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An unusual case of heteropagus twinning.   总被引:1,自引:0,他引:1  
A 3-day-old boy baby presented with a cystic umbilical swelling covered mostly by skin and partly by amnion. On the surface, an early embryo-like structure was attached (facial features and limb buds). The deeper aspect of it was composed of large cystic and tubular structures and solid organs resembling liver and spleen. It was labeled as acardiac amorphous parasitic twin, the first of its kind to be reported.  相似文献   
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PURPOSE: In a neonatal rat model of hypoxic-ischemic (HI) brain injury, using T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI), we aim to determine the best MRI method of lesion quantification that reflects infarct size. MATERIALS AND METHODS: Twenty 7-day-old rats underwent MRI 24h after HI brain injury was induced. Lesion size relative to whole brain was measured using T2WI and apparent diffusion coefficient (ADC) maps, applying thresholds of 60%, 70% and 80% contralateral control hemisphere mean ADC, and at day 10 post-HI on pathology with TTC staining. Multiple linear regression analysis was used to study the relationships between lesion size at MRI and pathology. RESULTS: Lesion size measurement using all MRI methods significantly correlated with infarct size at pathology; using T2WI, r=0.808 (p<0.001), using 80% ADC, 70% ADC and 60% ADC thresholds, r=0.888 (p<0.001), 0.761, (p<0.001) and 0.569 (p=0.014), respectively. Eighty percent ADC threshold was found to be the only significant independent predictor of final infarct volume (adjusted R(2)=0.775). CONCLUSION: At 24h post-HI, lesion size on DWI, using 80% ADC threshold is the best predictor of final infarct volume. Although T2WI performed less well, it has the advantage of superior spatial resolution and is technically less demanding. These are important considerations for experiments which utilize MRI as a surrogate method for lesion quantification in the neonatal rat HI model.  相似文献   
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Summary: The involvement of the IgA immune system and complement components in IgA glomerulonephritis (IgAGN) has prompted the use of immunosuppressive drugs in therapy, but none has so far been shown to alter the natural course of the disease. Because most patients with IgAGN present during the chronic phase of their illness, at the time when the initiating immune events may no longer be active, nonimmune therapy which targets the common pathway of progressive renal injury is likely to be more useful. There is increasing evidence that angiotensin-converting enzyme inhibitors (ACEI) reduce proteinuria and renal injury in patients with IgAGN, and this effect may be observed in both normotensive and hypertensive patients. Yet to be determined is whether this effect is specific for ACEI and whatever other effective antihypertensive drugs may achieve a similar result. Fish oil has recently been shown to retard the progression of renal failure in patients with aggressive IgAGN, but a narrow therapeutic window appears to exist for this form of treatment. Antiplatelet agents on their own appear to be ineffective but in combination with anticoagulation (low dose warfarin) have been shown to have an antiproteinuric effect and may preserve renal function in patients with progressive disease. Future directions of non-immune therapy of IgAGN include evaluation of the renoprotective effect of angiotensin II receptor antagonists, free-radical scavengers and antilipid drugs. More work should also be done to identify factors which put the patients at risk of developing progressive disease and which predict therapeutic response, as has been done recently with the identification of the deletion polymorphism of the angiotensin-converting enzyme gene as a marker of progressive disease and therapeutic response to ACEI in patients with IgAGN.  相似文献   
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Recently, we and others showed that the components of green tea may be useful cancer chemopreventive agents. It has been suggested that (-)-epigallocatechin-3-gallate (EGCG), the major constituent in green tea, may possess antitumor-promoting and/or anticarcinogenic effects in rodent tumor bioassay systems. During the chemical analysis of various green tea products, we found a traditionally preserved preparation of green tea used by tribes in the Himalayan region of Sikkim, India that was rich in EGCG. EGCG was isolated from this tea product, and its inhibitory effects were evaluated against the binding of topically applied 3H-labeled polycyclic aromatic hydrocarbons (PAHs) to epidermal DNA and 12-O-tetradecanoylphorbol-13-acetate (TPA) caused induction of epidermal ornithine decarboxylase (ODC) activity in Sencar mice, the short-term markers of tumor initiation and tumor promotion, respectively. Preapplication of EGCG resulted in significant inhibition (p less than 0.05) in the binding of [3H]PAH to epidermal DNA. Similarly, the topical application of EGCG resulted in significant inhibition (p less than 0.005) in TPA-caused induction of epidermal ODC activity. In further studies, we assessed the anti-skin tumor-initiating effect of EGCG in Sencar mice in an initiation-promotion protocol. The application of EGCG before challenge with 7,12-dimethylbenz[a]anthracene as tumor initiator resulted in significant reduction both in percentage of mice with tumors and number of tumors per mouse compared with a non-EGCG-pretreated group of animals. The results of the present study suggest that the green tea preparation from Sikkim may be a good source for the isolation of EGCG and that this compound may have significant potential as a cancer chemopreventive agent.  相似文献   
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Cauda equina nerve sheath tumors are usually small, well-encapsulated tumors. Sometimes they may attain very large proportions, cause extensive bony changes, and resemble ependymomas in the cauda equina. They may also infiltrate into adjacent soft tissue planes and retroperitoneal spaces and yet be histologically benign. An awareness of this entity ensures aggressive surgical removal at the time of exploration. Primary neuro-fibrosarcomas or malignant changes in primary nerve sheath tumors of the cauda equina are seen in patients with neurofibromatosis.  相似文献   
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Four meanings of medical necessity have emerged, evolved, and dominated past and current health policy debates about the appropriate level of service coverage under Canada's health insurance program. To explore the shift in definition, provincial government and national health care association position papers responding to federal legislative and policy reviews of Canada's health insurance program from 1957 to 1984 were examined, as were more current reports on medical necessity. Four meanings of medical necessity predominated: "what doctors and hospitals do"; "the maximum we can afford"; "what is scientifically justified"; and "what is consistently funded across all provinces." These meanings changed with time as different stakeholder associations and governments redefined the concept of medical necessity to achieve different policy objectives for health service coverage under Canada's health insurance program.  相似文献   
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Jones D  Bhatia VK  Krausz T  Pinkus GS 《Human pathology》1999,30(12):1441-1448
Intracellular immunoglobulin crystal formation within plasma cells is an uncommon finding in multiple myeloma and other lymphoplasmacytic tumors. We present 12 cases of plasmacytic tumors with prominent crystal formation, including myeloma (5 cases), lymphoplasmacytic lymphoma (6 cases), and a nonneoplastic plasma cell proliferation. In all cases, crystal formation was associated with the proliferation of variable numbers of histiocytes containing similar inclusions. These cases showed a variety of appearances, sometimes obscuring the underlying plasma cell tumor and raising the differential diagnosis of a storage disorder, hemophagocytosis, or a mesenchymal lesion. In cases of lymphoplasmacytic lymphoma, patients typically presented with marked paraproteinemia and symptoms of hyperviscosity. Crystal-storing histiocytosis was not associated with other immunoglobulin deposition disorders, including amyloidosis, Mott cell tumors, or kappa-light chain deposition. In our cases and those previously reported, we found an overwhelming association of crystal-storing histiocytosis (CSH) with tumors expressing immunoglobulin kappa light chain with no consistent association with a particular heavy chain. These results suggest that CSH results from the ingestion of crystals produced by plasma cell tumors that either overproduce kappa light chain or express a structurally aberrant molecule. CSH persists in the marrow and other sites throughout the course of the disease and in our series was not highly associated with development of the adult Fanconi syndrome or rapid clinical deterioration.  相似文献   
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