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121.
(Received for publication on Oct. 24, 1996; accepted on May 12, 1997)  相似文献   
122.
The effects of horizontal cell polarization on spike discharges were explored in superfused preparations of the carp retina. Light-induced discharge patterns of individual units were determined with spot and annulus stimuli of white light. The effects observed were classified in three response modes (common, reversed and transient). They were consistently observed as the tangential distance between the recording and current-injection electrodes was increased up to 400 μm. The common mode of response consisted of off-discharges upon depolarization and on-discharges upon hyperpolarization of horizontal cells. The reversed mode was opposite to the common. The transient mode consisted in transient spike discharges at the on- and off-sets of extrinsic currents injected into horizontal cells. The common mode of response was observed in 3 of 9 ON-center units, all of 20 OFF-center units and in 3 of 21 ON-OFF units. The reversed mode was seen in 6 of 9 ON-center units and in 4 of 21 ON-OFF units. The transient mode was only found in ON-OFF units. ON-center units can be divided into two subgroups: some responded with the common and others with the reversed mode. All OFF-center units showed exclusively the common mode. On the other hand, all 21 ON-OFF units showed the transient mode, but 9 exhibited one or two additional modes of response; 5 of them showed two (common and transient) modes and 4 showed all three modes, depending upon horizontal cells into which polarizing currents were injected.  相似文献   
123.
124.
We analyzed the relation between meningioma and the brain in 50 surgical cases. So-called capsule formation was seen in 20 meningiomas, of which 13 were categorized as thin and 7 as thick. In 21 meningiomas the arachnoid membrane was intact, and 10 meningiomas had no underlying arachnoid membrane. The other 19 tumors showed partial disruption of the arachnoid membrane. The degree of arachnoid disruption correlated with the tumor grade, perifocal edema, pial blood supply on angiography, and tumor size. The existence of brain invasion correlated with the tumor grade and partially with tumor size. In case of invasive tumor, GFAP-positive cells were found deep in the tumor, usually in contact with blood vessels. The axons in gliotic brain often showed degenerative changes such as ballooning or varicose swelling. Meningiomas were usually demarcated by a basement membrane that was collagen type 4 (Col4)-positive. However, atypical and anaplastic meningiomas usually lacked Col4 staining at the interface. In two benign meningiomas that looked like an invasive growth, Col4 staining was seen above the brain. A pia mater-like structure covered the tumor surface in both cases. We could not demonstrate a relation between the expression of matrix metalloproteinase (MMP)-2 or MMP-9 and arachnoid disruption or brain invasion.  相似文献   
125.
The effect of bilirubin treatment on intestinal transport of 2,4-dinitrophenyl-S-glutathione (DNP-SG), a substrate of multidrug resistance-associated protein 2 (MRP2), after application of 1-chloro-2, 4-dinitrobenzene (CDNB), a precursor of DNP-SG, was examined in rat intestine by the in-vitro everted sac, in-situ re-circulating perfusion, and in-situ loop methods. CDNB was taken up rapidly by jejunum and ileum, and the consequent intestinal efflux of DNP-SG, a glutathione conjugated metabolite of CDNB, was significantly higher in jejunum than in ileum in the in-situ and in-vitro studies. Co-administration of bilirubin (100 microM), as well as probenecid (1 mM) or ciclosporin (100 microM), with CDNB decreased the DNP-SG efflux in jejunum significantly, but not in ileum. The suppression of DNP-SG efflux in jejunum was also observed after intravenous administration of bilirubin (85.5 micromol kg-1), in which plasma bilirubin glucuronide levels were approximately 100 microM. In the in-vitro metabolism study, bilirubin exerted no significant effect on CDNB metabolism in the intestinal S9 fraction (supernatant of 9000 g). These results suggested that the diseased states accompanied with hyperbilirubinaemia might have increased the intestinal absorption, or oral bioavailability, of MRP2 substrates by suppressing MRP2 function at the proximal intestinal region.  相似文献   
126.
BACKGROUND: We evaluated the effect of landiolol, a novel ultra-short-acting receptor-selective blocker, on bispectral index scale (BIS). METHODS: Ten patients scheduled for off-pump coronary artery bypass (OPCAB) surgery under fast-track cardiac anesthesia were analyzed. Anesthesia was maintained with appropriate additional administration of fentanyl (total dose: 10-15 microg x kg(-1)) and vecuronium under inhalation of a mixture of oxygen, air and sevoflurane (less than 2%). Landiolol was administered continuously for 5 min, when the heart rate (HR) was 80 or more per minute and the BIS values were kept between 40-60. HR, mean arterial pressure (MAP), cardiac index (CI) and BIS values were recorded at 4 time points (after induction of anesthesia, before administration of landiolol, immediately before comple- tion of administration, and 15 minutes after completion of administration). RESULTS: HR decreased significantly by landiolol administration, but there were no significant changes in MAP, CI and BIS. CONCLUSIONS: This study suggests that landiolol does not affect BIS in OPCAB surgery patients under fast-track cardiac anesthesia.  相似文献   
127.
128.
Background Messenger RNA of liver fatty acid-binding protein (L-FABP) is expressed in proximal tubules of the kidney, and a certain amount is excreted into urine. We analyzed factors relating to the urinary L-FABP excretion in health-check participants.Methods We measured L-FABP in the first morning urine by ELISA in 715 men and 193 women 30–79 years of age who entered a 2-day hospitalized health checkup program. In addition to the routine physical examination and laboratory tests, plasma high-sensitivity C-reactive protein (HSCRP) was assayed.Results In 150 healthy subjects, urinary L-FABP averaged 3.6 ± 0.2µg/g creatinine, whereas the values were significantly increased in patients with hypertension (5.2 ± 0.4, P = 0.010), diabetes mellitus (5.5 ± 0.5, P < 0.001), and chronic hepatitis (5.8 ± 1.0, P = 0.022). Urinary L-FABP excretion was significantly greater in women than in men when the value was related to creatinine. In regression analysis in men, urinary L-FABP was positively correlated with fasting plasma glucose (r = 0.103, P = 0.033) and plasma HSCRP (r = 0.135, P = 0.006).Conclusions It is suggested that renal production and urinary excretion of L-FABP are increased in situations in which arteriosclerosis is promoted, such as hypertension, diabetes mellitus, and cardiovascular inflammation.  相似文献   
129.
The aim of this study was to determine the effects of vasopressin V1 receptor antagonism on regional hemodynamics in spontaneously hypertensive rats (SHR/Izm). Changes in blood flow in the superior mesenteric artery or terminal aorta were measured in rats with a chronically implanted electromagnetic flowmeter. The combination of a non-hypotensive hemorrhage (0.3 ml/100 g weight) and ganglionic blockade with hexamethonium bromide (C6; 25 mg/kg weight) had no effect on mesenteric resistance. On the other hand, subsequent intravenous administration of a peptide vasopressin V1 receptor antagonist (V1A; 10 microg/kg:[d(CH2)5(1)-O Methyl-Tyr(2)-Arg8]-vasopressin) significantly reduced mesenteric resistance in SHR/Izm but had no effect on hindquarter resistance. Furthermore, the infusion of C6 (after pretreatment with hemorrhage plus V1A) induced a marked reduction of blood pressure and a significant decrease in superior mesenteric resistance only in SHR/Izm. Thus, we showed an altered reactivity to V1A in the superior mesenteric and/or hindquarter vascular regions of SHR/Izm, suggesting that maintenance of elevated resistance in the mesenteric vascular bed mainly relates to a potential vasopressin-mediated vasoconstriction and that a new sympathetic vasoconstrictor tone is generated within the superior mesenteric vascular bed to compensate for hypotensive intervention (minor hemorrhage plus V1A) in conscious SHR/Izm.  相似文献   
130.
Peribronchiolar metaplasia (PBM) is a histologic lesion consisting of peribronchiolar metaplasia (PBM) of bronchiolar-type epithelium. Although widely recognized, PBM has received little attention in the pathologic literature and is not known to have clinical significance. We identified 15 cases in which PBM was the only major histologic finding in surgical lung biopsies from patients with interstitial lung disease (PBM-ILD), and we reviewed the clinical, imaging, and pathologic findings. The mean age was 57 years (range, 44-74 years) with 13 females and 2 males. One patient had been a welder with fume and asbestos exposure; another had pigeon exposure. Smoking history was available for 13 patients: three current smokers, one cocaine user, two former smokers, and seven never smokers. Three patients had collagen vascular disease. One had elevated serum antinuclear antibody titers. Pulmonary function data were available for 10 patients: one obstructive, five restrictive, two mixed obstructive and restrictive, and two normal. Computerized tomography in 7 patients showed mosaic attenuation in 3 patients and air trapping in 1 patient; no bronchiectasis, septal lines, or honeycombing were seen in any cases. All 11 patients with available follow-up are alive; 4 of them have experienced symptomatic improvement (follow-up, 0.6-6.9 years; mean, 2.4 years). PBM was found focally in other interstitial lung diseases, which were assessed for this lesion: 59% of usual interstitial pneumonia (17 of 29), 50% of nonspecific interstitial pneumonia (10 of 20), desquamative interstitial pneumonia (3 of 6), hypersensitivity pneumonitis (9 of 18), and 11% of respiratory bronchiolitis (2 of 18). In summary, PBM is a common histologic finding in various interstitial lung disorders. It is rarely the sole major lung biopsy finding in patients presenting with interstitial lung disease (PBM-ILD). Patients are mostly older women, with mild symptoms and CT findings. Survival appears to be favorable.  相似文献   
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