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1.
Hawi  N.  von Falck  C.  Krettek  C.  Meller  R. 《Der Unfallchirurg》2019,122(12):944-949
Die Unfallchirurgie - Zur Diagnostik von Schultergelenkerkrankungen wird routinemäßig die Magnetresonanztomographie (MRT) durchgeführt. Diese kann entsprechend der klinischen...  相似文献   
2.
F Bordi  E Meller 《Brain research》1989,504(2):276-283
Five components of behavior elicited by dopamine (DA) agonists (locomotor hyperactivity, sniffing, oral activity, grooming and paw nibbling) were evaluated after bilateral infusion of the selective D1 agonist fenoldopam (SKF 82526; 2.5-10 micrograms), the selective D2 agonist quinpirole (LY 171555; 5-40 micrograms) and the muscarinic cholinergic antagonist scopolamine (5-20 micrograms) into the ventral striatum of awake, unrestrained rats. Simultaneous bilateral infusion of various dose combinations of fenoldopam (2.5-10 micrograms) and quinpirole (5-20 micrograms) elicited dramatic increases in stereotyped behaviors relative to the effects produced by corresponding doses of each drug alone. Stereotyped sniffing and paw nibbling (self-directed oral activity) were markedly enhanced, whereas conventional oral behaviors (licking, chewing and/or biting) were either slightly or not at all increased. These potentiated responses were reduced or blocked by concomitant infusion of either the selective D1 antagonist SCH 23390 (1 and 5 micrograms) or the selective D2 antagonist sulpiride (0.15 microgram). Scopolamine (10 micrograms) only slightly increased the effects of quinpirole (5 micrograms) on both sniffing and oral behaviors, whereas it dramatically potentiated the effects of fenoldopam (2.5 micrograms) on oral activity; sniffing was only slightly increased. The effects of both drug combinations were almost completely antagonized by infusion of either SCH 23390 (1 microgram) or sulpiride (0.1 microgram). The results demonstrate that the synergistic effects of co-activation of D1 and D2 receptors observed after systemic administration are mediated at least in part by an interaction at the level of the striatum. Differences and similarities between the behaviors expressed after various treatments are discussed.  相似文献   
3.
4.
Within the treatment algorithm for accident victims there is an additional risk potential beyond those associated with the complex treatment procedures in primary medical care, and it is inherent in the interfaces between the different treatment sectors. Besides the substantial loss of time and information, such factors as technical incompatibilities between items of equipment, differing treatment concepts and responsibilities and difficulties in transfer and positioning can put the patient at risk. The entire process involves multiple interfaces both between preclinical and clinical medical care and within the various treatment sectors, e.g. when a preclinical patient is transferred from ground medical staff to the air rescue team. The goal of an efficient treatment algorithm should be the reduction of multiple interfaces in order to optimize the various procedures. Future concepts directed at optimizing trauma management should therefore make some contribution to interface reduction.  相似文献   
5.
Forty depressed patients and 36 age- and sex-matched controls were given 250 μg ACTH1–24 by bolus. Plasma steroid hormone levels were measured prior to and 60 min after ACTH administration. The depressed patients had significantly greater cortisol (F), 11-deoxycortisol (S), androstenedione (AD), and 17-hydroxyprogesterone (17-OHP) responses (delta; p<0.05) and a marginally greater 11β-hydroxyandrostenedione (11β-OHAD) response (delta; p=0.091) than the controls. There was no significant difference in the corticosterone (B) response between the two groups.

With the exception of 11β-OHAD, all the steroid hormones were significantly negatively correlated with age in the controls, but only S and AD marginally demonstrated this relationship in the depressed patients. F, S, AD, 17-OHP, and B, but not 11β-OHAD, were significantly positively correlated with each other in the controls, but only F was significantly correlated with AD in the depressed patients. These data suggest that the hypercortisolemia found in some depressed patients involves increased precursor and metabolite levels both at baseline and in response to exogenous ACTH, compared to controls. Furthermore, variability in these precursors is greater in depressed patients, and their relationship to age is lost. These findings are consistent with the hypothesis that adrenal products other than cortisol also could be related to affective symptoms.  相似文献   

6.
Forty-three children with malignant soft tissue sarcomas (IRS Groups II-IV) were treated with rapid dose delivery chemotherapy protocol comprising six courses of vincristine, adriamycin and cyclophosphamide, given in most cases within 8 weeks (Rapid VAC). This was followed in 36 patients by high dose melphalan with autologous bone marrow rescue. Twenty-six patients also received irradiation to the site of primary tumour. The Rapid VAC regimen was well tolerated and largely administered as an out-patient. There was one toxic death which occurred 2 months after high dose melphalan due to a combination of infection and possible anthracycline cardiomyopathy. Stages were, (Intergroup Rhabdomyosarcoma Study (IRS) system) Group, Group II--four patients. Group III--27 patients and Group IV--12 patients; International Society of Paediatric Oncology (SIOP) staging, Stage I--11, Stage II--13, Stage III--7, Stage IV--12. Actuarial survival at 5 years for all stages is 57% and event free survival 44%. For patients with non-metastatic diseases, 62% and 53% respectively. This treatment strategy utilises the philosophy of rapid drug delivery with high dose consolidation and enables all chemotherapy to be finished within a 4 month period. In general, a conservative approach was applied to both radiation and surgery to minimise late sequelae related to these treatment modalities. Although the small number of high risk patients in this study limits conclusions regarding efficacy in these subgroups the overall results with this regimen appear to be comparable to that with other approaches.  相似文献   
7.
High dose melphalan (HDM 110-140 mg/m2) and total body irradiation (TBI, 10.5 Gy, single fraction) followed by infusion of autologous bone marrow (ABMT) was evaluated for toxicity and efficacy in 24 children with acute lymphoblastic leukaemia (ALL) in second (CR2) or third remission (CR3). Marrow was purged with Campath 1 in six children (four were children in CR3). All children had engraftment with a median of 30 days (range 18-70 days) to neutrophil count greater than 0.5 x 10(9)/l. Four children (16%) died from toxicity 1-4 months after autograft, two from pneumonitis, one from an intracerebral haemorrhage and one from sepsis. Apart from fever and mucositis the procedure was well tolerated. Nine of 17 children treated in CR2 remain in complete remission 6-72 months after ABMT (median 25 months). Seven of these have a follow-up of greater than 12 months. Three of the seven children treated in CR3 are alive 17, 22 and 29 months post ABMT. Seven children relapsed within 10 months (median 4 months) of the autograft. Only one relapse has occurred beyond 10 months. HDM and TBI followed by ABMT is a relatively well tolerated regimen and may contribute to survival in children with relapsed ALL.  相似文献   
8.
Previous studies have demonstrated the existence of a large receptor reserve for agonists at somatodendritic 5-hydroxytryptamine1A (5-HT1A) serotonin receptors in the raphe nuclei of the rat. 5-HT1A agonists with anxiolytic properties (e.g., buspirone, gepirone, and ipsapirone) display full intrinsic activity at these receptors but are partial agonists at postsynaptic 5-HT1A receptors, which suggests that the latter sites may be devoid of a receptor reserve. In the present studies, this was directly determined by examining the relationship between receptor occupancy and response at postsynaptic 5-HT1A receptors, in rat hippocampus, mediating the inhibition of forskolin-stimulated adenylyl cyclase activity, using the method of partial irreversible receptor inactivation. Rats were treated with vehicle or the irreversible antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ), and 24 hr later hippocampi were removed for saturation analysis of [3H]8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT) binding to 5-HT1A receptors or for adenylyl cyclase assays. EEDQ (1 and 6 mg/kg) dose-dependently reduced the maximal number of [3H]8-OH-DPAT binding sites by 68.5 and 80%, respectively, without altering the Kd. Concentration-response curves were generated for inhibition of forskolin-stimulated adenylyl cyclase activity by 5-HT and the selective 5-HT1A agonist N,N-dipropyl-5-carboxamidotryptamine (DP-5-CT). EEDQ treatment dose-dependently reduced the maximal inhibitory effect of 5-HT [percentage of inhibition: control, 23.6; EEDQ (1 mg/kg), 13.4; EEDQ (6 mg/kg), 8.9], without altering either the slope factor (1.01) or the EC50 (96.4 nM). Analogous results were obtained with DP-5-CT [percentage of maximal inhibition: control, 24.1; EEDQ (1 mg/kg), 15.2; EEDQ (6 mg/kg), 10.7), again without changes in slope factor (0.89) or EC50 (9.9 nM). Analysis of double-reciprocal plots of equieffective concentrations of agonist, followed by calculation of fractional receptor occupancy, revealed a linear relationship between receptor occupancy and response for both 5-HT and DP-5-CT (i.e., an absence of receptor reserve). The receptor specificity of the effect of EEDQ was demonstrated in two ways. First, it was shown that pretreatment of rats with the selective 5-HT1A partial agonist BMY 7378 (10 mg/kg) before EEDQ afforded substantial protection (about 75%) against loss of the inhibitory effect of DP-5-CT on forskolin-stimulated adenylyl cyclase activity. Second, EEDQ did not alter the inhibition of forskolin-stimulated adenylyl cyclase activity induced by the adenosine A1 receptor agonist phenylisopropyladenosine (PIA).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
9.
18F-FDG PET and PET/CT in fever of unknown origin.   总被引:3,自引:0,他引:3  
Fever of unknown origin (FUO) was originally defined as recurrent fever of 38.3 degrees C or higher, lasting 2-3 wk or longer, and undiagnosed after 1 wk of hospital evaluation. The last criterion has undergone modification and is now generally interpreted as no diagnosis after appropriate inpatient or outpatient evaluation. The 3 major categories that account for most FUOs are infections, malignancies, and noninfectious inflammatory diseases. The diagnostic approach in FUO includes repeated physical investigations and thorough history-taking combined with standardized laboratory tests and simple imaging procedures. Nevertheless, there is a need for more complex or invasive techniques if this strategy fails. This review describes the impact of (18)F-FDG PET in the diagnostic work-up of FUO. (18)F-FDG accumulates in malignant tissues but also at the sites of infection and inflammation and in autoimmune and granulomatous diseases by the overexpression of distinct facultative glucose transporter (GLUT) isotypes (mainly GLUT-1 and GLUT-3) and by an overproduction of glycolytic enzymes in cancer cells and inflammatory cells. The limited data of prospective studies indicate that (18)F-FDG PET has the potential to play a central role as a second-line procedure in the management of patients with FUO. In these studies, the PET scan contributed to the final diagnosis in 25%-69% of the patients. In the category of infectious diseases, a diagnosis of focal abdominal, thoracic, or soft-tissue infection, as well as chronic osteomyelitis, can be made with a high degree of certainty. Negative findings on (18)F-FDG PET essentially rule out orthopedic prosthetic infections. In patients with noninfectious inflammatory diseases, (18)F-FDG PET is of importance in the diagnosis of large-vessel vasculitis and seems to be useful in the visualization of other diseases, such as inflammatory bowel disease, sarcoidosis, and painless subacute thyroiditis. In patients with tumor fever, diseases commonly detected by (18)F-FDG PET include Hodgkin's disease and aggressive non-Hodgkin's lymphoma but also colorectal cancer and sarcoma. (18)F-FDG PET has the potential to replace other imaging techniques in the evaluation of patients with FUO. Compared with labeled white blood cells, (18)F-FDG PET allows diagnosis of a wider spectrum of diseases. Compared with (67)Ga-citrate scanning, (18)F-FDG PET seems to be more sensitive. It is expected that PET/CT technology will further improve the diagnostic impact of (18)F-FDG PET in the context of FUO, as already shown in the oncologic context, mainly by improving the specificity of the method.  相似文献   
10.
Lipopolysaccharide (LPS) preconditioning provides neuroprotection against subsequent cerebral ischemic injury. Tumor necrosis factor-alpha (TNFalpha) is protective in LPS-induced preconditioning yet exacerbates neuronal injury in ischemia. Here, we define dual roles of TNFalpha in LPS-induced ischemic tolerance in a murine model of stroke and in primary neuronal cultures in vitro, and show that the cytotoxic effects of TNFalpha are attenuated by LPS preconditioning. We show that LPS preconditioning significantly increases circulating levels of TNFalpha before middle cerebral artery occlusion in mice and show that TNFalpha is required to establish subsequent neuroprotection against ischemia, as mice lacking TNFalpha are not protected from ischemic injury by LPS preconditioning. After stroke, LPS preconditioned mice have a significant reduction in the levels of TNFalpha (approximately threefold) and the proximal TNFalpha signaling molecules, neuronal TNF-receptor 1 (TNFR1), and TNFR-associated death domain (TRADD). Soluble TNFR1 (s-TNFR1) levels were significantly increased after stroke in LPS-preconditioned mice (approximately 2.5-fold), which may neutralize the effect of TNFalpha and reduce TNFalpha-mediated injury in ischemia. Importantly, LPS-preconditioned mice show marked resistance to brain injury caused by intracerebral administration of exogenous TNFalpha after stroke. We establish an in vitro model of LPS preconditioning in primary cortical neuronal cultures and show that LPS preconditioning causes significant protection against injurious TNFalpha in the setting of ischemia. Our studies suggest that TNFalpha is a twin-edged sword in the setting of stroke: TNFalpha upregulation is needed to establish LPS-induced tolerance before ischemia, whereas suppression of TNFalpha signaling during ischemia confers neuroprotection after LPS preconditioning.  相似文献   
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