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Age determines memory for face identity and expression   总被引:1,自引:1,他引:0  
Background: The recognition of facial expressions is an important component of emotion processing which contributes to interactional behavior. One of the factors highly associated with potential decline of ability in behavioral tasks is age. Methods: We have investigated age‐related changes in facial identity and expression memory of healthy subjects in three age groups: young adults (20–40 years), elderly adults (60–80 years) and, for the first time in the literature, very old adults (over 80 years of age). Using a picture test, photographs of faces with happy or angry expressions were presented to study participants during the encoding task, and the memory for identity and emotional facial expression was investigated in a subsequent recognition task showing emotionally neutral faces. Half of the faces presented in the recognition task were initially shown in the encoding task. Results: Age interacted with the memory process: the ability to recognize both facial identity and emotional expression declined with advanced age. Happy facial expressions were better recognized in all age groups. Although there was a continuous overall decrease in recognition of both happy and angry expressions with advanced age, the effect favoring happy facial expressions was stable also in very old adults. Other factors such as gender or educational level did not affect the memory process for facial expressions. Conclusions: Our findings suggest that age is a significant determinant of memory for facial identity and emotional expression, and that, similar to younger adults, the recognition process of the elderly favors happy emotional facial expressions.  相似文献   
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We report a case of synchronous olfactory bulb meningioma and undifferentiated carcinoma of the nose and paranasal sinuses that involved and destroyed the anterior skull base and mimicked intracranial invasion by a carcinoma. The heterogeneity of tissue types in the skull base gives rise to a diverse variety of benign and malignant neoplasms which have totally different prognoses. Synchronous development of benign and malignant primary tumors both originating from and involving the skull base at the same location is very rare and may cause confusion for both the skull base surgeon and neuroradiologist.  相似文献   
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Five ileal conduit biopsies, taken after 1-7 years, were examined by light microscopy and scanning electron microscopy. The total height of the lamina mucosa decreased from 700 to 275 microns. The height of the villi diminished from 550 to 50 microns; the depth of the crypts increased from 130 to 244 microns and the villus-crypt index changed from 4.2 to 0.2. Signs of chronic inflammation could be observed. Scanning electron microscopy shows that the number of microvilli per cell was markedly reduced. There was a varied picture of different stages of atrophy. After 3 years microvilli could no longer be observed. In view of the prolonged urinary contamination time, it appears to be imperative to check neobladders with regard to possible carcinoma induction.  相似文献   
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股骨干骨折--逆行穿钉与顺行穿钉的探讨   总被引:1,自引:0,他引:1  
在对股骨骨折进行逆行和顺行置入髓内钉治疗时,两种治疗方法产生很高的愈合率和相近的畸形愈合率。虽然未经过一致的认定,但那些接受顺行穿钉治疗的患者愈合较快。患者在接受逆行穿钉治疗后膝关节疼痛频繁出现,然而髋关节疼痛和异位骨化现象却在接受顺行穿钉治疗的患者中存在。患其它并发症的几率也无显著增长。因此不能决定功能结果。  相似文献   
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The influence of angiotensin II (ANGII) on the dynamic characteristics of renal blood flow (RBF) was studied in conscious dogs by testing the response to a step increase in renal artery pressure (RAP) after a 60 s period of pressure reduction (to 50 mmHg) and by calculating the transfer function between physiological fluctuations in RAP and RBF. During the RAP reduction, renal vascular resistance (RVR) decreased and upon rapid restoration of RAP, RVR returned to baseline with a characteristic time course: within the first 10 s, RVR rose rapidly by 40 % of the initial change (first response, myogenic response). A second rise began after 20–30 s and reached baseline after an overshoot at 40 s (second response, tubuloglomerular feedback (TGF)). Between both responses, RVR rose very slowly (plateau). The transfer function had a low gain below 0.01 Hz (high autoregulatory efficiency) and two corner frequencies at 0.026 Hz (TGF) and at 0.12 Hz (myogenic response). Inhibition of angiotensin converting enzyme (ACE) lowered baseline RVR, but not the minimum RVR at the end of the RAP reduction (autoregulation-independent RVR). Both the first and second response were reduced, but the normalised level of the plateau (balance between myogenic response, TGF and possible slower mechanisms) and the transfer gain below 0.01 Hz were not affected. Infusion of ANGII after ramipril raised baseline RVR above the control condition. The first and second response and the transfer gain at both corner frequencies were slightly augmented, but the normalised level of the plateau was not affected. It is concluded that alterations of plasma ANGII within a physiological range do not modulate the relative contribution of the myogenic response to the overall short-term autoregulation of RBF. Consequently, it appears that ANGII augments not only TGF, but also the myogenic response.  相似文献   
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To determine the time-course of morphological changes after excimer laser treatment of atherosclerotic carotid arteries, laser angioplasty was performed in 34 rabbits after production of an intimal plaque (13 +/- 6 cell layers, 30 +/- 9% stenosis) using electrical stimulations. The animals were sacrificed 3, 7, 14, 21, 28, and 42 days after laser treatment. A total or subtotal thrombotic occlusion was found in four cases. No perforation was observed, but in 10 animals histological examination evidenced a partial ablation of the medial layer with signs of local thrombus formation and local reduction of SMC in the media. In five animals a stenosis of more than 50% of luminal reduction was due to intimal proliferation of smooth muscle cells (SMC), as determined by a monoclonal antibody against alpha-actin. After the initial ablation, a continuous increase of intimal cell layers was found, from 7 +/- 6 cell layers (19 +/- 9% stenosis) at 7 days, to 28 +/- 5 cell layers (45 +/- 18% stenosis) at 28 days following excimer laser angioplasty (p less than 0.01). After 42 days no additional increase of intimal thickening occurred. Our data suggest that incidence and morphology is comparable to the proliferative response of SMC following conventional balloon angioplasty.  相似文献   
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BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress.  相似文献   
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