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1.
PURPOSETo evaluate the efficacy, safety, and results of direct thrombolytic therapy in intracranial dural sinus thrombosis by infusion of alteplase (recombinant tissue plasminogen activator).METHODSNine patients were treated during a 2-year period for intracranial dural sinus thrombosis. A microcatheter was placed directly into the thrombus in the dural sinus via the transfemoral route. Thrombolysis was initiated with a rapid injection of 10 mg of alteplase over 10 minutes, followed in 3 hours by a continuous infusion of 50 mg, then a continuous infusion at 5 mg per hour until complete thrombolysis or a total dose of 100 mg per day had been reached. Repeat thrombolysis was tried the following day if complete recanalization did not occur at 100 mg per day.RESULTSSuccessful recanalization with improvement of symptoms was achieved in all cases. Time required for complete thrombolysis was between 8 and 43 hours. The total dose of alteplase ranged from 50 to 300 mg. Complications of a small intrapelvic hemorrhage and oozing at a femoral puncture site occurred in separate cases, but were not related to the amount of infused alteplase. MR venograms obtained 1 to 4 weeks after the procedure showed no evidence of reocclusion of the dural sinuses.CONCLUSIONDirect fibrinolytic therapy with alteplase is safe, fast, and effective in treating dural sinus thrombosis. However, to prevent hemorrhagic complications, further studies are required to determine its optimal dose and proper rate of administration.  相似文献   
2.
This is the first preliminary report among two consecutive papers. Partial mastectomy(PM), axillary lymph node dissection(AD) and radiotherapy (RT) were performed on seventeen operable breast cancer patients who had been admitted from April 1991 to March 1992 to the department of surgery, Yongdong Severance Hospital for improved cosmetic appearance and better survival rate. Of seventeen patients, 47% were T1 lesion and 76% were stage I and II. Extensive intraductal component(EIC) within or around the tumor was also analyzed. Twenty nine per cent of the patients were EIC positive. The mean number of axillary lymph nodes was 21.5 after PM with AD and 20.5 after mastectomy. For radiotherapy, 4,500 rad was delivered to the breast parenchyma and 1,600 rad of boost to the primary tumor site using the electron beam method after surgery. All patients have since been living well without any local recurrence and were satisfied with breast preservation for the one-year follow-up period. We concluded that the PM, AD and RT can be another surgical treatment modality of breast cancer. A longer follow-up data will be followed on the second paper.  相似文献   
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A comparison of 17 narrowly defined borderline patients with 20 nonpatient control subjects indicated that certain individual and combinations of criteria may be more highly correlated with the disorder than others. Requiring any four or certain specific combinations of two or three of the five most discriminating criteria provided the optimal balance of sensitivity, specificity, predictive power, and diagnostic efficiency considerations. Fewer than five DSM-III-R criteria adequately identified the patients.  相似文献   
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Extracellular hydrogen peroxide (H2O2) has been implicated in the activation of phospholipase D (PLD). However, it was still unclear how this activation occurs and what the molecular identity of the H2O2-stimulated PLD isozyme is. This study shows that H2O2 potently increases the PLD activity in mouse lymphocytic leukemic L1210 cells, which contain exclusively PLD2. In addition, H2O2 increased PLD activity only in PLD2-transfected COS-7 cells and not in PLD1-transfected cells. This suggests that PLD2 is selectively activated by H2O2. Depletion of extracellular Ca2+ with EGTA completely blocked the H2O2-induced PLD activation, indicating that Ca2+ influx is required. Moreover, pretreatment of the cells with the protein kinase C (PKC) inhibitors GF-109203X and RO-31-8220 and down-regulation of PKCalpha by prolonged treatment with 4beta-phorbol 12-myristate 13-acetate inhibited the H2O2-stimulated PLD2 activity, which points to the involvement of PKCalpha. Based on these new findings we suggest that PLD2 activity is specifically up-regulated by H2O2 and that the H2O2-induced PLD2 activation is mediated by Ca2+ influx and PKCalpha activation.  相似文献   
8.
We report a case of the unusual location of a cutaneous bronchogenic cyst on the abdominal wall. The patient was a 9-month-old boy who had presented with a 1.5 cm-sized polypoid mass, present since birth. Pathological examination of the excised mass revealed multiple small cystic structures surrounded by the fibroadipose tissue. The lining epithelium consisted of either pseudostratified ciliated columnar epithelium with goblet cells or a single layer of ciliated or non-ciliated cuboidal to columnar cells. The cystic walls contained a well-developed smooth muscle bundle, mucous glands and hyaline cartilage plate. This lesion was adherent to the peritoneum, but there was no direct communication with the abdominal cavity. Cutaneous bronchogenic cyst located in the abdominal wall has not been described in the English literature. The present case suggests a possible origin from a downward migration, from the sequestered bud of a tracheobronchial tree primordium along the midline of the body surface, during embryonic development.  相似文献   
9.
Cell signaling in aging and apoptosis   总被引:9,自引:0,他引:9  
Alterations in apoptotic potential, due to perturbations in cell signaling cascades, could underlie age-related organ-specific cellular degeneration and death. While increased apoptosis could lead to cell loss, as in neuronal degeneration, loss of apoptosis competence might well result in the loss of phenotypic fidelity of somatic cells, which could explain to some extent, the age-related increase in cancer incidence. Results from our laboratory indicate that after subjecting young and old rats to genotoxic stress in the form of methyl methanesulfonate (MMS), an apoptotic response is quickly mounted in the liver of the young animals but virtually absent in the same organ of old animals (Nature Med. 8 (2002) 3). To address the possible molecular signaling defect(s) responsible for the age-related dysfunction of apoptosis in response to MMS, mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases (ERKs), c-Jun NH(2)-terminal kinases (JNKs) and p38 MAPKs, were evaluated in the liver of young and old rats after MMS treatment. The results demonstrated distinct age-specific patterns of MMS-induced MAPKs activation, suggesting that the balance between cell survival and apoptosis after genotoxic stress may be impaired during aging. These results are discussed in terms of the relative importance in aging of biological redundancy, a concept put forward by the late Bernard Strehler, and cellular fidelity.  相似文献   
10.
We have previously shown that activated C1s complement and activated T cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation of desLys58 beta2m. This process can specifically be inhibited by C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed lymphocyte culture (MLC) increased the endogenous production of IL-2 and the generation of allo-specific cytotoxic T lymphocytes. C1-inh was purified from fresh human plasma and added to human or murine MLC and mitogen-stimulated lymphocyte cultures grown in the presence of complement-inactivated serum. Read-outs were cell proliferation, lymphokine production and development of T cell-mediated cytotoxicity. We found that addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte cultures inhibited proliferation, the development of allospecific cytotoxic activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. These data clearly demonstrate a regulatory function of C1-inh on T cell- mediated immune functions.   相似文献   
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