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Claudia Gedlicka Gudrun Hager Martina Weissenböck Wilhelm Gedlicka Birgit Knerer Johannes Kornfehl Michael Formanek 《Journal of oral pathology & medicine》2006,35(8):472-478
BACKGROUND: 1Alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2) Vitamin D(3)] induces growth inhibition in squamous cell carcinoma (SCC) cell lines of the head and neck by arresting the cells in the G0/G1 phase of the cell cycle, probably due to an enhanced expression of p21, which could be demonstrated in other cell lines (JPPA, SCC9) before. In SCC25, a SCC cell line isolated from tongue, growth inhibition but no overexpression of p21 was detected. The retinoblastoma gene, as a direct target of G1 cyclin-CDK complexes, showed an obvious shift from the hyperphosphorylated to the hypophosphorylated form under 1,25(OH)(2)Vitamin D(3), which indicates that the growth inhibition takes place in the G0/G1 phase. To explore the possible pathway of growth inhibition in SCC25 we investigated other cell cycle inhibitors (p18, p19, p27). METHODS: Synchronized cells were treated with 1,25(OH)(2)Vitamin D(3) over 96 h. The cell cycle status and expression of cell cycle-regulating proteins was determined by fluorescence-activated cell sorting (FACS) and Western blotting. An overexpression of p18 in 1,25(OH)(2)Vitamin D(3) vs. ethanol-treated cells was determined until 30 h in SCC25. No influence was detectable on the expression of p27 and p19. CONCLUSION: One mechanism by which 1,25(OH)(2)Vitamin D(3) controls cell growth might be the upregulation of p21. As p21 was unsusceptible to 1,25(OH)(2)Vitamin D(3) in SCC25, other inhibiting proteins were necessary to be tested. The proven upregulation of p18 seems to be the responsible step for growth inhibition of 1,25(OH)(2)Vitamin D(3) in SCC25. 相似文献
3.
Teaching psychiatric ethics 总被引:1,自引:0,他引:1
S Bloch 《Medical education》1988,22(6):550-553
In the last decade, we have witnessed a burgeoning of interest in ethical issues amongst psychiatrists. Teaching of the subject, however, remains at a rudimentary stage. Various approaches to such instruction are available, particularly modelling (students observe their experienced counterpart), the case method (examining specific clinical situations which involve a need for ethical decision-making), and the seminar approach (trainees are exposed to a core body of knowledge, mainly theoretical in nature). Faced with these different teaching models, the University of Oxford Department of Psychiatry has opted for a blend of all three approaches, which incorporates two goals: an increase in the trainees' sensitivity to the many intricate moral dilemmas facing the psychiatric profession; and their familiarity with salient concepts in moral philosophy which constitute a basis for ethical reasoning and which have a bearing on clinical practice. The teaching programme comprises the following: a pair of trainees prepares a presentation on an aspect of psychiatric ethics under the supervision of a senior psychiatrist. A moral philosopher assumes the role of discussant of the ethical problems raised by the trainees; this is followed by a general discussion. Topics have included involuntary hospitalization, dual loyalty, suicide, psychiatric diagnosis, and ethical issues in various spheres of psychiatric practice such as sex therapy, psychotherapy and child psychiatry. The approach has worked effectively and proved rewarding to all participants involved. 相似文献
4.
Hinrich Böhner Detlef Kindgen-Milles Andreas Grust Rolf Buhl Wolf-Christian Lillotte Barbara T. Müller Eckhard Müller Günter Fürst Wilhelm Sandmann 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2002,387(1):21-26
BACKGROUND: The efficacy of nasal continuous positive airway pressure (nCPAP) as a prophylactic method for preventing cardiopulmonary complications after major vascular surgery has not been investigated. PATIENTS/METHODS: In a prospective randomized trial, 204 patients undergoing elective midline laparotomy for vascular surgery were randomized to receive standard therapy ( n=105) or additional prophylactic nCPAP ( n=99) for the first postoperative night. Postoperative oxygenation, incidence of severe cardiac, and pulmonary complications, length of intensive care surveillance and length of total postoperative hospital stay (LOS) were compared. RESULTS: Prophylactic nCPAP significantly reduced the number of patients with severe oxygenation disturbances defined as paO(2) < 70 mmHg with FiO(2) > or = 0.7 (5 versus 17, P=.01). There were no differences with respect to death, cardiac and pulmonary complications, length of intensive care surveillance or LOS. CONCLUSION: Prophylactic 12 h nCPAP significantly reduces the occurrence of postoperative oxygenation disturbances but has no effect on cardiac or pulmonary complications, need for intensive care, LOS or mortality after major vascular surgery. 相似文献
5.
Outcomes were compared between consecutive patients who had received either total lymphoid irradiation (TLI) or immunosuppressant treatment for intractable rheumatoid arthritis (RA). There were 33 TLI and 32 immunosuppressive recipients; all patients had failed standard therapy. Average followup from the start of therapy was 2.7 years for TLI and 5.9 years for immunosuppressive recipients. Final disability levels were the same in both groups; mortality was equal in both groups as well. There were more hospitalizations for infections in the TLI group and the infecting organisms tended to be staphylococcus or gram negative organisms. Apart from infections, there were more adverse effects reported in the immunosuppressive therapy group. 相似文献
6.
Hans-Peter Schlake Karl-Heinz Grotemeyer Ingolf Böttger Ingo Wilhelm Husstedt Günter Brune 《Neurosurgical review》1987,10(3):191-196
Migraine is considered to be a functional neurological disorder. In classical migraine (headache associated with prodromal visual field disturbances) and migraine accompagnée (headache associated with transient neurological symptoms), disturbances of cerebral blood flow and amine metabolism are thought to be pathogenetic factors. However, conventional methods of neuroimaging (CAT, NMR) usually do not yield any pathological findings in patients. Since 123I-iodoamphetamine (123I-IMP) crosses the intact blood brain barrier, 123I-IMP-SPECT is used for the assessment of cerebral perfusion in various neurological diseases, including functional disorders. 123I-IMP-SPECT was performed on 5 patients with classical migraine and 18 patients with migraine accompagnée. At the time of investigation, all patients were symptom-free. Cerebral blood flow was decreased in all patients with migraine accompagnée, and often corresponded to the site of headache as well as to the topography of transient neurological symptoms. This reduction was most obvious in a patient with persisting neurological symptoms. Most patients with classical migraine, however, did not show any alteration of cerebral perfusion. It appears that migraine--and in particular migraine accompagnée--is characterized by a permanent alteration not only of cerebral blood flow but also of neuronal activity. Migraine attacks may occur in connection with exacerbations of preexisting metabolic alterations. 相似文献
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8.
Ray Walker M.D. Debra Minor-Schork R.N. M.S.N. Richard Bloch Ph.D. James Esinhart Ph.D. 《The Psychiatric quarterly》1996,67(3):235-243
Objective. 1. To identify risk factors associated with psychiatric rehospitalization within six months, using global clinical assessments and demographic information and; 2. To determine if risk factors for a hospital in a rural region are similar to those reported for urban hospitals. Method. The setting was a psychiatric unit within a general hospital. All adult admissions for one year were assigned scores on the North Carolina Functional Assessment Scale (NCFAS) and the Global Assessment of Functioning (GAF) scale. Patients were interviewed six months after discharge to determine if they had been rehospitalized and to assign new NCFAS and GAF scores. Results. Significant risk of rehospitalization was predicted by: 1. NCFAS score >90; 2. history of prior hospitalization; 3. nursing home residence; 4. referral from a small community hospital and; 5. non-compliance with outpatient appointments. Conclusions. Global assessments and demographic information collected during an index admission can generate factors to identify patients at risk for rehospitalization within six months. History of prior admissions and non-compliance with outpatient treatment, reported as risk factors in urban settings, were found also to be risk factors in a rural region.He was formerly Assistant Professor, Center for Health Sciences Statistics, East Carolina University School of Medicine. 相似文献
9.
We tested the effects of pre-treatment with dexamethasone on topically induced ocular anaphylaxis in the rat. Rats were immunized with dinitrophenylated Ascaris suum extract and challenged with di-DNP-lysine. Dexamethasone was administered topically once (24, 6, or 1 h before challenge) or three times (6, 4, and 2 h before challenge). A single pre-treatment given at 24 or 6 h had no significant effect. A single pre-treatment 1 h before challenge reduced the extent of edema assessed histologically but not clinically, and had no significant effect on the eosinophil count in conjunctival tissue examined 6 h after challenge. Eyes pre-treated with dexamethasone 6, 4, and 2 h before challenge showed a significant reduction in conjunctival edema assessed histologically and clinically 1 h after challenge. In addition, 6 h after challenge the number of eosinophils was significantly reduced. We conclude that repeated pre-treatment with dexamethasone can suppress both the immediate phase and the cellular late phase of topically induced ocular anaphylaxis. 相似文献
10.
Conventional radiographs do not always make it possible to confirm a diagnosis of ischemic necrosis of the lunate in the early stages of disease. For these doubtful cases MRI is justifiable in addition, to diagnose or to rule out ischemic necrosis of the lunate. 相似文献