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Background: Previous studies documented that near-infrared spectroscopy values were affected by factors related to optical path length, such as hemoglobin concentration, the differential path length factor, skull thickness (t-skull), and the area of the cerebrospinal fluid layer (a-CSFL). Lately, the NIRO-100 (Hamamatsu Photonics, Hamamatsu, Japan) has provided a tissue oxygen index (TOI) that theoretically is not supposed to be affected by optical path length. Therefore, the authors hypothesized that TOI is not influenced by the above-described individual factors.

Methods: Cardiac surgical or neurosurgical 103 patients (65 men and 39 women; aged 63 +/- 14 yr) were studied. TOI and regional cerebral oxygen saturation (rSO2) (INVOS 4100; Somanetics, Troy, MI) were measured sequentially on patients in a resting state. The t-skull and a-CSFL were calculated using computed tomographic image slices of the head corresponding with the position of near-infrared spectroscopy sensors. The effects of these two factors, hemoglobin concentration and mean arterial pressure, on TOI and rSO2 values were evaluated by linear regression analysis.

Results: Simple linear regression analysis showed that mean arterial pressure (r = 0.27, P = 0.008), t-skull (r = 0.22, P = 0.034), a-CSFL (0.26, P = 0.012), and hemoglobin concentration (r = 0.42, P < 0.0001) were significant determinants of rSO2. Multiple linear regression analysis showed that hemoglobin concentration (r = 0.34, P < 0.001), a-CSFL (r = -0.252, P = 0.012), and t-skull (r = 0.22, P = 0.037) were significant determinants of rSO2. On the other hand, simple and multiple linear regression analysis showed that there was no significant determinant of TOI.  相似文献   

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A rare case of urinary bladder carcinoma with granulocyte colony stimulating factor (G-CSF) production was reported. In an 83-year-old female, marked neutrophilia in the peripheral blood decreased from 132,500/mm3 to 3,300/mm3 after tumour resection. The tumour was a transitional cell carcinoma. The serum G-CSF level reduced from 238 pg/ml pre-operatively to normal (60 pg/ml) after the operation. Immunohistochemical investigation of the resected tumour with monoclonal antibody specific for G-CSF revealed positive staining in the carcinoma cells, confirming G-CSF secretion.  相似文献   
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J Tamaoki  A Chiyotani  E Tagaya  N Sakai    K Konno 《Thorax》1994,49(6):545-548
BACKGROUND--Anticholinergic bronchodilator drugs improve lung function in chronic bronchitis but less is known of their effects on the volume and physical properties of sputum in conditions associated with excessive airway secretions. This study examines the effects of the regular use of oxitropium bromide in such patients. METHODS--The study was conducted in a parallel, double blind, placebo controlled fashion. Patients were divided into two groups: the first group (n = 17) received oxitropium bromide from a metered dose inhaler (two puffs three times daily; 100 micrograms/puff) for eight weeks, and the second group (n = 16) received placebo. Lung function was measured as forced expiratory volume in one second (FEV1) and vital capacity. In evaluating airway secretion, daily amount of expectorated sputum, percentage solid composition, viscoelastic properties including elastic modulus and dynamic viscosity, and sputum microbiology were determined. RESULTS--Oxitropium bromide increased FEV1 and decreased the mean (SE) sputum production from 61(4) to 42(3) g/day after treatment, whereas placebo had no effect. Bacterial density and sputum flora were unchanged, but solid composition and elastic modulus increased from 2.52(0.43)% to 3.12(0.34)%, and 68(12) dyne/cm2, respectively, in the group taking oxitropium bromide. CONCLUSIONS--Regular treatment with oxitropium bromide not only improves airflow limitation but also reduces sputum production, probably through the inhibition of both mucus secretion and water transport, the latter component being predominant.  相似文献   
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Notch receptors and their ligands contribute to many developmental systems, but it is not apparent how they function after birth, as their null mutants develop severe defects during embryogenesis. Here we used the Cre-loxP system to delete the Delta-like 1 gene (Dll1) after birth and demonstrated the complete disappearance of splenic marginal zone B cells in Dll1-null mice. In contrast, T cell development was unaffected. These results demonstrated that Dll1 was dispensable as a ligand for Notch1 at the branch point of T cell-B cell development but was essential for the generation of marginal zone B cells. Thus, Notch signaling is essential for lymphocyte development in vivo, but there is a redundancy of Notch-Notch ligand signaling that can drive T cell development within the thymus.  相似文献   
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Summary We have examined the nonparallel changes in tampanic membrane temperatures (T ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation.  相似文献   
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