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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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OBJECTIVES: Endoscopic sinus surgery (ESS) is considered to be the golden standard for surgery in patients with chronic rhinosinusitis and nasal polyposis. However, there is still a small group of patients unresponsive despite repetitive surgery. Radical surgery aimed at reduction of the inflammatory burden and optimization of drainage of the sinuses has been suggested as a last resort for these patients. STUDY DESIGN: A prospective, questionnaire-based study was conducted in a group of 23 patients who underwent Denker's procedure for refractory chronic rhinosinusitis. Symptoms were evaluated before Denker's procedure and 12 months and 2 years after surgery. RESULTS: Patients reported improvement of feelings of congestion in 74%, rhinorrhea in 70%, and nasal obstruction in 60% of the cases. The following postoperative improvements were statistically significant: rhinorrhea (P = 0.001), feelings of congestion (P = 0.02), and nasal obstruction (P = 0.03). Reduced olfactory perception and asthma did not improve. CONCLUSION: Radical surgery may be a viable treatment option in case of recurrent ESS failure. EBM rating: C-4.  相似文献   
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The chlorinating activity of myeloperoxidase, isolated from human polymorphonuclear neutrophils, was inhibited by the non-steroidal anti-inflammatory drug diclofenac (Voltaren). The concentration of diclofenac needed for 50% inhibition was 20 microM, a value comparable with IC50 values found for other drugs. Diclofenac did not react with HOCl nor with H2O2 but was oxidized in the presence of myeloperoxidase and H2O2 to an orange-coloured unstable product. The rate of oxidation was proportional to the enzyme concentration and to the concentration of diclofenac. but independent of the H2O2 concentration. Presumably both Compound I and Compound II, two intermediates formed during the reaction cycle of myeloperoxidase with H2O2 are able to oxidize diclofenac. In these redox reactions, the active short-living Compound I is reduced to Compound II, thereby inhibiting the chlorinating activity of the enzyme. Analysis by Fast Atom Bombardment mass spectrometry showed that in the presence of H2O2 myeloperoxidase oxidizes diclofenac to dihydroxyazobenzene.  相似文献   
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Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
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Impact of clinical history on fracture detection with radiography   总被引:3,自引:0,他引:3  
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information.  相似文献   
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王文杰  朱秀媛 《药学学报》1989,24(2):151-154
Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice.  相似文献   
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Background  

There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015.  相似文献   
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