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51.
52.
Selective heparanase localization in malignant melanoma   总被引:3,自引:0,他引:3  
Heparanase (HPSE-1) is an endo-beta-D-glucuronidase that cleaves heparan sulfate proteoglycans (HSPG), and its expression has been associated with increased growth, metastasis, and angiogenesis of tumors. Since metastatic melanoma cells express high levels of HSPG and because melanoma tumors grow highly vascularized, we analyzed melanoma tissue specimens for HPSE-1 expression from experimental animals as well as from patients. Laser capture microdissection microscopy was used to extract melanoma cell populations and to isolate them from adjacent tissue. In experimental animals, a 29-fold upregulation of HPSE-1 expression was detected by real-time PCR in metastatic melanoma compared to normal lung tissue. Additionally, immunohistochemistry (IHC) revealed selective HPSE-1 staining in human metastatic melanoma when compared to primary melanoma tumors from the same patient. IHC also showed a marked staining for the enzyme around blood vessels and in vascularized regions. Our results provide evidence demonstrating that HPSE-1 likely plays important roles in regulating the in vivo growth and progression of melanoma. These results further emphasize the importance that therapies designed to block HPSE-1 activity may aid in controlling this type of cancer.  相似文献   
53.
Tissue factor (TF), the initiator of coagulation, continuously circulates in the plasma, and the clotting system "idles," generating very low levels of active clotting enzymes, clotting products, and by-products. Given the enormous amplification potential of the clotting cascade, rigorous control is required to ensure that such low-level stimulation does not cause massive system amplification and response. We propose that among the various mechanisms of regulation, activation thresholds may play a major role. These arise when positive-feedback reactions, of which there are several in the clotting system, are regulated by inhibitors. Such thresholds act like switches, so that small stimuli and/or nonproductive local conditions will generate no response, whereas larger stimuli or the existence of local prothrombotic conditions will produce a full, explosive response. We review here the evidence for system idling, the structures of the various feedback mechanisms of clotting, the mechanisms by which they can produce threshold behavior, and the possible role of thresholds in system regulation.  相似文献   
54.
Computed tomography of abdominal fatty masses   总被引:2,自引:0,他引:2  
  相似文献   
55.
56.
Presenilin 1 and 2 are 2 highly homologous genes involved in familial Alzheimer disease. While more than 100 mutations in presenilin 1 are known to segregate with the disease in familial Alzheimer disease, only 9 mutations of presenilin 2 have been identified to date. We report the clinical and neuropathological phenotype of FLO10, the large Italian Alzheimer kindred associated with methionine to valine substitution at residue 239 of presenilin 2. The patients showed a remarkable variability in age of onset of symptoms, disease duration, and clinical presentation. The neuropathological study of 2 patients revealed peculiar features in addition to neurofibrillary changes and A beta amyloid deposits in the neuropil and vessel wall. Ectopic neurons in the subcortical white matter, often containing neurofibrillary tangles, were found in both patients, one of whom presented with epilepsy. Furthermore, 1 patient showed an unusually high number of ghost tangles in the cerebral cortex. These observations indicate that the Alzheimer kindred FLO10 associated with M239V mutation of presenilin 2 is characterized by some peculiarities of the clinical and neuropathologic phenotype compared to sporadic Alzheimer disease.  相似文献   
57.

Background  

We describe a patient who underwent transurethral resection of the prostate for urinary obstructive symptoms and had histological findings of adenocarcinoma of the prostate with prostatic localization of chronic lymphocitic leukemia (CLL).The contemporary presence of CLL, adenocarcinoma of the prostate and residual prostatic gland after transurethral resection has never been reported before and the authors illustrate how they managed this unusual patient.  相似文献   
58.
BACKGROUND: Oral and topical mesalazine formulations are effective in active ulcerative colitis, but little is known on the efficacy of combined treatment. AIM: To compare the efficacy of oral mesalazine vs. combined oral and topical mesalazine in mildly to moderately active ulcerative colitis. METHODS: Patients with mildly to moderately active ulcerative colitis (Clinical Activity Index, CAI 4-12) were identified at 15 participating centres. They were randomized to receive either mesalazine 4 g orally plus placebo enema, or mesalazine 2 g orally plus mesalazine 2 g rectally as a liquid enema for 6 weeks. The rate of clinical remission (CAI < 4) or clinical remission/improvement (reduction of CAI of 50% from baseline) at 6 weeks and time to clinical remission/improvement were primary end-points; the rate of endoscopic remission was a secondary end-point. RESULTS: 67 patients were assigned to oral treatment and 63 to combined treatment. One patient in the oral group and 2 in the combined group discontinued the treatment due to adverse events. Following an intention-to-treat analysis, the rate of clinical remission was 82% for oral treatment and 87% for combined treatment (P=0.56); the mean time to remission 22.2 and 20.2 days, respectively (P=0.29); the rate of clinical remission/improvement and the rate of endoscopic remission were 85% and 91% (P=0.503) and 58% and 71% (P=0.21), respectively. CONCLUSIONS: In patients with mild active ulcerative colitis, mesalazine 4 g orally and 2 g orally plus 2 g enema are equally effective in inducing disease remission.  相似文献   
59.
We report one case of leiomyosarcoma (LMS) of the larynx occurring in a patient with a history of immunosuppressive therapy, and offer a critical review of the literature. Epstein-Barr virus (EBV) genome was not identified in the neoplastic cells. The patient was treated with endoscopic resection and post-operative radiotherapy. Lung metastasis and thyroid infiltration became evident 14 months following treatment despite the absence of laryngeal recurrence. Progressive decline occurred and the patient died 15 months after diagnosis.  相似文献   
60.
In an infant with Menkes's steely-hair syndrome, early treatment (from 21 days of age) with parenteral copper failed to halt the disease. In addition to urinary tract abnormalities, panlobular emphysema was present a finding not previously noted in the syndrome.  相似文献   
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