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71.
从绵毛马兜铃(Aristolocha mannisima Hance)中分得一个马兜铃酸倍半萜的酯类化合物,经红外、紫外、高分辩质谱和多种一维和二维核磁共振谱鉴定,确定了其骨架结构及顺反构型,命名为马兜铃酸萜酯I。  相似文献   
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Thoracic computed tomographic (CT) scans of 250 patients with newly diagnosed or recurrent lymphoma revealed thoracic wall involvement in 24 patients (11 with Hodgkin disease, 13 with non-Hodgkin lymphoma). Thoracic wall involvement occurred without contiguous mediastinal or parenchymal involvement in 17 patients. Of these, 13 patients had masses beneath the pectoralis muscles or within the breast, and four had masses arising from the ribs. Five additional patients had mediastinal masses with thymic involvement and parasternal extension through the thoracic wall. Pulmonary parenchymal lymphoma with thoracic wall invasion was noted in the remaining two patients. In five of nine patients receiving radiation therapy, treatment plans were modified by CT demonstration of thoracic wall lymphoma.  相似文献   
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Context  Premutation expansions (55-200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene are frequent in the general population, with estimated prevalences of 1 per 259 females and 1 per 813 males. Several articles have recently described the presence of late-onset neurological symptoms in male carriers of premutation (FMR1) alleles. The main clinical features described in this newly identified syndrome are cerebellar ataxia and intention tremor. Additional documented symptoms include short-term memory loss, executive functional deficits, cognitive decline, parkinsonism, peripheral neuropathy, lower-limb proximal muscle weakness, and autonomic dysfunction. Objective  To study the penetrance of the fragile X–associated tremor/ataxia syndrome (FXTAS) among premutation carriers. Design, Setting, and Participants  Family-based study of 192 individuals (premutation carriers and controls) whose families belong to the Northern or Southern California Fragile X Associations. Data were collected (March 2002-April 2003) through a survey and a standardized neurological examination, which was videotaped and subsequently scored in a blinded fashion. Main Outcome Measures  Penetrance of intention tremor and ataxia among adult carriers (aged =" BORDER="0">50 years) of premutation expansions of the FMR1 gene. Results  Data from the survey of 192 individuals demonstrated an age-related penetrance of the combination of reported intention tremor and gait ataxia in male carriers (17%, 38%, 47%, and 75% [lower-bound estimates] for participants aged 50-59, 60-69, 70-79, and =" BORDER="0">80 years, respectively). The male carrier group had an age-adjusted 13-fold increased risk (95% confidence interval, 3.9-25.4; P = .003) of combined intention tremor and gait ataxia when compared with male controls. The clinical examination data from 93 individuals demonstrated that male carriers experienced more difficulties on each of 3 standardized neurological rating scales compared with controls (P<.05). Female carrier scores were also higher than those of female controls (P<.05) on 2 of the 3 neurological rating scales, but no participant was identified with probable or definite FXTAS. Conclusions  The study demonstrates that older male carriers of premutation alleles of the FMR1 gene are at high risk of developing FXTAS. Since male premutation carriers are relatively common in the general population, older men with ataxia and intention tremor should be screened for the FMR1 mutation, especially if these signs are accompanied by parkinsonism, autonomic dysfunction, or cognitive decline, regardless of family history.   相似文献   
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Background Streptokinase resistance may cause suboptimal thrombolytic therapy. Aim To develop a rapid latex-bead assay to detect streptokinase antibodies. Methods Sera were obtained from 16 patients presenting with acute myocardial infarction (MI) before treatment with streptokinase and 1 and 6 months post treatment, and from 100 controls. Sera were assayed for anti-streptokinase antibodies using a functional streptokinase-neutralising assay. Results Streptokinase-neutralising activity was low in controls (54±5U/ml) and patients prior to treatment (101±18), increasing to 2,110±823 and 1,017±169 at 1 and 6 months (mean±SEM). The latex assay had a sensitivity of 94% and a specificity of 93% for detecting individuals with >350U/ml of streptokinase resistance, which is sufficient to neutralise the drug clinically. Conclusions Estimation of streptokinase resistance using an enzyme immunoassay and a latex bead assay correlated well with serum neutralising activity. This assay can rapidly identify patients who have a high level of streptokinase-neutralising activity.  相似文献   
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Sartoris  DJ; Clopton  P; Nemcek  A; Dowd  C; Resnick  D 《Radiology》1986,160(2):479-483
The radiographic patterns of vertebral-body collapse and/or endplate deformity were examined in 99 autopsy specimens of the thoracolumbar spine with benign and malignant disease. Angling of endplates was found to be highly predictive of underlying malignancy, whereas concavity was more suggestive of benign disease, for both individual vertebral bodies and intact spines (P less than .001). Diffuse-concave, diffuse-angled, and focal-angled patterns were more useful (P less than .001) than the focal-concave pattern (P = .07) in distinguishing between benign and malignant disease for superior endplates, whereas all were equally useful (P less than .025) in inferior endplates. Condition of the adjacent disks, location within the spine, and position of the apex of collapse were not predictive. Although these results and subsequent blinded testing suggest that reliable distinction between benign and malignant vertebral collapse is possible, extrapolation to clinical practice may be inappropriate because of population bias in the study and differences in radiographic quality between autopsy specimens and live subjects.  相似文献   
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