, a locus for murine atherosclerosis susceptibility and testing several of its candidate genes in mice and humans 总被引:3,自引:0,他引:3
Korstanje R Eriksson P Samnegård A Olsson PG Forsman-Semb K Sen S Churchill GA Rollins J Harris S Hamsten A Paigen B 《Atherosclerosis》2004,177(2):443-450
A previous study revealed that the difference in susceptibility to atherosclerotic lesions between inbred mouse strains SM/J and NZB/BlNJ was determined by one major locus (Ath8). In this study a (SM/J x NZB/BlNJ) F(1) x SM/J backcross localized Ath8 by quantitative trait locus mapping to chromosome 4 with a suggestive LOD score of 2.7. This quantitative trait locus (QTL) was confirmed using an (SM/J x NZB/BlNJ) intercross; Ath8 mapped to a 23cM region with a significant LOD score of 3.6. The genes for toll-like receptor 4 (T1r4), arachidonic acid epoxygenase (Cyp2j5), and angiopoietin-like protein 3 (Angptl3) map to this region. These candidate genes were analyzed for expression and sequence differences in the mouse and for associations with cardiovascular traits in human. Sequence analysis of Angptl3 shows a base pair substitution in SM, the susceptible strain, giving rise to an amino acid change in the fibrinogen homology domain of the protein. We found a significant association between ANGPTL3 and atherosclerotic lesions (P < 0.05) in human. These results suggest that Angptl3 is involved in atherosclerosis susceptibility in both mouse and human. 相似文献
78.
Judith K. Ockene Rashelle B. Hayes Linda C. Churchill Sybil L. Crawford Denise G. Jolicoeur David M. Murray Abigail B. Shoben Sean P. David Kristi J. Ferguson Kathryn N. Huggett Michael Adams Catherine A. Okuliar Robin L. Gross Pat F. BassIII Ruth B. Greenberg Frank T. Leone Kola S. Okuyemi David W. Rudy Jonathan B. Waugh Alan C. Geller 《Journal of general internal medicine》2016,31(2):172-181
Background
Early in medical education, physicians must develop competencies needed for tobacco dependence treatment.Objective
To assess the effect of a multi-modal tobacco dependence treatment curriculum on medical students’ counseling skills.Design
A group-randomized controlled trial (2010–2014) included ten U.S. medical schools that were randomized to receive either multi-modal tobacco treatment education (MME) or traditional tobacco treatment education (TE).Setting/Participants
Students from the classes of 2012 and 2014 at ten medical schools participated. Students from the class of 2012 (N?=?1345) completed objective structured clinical examinations (OSCEs), and 50 % (N?=?660) were randomly selected for pre-intervention evaluation. A total of 72.9 % of eligible students (N?=?1096) from the class of 2014 completed an OSCE and 69.7 % (N?=?1047) completed pre and post surveys.Interventions
The MME included a Web-based course, a role-play classroom demonstration, and a clerkship booster session. Clerkship preceptors in MME schools participated in an academic detailing module and were encouraged to be role models for third-year students.Measurements
The primary outcome was student tobacco treatment skills using the 5As measured by an objective structured clinical examination (OSCE) scored on a 33-item behavior checklist. Secondary outcomes were student self-reported skills for performing 5As and pharmacotherapy counseling.Results
Although the difference was not statistically significant, MME students completed more tobacco counseling behaviors on the OSCE checklist (mean 8.7 [SE 0.6] vs. mean?8.0 [SE 0.6], p?=?0.52) than TE students. Several of the individual Assist and Arrange items were significantly more likely to have been completed by MME students, including suggesting behavioral strategies (11.8 % vs. 4.5 %, p?<?0.001) and providing information regarding quitline (21.0 % vs. 3.8 %, p?<?0.001). MME students reported higher self-efficacy for Assist, Arrange, and Pharmacotherapy counseling items (ps?≤0.05).Limitations
Inclusion of only ten schools limits generalizability.Conclusions
Subsequent interventions should incorporate lessons learned from this first randomized controlled trial of a multi-modal longitudinal tobacco treatment curriculum in multiple U.S. medical schools.NIH Trial Registry Number: NCT0190561879.
Phase I trial of interleukin-2 after unmodified HLA-matched sibling bone marrow transplantation for children with acute leukemia 总被引:1,自引:1,他引:1
Robinson N; Sanders JE; Benyunes MC; Beach K; Lindgren C; Thompson JA; Appelbaum FR; Fefer A 《Blood》1996,87(4):1249-1254
Allogeneic bone marrow transplantation (BMT) for advanced acute leukemia is associated with a high risk of relapse. It is postulated that interleukin-2 (IL-2) administered after BMT might induce or amplify a graft-versus-leukemia effect and thereby reduce the relapse rate. To identify an IL-2 regimen for testing this hypothesis, a phase I trial of IL-2 (Roche) was performed in children in complete remission (CR) without active graft-versus-host disease (GVHD) off immunosuppressive agents after unmodified allogeneic matched-sibling BMT for acute leukemia beyond first remission. Beginning a median of 68 days after BMT, 17 patients received escalating doses of induction IL-2 (0.9, 3.0, or 6.0 x 10(6) IU/m2/d representing levels I, II, and III) for 5 days by continuous intravenous infusion (CIV). After 6 days of rest, they received maintenance IL-2 (0.9 x 10(6) IU/m2/d) for 10 days by CIV infusion. Levels I and II were well-tolerated, but, of 6 patients at level III, 1 developed pulmonary infiltrates, 1 developed hypotension (both resolved), and 1 died of bacterial sepsis and acute respiratory distress syndrome. Grade II acute GVHD developed in 1 patient at level I and 1 at level III. The maximum tolerated dose of induction IL-2 was level II. IL-2 induced lymphocytosis, with an increase in CD56+ and CD8+ cells. Ten patients remain in CR at 5+ to 67+ months. Thus, a regimen of IL-2 has been identified that did not induce a high incidence of acute GVHD when administered to children after unmodified allogeneic BMT. Its clinical activity will be assessed in a phase II trial. 相似文献
80.
Karl Pillemer Emily K. Chen Catherine Riffin Holly Prigerson MC Reid Leslie Schultz 《American journal of public health》2015,105(11):2237-2244
We employed the research-to-practice consensus workshop (RTP; workshops held in
New York City and Tompkins County, New York, in 2013) model to merge researcher
and practitioner views of translational research priorities in palliative care.
In the RTP approach, a diverse group of frontline providers generates a research
agenda for palliative care in collaboration with researchers. We have presented
the major workshop recommendations and contrasted the practice-based research
priorities with those of previous consensus efforts. We uncovered notable
differences and found that the RTP model can produce unique insights into
research priorities. Integrating practitioner-identified needs into research
priorities for palliative care can contribute to addressing palliative care more
effectively as a public health issue.Over the past 2 decades, palliative care has become established as a promising approach
for addressing the needs of individuals with life-threatening illnesses from a holistic,
interdisciplinary perspective. For this project, we defined palliative care as an
approach that improves the quality of life of patients and families facing the problems
encountered in life-threatening illness by preventing and relieving suffering. Core
components of palliative care include providing relief from pain and other distressing
symptoms, affirming dying as a normal process, integrating psychological and spiritual
aspects of care, enhancing the quality of life of patients, and offering support systems
to patients and their families to help them live as fully as possible until death
occurs.Research suggests that palliative care results in positive patient outcomes, greater
patient and family satisfaction, and significant cost savings.1,2 The American Public Health Association, the
World Health Organization, and the Institute of Medicine3–6 have identified the
development of a robust palliative care delivery system as a key public health issue
because of the documented ability of palliative care to deliver effective and efficient
patient- and symptom-focused care to a growing population in need.In its 2013 report the American Public Health Association specifically detailed the
public health implications of palliative care, acknowledged the growing burden of
advanced chronic illness and disease in older adults, and recommended key steps to
address the problem. This policy statement called for federal, state, and local efforts
to promote effective symptom management in populations with serious illness or at the
end of life. Other recommended initiatives included the development of a palliative care
workforce, educational programs to improve uptake and use of palliative and hospice
care, and research funding to support the expansion of palliative care initiatives.
Achieving these goals will require moving beyond traditional medical practices to
include both policies and initiatives at the public health level.Despite the potential of palliative care to address the mental and physical health needs
of individuals with advanced illness, significant knowledge gaps impede its reach and
effectiveness. Reports from scientific bodies and consensus workshops have highlighted
weaknesses in the literature and called for more research on palliative care and
improved research methods.7–10 Thus, although both interest in and demand for
palliative care are increasing, reviews of the knowledge base continue to lament the
lack of research on many key issues.11,12Especially urgent is a research agenda that fits most closely with the needs of providers
who deliver palliative care. The systematic engagement of community practitioners in a
consensus process can lead to particularly useful and actionable recommendations for
research,13–15 which are greatly needed at this stage in the
development of the field. Therefore, to shed new light on research priorities in
palliative care, we used a structured, participatory method designed to solicit
practitioner input on research priorities: the research-to-practice consensus workshop
(RTP) model.16We employed the RTP approach to identify knowledge gaps and types of studies that should
be conducted to improve providers’ ability to deliver palliative care most
effectively. This model harnesses practice wisdom by engaging clinicians, agency staff,
and other practitioners with researchers in a process of articulating and refining
research questions and research priorities that honors scientific expertise and practice
wisdom. 相似文献