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41.
The phospholipid-hydrolyzing enzyme phospholipase A2 (PLA2) (EC 3.1.1.4) exists in several forms which can be located in the cytosol or on cellular membranes. We review briefly cellular regulatory mechanisms involving covalent modification by protein kinase C and the action of Ca2+, cytokines, G proteins and other cellular proteins. The major focus is the role of phospholipid structure on PLA2 activity, including (1) the mechanism of PLA2 action on synthetic phospholipid bilayers, (2) perturbation of synthetic and cellular membranes with lipophilic agents and membrane-interactive peptides and (3) the ability of these agents to activate endogenous PLA2 activity, with emphasis on the venom and plant toxins melittin, cardiotoxin and Pyrularia thionein. 相似文献
42.
David S H Bell James H O'Keefe 《Journal of the American College of Cardiology》2007,50(18):1810; author reply 1810-1810; author reply 1811
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Superior vena caval obstruction: a 10-year experience 总被引:3,自引:0,他引:3
One hundred and fifty-nine patients with symptoms of superior vena caval obstruction who presented to two major hospitals over a 10-year period, from 1970 to 1979, were reviewed. Lung cancer was the most common histological diagnosis. The most common symptoms were dyspnoea and a feeling of fullness in the head. The most common physical findings were dilatation of the neck or chest wall veins, or oedema of the face and arms. Superior mediastinal widening was the most common radiological abnormality. No significant morbidity was associated with any diagnostic procedure. Only patients with lymphoma had a significantly longer survival period, both from the diagnosis of the disease, and from the onset of the symptoms of superior vena caval obstruction. There is no evidence that superior vena caval obstruction is an absolute medical emergency. Appropriate diagnostic steps should be undertaken to establish the histological diagnosis. The prognosis for some tumour types may be improved by combined modality therapy (chemotherapy plus radiotherapy). 相似文献
47.
Haemodynamic assessment of the femoropopliteal segment: comparison of pressure and Doppler methods using ROC curve analysis 总被引:1,自引:0,他引:1
Combined aorto-iliac and femoropopliteal vascular disease remains a problem in vascular surgery. Arteriography does not provide information on the relative contributions of the two lesions to the presenting symptoms. Aorto-iliac haemodynamics may reveal occult aorto-iliac disease but does not show whether combined proximal and distal reconstruction will be required to provide symptomatic relief. Haemodynamic assessment of both segments may help in this respect. A haemodynamic assessment of the femoropopliteal segment of 72 limbs in 38 patients is reported. The segmental pressure drop between a common femoral arterial cannula and a below-knee occlusion cuff is compared with a non-invasive Doppler method combining both transit time and damping factor. Comparison is made using receiver operating characteristic (ROC) curve analysis. The measurement of segmental pressure drop is more accurate than the Doppler method in detection of femoropopliteal stenoses of greater than 50 per cent of the luminal diameter (P less than 0.05). 相似文献
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A Chalvardjian W G De Marchi V Bell R Nishikawa 《Canadian Medical Association journal》1991,144(3):313-317
OBJECTIVE: To evaluate the effectiveness of the Ayre wooden spatula, the cotton-tipped swab and the Zelsmyr Cytobrush in obtaining endocervical cells. DESIGN: Cross-sectional comparison study. SETTING: Family practice unit. PATIENTS: All postpubertal, nonpregnant women who underwent a routine Papanicolaou smear during a 7-month period. INTERVENTIONS: The three devices were used in each patient in a randomized sequence. An experienced cytotechnologist blinded to the device used evaluated the slides for overall epithelial cellularity (graded from 0 [acellular specimen] to 12 [overloaded sample]), density (the number of groups of five or more endocervical cells) and size of cell clusters (5 to 10 cells per cluster [score of 1], 11 to 100 [2] or more than 100 [3]). MAIN RESULTS: Samples from 2 of the 136 women were rejected because of improper labelling of the slides or failure to use all three devices. Seventy-six (57%) of the smears obtained with the spatula and 71 (53%) with the swab had no endocervical cells, as compared with only 14 (10%) obtained with the Cytobrush (p = 0.001). The overall cellularity (and standard deviation [SD]) of the smears obtained with the Cytobrush (5.69 [SD 1.17], p = 0.001) and the spatula (5.70 [SD 1.46], p = 0.001) was significantly greater than the cellularity of those obtained with the swab (4.31 [SD 1.17]). The Cytobrush yielded significantly more groups of endocervical cells (109.84 per slide) than either the spatula (4.17) or the swab (6.25) (p = 0.001). The Cytobrush also produced larger cell clusters (1.56 [SD 0.67], p = 0.001) than either the swab (0.83 [SD 1.70]) or the spatula (0.64 [SD 0.67]). CONCLUSIONS: The Cytobrush and the spatula should be used instead of the spatula alone or the spatula and the swab for collecting endocervical cells. 相似文献
50.
Michelle M. Macias Conway F. Saylor Kathie B. Haire Nancy L. Bell 《Children's Health Care》2007,36(2):99-115
This study examined the types of stress experienced by maternal and paternal caretakers of children with Neural Tube Defects (NTD) and examined child and family characteristics that correlated with stress. Participants were 71 two-parent families of a child with spina bifida. Parents completed the Parenting Stress Index-Short Form to measure types of stress. Additional measures were completed to investigate variables potentially related to reported stress. Fathers reported significantly higher levels of stress from “dysfunctional parent-child interaction.” Mothers' personal stress correlated with disability and medical characteristics of the child. Fathers reported more stress when the child had maladaptive behaviors and when experiencing fewer social supports and resources. Mothers and fathers coparenting a child with NTD have both common and unique stresses. It is important that both be included in parent support and education initiatives. 相似文献