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41.
Recent discoveries characterizing the molecular basis of lung cancer brought fundamental changes in lung cancer treatment. The authors review the molecular pathogenesis of lung cancer, including genomic abnormalities, targeted therapies, and resistance mechanisms, and discuss lung cancer imaging with novel techniques. Knowledge of the molecular basis of lung cancer is essential for radiologists to properly interpret imaging and assess response to therapy. Quantitative and functional imaging helps assessing the biologic behavior of lung cancer.  相似文献   
42.
Ruptured vertebrobasilar dissecting aneurysm is usually treated surgically because rebleeding negatively affects outcome. However, the risk of rebleeding decreases markedly once several hours have passed from the initial bleeding. Moreover, surgery-related complications are not rare. We describe seven patients with ruptured vertebrobasilar dissecting aneurysm. To prevent rebleeding during the acute stage, we treated all seven patients conservatively with fentanyl instead of emergency surgery. During the follow-up period (mean 20 months), no patient suffered rebleeding. Conservative treatment with fentanyl administration may be a good option for management of ruptured vertebrobasilar dissecting aneurysm during the acute stage.  相似文献   
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Transforaminal lumbar interbody fusion (TLIF) procedure is widely used, but the surgical indications for TLIF in elderly patients remain controversial because of potential risks such as inferior bone quality and higher rate of postoperative complications. Clinical efficacy and operative risk of TLIF in elderly patients are unclear. This study investigated the clinical effect and safety of TLIF for lumbar degenerative spondylolisthesis with radiculopathy or neurogenic claudication in patients aged 70 years or older. The clinical records were retrospectively reviewed of 35 consecutive patients aged 70-86 years (mean 74.8 years) who underwent one or two-level TLIF. The preoperative diagnosis included degenerative spondylolisthesis with segmental instability. Clinical outcomes were assessed by the Japanese Orthopaedic Association score, visual analogue scale, Oswestry Disability Index. Radiological fusion rate was also investigated. Clinical and radiological results were compared with those of 43 younger patients. Clinical outcome measures were significantly improved after operation in the elderly patients, but improvement rates were significantly lower than those of younger patients. Fusion rate was similar in both groups. Overall postoperative complications were increased in aged patients, although the prevalence of complications directly related to surgical technique was not significantly increased. Postoperative complications not related to the surgical procedure were factors affecting poor results. TLIF is acceptable for achieving clinical recovery and lumbar fusion with high radiographic fusion success even in elderly patients, although clinical benefits were limited compared with those of younger patients. Postoperative morbidity was mainly related to general or non-operative site complications.  相似文献   
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PURPOSE: The effect of topical 2% calteolol hydrochloride on the ocular blood flow dynamics in normal human eyes was studied. MATERIALS AND METHODS: Ten healthy volunteers were studied using color Doppler imaging and scanning laser Doppler flowmetry. In the first experiments, one eye received 30 microliters of 2% carteolol hydrochloride twice daily for 7 days and the fellow eye a placebo in a randomized masked manner. The blood flow velocity of the central retinal artery, the ophthalmic artery, and the short posterior ciliary artery, the blood flow volume of the peripapillary retina (PPR), intraocular pressure (IOP), ocular perfusion pressure (OPP) and pulse rate (PR) were measured before treatment, 2 hours after the initial instillation, and after the last instillation on the 7th day. In the control experiments, 30 microliters of placebo was instillated in both eyes, and the above parameters were measured according to the same time schedule as in the first experiments. RESULTS: In the carteolol-treated eyes, the systolic maximum (p = 0.012) and diastolic minimum (p = 0.019) blood flow velocities of the ophthalmic artery, and the blood flow volume of the superior (p = 0.003), central (p = 0.001) and inferior (p = 0.000) PPR showed significant increases in the first experiments compared with the control experiments. IOP and OPP in both eyes showed significant reduction in the first experiments compared with the control study. CONCLUSION: These results indicated that topical carteolol hydrochroride increases the blood flow of the intraorbital microcirculation and PPR.  相似文献   
45.
The frequency, configuration, and distribution of sleep spindles are similar to some of the rhythmic activities seen during task performance. In the present study, the relationship between rhythmic activities during sleep and arithmetic addition was investigated in male university students with (n = 10) and without (n = 10) frontal midline theta activity (Fmtheta). Electroencephalograms (EEGs) during addition in both groups were compared at frontal and central areas on three consecutive days. Polysomnograms were recorded at the same regions on four consecutive nights for each group. The amount of theta rhythm during a mental task (Fmtheta) and in nocturnal sleep at Fz and Cz electrodes was greater for the Fmtheta group than for the non-Fmtheta group, while the amount of beta rhythm at both sites was smaller in the Fmtheta group than in the non-Fmtheta group. There were no differences between the groups in the amount of alpha rhythm at either site. The frequency of alpha rhythm at Fz and Cz in both situations was slower for the Fmtheta group than for the non-Fmtheta group, but there were no differences in the frequency of theta and beta rhythms between the groups at either site. These results suggest that rhythmic activities during a mental task and in sleep may correlate with each other.  相似文献   
46.
The appearance of frontal midline theta activity (Fmθ), recognized as distinct EEG theta rhythm in the frontal midline area during performance of a mental task, reflects feelings of relief from anxiety in humans. In the present study, EEGs were recorded, and the Hamilton Rating Scale for Anxiety and the state anxiety scale of Spielberger's State-Trait Anxiety Inventory were evaluated once a week in 28 patients with generalized anxiety disorder. The Taylor Manifest Anxiety Scale and the trait anxiety scale of Spielberger's State-Trait Anxiety Inventory were used to assess anxiety before and after the tests. The present results suggest that the appearance of Fmθ might be closely related to an improvement in the anxiety symptoms associated with generalized anxiety disorder.  相似文献   
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