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81.
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MRI investigation of temporal lobe structures in bipolar patients   总被引:8,自引:0,他引:8  
Previous anatomical MRI studies have suggested abnormalities in amygdala volumes in bipolar disorder, whereas hippocampus, temporal lobe (TL), and superior temporal gyri (STG) measures have been reported to be normal. This study further investigated the existence of anatomical abnormalities in these brain structures in bipolar subjects, to attempt to replicate previously reported findings. Twenty-four DSM-IV bipolar patients (mean age+/-S.D.=35+/-10 years) and 36 healthy controls (mean age+/-S.D.=37+/-10 years) were studied. 3D SPGR images were obtained with a 1.5T-GE Signa magnet (TR=25 ms, TE=5 ms, FOV=24 cm, slice-thickness=1.5 mm, matrix-size=256 x 192). Volumetric measurements of TL, hippocampus, amygdala, and STG were performed blindly, with a semi-automated software. Bipolar patients had significantly larger left amygdala volumes compared with controls (mean volumes+/-S.D.=2.57+/-0.69 vs. 2.17+/-0.58 ml, respectively; ANCOVA, age, gender, ICV as covariates; F=4.42, df=1/55, P=0.04). The volumes of the other temporal lobe structures did not differ significantly between the two groups (ANCOVA, age, gender, and ICV as covariates, P>0.05). Our findings of enlarged left amygdala in bipolar patients are in agreement with prior MRI studies, suggesting that abnormalities in this brain structure may be implicated in pathophysiology of the illness. Longitudinal studies in high-risk offspring and first-episode patients will be needed to examine whether such abnormalities precede the appearance of symptoms, or whether they may appear subsequently as a result of illness course.  相似文献   
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The basal ganglia form a part of the brain neuroanatomic circuits that may be involved in mood regulation. Decreases in basal ganglia volumes have been previously reported in major depressive disorder patients in comparison to healthy controls. In this study, we measured caudate, putamen, and globus pallidus volumes in 25 patients with major depressive disorder (4 M; age+/-S.D.=41+/-11 years) and 48 healthy controls (29 M; age+/-S.D.=35+/-10 years), using high-resolution magnetic resonance imaging (MRI), in an attempt to replicate prior findings. Unlike most previous studies, we did not find significant differences between patient and control groups in basal ganglia volumetric measures. Nonetheless, there was a significant interaction between diagnosis and cerebral hemisphere, with MDD patients showing decreased asymmetry in globus pallidus volumes in comparison with healthy controls. Furthermore, in the patient group, left putamen volumes correlated inversely with length of illness, and left globus pallidus volume correlated directly with number of prior depressive episodes. These findings suggest that abnormalities in lateralization and possibly neurodegenerative changes in basal ganglia structures participate in the pathophysiology of major depressive disorder.  相似文献   
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Slim K 《Annales de chirurgie》2002,127(10):791-793
The conventional laparoscopic access to the gastroesophageal junction involves the retraction the left hepatic lobe upward. This approach could be particularly difficult in obese patients because of a huge fatty liver. The technique described here aims to overcome this difficulty be using a suprahepatic route by displacing the left lobe downward after dividing the left triangular ligament. This approach allows a good exposure of the gastroesophageal junction to perform a fundoplication or a gastric banding.  相似文献   
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The authors report a rare case of juxtacortical osteosarcoma of the radius in a child. The diagnosis and treatment were delayed because of misleading and wrongly reassuring radiological and histological aspects. The 12-year-old boy was admitted for a tumefaction of the proximal extremity of the right radius noticed after trauma. Physical examination showed a hard and slightly painful swelling. Xrays showed an irregular osseous mass developed from the superior metaphysis of the radius and encircling it. MRI showed a juxtacortical tumor with medullary involvement. A biopsy concluded to a fracture callus. Ten months later, the tumor became painful and homogeneous, regular and well defined on Xrays. A repeat biopsy showed juxtacortical osteosarcoma. Enbloc resection of the tumor was done. After a follow-up of 2 years, the child is alive without recurrence and metastasis and with a satisfactory function of the upper limb.  相似文献   
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BACKGROUND: The exact incidence of associated aortic valve incompetence (AVI) and abdominal aortic aneurysm (AAA) in the general population is not known. In recent years, we have observed this association with increasing frequency. This observation is probably due to the extensive preoperative screening of the cardiac and vascular status of patients who are candidates for surgical procedures. The choice of the optimal surgical strategy is needed to achieve low operative morbidity and mortality. The present study reviews our experience with a subset of patients suffering the association of AVI and large AAA. Surgical strategy, clinical management and outcome are presented.METHODS: Between January 1982 and May 2000, 76 patients with the association of AAA and AVI have been evaluated in our institution. Forty-four patients have been treated for both AAA and aortic valve (AV) regurgitation. These patients have been divided into three groups on the basis of the surgical strategy adopted. Group 1: combined procedure (16 patients); group 2: AAA repair prior to AV surgery (nine patients); group 3: AV surgery prior to aneurysm repair (19 patients).RESULTS: Hospital mortality was 4.5% (two patients); overall mortality was 6.8% (three patients).CONCLUSIONS: In patients with AAA and AVI, an accurate and complete preoperative evaluation is essential. Surgical strategy should be individualized on the basis of the cardiac preoperative status.  相似文献   
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PURPOSE: We sought to demonstrate that a single systemic administration of L19mTNFalpha (a fusion protein constituted by the scFv L19 specific for the oncofetal ED-B domain of fibronectin and tumor necrosis factor alpha, TNFalpha) in combination with melphalan induced complete and long-lasting tumor eradication in tumor-bearing mice and triggered the generation of a specific T cell-based immune response that protects the animals from a second tumor challenge, as well as from challenges with syngeneic tumor cells of different histologic origin. Experimental Design and RESULTS: Treatment with L19mTNFalpha, in combination with melphalan, induced complete tumor regression in 83% of BALB/c mice with WEHI-164 fibrosarcoma and 33% of animals with C51 colon carcinoma. All cured mice rejected challenges with the same tumor cells and, in a very high percentage of animals, also rejected challenges with syngeneic tumor cells of different histologic origin. In adoptive immunity transfer experiments, the splenocytes from tumor-cured mice protected naive mice both from C51 colon carcinoma and from WEHI-164 fibrosarcoma. Similar results were also obtained in adoptive immunity transfer experiments using severely immunodepressed mice. Experiments using depleted splenocytes showed that T cells play a major role in tumor rejection. CONCLUSIONS: The results show that the selective targeting of mTNFalpha to the tumor enhances its immunostimulatory properties to the point of generating a therapeutic immune response against different histologically unrelated syngeneic tumors. These findings predicate treatment approaches for cancer patients based on the targeted delivery of TNFalpha to the tumor vasculature.  相似文献   
90.

Background  

Leptin (LEP) has been consistently associated with angiogenesis and tumor growth. Leptin exerts its physiological action through its specific receptor (LEPR). We have investigated whether genetic variations in LEP and LEPR have implications for susceptibility to and prognosis in breast carcinoma.  相似文献   
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