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1.
A 65-year-old man developed acute limb ischemia, severe abdominal wall and lower limb livedo reticularis following a coronary angiogram. The differential diagnoses of acute limb ischemia and multiple cholesterol emboli syndrome (MCES) are discussed. This work was performed at Long Island Jewish Medical Center, 270-05, 76th Avenue, New Hyde Park, NY 11040.  相似文献   
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Objective The degree of Left Ventricular Mass Index (LVMI) regression following aortic valve replacement correlates with long-term survival. This study aims to assess the extent of LVMI regression at 3 months following aortic valve replacement (AVR) with different types and sizes of mechanical valves in rheumatic aortic valve disease. Methods The LVMI regression was studied in 34 consecutive patients, undergoing elective AVR for rheumatic aortic stenosis and/or regurgitation. They were grouped in A and B, matched in age, body surface area and pre-operative LVMI, receiving respectively a tilting disc and a bileaflet mechanical valve. The LVMI was calculated by M-mode echocardiography using the Devereux' formula pre-operatively and three months post-operatively. The trend of LVMI reduction was compared between the two groups and amongst the patients with stenotic, regurgitant and mixed aortic valve, pathologies; and receiving different sizes of valves. Results The mean preoperative LVMI was 199g±79.5 g/m2. At three months post aortic valve replacement, the mean LVMI was 130g±49.0 g/m2. There was a significant reduction of LVMI post-operatively (p=0.001) at three months follow-up. The extent of LVMI regression following surgery amongst the groups A and B did not vary significantly (p=0.92). The extent of LVMI regression did not vary significantly in patients with different aortic valve pathology nor with different sizes of the valves implanted. Conclusions There is a significant early LVMI regression following aortic valve replacement in rheumatic aortic valve disease. The type and the size of the mechanical prosthesis or the rheumatic pathology do not appear to influence this regression.  相似文献   
3.
Between November 1988 and February 1992, 416 patients required coronary endarterectomy for diffuse coronary artery disease. This constitutes 16.19 per cent of all patients who underwent coronary artery bypass grafting during the same period. A total of 528 endarterectomies were performed. Four-hundred and twenty-two endarterectomies were performed on right coronary system and 106 endarterectomies were performed on left coronary system. One-hundred and twelve (26.92%) patients required more than one endarterectomies. The hospital mortality was 2.16 percent. 3.37 per cent of patients had perioperative infarction. Intraaortic balloon pump was required in 1.92 per cent of patients. 5.77 per cent of the patients had significant arrhythmias. The patients have been followed up for a mean period of 27 months. One-hundred and forty patients were evaluated by exercise multigated radionuclide angiogram. One-hundred and thirty-four (95.71%) patients showed increase in ejection fraction as compared to preoperative value. Six (4.29%) patients did not show any significant change while eight (5.71%) patients had fall in ejection fraction. Postoperative coronary angiogram was done in 44 patients at a mean of 10 months. 89.59 per cent of grafts to the endarterectomised vessels and 91.67% of grafts to nonendarterectomised vessel were patent. The difference between the two groups was not statistically significant.  相似文献   
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Intradural cavernomas are rare vascular lesions of the spinal cord. Four cases of histologically verified cavernomas of the cord are reported, of which two were extramedullary and two were intramedullary in location. Progressive neurological deficit was the presenting feature in three cases while one patient had a rapid evolution of neurological deficits and was found at surgery to have had bled from the extramedullary lesion. All the patients were subjected to surgery and total excision of the cavernomas was carried out in each case. While two patients improved after surgery the other two remained static. The available literature on spinal cord cavernomas is reviewed.  相似文献   
6.
Leukoerythrophagocytosis by sinus histiocytes in the lymph nodes is a rare cytological observation. Though often seen in lymph nodes draining malignancies, one may occasionally encounter them in vascular lesions. We report a case of leukoerythrophagocytosis by sinus histiocytes of the right supraclavicular lymph nodes in a 35-yr-old male. He presented with a painful soft tissue mass in the right anterior region of the chest wall extending into the axilla of 6 mo duration. Bilateral radial pulsations were absent. The patient had received treatment for pulmonary tuberculosis 1 yr ago. FNAC of the soft tissue mass revealed only blood. Radiological evaluation revealed a vascular lesion, with smooth borders, extending into the upper zone of right lung and displacing the second rib inferiorly. Doppler evaluation confirmed it to be a right subclavian aneurysm with arteritis.  相似文献   
7.
Human immunodeficiency virus type 1 (HIV-1) infection often results in disorders of the central nervous system, including HIV-associated dementia (HAD). It is suspected that tumor necrosis factor-alpha (TNFalpha) released by activated and/or infected macrophages/microglia plays a role in the process of neuronal damage seen in AIDS patients. In light of earlier studies showing that the activation of the insulin-like growth factor I receptor (IGF-IR) exerts a strong neuroprotective effect, we investigated the ability of IGF-I to protect neuronal cells from HIV-infected macrophages. Our results demonstrate that the conditioned medium from HIV-1-infected macrophages, HIV/CM, causes loss of neuronal processes in differentiated PC12 and P19 neurons and that these neurodegenerative effects are associated with the presence of TNFalpha. Furthermore, we demonstrate that IGF-I rescues differentiated neurons from both HIV/CM and TNFalpha-induced damage and that IGF-I-mediated neuroprotection is strongly enhanced by overexpression of the wt IGF-IR cDNA and attenuated by the antisense IGF-IR cDNA. Finally, IGF-I-mediated antiapoptotic pathways are continuously functional in differentiated neurons exposed to HIV/CM and are likely supported by TNFalpha-mediated phosphorylation of I(kappa)B. All together these results suggest that the balance between TNFalpha and IGF-IR signaling pathways may control the extent of neuronal injury in this HIV-related experimental setting.  相似文献   
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A new approach to the automatic extraction of the lumen region and its boundary for gastrointestinal (GI) endoscopic images is presented. First, a quasi region of interest, the darker regions of the image, is segmented using a region splitting scheme termed progressive thresholding. The centre of mass of this segmented region acts as a seed for further processing. Then the lumen region is obtained using a region growing technique called the integrated neighbourhood search (INS). A new quad structure based technique is introduced to enhance the INS speed significantly. A back projection algorithm is suggested to optimise the search for pixels belonging to the lumen region and boundary. A boundary-thinning algorithm is also proposed to remove the redundant pixels from the lumen boundary and to generate a connected single pixel width boundary. The proposed approach does not need a priori knowledge about the image characteristics. The experimental results indicate that the proposed technique enhances the speed of conventional INS by 45.5% to 28.6% based on the lumen size varying from 22,709 pixels to 4947 pixels. The main advantage of the proposed technique is its high-speed response that facilitates real-time analysis of endoscopic images.  相似文献   
10.
Summary The patterns of expression of the human-tumor-associated antigens, CO17-1A, GA73-3, BR55-2, GICA19-9, CA50 and carcino-embryonic antigen (CEA) were studied in the normal colonic mucosa (the last three also in the serum) of Sprague-Dawley rats. Four immunohistochemically different segments were identified: caecum, ascending colon, transverse colon and descending colon. The immunohistochemical reactions of the cells at the lower part of the crypt were essential for the distinction of the four segments. In the caecum, the MAbs 17-1A, 73-3 and 19-9 stained the glycocalyx of the cells of the lower part of the crypts and the Golgi apparatus of the intercalated cells (IC). MAb55-2 stained very weakly the goblet-like cells (GLC) of the lower part of the crypt of transverse colon, in addition to a nearly complete lack of reaction in the upper part of the crypts. In the ascending colon, the lower part of the crypts showed a characteristic diffuse staining of the intercalated cells with MAb55-2. The perinuclear and mucosal staining observed in the GLC of the transverse colon with MAbs 17-1A, 73-3 and 19-9 as against the supranuclear and Golgi zone staining observed in the GLC/goblet cells (GC)/columnar cells (CC) of the lower part of crypts of the descending colon with the same MAbs, distinguished the former segment from the latter. The IC demonstrated by immunohistochemistry in the lower parts of the crypts of caecum and ascending colon appear to correspond to the replicating cells of the colonic crypts.  相似文献   
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