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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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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   
4.
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   
5.
The chive maggot, Bradysia odoriphaga (Yang and Zhang) is an economically important insect pest, affecting many key vegetables, including Chinese chive, especially in northern China. Chlorfenapyr, a halogenated pyrrole insecticide that interferes with mitochondrial oxidative phosphorylation is widely used against B. odoriphaga. In this study, we evaluated selection-induced resistance to chlorfenapyr and fitness costs in B. odoriphaga. The results showed that B. odoriphaga developed 43.32-fold resistance after continuous exposure to chlorfenapyr for over 10 consecutive generations. The life-history traits of chlorfenapyr-resistant and susceptible strains were compared using age-stage, two-sex life table approach. No significant effects were observed on the longevity and pre-adult period. However, reduction in the total pre-oviposition period (TPOP) and fecundity (eggs/female) were observed in the resistant strain. Moreover, the demographic parameters such as intrinsic rate of increase (r), net reproductive rate (R0) and finite rate of increase (λ) were also decreased significantly in the resistant strain compared to the susceptible strain. These results showed the potential of B. odoriphaga to develop resistance against chlorfenapyr under continuous selection pressure. Furthermore, there was a fitness cost linked with chlorfenapyr resistance in B. odoriphaga. We conclude that a better knowlegde on the trade-off at play between resistance degree and fitness cost could be crucial for developing further management of B. odoriphaga in China.  相似文献   
6.
Monosodium glutamate (MSG) is a food additive with a wide range of biological effects but its high dose and prolonged use can cause a toxic effect on the liver. Therefore, the present study was aimed at investigating the role of vitamin C in MSG-induced hepatotoxicity in rats. MSG was administered to rats (by gavage) at a dose of 6 mg/g body weight for 10 days to induce hepatotoxicity, and vitamin C at a dose of 500 mg/kg body weight was coadministered to evaluate its ameliorating effect by measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in serum; superoxide dismutase (SOD) and catalase activities in liver fraction; lipid peroxidation; and liver weight. It was found that MSG significantly (P?<?0.05) induced lipid peroxidation (LPO), increased liver weight, and increased activity of SOD and catalase in the liver of animals. The activity of ALT and AST was also increased in the serum on MSG administration. Vitamin C (500 mg/kg) coadministered with MSG significantly reduced LPO and liver weight and decreased the hepatic activity of catalase, but the activity of SOD was not reduced significantly. Also, a significant reduction in ALT and AST activity was observed. MSG induced oxidative stress and hepatic toxicity in the experimental animals at a dose of 6 mg/g body weight. Vitamin C significantly reduced the oxidative stress and hepatic toxicity induced by MSG, thereby providing a protective effect against the MSG-induced hepatotoxicity. The protective effect is associated with decreased LPO and liver weight and decreased activities of catalase, ALT, and AST.  相似文献   
7.
Epicardial resident stem cells are known to differentiate into cardiomyocytes during cardiac development, amongst other cell types. Whether epicardium-derived progenitor cells (EPDCs) retain this plasticity in the adult heart has been the topic of heated scientific debate. Priming with thymosin beta 4, a peptide which has been suggested to be critical for cardiac development and to have cardio-protective properties, was recently shown to induce differentiation of EPDCs into cardiomyocytes in a small animal model of myocardial infarction. This finding is in stark contrast to another recent study in which thymosin beta 4 treatment following myocardial infarction did not induce cardiomyocyte differentiation of EPDCs. While EPDCs seem to exhibit overall cardio-protective effects on the heart following myocardial infarction, they have not been shown to differentiate into cardiomyocytes in a clinically relevant setting. It will be important to understand why the ability of one therapeutic agent to induce cardiomyocyte differentiation of EPDCs seemingly depends on a single variable, i.e. the time of administration. Furthermore, in light of a recent report, it appears that thymosin beta 4 may be dispensable for cardiac development.  相似文献   
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The presented investigation theoretically studies the physical characteristics of a two-dimensional incompressible hybrid nanofluid in a non-uniform annulus where the boundaries are flexible. A mixed convective peristaltic mechanism is implemented to model blood-based nanofluids using two different nanoparticles (Ag + Al2O3). Convective boundary conditions are employed and different forms of nanoparticles are discussed (bricks, cylinders and platelets). The problem is shortened by engaging a lubrication method. Exact expressions for the temperature of cumulative heat source/sink standards, hemodynamic velocity, pressure gradient and streamlines of different shapes of nanoparticles are obtained. Special cases of pure blood and the Al2O3 nanofluid of our model are derived. A comparison is set between nanofluids and hybrid nanofluids from which we observed variations in heat transfer rate in different regions due to the oscillatory nature of the waves. The current model has the potential to be useful for applications related to the metabolic structures that play a vital role in heat sources inside the human body.

The presented investigation theoretically studies the physical characteristics of a two-dimensional incompressible hybrid nanofluid in a non-uniform annulus where the boundaries are flexible.  相似文献   
10.
Chondrodermatitis nodularis helicis (CNH) is a rare condition of the pinna affecting mainly adults. A pediatric case of this condition is presented in the current report, and the literature of pediatric CNH is reviewed.  相似文献   
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