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1.
Discrimination of well-differentiated pulmonary adenocarcinoma from reactive bronchioloalveolar epithelium can be difficult on routine histology, especially with small biopsies. Ancillary studies to help in this distinction are desirable. p63, a p53-homologous nuclear protein, is a marker of reserve cells of the bronchus and terminal lobular unit. In this study, 33 cases of adenocarcinoma (20 open lung and 13 transbronchial/percutaneous biopsies) and 43 cases of benign lungs with fibrosis and metaplasia (22 open lung and 21 transbronchial/percutaneous biopsies) were studied for nuclear p63 expression by immunohistochemistry (Dako, Carpinteria, CA, USA). Five additional cases each of atypical adenomatous hyperplasia and adenosquamous carcinoma and three cases of squamous carcinoma (all open lung biopsies) were also stained. The diagnostic categories of benign lung conditions were usual interstitial pneumonia, parenchymal scar, cryptogenic organizing pneumonia and diffuse alveolar damage. In neoplastic cases, p63 positivity was calculated as percentage of all tumor cells examined. In areas of normal lung, p63 decorated the reserve cells of large and small airways and occasional cells of the distal lobular unit. In fibrotic reactive processes, an interrupted but distinct pattern of nuclear staining was present in all cases, with staining of basal cells of the airways as well as bronchiolar- and squamous-metaplastic epithelium (43/43, 100%). p63 immunoreactivity was less uniform in areas of acute lung injury within these cases. One adenocarcinoma and two cases of atypical adenomatous hyperplasia showed strong immunoreactivity (>80%), while three adenocarcinomas highlighted only rare tumor nuclei (<5% of tumor cells). Morphologic areas where p63 immunostaining was not helpful included the junction of normal lung and lepidic growth of adenocarcinoma, and retrograde spread of adenocarcinoma into small airways. Our results highlight the differential expression of p63 across various bronchioloalveolar lesions. Moreover, p63 may be helpful in distinguishing reactive from neoplastic glandular proliferations in the lung.  相似文献   
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Abstract: In order to determine the pulmonary toxicity of kerosene and its ignition product (soot) in asbestos exposed subjects, the activities of phase I and phase II drug metabolizing enzymes in rat lungs after single intratracheal coexposure to Indian chrysotile asbestos and kerosene or its soot and Indian chrysotile were assayed. Exposure to kerosene or its soot resulted in a significant increase in the level of microsomal cytochrome P-450 and the activity of P-450 dependent monooxygenase, benzo(a)pyrene hydroxylase, as well as in the activities of microsomal epoxide hydrase and cytosolic glutathione-S-transferase (GST). However, in chrysotile exposed animals a reverse pattern in these parameters was recorded. The co-exposure to chrysotile and kerosene or chrysotile and soot led to a significant depletion in cytochrome P-450 level and a decrease in the activities of benzo(a)pyrene hydroxylase, epoxide hydrase and GST when compared to kerosene and soot controls, respectively. These results suggest that asbestos by altering the pulmonary drug metabolizing enzyme system may increase the toxic potential of kerosene and its ignition product in the respiratory system.  相似文献   
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The effect of aqueous and alcohol extracts of the fruits and leaves of Pongamia pinnata (Linn.) Merr. (Syn. Pongamia glabra Vent, leguminosae) on the spontaneous movements of both the whole worm and the nerve-muscle preparation of Setaria cervi and on the survival of micro fi lariae in vitro was studied. The aqueous and alcohol extracts of fruits and the alcohol extract of leaves caused an inhibition of spontaneous movements of the whole worm and the nerve-muscle preparation of S. cervi. The initial stimulatory effect was not observed with the aqueous extract of fruits on the nerve-muscle preparation. The concentration required to inhibit the movements of the whole worm preparation was 250 micro g/mL for aqueous, 120 micro g/mL for alcohol extract of fruits and 270 microgram/mL for alcohol extracts of the leaves. The concentrations of P. pinnata extracts required to produce an equivalent effect on the nerve-muscle preparation were 25 micro g/mL, 5 micro g/mL and 20 micro g/mL, respectively, suggesting a cuticular permeability barrier.  相似文献   
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Antibody to cardiolipin, lupus anticoagulant, and fetal death   总被引:9,自引:0,他引:9  
We compared the concordance and predictive powers of activated partial thromboplastin time (APTT) and of IgG and IgM antibody to cardiolipin (aCL), for predicting fetal death in 50 pregnant women with systemic lupus erythematosus (SLE) and/or lupus anticoagulant. Overall concordance of any abnormal determination of aCL during pregnancy with any abnormal determination of APTT was 76% (0.05 less than p less than 0.10). Fetal death occurred in 6/12 (50%) of patients with high APTT compared to 5/20 (16%) of patients with low APTT; fetal death occurred in 10/13 (77%) of patients with abnormal aCL and in 2/37 (5%) of patients with normal aCL. Sensitivity for predicting fetal death was .55 for APTT and .85 for aCL; specificity was .81 for APTT and .92 for aCL. Abnormalities of APTT and aCL are sufficiently frequently discordant to prevent equation of the 2 assays. ACL is the better assay for predicting fetal death.  相似文献   
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Purpose: To determine if older adult, novice wheelchair users who drive a power wheelchair with a JoyBar control complete maneuverability tasks in less time and with less error than those who drive a power wheelchair with a standard joystick control.

Materials and methods: A parallel randomized controlled trial design conducted at a medical rehabilitation and research centre with ambulatory older adults aged 60 and above (n?=?27). The intervention was the JoyBar alternative wheelchair control. The primary outcome measure was total time to complete each of the two maneuverability tasks. The secondary outcome measure was total number of errors during each of the maneuverability tasks.

Results: An independent, two sampled t-test was conducted and revealed that the JoyBar group took a greater amount of time to complete both maneuverability tasks than the control group (p?p?Conclusions: Maneuverability of a powered wheelchair by novice wheelchair users was not improved through the use of the JoyBar when compared to a standard wheelchair joystick, as measured by rates of error and time to complete maneuverability tasks.
  • Implications for rehabilitation
  • Clients who are new to powered wheelchair use may perform maneuverability tasks faster, with equivalent accuracy, using a standard joystick versus the JoyBar.

  • Clients who use a JoyBar may require adjustments to the programming of their wheelchair to ensure optimal performance.

  • Additional training may be required to achieve proficiency in maneuverability tasks with a JoyBar versus a standard joystick.

  相似文献   
8.
Forskolin, a diterpene, directly stimulates adenylate cyclase and also potentiates receptor mediated stimulation of this enzyme by many stimulatory agonists. We exploited the potentiating effect of forskolin to test the hypothesis that activation of adenylate cyclase contributes to myocardial reactive hyperaemia, especially by release of adenosine at the time of brief coronary occlusions. In 10 open chest dogs, intracoronary forskolin infusions which produced plasma concentrations between 0.22 and 0.34 mumol.litre-1 slightly increased coronary blood flow and had no effect on haemodynamics or myocardial metabolism. Under these conditions, though peak reactive hyperaemic flow rates were not affected, forskolin infusions reversibly potentiated repayments of flow debt by 28, 25 and 27% following coronary occlusions of 15 s, 20 s and 30 s, respectively (p less than 0.05). In another seven dogs, after observations of the effects of forskolin (0.16-0.26 mumol), 10 mumol of 8-phenyltheophylline, a potent adenosine antagonist, was infused simultaneously with forskolin into the coronary arteries. Forskolin increased debt repayments by about 23-27% following 15 s, 20 s and 30 s occlusions, but with simultaneous 8-phenyltheophylline, forskolin induced increments in the debt repayments were reduced significantly (p less than 0.05). These results indicate that adenylate cyclase contributes to myocardial reactive hyperaemia, and adenosine has a significant role as metabolic regulator of reactive hyperaemia through activation of adenylate cyclase.  相似文献   
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