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11.
Chest radiographs and chest computed tomography (CT) scans were compared in 203 patients with newly diagnosed Hodgkin disease. The incidence of positive findings was tabulated from six intrathoracic lymph node groups, lung parenchyma, pericardium, pleura, and chest wall. The discordant cases were assessed to determine impact on clinical management. The CT scans provided additional evidence of disease involvement, ranging from 0% to 15% at each of the designated anatomic sites. Treatment was altered in 9.4% of all patients (19 of 203), including 13.8% (nine of 65) of those undergoing radiation therapy alone and 8.2% (ten of 122) of those undergoing combined-modality treatment. We conclude that routine chest CT examinations are valuable in the clinical management of those patients for whom radiation therapy is planned. 相似文献
12.
The use of deep inspiration preceding the valsalva maneuver and rapid expiration in color doppler imaging of the lower extremity veins 总被引:1,自引:0,他引:1
Jing Gao MD Elias Kazam MD William Rubenstein MD Joseph P. Whalen MD Tom Hom RDMS RT 《Clinical imaging》1993,17(4):266-268
Deep inspiration preceding Valsalva maneuver and rapid expiration immediately following it (DIVE) enhance venous blood flow on color Doppler flow imaging (CDI). The effect of DIVE was assessed in 115 consecutive lower extremity examinations. Of these, 95 or 115 (83%) had negative CDI sonograms, and 20 of 115 (17%) had partially (six of 115) or completely (14 of 115) occluding deep vein thrombosis. DIVE enhanced venous blood flow in 68% of the negative cases, resulting in transient venous distention, and/or more complete color filling, and/or greater spectral flow velocities. The 14 cases with completely occluding thrombi showed no response to DIVE. Six cases with partially occluding thrombi showed moderate to mild response to DIVE, with improved color delineation of the residual patent lumen around the thrombus. The authors conclude that DIVE facilitates deep venous CDI, especially when compression cannot be used to augment venous flow. 相似文献
13.
Kenjiro Shirasawa Keiichiro Akai Yukihiro Kawaguchi Shotaro Maeda Sadao Nagahara Hiroshi Toyoda Takeshi Kurata 《Pathology international》1979,29(3):435-455
A4-moth-old male infant predisposed to allergic dermatitis acquired widespread eczema vaccinatum by contacts with a recently vaccinated sibling. He died of acute purulent peritonitis following a perforation of multiple duodenal ulcers. Fluorescence immunocytochemical and electron microscopic studies on the skin lesions revealed the presence of viral antigens and numerous virus particles compatible morphologically with those of the mature form from the same batch of smallpox vaccine given to the sibling. A large number of virus particles in the developmental form were also predominantly scattered in the cytoplasm of cells at the stratum malpighii of the epidermis as well as in neutrophils and macrophages in the skin lesions. The virus isolation from the skin lesions was done by using the HeLa cells and the human embryonic lung fibroblasts. No abnormal laboratory data were noted in immunoglobulins. On the basis of atrophy of the thymus and other lymphatic tissues and an appearance of large pyroninophilic cells in association with blastoid transformation, the authors discussed a possible participation of the disturbance of cellular immunity secondary to the virus infection in the development of the disease. ACTA PATH. JAP. 29 : 435–455, 1979. 相似文献
14.
Neuromuscular changes after long-lasting mechanically and electrically elicited fatigue 总被引:1,自引:0,他引:1
Central fatigue was investigated under an isolated active condition whereby the possible effects of supraspinal fatigue were
minimized. Therefore, ten subjects were fatigued by simultaneously and repeatedly mechanically stretching and electrically
stimulating their calf muscles for 1 h. This was performed using an ankle ergometer. The active fatigue task included a total
of 2400 muscle stretches with an intensity of 10% of the maximal voluntary contraction (MVC). This protocol clearly impaired
neuromuscular function, as revealed by a significant reduction in MVC (P<0.01) and the neural input to the muscle (average EMG) (P<0.01–0.001). The interpolated nerve stimulation compensated for this force loss by 4.28% (P<0.05). Stretch-reflex recordings revealed a notable post-fatigue reduction in the peak-to-peak amplitude (59.1%, P<0.01) and stretch-resisting force of the muscle (14.1%, P<0.01). The maximal H-reflex declined by 50.5% (P<0.001) and did not recover while the leg was kept ischemic. It is suggested that the existing protocol with minor metabolic
loading can induce central fatigue, which seems to be of reflex origin from the fatigued muscle. Although the role of presynaptic
inhibition of Ia terminals is possibly reinforced, disfacilitation via reduced spindle sensitivity cannot be excluded.
Electronic Publication 相似文献
15.
A. N. Chalazonitis MD Ph.D D. Koumarianos RT J. Tzovara MD P. Chronopoulos MD 《Journal of digital imaging》2003,16(2):216-229
Over the past decade, the technology that permits images to be digitized and the reduction in the cost of digital equipment allows quick digital transfer of any conventional radiological film. Images then can be transferred to a personal computer, and several software programs are available that can manipulate their digital appearance. In this article, the fundamentals of digital imaging are discussed, as well as the wide variety of optional adjustments that the Adobe Photoshop 6.0 (Adobe Systems, San Jose, CA) program can offer to present radiological images with satisfactory digital imaging quality. 相似文献
16.
Kyröläinen H Pullinen T Candau R Avela J Huttunen P Komi PV 《European journal of applied physiology》2000,82(4):297-304
The present study was designed to investigate interactions between running economy and mechanics before, during, and after
an individually run marathon. Seven experienced triathletes performed a 5-min submaximal running test on a treadmill at an
individual constant marathon speed. Heart rate was monitored and the expired respiratory gas was analyzed. Blood samples were
drawn to analyze serum creatine kinase activity (S-CK), skeletal troponin I (sTnI), and blood lactate (B-La). A video analysis
was performed (200 frames · s−1) to investigate running mechanics. A kinematic arm was used to determine the external work of each subject. The results of
the present study demonstrate that after the marathon, a standardized 5-min submaximal running test resulted in an increase
in oxygen consumption, ventilation, and heart rate (P < 0.05), with a simultaneous decrease in the oxygen difference (%) between inspired and expired air, and respiratory exchange
ratio (P < 0.05). B-La did not change during the marathon, while sTnI and S-CK values increased (P < 0.05), peaking 2 h and 2 days after the marathon, respectively. With regard to the running kinematics, a minor increase in
stride frequency and a similar decrease in stride length were observed (P < 0.01). These results demonstrate clearly that weakened running economy cannot be explained by changes in running mechanics.
Therefore, it is suggested that the increased physiological loading is due to several mechanisms: increased utilization of
fat as an energy substrate, increased demands of body temperature regulation, and possible muscle damage.
Accepted: 20 March 2000 相似文献
17.
Koga H Sakisaka S Yoshitake M Harada M Kumemura H Hanada S Taniguchi E Kawaguchi T Kumashiro R Sata M 《International journal of molecular medicine》2002,9(6):621-626
Primary sclerosing cholangitis (PSC) is known to be frequently associated with inflammatory bowel diseases. In a rat with self-filling blind loop (SFBL), a proposed animal model for PSC, hepatobiliary inflammation has previously been demonstrated. In this study, we assessed the involvement of lipopolysaccharide (LPS), a bacterial endotoxin, in the pathogenesis of hepatobiliary inflammation of the SFBL model. The hepatic localization of LPS was examined by immunohistochemistry using an anti-lipid A antibody. The portal blood concentration of LPS was measured by an endotoxin-specific chromogenic Limulus test (Endospecy test). LPS was localized in the biliary epithelial cells (BECs) of rats with SFBL, and the portal blood concentration of LPS was significantly higher than that of sham-operated rats. Development of hepatobiliary inflammation, peribiliary fibrosis, and injury to the intestinal mucosa were histologically confirmed. Constriction in the biliary trees was radiologically demonstrated. These findings suggested that abnormal accumulation of LPS, which may be derived from portal blood, in BECs was involved in the pathogenesis of hepatobiliary inflammation with intestinal injury. 相似文献
18.
Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献
19.
20.
Summary The relationships between ground reaction forces, electromyographic activity (EMG), elasticity and running velocity were investigated
at five speeds from submaximal to supramaximal levels in 11 male and 8 female sprinters. Supramaximal running was performed
by a towing system. Reaction forces were measured on a force platform. EMGs were recorded telemetrically with surface electrodes
from the vastus lateralis and gastrocnemius muscles, and elasticity of the contact leg was evaluated with spring constant
values measured by film analysis. Data showed increases in most of the parameters studied with increasing running speed. At
supramaximal velocity (10.36±0.31 m×s−1; 108.4±3.8%) the relative increase in running velocity correlated significantly (P<0.01) with the relative increase in stride rate of all subjects. In male subjects the relative change in stride rate correlated
with the relative change of IEMG in the eccentric phase (P<0.05) between maximal and supramaximal runs. Running with the towing system caused a decrease in elasticity during the impact
phase but this was significant (P<0.05) only in the female sprinters. The average net resultant force in the eccentric and concentric phases correlated significantly
(P<0.05−0.001) with running velocity and stride length in the maximal run. It is concluded that (1) increased neural activation
in supramaximal effort positively affects stride rate and that (2) average net resultant force as a specific force indicator
is primarily related to stride length and that (3) the values in this indicator may explain the difference in running velocity
between men and women. 相似文献