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31.
Long-term treatment of mouse cancer cells with interferon-alpha (IFN-alpha) converts parental B16 melanoma cells to B16alpha vaccine cells. Inoculation of syngeneic mice with B16alpha vaccine cells triggers immunity to the parental B16 tumor that is mediated by host macrophages, T cells, and natural killer (NK) cells. Lymph node cells from mice inoculated with irradiated B16alpha vaccine cells, but not with irradiated parental cells, proliferate when cultured in vitro, suggesting long-term in vivo activation of lymphoid cells. Long-term IFN-alpha treatment of B16alpha vaccine cells induced both interleukin-15 (IL-15) mRNA and IL-15 protein. The bulk of the induced IL-15 remained cell associated, either cytoplasmic or associated with the cell membrane. Immunofluorescence microscopy studies showed that the cell-associated IL-15 was broadly distributed throughout the cytoplasm. These observations suggest that long-term IFN-alpha treatment may induce primarily the truncated isoform of IL-15. Vaccination with irradiated B16alpha vaccine cells may promote tumor immunity by releasing high levels of cell-associated IL-15 when spontaneously lysed or directly killed by innate immune cells. The release of accumulated cell-associated IL-15 may then trigger a host T cell response to tumor antigens and cause host development of immunity to the B16 tumor cells.  相似文献   
32.
U Rose 《Arzneimittel-Forschung》1989,39(11):1393-1398
The anellated dihydropyridines 4a-l can be gained by Hantzsch-like synthesis from 5,5-dimethylcyclohexanedione (1), the aromatic aldehydes 2a-l and methyl-beta-aminocrotonate (3). Cyclisation of the side chains with bromosuccinimide or pyridiniumbromideperbromide leads to the octahydrofuro[3,4-b]chinoline-diones 4m-p. Structures of type 4 are characterized by the spectroscopic data. Positive inotropic effects, caused by calcium agonism, are exerted by the tested substances at the isolated, electrically stimulated left guinea pig atrium, 4j being the most potent with an intrinsic activity of 0.79, compared with ethyl 4-[2-(difluoromethoxy)phenyl]-1, 4,5,7-tetrahydro-2-methyl-5-oxo-furo[3,4-b]pyridine-3-carboxylate. BaCl2-induced contractions at the guinea pig ileum are suppressed dose-dependently.  相似文献   
33.
PURPOSE: To report the use of regional anesthesia and iv nitroglycerin to provide anesthesia and uterine relaxation for three Cesarean deliveries (CD) involving ex utero intrapartum treatment (EXIT) of potentially life-threatening airway obstruction in the newborn. CLINICAL FEATURES: Case 1--a 36-yr-old woman at 38 weeks' gestation was scheduled for an elective CD for fetal skeletal dysplasia and micrognathia. Case 2--a 34-yr-old woman at 35 weeks gestation had a fetal ultrasound revealing fixed neck flexion and micrognathia consistent with fetal arthrogryposis. Case 3--a 27-yr-old woman presented at 38 weeks gestation for CD for severe fetal micrognathia, with mandibular growth below the fifth percentile. For each case, a combined spinal epidural anesthetic was performed with 0.75% bupivacaine, fentanyl and morphine intrathecally followed by placement of a multiorifice epidural catheter. Prior to uterine incision patients received a loading dose followed by an iv infusion of nitroglycerin. Uterine relaxation was sufficient in all cases for delivery of the fetus, and allowed for evaluation by direct laryngoscopy and intubation while maintaining fetal-placental circulation. The surgical procedures were completed without incident. CONCLUSIONS: Anesthesia and uterine relaxation for CD and EXIT procedures can be safely provided with regional anesthesia and iv nitroglycerin.  相似文献   
34.
PurposeAlthough an adult model of patient-provider mutual exchange of information has been proposed, there is no guiding model for adolescents or measurement methodology. Our purpose was to develop a new scale of patient-provider interaction for adolescents accessing reproductive health care and at risk for sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV), and assess the reliability and validity of the scale.MethodsThe Adolescent Patient-Provider Interaction Scale (APPIS) was developed from the Roter and Hall theory of doctor-patient relationships, previously validated adolescent satisfaction and communication scales, and focus group and individual elicitation interviews. To assess construct validity, the new nine-item APPIS was compared with the satisfaction scale used by the Young Adult Health Care Survey (YAHCS), and Kahn’s Provider Communication Scale. Pearson correlation coefficients were used to examine convergence across scales, and factor analysis of the APPIS was performed.ResultsThe study recruited 192 African American girls aged 17.9 ± 1.7 years (range 15–21 years) from three sites: a county STD clinic (n = 51), urban adolescent clinic (n = 99), and a family planning clinic (n = 42). Most participants (85%) rated their overall health care highly (≥ 7 on a 10-point scale); 49% felt that both the provider and patient were “in charge” of the visit, and 88% “strongly agreed” or “agreed” that there was an equal “exchange of information” during the visit. The APPIS showed good internal consistency (Cronbach alpha = .75), and moderate convergence with the six-item YAHCS scale (r = .57, p < .001) and seven-item Kahn scale (r = .48, p < .001). Three factors emerged from exploratory factor analyses, supporting our conceptualization of patient-provider interaction as being multi-dimensional.ConclusionsA new theory-based scale of adolescent patient-provider interaction compares favorably with previous scales of health care satisfaction and communication. The new APPIS may be useful for evaluating approaches to improve health care outcomes for adolescents at-risk for STDs and HIV.  相似文献   
35.
OBJECTIVE: The authors describe their experience with left ventricular assist-device (LVAD) recipients undergoing noncardiac surgery and delineate surgical, anesthetic, and logistic factors important in the successful intraoperative management of these patients. SUMMARY BACKGROUND DATA: Left ventricular assist-devices have become part of the armamentarium in the treatment of end-stage heart failure. As the numbers of patients chronically supported with long-term implantable devices grows, general surgical problems that are commonly seen in other hospitalized patients are becoming manifest. Of particular interest is the intraoperative management of patients undergoing elective noncardiac surgical procedures. METHODS: The anesthesia records and clinical charts were reviewed for eight ventricular assist-device recipients undergoing general surgical procedures between August 1, 1990 and August 31, 1994. RESULTS: A total of 12 procedures were performed in 6 men and 2 women averaging 52.7 years of age. Mean time elapsed from device implantation to operation was 68 +/- 35 days. Conventional inhalational and intravenous anesthetic techniques were well tolerated in these patients undergoing diverse surgical procedures. No perioperative mortality was observed. Five of eight patients went on to successful cardiac transplantation. CONCLUSIONS: Hemodynamic recovery after LVAD insertion has defined a new group of patients who develop noncardiac surgical problems often seen in other critically ill patients. Recognition of the unique potential problems that the LVAD recipient may encounter in the perioperative period--in particular patient positioning, device limitations, and fluid and inotropic management--will ensure an optimal surgical outcome for LVAD recipients undergoing noncardiac surgery.  相似文献   
36.
Ventricular vagal nerve endings are thought to trigger vasodepressor syncope. Reports of vasodepressor reactions associated with donor bradycardia after cardiac transplantation have led to speculation that vagal reinnervation occurs. We assessed reinnervation status in seven patients 23–36 months (median 24 months) post-transplantation. Heart rate responses to vagal manoeuvres (respiration, Valsalva) and sympathetic stimuli (exercise and injection of tyramine into the coronary artery supplying the sinus node) were measured. All patients underwent 60 min of 60° head-up tilt with foot plate support. During tilt four of the seven had vasodepressor reactions with a fall in mean arterial pressure of 20–90 mmHg. During vasodepression two patients had falls in donor heart rate of 13 and 40% relative to peak heart rate during tilt. These two patients had evidence of functional sympathetic reinnervation. By contrast the two patients without donor bradycardia during vasodepression had only limited or no evidence of sympathetic reinnervation. No patient had consistent evidence of parasympathetic reinnervation as judged by the heart rate response to vagal manoeuvres. Headup tilt can thus produce vasodepressor reactions with donor bradycardia after cardiac transplantation in the absence of consistent evidence of vagal reinnervation. Left ventricular nerve endings may not be the only mediators of tilt-induced vasodepressor reactions in man. Donor bradycardia during vasodepression may reflect sympathetic withdrawal and not vagal reinnervation.  相似文献   
37.
Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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38.
This paper reports on the views of patients with established heart disease of a structured programme of follow-up care provided by practice nurses (PNs) in general practice in England. It is based on in-depth interviews with 22 patients receiving an integrated primary and secondary care intervention being developed and piloted for patients following heart attack or diagnosis of angina. Patients identified the important features of follow-up care to be easy access to a health professional who possessed knowledge and social and emotional skills. A range of views about the ability of PNs to provide such care emerged from patients' accounts. patients' perceptions about the seriousness of their condition and the way PN follow-up care was provided in practices emerged as important issues affecting patients' views. In addition, perceptions about the practice nurse's role, status and knowledge, existing relationships with general practitioners, and issues of communication were also important factors. It is concluded that in order to develop high-quality PN-led services for patients with established heart disease, four issues need to be taken into account: practice nurse training; continuity of follow-up care; the integration of the primary and secondary care interface; and development of the practice nurse's status within the primary health care team.  相似文献   
39.
Hypercoagulability in a patient with Marfan syndrome.   总被引:1,自引:0,他引:1       下载免费PDF全文
A 39 year old man with Marfan syndrome presented with multiple pulmonary emboli and renal, hepatic, and splenic infarcts of unknown aetiology. The combination of thromboemboli and physical features initially suggested homocystinuria; however, laboratory examination showed no evidence for this disorder. Laboratory evaluation identified no coagulation abnormalities. This patient represents the unusual occurrence of hypercoagulability in a patient with Marfan syndrome.  相似文献   
40.
Hypothesis: the aging paradox and autoimmune disease.   总被引:2,自引:0,他引:2  
E Talor  N R Rose 《Autoimmunity》1991,8(3):245-249
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