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71.
Stroud SD Erkel EA Smith CA 《Journal of the American Academy of Nurse Practitioners》2005,17(2):67-75
PURPOSE: To describe the prevalence and patterns of use of personal digital assistants (PDAs) by nurse practitioner (NP) students and faculty, examine relationships between patterns of use of PDAs and demographic characteristics of NP students and faculty, and describe patterns of use of PDAs that support evidence-based practice (clinical scholarship). DATA SOURCES: Responses to a 20-item questionnaire administered via electronic or postal mail from 227 NP students and faculty. CONCLUSIONS: A majority (67%) of the participants used PDAs. Use was higher among men (82%) than women (64%) (p < .05). On average, respondents who used a PDA (N = 153) had been using it just over a year (M = 13 months). Respondents reported using a PDA most days of the week (M = 5 days). The top three medical software programs identified by respondents as the most useful in clinical practice were ePocrates Rx (82%), Griffith's 5-Minute Clinical Consult (26%), and MedCalc (22%). Most participants (96%) related that PDA use supported clinical decision making. IMPLICATIONS FOR PRACTICE: Personal digital assistants may facilitate the application of evidence-based knowledge to practice. However, until there is evidence that PDA software is valid and reliable, clinicians should continue to use a multitude of references to assure the quality and safety of care provided. 相似文献
72.
Serologic test for syphilis as a surrogate marker for human immunodeficiency virus infection among United States blood donors 总被引:2,自引:0,他引:2
GA Herrera ; EM Lackritz ; RS Janssen ; VP Raimondi ; RY Dodd ; J Aberle-Grasse ; LR Petersen 《Transfusion》1997,37(8):836-840
BACKGROUND: This study evaluated the usefulness of the serologic test for syphilis (STS) in preventing the transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses, and human T- lymphotropic virus via the transfusion of seronegative, infectious window-period blood. STUDY DESIGN AND METHODS: Demographic and laboratory information on blood donations made between January 1992 and June 1994 in 18 American Red Cross regions was analyzed. It was assumed that the same proportion of HIV-positive and HIV-infectious window- period donations reacted on STS and were negative on other screening tests (hepatitis B and C viruses and human T-lymphotropic virus). This proportion multiplied by the estimated number of HIV-infectious window- period donations is the number of post-screening HIV-infectious donations removed by STS. RESULTS: Of 4,468,570 donations, 12,145 (0.27%) were STS positive and 377 (0.008%) were HIV positive. Among donations that were negative on other screening tests, STS-reactive donations were 12 times more likely to be HIV positive (odds ratio = 11.9; 95% CI = 5,26). However, of an estimated 13 infectious window- period donations, 0.2 would have been removed because of a reactive STS, at a cost of over $16 million. CONCLUSION: STS is a poor marker and a costly strategy for preventing post-screening HIV infections and other blood-borne diseases. 相似文献
73.
74.
Pharyngeal pump and esophageal transit 总被引:3,自引:0,他引:3
A. G. Buthpitiya MBBS MS D. Stroud MSc PhD C. O. H. Russell MBChB MS FRACS 《Digestive diseases and sciences》1987,32(11):1244-1248
In deglutition the pharynx appears to act as a pump to inject boluses into the esophagus. A new method for measuring the velocity profile of the leading edge of a radionuclide bolus has been developed and applied to boluses of different viscosity—water and treacle—in nine normal volunteers. The results show that the more viscous bolus (treacle) acquires a slower initial injection velocity (152 mm/sec vs 236 mm/sec) that only propels it over the proximal half of the esophagus. Peristaltic action must drive the bolus over the distal half. With water boluses, however, the higher initial velocity is sufficient to propel a part of the bolus at least to the gastroesophageal junction leaving minimal work to be performed by esophageal peristalsis. This confirms the important role of the pharyngeal pump in deglutition. The pump may be the major mechanism for ingestion of nonviscous liquids (water), peristalsis merely being required to sweep up what remains in the esophagus. 相似文献
75.
Adaptive differentiation of murine lymphocytes. IV. (Responder × Nonresponder) F(1) T cells can be taught to preferentially help nonresponder,rather than responder, B cells 下载免费PDF全文
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type. 相似文献
76.
Paiardini M Hoffman J Cervasi B Ortiz AM Stroud F Silvestri G Wilson ME 《Brain, behavior, and immunity》2009,23(2):286-293
Increased vulnerability to psychosocial stressors likely predisposes individuals to decreased immune function and inability to control pathogens. While many factors influence the susceptibility to psychosocial stress, genetic polymorphisms may modify individual reactivity to environmental stressors. The present study evaluated how immune function was altered by the interaction of in polymorphisms in the gene that encodes the serotonin reuptake transporter (5HTT) and the psychosocial stress imposed by social subordination in adult female rhesus monkeys. Subjects were dominant and subordinate females that carried both alleles of the long promoter variant (l/l) of the 5HTT gene, and dominant and subordinate that had at least one allele for the short promoter length variant (l/s or s/s, s-variant). Plasma cortisol was higher in subordinate females in response to a social separation paradigm, confirming their increased reactivity to psychosocial stressors. Subordinate females exhibited increased T-cell activation and proliferation regardless of genotype. Despite these higher levels of T-cell proliferation and activation, subordinate females showed significantly lower frequency of T-cells. This latter finding may be due to an increased susceptibility to cell death, as indicated by higher levels of annexin-V+ CD4+ and CD8+ T-cells in s-variant subordinate compared to dominant females. These findings indicate that subordinate rhesus monkeys with the s-variant 5HTT genotype exhibit decreased T-cell numbers perhaps compromising their ability to mount an immune response to pathogens. These data underscore the importance for considering gene polymorphisms that influence emotional reactivity to better understand susceptibility to disease. 相似文献
77.
Morris MJ Gannan E Stroud LM Beck-Sickinger AG O'Brien TJ 《The European journal of neuroscience》2007,25(4):1136-1143
Neuropeptide Y (NPY) potently suppresses absence seizures in a model of genetic generalized epilepsy, genetic absence epilepsy rats of Strasbourg (GAERS). Here we investigated the Y-receptor subtype(s) on which NPY exerts this anti-absence effect. A dual in vivo approach was used: the cumulative duration of seizures was quantified in adult male GAERS in 90-min electroencephalogram recordings following intracerebroventricular (i.c.v.) injection of: (i) subtype-selective agonists of Y1 ([Leu31Pro34]NPY, 2.5 nmol), Y2 (Ac[Leu(28,31)]NPY24-36, 3 nmol), Y5 receptors [hPP1(-17),Ala31,Aib32]NPY, 4 nmol), NPY (3 nmol) or vehicle; and following (ii) i.c.v. injection of antagonists of Y1 (BIBP3226, 20 nmol), Y2 (BIIE0246, 20 nmol) and Y5 (NPY5RA972, 20 nmol) receptors or vehicle, followed by NPY (3 nmol). Injection of the Y1- and Y5-selective agonists resulted in significantly less mean seizure suppression (37.4% and 53.9%, respectively) than NPY (83.2%; P < 0.05), while the Y2 agonist had similar effects to NPY (62.3% suppression, P = 0.57). Food intake was not increased following injection of the Y2 agonist, while significant increases in food intake were seen following NPY and the other Y-subtype agonists. Compared with vehicle, NPY injection suppressed seizures following the Y1 and Y5 antagonists (45.3% and 80.1%, respectively, P < 0.05), but not following the Y2 antagonist (5.1% suppression, P = 0.46). We conclude that NPY Y2 receptors are more important than Y1 and Y5 receptors in mediating the effect of NPY to suppress absence seizures in a genetic rat model. Y2 receptor agonists may represent targets for novel drugs against genetic generalized epilepsies without resulting in appetite stimulation. 相似文献
78.
79.
背景和目的:国际5国脑血管病专家提出一种新的腩卒中亚型分类法,旨在介绍完整的"脑卒中表型"分类的新观念,该分类是包括脑卒中的病因和存在的所有病因相关的疾病,并将病因疾病按严重程度分成3级. 相似文献
80.
Mennigen JA Stroud P Zamora JM Moon TW Trudeau VL 《Journal of toxicology and environmental health. Part B, Critical reviews》2011,14(5-7):387-412
Pharmaceuticals are increasingly detected in a variety of aquatic systems. One of the most prevalent environmental pharmaceuticals in North America and Europe is the antidepressant fluoxetine, a selective serotonin reuptake inhibitor (SSRI) and the active ingredient of Prozac. Usually detected in the range below 1 μg/L, fluoxetine and its active metabolite norfluoxetine are found to bioaccumulate in wild-caught fish, particularly in the brain. This has raised concerns over potential disruptive effects of neuroendocrine function in teleost fish, because of the known role of serotonin (5-HT) in the modulation of diverse physiological processes such as reproduction, food intake and growth, stress and multiple behaviors. This review describes the evolutionary conservation of the 5-HT transporter (the therapeutic target of SSRIs) and reviews the disruptive effects of fluoxetine on several physiological endpoints, including involvement of neuroendocrine mechanisms. Studies on the goldfish, Carassius auratus, whose neuroendocrine regulation of reproduction and food intake are well characterized, are described and represent a reliable model to study neuroendocrine disruption. In addition, fish studies investigating the effects of fluoxetine, not only on reproduction and food intake, but also on stress and behavior, are discussed to complement the emerging picture of neuroendocrine disruption of physiological systems in fish exposed to fluoxetine. Environmental relevance and key lessons learned from the effects of the antidepressant fluoxetine on fish are highlighted and may be helpful in designing targeted approaches for future risk assessments of pharmaceuticals disrupting the neuroendocrine system in general. 相似文献