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991.
Forty-eight male Wistar rats were exposed to contingent light-shock combinations and 48 rats received light and shock stimuli in a random order. One day after fear conditioning the animals were tested for startle potentation after injection of midazolam (0, 0.5, 1.0, 2.0 mg/kg, IP) or DMCM (methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate; 0, 0.1, 0.2, 0.4 mg/kg IP) or lindane (0, 7.5, 15.0, 30.0 mg/kg PO). Midazolam attenuated potentiated startle dose dependently and the inverse benzodiazepine agonist DMCM had the opposite effect. The effects of lindane on startle amplitudes were identical to those of DMCM, indicating that lindane has anxiogenic effects on behavior. It is suggested that the anxiogenic effects of lindane are mediated by an effect at the GABA-ionophore complex.  相似文献   
992.
The classical triad of sudden devastating chest pain, electrocardiographic absence of acute myocardial Infarction, and Identification of an upstream flap in the ascending aorta by transesophageal echocardlography (TEE) Indicates aortic type A dissection requiring emergent surgery. Among 34 patients presenting with clinical signs and symptoms of an aortic dissection, three did not show the mandatory flap in the upstream aorta. The only echocardlographic finding was aortic wall thickening Indicating an intramural hematoma. Two of these patients showed early aortic ectasia and one showed a pericardial effusion. Despite the missing flap echocardiographlcally, surgery was performed in all three patients. The surgical approach was the same as that for patients with a type A dissection. Two patients are doing well after the procedure, and one patient died after reoperation. The postoperatlve histologic work-up confirmed that there was no intimal tear or dissection of the intimal layer. We conclude that the echocardiographic finding of an Intramural hematoma combined with typical clinical signs of chest pain, with myocardial infarction ruled out, requires emergent surgical intervention. (J Card Surg 1994;9:508–515)  相似文献   
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PURPOSE: In this study, the authors aimed to develop a visual analogue of the widely used Speech Reception Threshold (SRT; R. Plomp & A. M. Mimpen, 1979b) test. The Text Reception Threshold (TRT) test, in which visually presented sentences are masked by a bar pattern, enables the quantification of modality-aspecific variance in speech-in-noise comprehension to obtain more insight into interindividual differences in this ability. METHOD: Using an adaptive procedure similar to the SRT test, the TRT test determines the percentage of unmasked text needed to read 50% of sentences correctly. SRTs in stationary noise (SRT(STAT)), modulated noise (SRT(MOD)), and TRTs were determined for 34 participants with normal hearing, aged 19 to 78 years. RESULTS: The results indicate that about 30% of the variance in SRT(STAT) and SRT(MOD) is shared with variance in TRT, which reflects the shared involvement of a modality-aspecific cognitive or linguistic ability in forming meaningful wholes of fragments of sentences. CONCLUSION: The TRT test, a visual analogue of the SRT test, has been developed to measure the variance in speech-in-noise comprehension associated with modality-aspecific cognitive skills. In future research, normative data of the TRT test should be developed. It would also be interesting to measure TRTs of individuals experiencing difficulties understanding speech.  相似文献   
997.
BACKGROUND AND PURPOSE: Radiation myelopathy is a serious late toxicity after radiotherapy (RT) of metastatic spinal cord compression (MSCC). The risk of myelopathy depends on the equivalent dose in 2-Gy fractions (EQD2). Many radiation oncologists are concerned about spinal Re-RT, because it may result in a high cumulative EQD2. This study investigates effectiveness and feasibility of Re-RT for in-field recurrence of MSCC. PATIENTS AND METHODS: 74 patients, irradiated between 01/1995 and 12/2003 for MSCC, were reirradiated for in-field recurrence of MSCC (Table 1). Primary RT was performed with 1 x 8 Gy (n = 34), 5 x 4 Gy (n = 28), 10 x 3 Gy (n = 4), 15 x 2.5 Gy (n = 4), or 20 x 2 Gy (n = 4). Recurrence occurred after median 6 months (2-40 months). Re-RT was performed with 1 x 8 Gy (n = 35), 5 x 3 Gy (n = 16), 5 x 4 Gy (n = 13), 10 x 2 Gy (n = 4), 12 x 2 Gy (n = 3), or 17 x 1.8 Gy (n = 3). Cumulative EQD2 (alpha/beta = 2 Gy) was 39-40 Gy (n = 21), 49-50 Gy (n = 41), 56-60 Gy (n = 6), or > 60 Gy (n = 6). Follow-up after Re-RT was median 9 months (2-52 months). RESULTS: Re-RT led to an improvement of motor function in 29/74 patients (39%; Figures 1 to 3). On multivariate analysis, outcome was significantly influenced by type of primary tumor (p = 0.013) and by the time of developing motor deficits before Re-RT (p = 0.037), but not by radiation schedule (p = 0.560), by ambulatory status before Re-RT (p = 0.471), by cumulative EQD2 (p = 0.795), nor by the interval between primary RT and Re-RT (p = 0.420; Table 2). Radiation myelopathy was not observed in the whole series. CONCLUSION: Re-RT is an effective treatment for an in-field recurrence of MSCC. After a cumulative EQD2 < or = 50 Gy, radiation myelopathy appears unlikely.  相似文献   
998.
Summary Stereotaxic lesioning of the entorhinal cortex leads to an anterograde axonal degeneration in the molecular layer of the dentate gyrus. As revealed by immunocytochemical and histochemical methods, lesion of the entorhinal cortex induced a proliferation of microglia and an increased expression of established microglial activation markers within the deafferented zone. Reactive microglial cells were detected as early as 24 h after the lesion. The microglial reaction showed a maximum around day 3 post-lesion and disappeared by day 8 post-lesion. Reactive microglia were strongly positive for the B4-isolectin from Griffonia simplicifolia (GSI-B4), expressed high levels of CR3 complement receptor and 5-nucleotidase, but lacked CD4 and MHC class I and II antigens. In addition, microglial cells were identified using MUC 102, a new monoclonal antibody against rat microglia. At the ultrastructural level, reactive microglial cells were consistently seen to phagocytose degenerating terminals. Our data suggest that (1) axonal degeneration represents a sufficient stimulus for inducing microglial activation and proliferation in the deafferented dentate gyrus; (2) these activated microglial cells are characterized by immunophenotypes different from those observed in other types of CNS injury; (3) the early microglial reaction precedes the well-documented astrocyte reaction in the dentate gyrus; and (4) the timed interaction of microglia and astrocytes could be important for regulating regenerative sprouting processes in the mature CNS.  相似文献   
999.
The European Journal of Health Economics - The study objective of this analysis was to determine the cost-effectiveness of vaborem (meropenem-vaborbactam) compared to the best available therapy...  相似文献   
1000.
The lack of consensus over the transition point for the end of the sigmoid and beginning of the rectum is a problem for the colorectal multidisciplinary team. In this review, we survey the wide number of landmarks for the rectosigmoid junction, and describe the theoretical and evidence-based strengths and weaknesses of each one.Without a reliable definition of the rectum, sigmoid and rectal cancers will be classified inconsistently. As the treatment strategies for sigmoid and rectal cancers are radically different, incorrect tumour localisation has a substantial impact on patient management, leading to under or over treatment. Inconsistent classification will confound investigation of metastatic patterns and treatment outcomes. Now that the rectosigmoid junction has been recognised as a distinct segment of colon by the International Classification of Diseases, further heterogeneity in management and outcomes could result to the detriment of patients and research.We describe a bespoke, anatomical and reliable landmark for the rectosigmoid junction; the sigmoid take-off.  相似文献   
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