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101.
Fuller PJ Zumpe ET Chu S Mamers P Burger HG 《The Journal of clinical endocrinology and metabolism》2002,87(3):1395-1401
Granulosa cell tumors of the ovary (GCT) express the inhibin subunit genes and secrete dimeric inhibin. Transgenic mice null for the alpha-inhibin gene develop GCT. It has been suggested that this apparent contradiction may be reconciled if the human GCT are resistant to the tumor-suppressive effects of inhibin. Inhibin receptors have recently been characterized as consisting of either betaglycan or p120 in association with the type II or type I activin receptor subunits (ActR), respectively. To test the hypothesis that GCT may exhibit loss of inhibin receptor expression we have examined the expression of the receptor subunits in a cohort of GCT and in mucinous and serous cystadenocarcinomas and normal ovary. Expression was determined by RT-PCR using gene-specific primers and probes combined with Southern blot analysis of the PCR products. The ActRI subunits and ActRIIA exhibited widespread albeit variable expression across tissues, with the highest levels in the serous tumors. ActRIIB expression was relatively low in the mucinous tumors and high in the GCT. Betaglycan expression was abundant, widespread, and variable across all tissues; highest mean levels occurred in the GCT and normal ovary. p120 expression was low or absent in all tissues except the GCT. Within the GCT there was parallel expression of the ActR subunits, betaglycan and p120; the levels, however, varied considerably between tumors. Expression of betaglycan and p120 in most GCT argues against the hypothesis, but does not exclude the possibility that low or absent expression of p120 might be significant in a subset of these tumors. 相似文献
102.
Lester JF Dojcinov SD Attanoos RL O'Brien CJ Maughan TS Toy ET Poynton CH 《British journal of haematology》2003,123(3):463-468
The All Wales Lymphoma Panel (AWLP) was established in January 1998 to provide a central expert pathological review service for district general hospital pathologists. A discordance rate of 20% between the submitted and reviewed diagnosis has previously been identified. It has not been known whether this change in diagnosis affects clinical management. Ninety-nine patients whose diagnosis was changed as a result of central pathological review are presented. Between January 1998 and August 2000, 125 of 745 (17%) specimens submitted for AWLP review had a consequent change in pathological diagnosis. Of these 125 specimens, 99 (79%) complete case notes were recovered. In all 99 cases, a hypothetical management plan was generated using collected data, clinical protocols and the submitted pathological diagnosis. These plans were compared with the actual management patients received based on the reviewed diagnosis proffered by the AWLP. Forty-six of 99 (46%) cases had a change in management as a result of central pathological review. Overall, management was changed in 8% of cases referred for central pathological review. In conclusion, expert central pathological review has a direct effect on patient management. 相似文献
103.
Segreto HR Ferreira AT Kimura ET Franco M Egami MI Silva MR Segreto RA 《American journal of hematology》2002,71(3):143-151
Experiments were undertaken to assess the role of amifostine in the activation of latent TGFbeta1 and in the smad proteins cascade (smad 2/3, smad4, smad7), focusing on megakaryocytes, in the bone marrow irradiated in vivo. Non-irradiated megakaryocytes were negative for active TGFbeta1. Immunopositivity to active TGFbeta1 was detected in megakaryocytes 10 days after irradiation in amifostine- treated and untreated marrows. Smad 2/3 and smad 4 were strongly positive in the nucleus of megakaryocytes 10 days after irradiation. At the same time, a predominant hypocellular bone marrow with foci of hematopoiesis was observed with few megakaryocytes. An increase in the number of reticulin fibers was also seen. In amifostine-treated marrows, smad 2/3 and smad4 were not detected in the nucleus but were positive in the cytoplasm of megakaryocytes 10 days after irradiation. Coincidentally, bone marrows were cellular with megakaryocytes. Smad7 immunoexpression was detected in the cytoplasm of megakaryocytes in the non-irradiated, amifostine-treated and in the irradiated, amifostine-treated marrows. Data indicate that amifostine does not prevent latent TGFbeta1 activation in irradiated megakaryocytes. While TGFbeta1 signal transduction occurs in megakaryocytes in untreated bone marrows, it is inhibited in megakaryocytes in amifostine-treated marrows due to the induction of smad 7 activation. This is the first report showing smad 7 activation by amifostine. Our results also suggest a role for TGFbeta1 as an inhibitor of megakaryocytes in vivo. 相似文献
104.
Rahel BM Suttorp MJ ten Berg JM Bal ET Ernst SM Rensing BJ Kelder JC Plokker HW 《Journal of interventional cardiology》2004,17(4):197-201
INTRODUCTION: Conventional percutaneous coronary intervention for the treatment of in-stent restenosis (ISR) has shown a high rate of ISR (30-55%). Considering the need for both extrusion of hyperplastic intima and additional stent expansion, a cutting balloon might be more effective for the treatment of ISR. METHODS: We prospectively assessed the immediate and 8-month outcome of balloon angioplasty using the Barath Cutting Balloon in 100 consecutive patients (mean age: 60.5 +/- 10.8 years, 71% male). RESULTS: In 73 lesions (73%), a good result was reached with the cutting balloon only. In 21 lesions (21%) postdilatation and in 6 lesions (6%) predilatation with a conventional balloon was necessary. The mean inflation pressure was 8.7 +/- 2.0 (range: 6.0-18.0) atm. Before the procedure the mean minimal luminal diameter (MLD) was 0.95 +/- 0.45 mm. Quantitative coronary analysis showed a mean diameter stenosis of 65%+/- 16%. Immediately after the procedure the mean MLD was 2.42 +/- 0.54 mm with a mean diameter stenosis of 19%+/- 13%. Two patients died during the follow-up period (1 stroke, 1 nonvascular). At 8-month follow-up 26 patients (26%) reported to have anginal complaints CCS class II-IV of whom 16 (16%) needed target lesion revascularization. CONCLUSION: Treatment of ISR using the Barath Cutting Balloon can be performed safely with good immediate results and a relatively low need for repeated target lesion revascularization at 8-month follow-up. 相似文献
105.
Rapid transition in the structure of a coral reef community: the effects of coral bleaching and physical disturbance 下载免费PDF全文
Ostrander GK Armstrong KM Knobbe ET Gerace D Scully EP 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(10):5297-5302
Coral reef communities are in a state of change throughout their geographical range. Factors contributing to this change include bleaching (the loss of algal symbionts), storm damage, disease, and increasing abundance of macroalgae. An additional factor for Caribbean reefs is the aftereffects of the epizootic that reduced the abundance of the herbivorous sea urchin, Diadema antillarum. Although coral reef communities have undergone phase shifts, there are few studies that document the details of such transitions. We report the results of a 40-month study that documents changes in a Caribbean reef community affected by bleaching, hurricane damage, and an increasing abundance of macroalgae. The study site was in a relatively pristine area of the reef surrounding the island of San Salvador in the Bahamas. Ten transects were sampled every 3-9 months from November 1994 to February 1998. During this period, the corals experienced a massive bleaching event resulting in a significant decline in coral abundance. Algae, especially macroalgae, increased in abundance until they effectively dominated the substrate. The direct impact of Hurricane Lili in October 1996 did not alter the developing community structure and may have facilitated increasing algal abundance. The results of this study document the rapid transition of this reef community from one in which corals and algae were codominant to a community dominated by macroalgae. The relatively brief time period required for this transition illustrates the dynamic nature of reef communities. 相似文献
107.
[目的]了解护理人员的法律意识与自我防护意识,探讨增强护理人员法律意识的对策。[方法]采用自行设计调查表对徐州市4所综合性医院154名护士进行法律意识与自我防护意识的调查。[结果]护士在医嘱执行、病人权利认识、查对制度、护理文件书写、病情危急处理等方面法律意识较强,正确率分别为94.8%,94.2%,93.5%,90.1%,87.7%,但在能否为病人注射自带药品、病人拒绝护理操作时是否记录、护士执业注册的有效期认识、非抢救时间可否执行口头医嘱等方面法律意识薄弱,正确率分别为56.5%,48.0%,40.9%,34.4%;99.4%护士对相关法律知识的需求程度是需要和非常需要,53.3%的护士认为医院对护士法律意识的重视程度是一般重视和不重视。[结论]徐州市护士法律意识整体水平较高,但仍需提高,学校、医院和个人应共同努力,进一步提高护士的法律意识,提升护理服务质量。 相似文献
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110.
We report that angiotensin-converting enzyme (ACE), a critical physiologic regulator of blood pressure, angiogenesis, and inflammation, is a novel marker for identifying hemangioblasts differentiating from human embryonic stem cells (hESC). We demonstrate that ACE+CD45-CD34+/- hemangioblasts are common yolk sac (YS)-like progenitors for not only endothelium but also both primitive and definitive human lymphohematopoietic cells. Thrombopoietin and basic fibroblast growth factor are identified as critical factors for the proliferation of human hemangioblasts. The developmental sequence of human embryoid body hematopoiesis is remarkably congruent to the timeline of normal human YS development, which occurs during weeks 2 to 6 of human gestation. Furthermore, ACE and the renin-angiotensin system (RAS) directly regulate hemangioblast expansion and differentiation via signaling through the angiotensin II receptors AGTR1 and AGTR2. ACE enzymatic activity is required for hemangioblast expansion, and differentiation toward either endothelium or multipotent hematopoietic progenitors is dramatically augmented after manipulation of angiotensin II signaling with either AGTR1- or AGTR2-specific inhibitors. The RAS can therefore be exploited to direct the hematopoietic or endothelial fate of hESC-derived hemangioblasts, thus providing novel opportunities for human tissue engineering. Moreover, the initial events of human hematoendotheliogenesis can be delineated in a manner previously impossible because of inaccessibility to early human embryonic tissues. 相似文献