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991.
L B Beerman W H Neches F J Fricker R A Mathews D R Fischer S C Park C C Lenox J R Zuberbuhler 《The American journal of cardiology》1983,51(9):1530-1534
Disorders of rhythm or conduction in patients with transposition of the great arteries (TGA) after the Mustard operation have been widely reported. This study provides a systematic evaluation of the electrophysiologic function of 87 survivors of the Mustard operation at a single institution. Surface electrocardiograms were reviewed in all 87 patients, Holter monitoring data in 26 patients, exercise electrocardiograms in 21 patients, and invasive electrophysiologic data in 61 patients. Surface electrocardiograms showed normal sinus rhythm in 52%, sinus node dysfunction in 27%, and atrioventricular block in 16%. Holter monitoring was obtained in an unselected subgroup of 26 patients who had a mean age of 12 years and a mean interval from operation of 9 years. Sinus node dysfunction was found in 58%, atrioventricular block in 27% ventricular ectopy in 50%, supraventricular ectopy in 27%, and no abnormalities in only 8%. Intracardiac electrophysiologic evaluation showed a high frequency of abnormal sinus node recovery times and suboptimal response of the atrioventricular-conduction system to rapid atrial pacing. When all modalities used in this study were considered, sinus node dysfunction occurred in 47%, ectopy in 34% and atrioventricular block in 23%. Although only 30% of patients had no evidence of arrhythmia, symptoms of rhythm or conduction disturbances were rare. 相似文献
992.
The rate at which CO displaces oxygen from combination with hemoglobin in intact red cells was measured spectrophotometrically in whole blood thin films that minimize unstirred layer extra-cellular diffusion barriers. A step-change was made in CO tension from zero to one of four values (2, 7, 21 and 70 Torr) during a constant background of one of eight O2 tensions (0, 40, 70, 100, 153, 214, 285 and 428 Torr). For PO2 greater than 100 Torr measured red cell initial CO uptake rates were compared with calculated rates at the same PCO-PO2 based on the Gibson-Roughton rate equation (Gibson and Roughton, Proc. R. Soc. B 143: 310-334, 1955) for a well mixed Hb solution. Measured CO uptake rates expressed as initial rate of saturation change (delta S/delta t) quantitatively followed the theoretical rate equation (time in seconds) [sequence: see text] These measurements provide new values for theta CO, the specific conductance of whole blood (ml.min-1.Torr-1; PCO, PO2 in Torr): [sequence: see text] These results signify that in vivo, in normoxia and hyperoxia, red cell CO uptake rate is wholly reaction rate limited and that pulmonary capillary red cell CO diffusion equilibrium is rapidly achieved. The Bohr-Krogh assumption that red cell PCO = 0 during CO uptake is untrue. 相似文献
993.
Identification and characterization of a reptilian GnRH receptor from the leopard gecko 总被引:5,自引:0,他引:5
Gonadotropin-releasing hormone (GnRH) plays a pivotal role in the regulation of reproductive functions through interactions with its specific receptor. We describe the first molecular cloning and characterization of a full-length GnRH receptor (GnRHR) from the leopard gecko Eublepharis macularius. It has a distinct genomic structure consisting of five exons and four introns, compared with all the other reported GnRHR genes. A native GnRH form, cGnRH-II, stimulated inositol phosphate (IP) production in COS-7 cells transiently transfected with the GnRHR, in a dose dependent manner. The mRNA was expressed in all the tissues and organs examined. Molecular phylogenetic analysis revealed that the cloned GnRHR belongs to the type 2/nonmammalian I GnRHR. Low-expression levels were observed from the pituitary glands of reproductively active leopard geckos, indicating the possibility that there is at least one more type of GnRHR highly expressed in the pituitary gland for the gonadotropin secretion in this reptile. 相似文献
994.
995.
996.
Jonghee Yoon Kyoohyun Kim HyunJoo Park Chulhee Choi Seongsoo Jang YongKeun Park 《Biomedical optics express》2015,6(10):3865-3875
The characterization of white blood cells (WBCs) is crucial for blood analyses and disease diagnoses. However, current standard techniques rely on cell labeling, a process which imposes significant limitations. Here we present three-dimensional (3D) optical measurements and the label-free characterization of mouse WBCs using optical diffraction tomography. 3D refractive index (RI) tomograms of individual WBCs are constructed from multiple two-dimensional quantitative phase images of samples illuminated at various angles of incidence. Measurements of the 3D RI tomogram of WBCs enable the separation of heterogeneous populations of WBCs using quantitative morphological and biochemical information. Time-lapse tomographic measurements also provide the 3D trajectory of micrometer-sized beads ingested by WBCs. These results demonstrate that optical diffraction tomography can be a useful and versatile tool for the study of WBCs.OCIS codes: (170.1530) Cell analysis, (180.3170) Interference microscopy, (180.6900) Three-dimensional microscopy 相似文献
997.
998.
[Purpose] This study aims to investigate the effects of mental practice on unilateral
neglect in patients with chronic stroke. [Subjects] The subjects of this study included 30
patients with chronic unilateral neglect. [Methods] The subjects were randomly divided
into either the experimental group (EG) or control group (CG). All subjects received a
standard rehabilitation program. In addition to the standard rehabilitation, the EG
subjects received mental practice (5 days a week for 4 weeks) for 10 minutes. To compare
two groups, line bisection test (LBT) and star cancellation test (SCT) were conducted.
[Results] Both groups showed significant improvement in the LBT and SCT. There were
statistically significant differences in the changes in LBT, but there were no significant
differences in the changes in the SCT between both groups. [Conclusion] This study
demonstrated that mental practice may be a valuable additional rehabilitation method in
the chronic stage of neglect.Key words: Mental practice, Stroke, Unilateral neglect 相似文献
999.
KyoChul Seo Seung Hwan Park KwangYong Park 《Journal of Physical Therapy Science》2015,27(7):2313-2315
[Purpose] We investigated how diaphragm respiration exercises can affect pulmonary
function in long-term male smokers in their twenties. [Subjects and Methods] Twenty-eight
healthy males between 20 and 29 years of age were randomly divided into an experimental
and a control group (14 members each). The experiment was conducted during 30 min
sessions, 3 times a week for 4 weeks. The experimental group performed diaphragm
respiration exercises and the control group performed exercises using MOTOmed. Pulmonary
function (tidal volume, breathing capacity, inspiratory reserve volume, inspiratory
capacity, and expiratory reserve volume) was evaluated and analyzed before and after the
experiment. [Results] Our results revealed significant increases in tidal volume,
inspiratory reserve volume, inspiratory capacity, and breathing capacity in the
experimental group. These increases were greater in the experimental group than in the
control group. [Conclusion] In our study, the experimental group which performed diaphragm
respiration exercises showed a greater improvement in pulmonary function compared with the
control group. It is hypothesized that greater improvement in pulmonary function is
expected if diaphragm respiration exercises are implemented taking into account the age of
the smokers.Key words: Pulmonary function, Diaphragm respiration exercise, Smoking 相似文献
1000.