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61.
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension.  相似文献   
62.
Smoking and raven IQ   总被引:1,自引:0,他引:1  
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks.  相似文献   
63.
Sharon Gohari  BS    Charles Gambla  MD    Mary Healey  RN    Gail Spaulding  RN    Kenneth B. Gordon  MD    James Swan  MD    Brian Cook  MD    Dennis P. West  PhD    Jean-Christophe Lapiere  MD 《Dermatologic surgery》2002,28(12):1107-1114
BACKGROUND: Human Skin Substitute (Apligraf, Organogenesis, Inc., Canton, MA) is a bi-layered tissue-engineered living biological dressing developed from neonatal foreskin. It consists of a bovine collagen matrix containing human fibroblasts with an overlying sheet of stratified human epithelium containing living human keratinocytes. Human Skin Substitute (HSS) appears to be immunologically inert, and has shown usefulness in the treatment of chronic and acute wounds. OBJECTIVE: Primary objectives were to evaluate the safety and efficacy of HSS in the treatment of full-thickness wounds in a prospective case series. Secondary objectives were to determine the rate of complete wound reepithelialization, incidence of complete wound healing, pain at wound site, overall cosmetic outcome, and patient satisfaction. METHODS: Fourteen patients were enrolled in the study, of which 12 were evaluable. HSS was applied in a blinded fashion to 6 of the patients immediately following Mohs or excisional surgery for skin cancer. The remaining 6 patients were allowed to heal by secondary intention. Both groups were evaluated at weekly appointments until complete reepithelialization occurred. During each evaluation, wound quality was assessed through the Vancouver Burn Scar Assessment Scale by the investigator and an independent blinded dermatologist. The investigator, blinded observer, and patient further evaluated the cosmetic outcome of the wound through the use of a Visual Analog Scale over a 6-month period. RESULTS: HSS patients and secondary intention patients were equivalent in comorbid factors such as pain, erythema, edema, exudate, infection, or hematoma between the groups. The incidence of complete wound healing at 6 months was 100% for both groups. Both groups also appeared to heal at similar rates, as defined by the complete reepithelialization of the wound. HSS patients ultimately resulted in more pliable and less vascular wounds as defined by the Vancouver Burn Scar Assessment Scale. Patient satisfaction with cosmetic outcome in both groups was positive at 6 months. CONCLUSIONS: HSS appears to be a safe, well-tolerated biological dressing with equivalent comorbid factors to secondary intention healing. HSS, however, seems to produce a more pliable and less vascular scar than those developed through healing by secondary intention. HSS also appears to produce more satisfactory cosmetic results when compared to secondary intention healing.  相似文献   
64.
Mechanism of long-term degeneration of arterialized vein grafts   总被引:3,自引:0,他引:3  
This study examined long-term changes in the morphology and cellular kinetics of rabbit vein grafts transplanted into the carotid artery. Six grafts were studied 1 year after implantation. Although the circumference and thickness of the wall were not different than at 12 weeks, degenerative changes occurred. The endothelial lining of the graft appeared intact, but large segments of the graft surface no longer excluded Evans blue dye, suggesting increased permeability. Collections of red blood cells were noted within the intima. Several grafts had extensive subendothelial fibrin deposits, often associated with foam cells, and evidence of previous hemorrhage, but these changes did not stimulate significant smooth muscle cell proliferation. Increased permeability with entrance of proteins and erythrocytes into the intima may result from increased wall tension or from low shear rates at the wall. Similar changes may lead to atherosclerosis in human vein grafts at late times.  相似文献   
65.
Summary Unresectable solid tumors in the metastatic stage are quite resistant to current chemotherapy and radiation therapy regimens. Flavone acetic acid (FAA) is a novel antitumor agent which appears to work through a different mechanism than the conventional chemotherapeutic agents. In preclinical studies it has shown effectiveness against a variety of transplantable murine and human tumors and appears to be solid tumor selective. It also has non-overlapping toxicities as compared to conventional agents. We therefore investigated FAA in vitro against human colon cancer cells and explored whether its effectiveness could be enhanced in combination with other agents such as adriamycin (ADR), cis-platinum (CP) and difluoromethyornithine (DFMO) — an inhibitor of polyamine biosynthesis. Addition of FAA for 24 hours in liquid media produced dose dependent growth inhibition. Using soft agar colony assay, growth was inhibited by 58% by 3mM FAA and only 1.4% by 0.375mM FAA. The combination of FAA and cis-platinum produced synergism at the lower doses tested. The combination of FAA and adriamycin produced antagonism at all doses tested and the combination of FAA with DFMO did not produce results significantly different from DFMO alone. We conclude that enhancement of FAA activity can be achieved in combination with conventional antitumor agents, but may be drug and dose specific.  相似文献   
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68.
This paper, written by two male nurse teachers, describes and analyses their experience of working in a nurse education culture permeated by the philosophy of business management The introduction of business management practices to nurse education is discussed as a reflection of the current political hegemony of market forces and individualism The authors discuss the implications for nurse teachers of being continually exposed to these politically motivated forces which increasingly provide the paradigm for service developments within the United Kingdom health services In discussing the impact of this exposure it is argued that at the personal level individual teachers are experiencing a degree of apathy and personal dissonance which undermines their professional value system, resulting in emotional distress and a crisis of identity It provides a critical reflection on the way organizational dynamics and power relations influence the subjective sense-making of individuals The authors use a multiplicity of perspectives, including those provided by individual psychology, power relations, feminism and personhood, to argue for the need to develop an alternative paradigm which is characterized by the valuing of individual persons, empathic sensitivity and the fostering of creativity been important to us from a personal and professional  相似文献   
69.
经皮穿刺椎体成形术治疗合并肺气肿的胸椎压缩性骨折   总被引:1,自引:0,他引:1  
目的 探讨合并严重肺气肿的胸椎压缩性骨折进行经皮穿刺椎体成形术的技术特点和治疗效果。方法 7例(10个椎体)合并严重肺气肿并且透视椎体显示不清的胸椎骨质疏松椎体压缩骨折患,侧卧位在CT结合C型臂透视引导下进行经皮穿刺椎体成形术。术前、术后2d和随访时分别测定疼痛强度评分、止痛药使用和活动能力评分。随访2-8个月,平均5个月。结果 7例皆顺利完成手术,注射骨水泥的量平均2.2ml/椎体(1.0~4.0m1),无临床并发症,手术时间2—3.5h/例。疼痛强度评分值术后2d比术前平均减低3.9,随访时进一步下降0.2—2.9,活动能力和止痛药使用术后均明显改善。结论 合并肺气肿的胸椎压缩性骨折患行经皮穿刺椎体成形术治疗前应进行骨折椎体透视检查,显示不清选择侧卧位在CT结合C型臂透视引导下穿刺注射可获得良好疗效。  相似文献   
70.
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