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91.
目的探讨急性和慢性呼吸道炎症过程中激肽的生成途径和机制。方法测定支气管肺癌伴阻塞性肺炎,慢性支气管炎和健康对照组支气管肺泡灌洗液(BALF)凝胶过滤前后激肽、激肽形成酶活性(TAMEea),血浆血管舒缓素(PK)和α2巨球蛋白(α2M),并进一步鉴定TAMEea性质。结果急、慢性组TAMEea和激肽水平与健康对照组比较差异有显著性(P<0001,P<0.01),但两组间差异无显著性(P>005);急性组PK和α2M与慢性组比较差异有显著性(P<0001)。凝胶过滤结果显示:急性组BALF的TAMEea最高峰位于分子量约800000处,与第一个α2M峰重叠,而慢性组的最高峰位于40000处。TAMEea抑制试验证实800000处的TAMEea来自于PK;而40000处的TAMEea主要来源于组织血管舒缓素(TK)。结论急性呼吸道炎症的TAMEea主要来自血浆的PK;而慢性呼吸道炎症则以局部组织腺体分泌的TK为主。  相似文献   
92.
There have been publically expressed concerns about the costs and allocation of neonatal and perinatal health care resources in Canada and elsewhere for the past 15 years. This paper reports information from a symposium held during the 1996 Canadian Paediatric Society (CPS) annual meeting sponsored by the CPS Section on Perinatal Medicine. Experts in perinatal epidemiology, health care economics, public policy and finance, and consumer perspectives on the outcomes of neonatal and perinatal intensive care explored the following questions: How should the need for health care resources in the neonatal and perinatal area be objectively determined? When there are competing needs between the maternal-newborn area and other areas, how should these be rationalized? What evidence should be used (or should be available) to support the present use of resources? What evidence should be available (or is needed) to change or introduce new uses of resources? The conclusions indicated that there are no generally accepted methods to determine the allocation of health care resources but that considerations need to include population characteristics, desired outcomes, achievable results, values, ethics, legalities, cost-benefit analyses and political objectives. Information from families and adolescents who required the use of high technology and/or high cost programs will contribute individual, family and societal values that complement cost-efficacy analyses.  相似文献   
93.
自Lane等 1997年详细报道了HSCTGR后 ,一直没有该肿瘤转移潜能的证据 ,该文报道 1例 2 8岁女性右上臂三角肌内HSCTGR(8 7cm× 5 5cm× 4 0cm大小 ) ,术后 4年右肺转移 ,并于 6年后行肺部手术 ,取出 0 6cm~ 1 2cm大小转移性结节 3枚。肿瘤从大体形态到超微结构及免疫组化表现与前文相似。本文总结出该病光镜下由梭形细胞为主 ,构成 3种图像 :①纤维瘤样区 ,为肿瘤的主要成分 ,无核分裂象 ;②细胞区 ,细胞丰富 ,核浓染 ,胶原减少 ,罕见核分裂象 ;③特征性病变 (有诊断意义 ) ,即由丰富细胞核环绕的玻璃样变小体 …  相似文献   
94.
95.

BACKGROUND & PURPOSE

Loperamide is a selective µ opioid receptor agonist acting locally in the gastrointestinal (GI) tract as an effective anti-diarrhoeal but can cause constipation. We tested whether modulating µ opioid receptor agonism with δ opioid receptor antagonism, by combining reference compounds or using a novel compound (‘MuDelta’), could normalize GI motility without constipation.

EXPERIMENTAL APPROACH

MuDelta was characterized in vitro as a potent µ opioid receptor agonist and high-affinity δ opioid receptor antagonist. Reference compounds, MuDelta and loperamide were assessed in the following ex vivo and in vivo experiments: guinea pig intestinal smooth muscle contractility, mouse intestinal epithelial ion transport and upper GI tract transit, entire GI transit or faecal output in novel environment stressed mice, or four weeks after intracolonic mustard oil (post-inflammatory). Colonic δ opioid receptor immunoreactivity was quantified.

KEY RESULTS

δ Opioid receptor antagonism opposed µ opioid receptor agonist inhibition of intestinal contractility and motility. MuDelta reduced intestinal contractility and inhibited neurogenically-mediated secretion. Very low plasma levels of MuDelta were detected after oral administration. Stress up-regulated δ opioid receptor expression in colonic epithelial cells. In stressed mice, MuDelta normalized GI transit and faecal output to control levels over a wide dose range, whereas loperamide had a narrow dose range. MuDelta and loperamide reduced upper GI transit in the post-inflammatory model.

CONCLUSIONS AND IMPLICATIONS

MuDelta normalizes, but does not prevent, perturbed GI transit over a wide dose-range in mice. These data support the subsequent assessment of MuDelta in a clinical phase II trial in patients with diarrhoea-predominant irritable bowel syndrome.  相似文献   
96.
Congenital radioulnar synostosis(CRS) is a rare anomaly and approximately 400 cases were reported worldwide so far. CRS is the failure of the longitudinal segmentation and the persistence of the cartilaginous anlage between the radius and ulna during the seventh week of development that results in a persistent bridge of tissue. Here we are discussing on a case of 25yrs old, male patient with bilateral congenital synostosis. On the left hand the pronation and supination movements are restricted completely where as on right side 10 degree of supination and 20 degree of pronation is possible. Radiologically in our patient synostosis is classified as type II variety by Wilkie(1914)1 classification and type IV by the Cleary and Omer classification(1985). The position of forearm was not found to be related to subjective functional limitation, or employment status. Main line of treatment is surgical mainly rotational osteotomy but is rarely indicated. Our patient is not able to rotate his forearm especially on the left side still he has no functional limitation so he has refused for the operative treatment. No study has objectively compared the preoperative functional limitation of the patients with their postoperative functional improvement in order to justify surgical intervention In the authors opinion the only major factor that is to be taken into consideration of operative treatment is functional limitation to the patient.  相似文献   
97.
Introduction: Amyotrophic lateral sclerosis (ALS), one in a family of age-related neurodegenerative disorders, is marked by predominantly cryptogenic causes, partially elucidated pathophysiology, and elusive treatments. The challenges of ALS are illustrated by two decades of negative drug trials.

Areas covered: In this article, we lay out the current understanding of disease genesis and physiology in relation to drug development in ALS, stressing important accomplishments and gaps in knowledge. We briefly consider clinical ALS, the ongoing search for biomarkers, and the latest in trial design, highlighting major recent and ongoing clinical trials; and we discuss, in a concluding section on future directions, the prion-protein hypothesis of neurodegeneration and what steps can be taken to end the drought that has characterized drug discovery in ALS.

Expert opinion: Age-related neurodegenerative disorders are fast becoming major public health problems for the world’s aging populations. Several agents offer promise in the near-term, but drug development is hampered by an interrelated cycle of obstacles surrounding etiological, physiological, and biomarkers discovery. It is time for the type of government-funded, public-supported offensive on neurodegenerative disease that has been effective in other fields.  相似文献   
98.
This study aimed to explore the therapeutic mechanism of intravenous immunoglobulin (IVIG) for Kawasaki disease (KD). Peripheral blood lymphocytes (PBLs) obtained from 26 children with KD and 20 age-matched healthy children were stimulated with anti-CD3 monoclonal antibody (mAb), and the percentage of apoptotic cells and DNA fragmentation were assayed at 0, 12, 24, 48 and 72 h in vitro. The patients were divided into two groups: one treated with aspirin combined with IVIG (n = 16) and one treated with aspirin alone (n = 10). PBLs were stimulated by phytohaemagglutinin to evaluate the lymphocyte proliferative response. Compared with normal controls, the apoptotic cell percentage and the DNA fragmentation were markedly decreased (p < 0.001) and delayed in PBLs from KD patients. After IVIG treatment, the decreased percentage of apoptotic cell and delayed DNA fragmentation were restored to the state of the normal controls, accompanied by a fast clinical remission compared with the aspirin-alone group. The lymphocyte proliferative response was also decreased 3-5 d after IVIG therapy (p < 0.001). Conclusion: The results suggest that decreased PBL apoptosis may be involved in the pathogenesis of KD. The therapeutic mechanism of IVIG in KD may be partially due to the reversal of the inhibited lymphocyte apoptosis, and may have implications for other autoimmune diseases with inefficient lymphocyte apoptosis.  相似文献   
99.
经皮椎体注入骨水泥治疗老年脊椎骨质疏松压缩性骨折   总被引:4,自引:0,他引:4  
目的:观察经皮椎体内注入骨水泥(聚甲基丙烯酸甲酯)治疗脊椎骨质疏松压缩性骨折的疗效。方法:自2005-06/2006-06吉林大学中日联谊医院骨科及大庆龙南医院骨科对35例40个椎体的骨质疏松压缩性骨折患者使用经皮椎体内注射骨水泥,行椎体成形术。成形材料:美国KYPHON公司生产的骨水泥,生产准许号:(GB/T19001-2000和YY/T0287-1996)。结果:35例患者均参加随访6个月。术后均未出现骨水泥外漏、脊髓或马尾神经损伤等并发症。35例患者中5例出现穿刺部位局部疼痛,服用镇痛药物后均缓解。疼痛完全消失25例,占71.4%;明显缓解8例,占22.6%;轻度缓解2例,占6.0%;无缓解0例。15例患者在术后72h内均能下床活动。术后未再发生压缩性骨折及疼痛。结论:经皮椎体注入骨水泥可以有效改善椎体骨质疏松压缩性骨折患者疼痛症状,随访6个月未出现充填剂不良性宿主反应,临床疗效较好。  相似文献   
100.
The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.  相似文献   
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