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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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OBJECTIVE: To determine the mortality of a population of patients diagnosed with Charcot neuropathic osteoarthropathy managed by a single specialist unit and to compare the results with a control population. METHODS: We have undertaken a retrospective analysis of all cases of Charcot foot on the comprehensive database which has been maintained at the specialist diabetic foot clinic at the City Hospital, Nottingham since 1982. Survival and the incidence of amputation (major and minor) was compared with a control population referred with uncomplicated neuropathic ulceration. Controls were individually matched for gender, age (+/-2 years), disease type, disease duration (+/-2 years) and year of referral (+/-3 years). RESULTS: Forty-seven cases (21 female, 26 male) of Charcot foot were identified, of whom 18 (38.3%) had Type 1 diabetes. Mean age and disease duration at presentation were 59.2 +/- 13.4 (sd) and 16.2 +/- 11.2 years, compared with 59.7 +/- 12.6 and 16.3 +/- 11.2 years, respectively, in the controls. Twenty-one (44.7%) of those with Charcot had died, after a mean interval of 3.7 +/- 2.8 years. This compared with 16 (34.0%) after a mean 3.1 +/- 2.7 years in the control group. Mean duration of follow-up in the survivors was 4.7 +/- 4.9 years (Charcot) and 5.3 +/- 3.9 years (controls). A total of 11 (23.4%) Charcot patients had had a major amputation on the side of the index lesion, compared with five (10.6%) controls. There was no difference between the two groups (P > 0.05, Chi-square). CONCLUSIONS: The mortality in this group of patients with Charcot foot was higher than expected. Nevertheless, there was no difference between those with Charcot and those with uncomplicated neuropathic ulceration. It is possible that it is neuropathy, rather than Charcot osteoarthropathy, which is independently associated with increased mortality in diabetes. The mechanism underlying any such association is not known. There is a need for a formal, prospective, multicentre study to investigate the life expectancy and cardiovascular risk of those with Charcot osteoarthropathy.  相似文献   
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Gossypol has been shown to inhibit steroidogenesis in leydig cells. This study examined the mechanism of this action by investigating the effect of gossypol on leydig cell hCG receptor binding, adenylate cyclase activity and cyclic AMP production in leydig cells. Gossypol had no effect on hCG binding to cell membranes but inhibited LH-stimulated cyclic AMP production in whole purified leydig cells. It also reduced the stimulation caused by LH, Gpp(NH)p, forskolin and fluoride in membranes from leydig cells and also from liver. It is therefore possible that gossypol affects cyclic AMP production at the level of ATP conversion to cyclic AMP, although effects on the G-protein and catalytic subunit cannot be ruled out.  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   
9.
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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