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排序方式: 共有2115条查询结果,搜索用时 15 毫秒
1.
Neetu Radhakrishnan M.D. Chong. H. Park M.D. Barry M. Kaplan M.D. F.A.C.C. Rajiv Jauhar M.D. F.A.C.C. 《The International journal of angiology》2006,15(1):37-42
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
2.
Caroline Bolton-Smith Marion E T McMurdo Colin R Paterson Patricia A Mole Julia M Harvey Steven T Fenton Celia J Prynne Gita D Mishra Martin J Shearer 《Journal of bone and mineral research》2007,22(4):509-519
Dietary supplementation with vitamin K(1), with vitamin D(3) and calcium or their combination, was examined in healthy older women during a 2-year, double-blind, placebo-controlled trial. Combined vitamin K with vitamin D plus calcium was associated with a modest but significant increase in BMC at the ultradistal radius but not at other sites in the hip or radius. INTRODUCTION: The putative beneficial role of high dietary vitamin K(1) (phylloquinone) on BMD and the possibility of interactive benefits with vitamin D were studied in a 2-year double-blind, placebo-controlled trial in healthy Scottish women > or =60 years of age. MATERIALS AND METHODS: Healthy, nonosteoporotic women (n = 244) were randomized to receive either (1) placebo, (2) 200 microg/day vitamin K(1), (3) 10 microg (400 IU) vitamin D(3) plus 1000 mg calcium/day, or (4) combined vitamins K(1) and D(3) plus calcium. Baseline and 6-month measurements included DXA bone mineral scans of the hip and wrist, markers of bone turnover, and vitamin status. Supplementation effects were tested using multivariate general linear modeling, with full adjustment for baseline and potential confounding variables. RESULTS: Significant bone mineral loss was seen only at the mid-distal radius but with no significant difference between groups. However, women who took combined vitamin K and vitamin D plus calcium showed a significant and sustained increase in both BMD and BMC at the site of the ultradistal radius. Serum status indicators responded significantly to respective supplementation with vitamins K and D. Over 2 years, serum vitamin K(1) increased by 157% (p < 0.001), the percentage of undercarboxylated osteocalcin (%GluOC) decreased by 51% (p < 0.001), serum 25-hydroxyvitamin D [25(OH)D] increased by 17% (p < 0.001), and PTH decreased by 11% (p = 0.049). CONCLUSIONS: These results provide evidence of a modest synergy in healthy older women from nutritionally relevant intakes of vitamin K(1) together with supplements of calcium plus moderate vitamin D(3) to enhance BMC at the ultradistal radius, a site consisting of principally trabecular bone. The substantial increase in gamma-carboxylation of osteocalcin by vitamin K may have long-term benefits and is potentially achievable by increased dietary intakes of vitamin K rather than by supplementation. 相似文献
3.
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
4.
5.
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
6.
Pleural effusion is a common diagnostic problem. The analysis of serum and pleural fluid for tumour markers is widely used as a diagnostic aid in clinical practice. The aim of the present study was to determine the usefulness of simultaneous quantification of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA-125) in distinction of malignant from benign effusion. Data from a total of 78 patients including 53 patients with benign and 25 patients with malignant effusion was evaluated. The cut-off values for differentiating benign from malignant effusions were determined using results obtained from patients with known benign effusions (mean + 2 SD, 95% confidence interval). The cut-off for CEA and CA-125 were 5.1 ng/ml and 1707 IU/ml respectively. CEA assay in pleural fluid had an acceptable sensitivity and good specificity of 64% and 98% respectively. CA-125 had a sensitivity of 36% and specificity of 94%. The combination of the two tumour markers gave a sensitivity of 72% and specificity of 92.4%. We suggest a good clinical strategy may be to begin with CEA measurement (assay specificity 98%); if CEA is below the cut-off value (negative), CA-125 could then be measured to improve the sensitivity of detection of malignant effusions. However, measurement of these tumour markers is not cost effective from the point of view that it does not give information on the type of malignancy present. The latter has to be determined either by histological or cytological study. 相似文献
7.
Neuroprotective effects of IGF-I against TNFalpha-induced neuronal damage in HIV-associated dementia
Ying Wang J Peruzzi F Lassak A Del Valle L Radhakrishnan S Rappaport J Khalili K Amini S Reiss K 《Virology》2003,305(1):66-76
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
8.
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
9.
Gita Ramjee Robin Shattock Sinead Delany Ian McGowan Neetha Morar Megan Gottemoeller 《AIDS research and therapy》2006,3(1):25-10
Current HIV/AIDS statistics show that women account for almost 60% of HIV infections in Sub-Saharan Africa. HIV prevention
tools such as male and female condoms, abstinence and monogamy are not always feasible options for women due to various socio-economic
and cultural factors. Microbicides are products designed to be inserted in the vagina or rectum prior to sex to prevent HIV
acquisition. 相似文献
10.
Fine-needle aspiration cytology of phyllodes tumors 总被引:3,自引:0,他引:3
Breast lesions with a significant spindle cell or mesenchymal component are not commonly encountered in fine-needle aspiration (FNA) cytologic material and include a heterologous variety of benign and malignant conditions, with phyllodes tumors (PTs) being the foremost differential diagnostic consideration. This study comprises 28 tumors diagnosed histologically as PT in which FNAC material was available for review. Histological sections and cytological smears from these cases were retrieved and subjected to detailed morphological review. Cytological parameters assessed included ratio of stroma to epithelium, pattern characteristics and cytological characteristics of the stromal, and epithelial components and the background cells. Large and hypercellular stroma fragments, dissociated spindle and plump stromal cells, often accompanied by large, folded sheets of epithelium were cytological features that characterized PT. Smears from malignant PT showed predominantly or solely mesenchymal components. FNAC was a highly reliable procedure for the diagnosis of PT, giving an accuracy rate of 92.8%. 相似文献