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91.
BACKGROUND: Recent studies have suggested that the nervous system may participate in inflammatory processes. Substance P (SP) acts as a chemical mediator as well as a neurotransmitter. OBJECTIVE: In order to clarify the pathogenesis of ocular allergic diseases, we assessed the concentration of SP in tears. METHODS: Using a highly sensitive and specific double-antibody enzyme immunoassay (EIA), we determined the SP concentration in tears of 10 patients with seasonal allergic conjunctivitis, 10 with atopic dermatitis without keratoconjunctivitis (AD), 13 with vernal keratoconjunctivitis (VKC) and 65 normal controls. Giemsa's staining for brush cytology samples and histocytological study by immunocytochemical staining of giant papillary conjunctival cells from VKC and normal controls was conducted. RESULTS: The mean SP level was low in the normal controls and AD, whereas patients with seasonal allergic conjunctivitis and VKC showed significant elevation of SP (P < 0.01). Brush cytology samples showed conjunctival epithelial cells with lymphocytes, neutrophils and eosinophils that were not seen in normal subjects. Histocytological examination demonstrated SP positive cells in the conjunctiva of patients with VKC, but not in normal controls. CONCLUSION: This study suggests that the increased level of SP in tears may contribute to the pathogenesis and severity of ocular allergic diseases.  相似文献   
92.
A dual-mode sensing (DMS) scheme for a capacitor-coupled EEPROM cell is described. A memory cell structure and a sensing scheme are proposed and estimated. The memory cell combines an EEPROM cell with a DRAM cell. The DMS scheme utilizes the charge-mode sensing of the EEPROM cell. Using this DMS technique, the sensing speed can be enhanced by 36% at a cell current of 15 μA by virtue of the additional charge-mode sensing. Furthermore, the stress applied to the tunnel oxide of the memory transistor can be relieved by decreasing the programming voltage and shortening the programming time. Therefore, with this memory cell structure and sensing scheme, it is possible to realize high-speed sensing in low-voltage operation and high endurance  相似文献   
93.
94.
To clarify the ability of endoscopic ultrasonography (EUS) to diagnose gastric ulcer, we induced gastric ulcer (19 open ulcers and 11 ulcer scars) by injecting acetic acid into the stomach via an endoscope in 15 dogs. The stomachs were resected and scanned by EUS in a water bath, and the findings were compared with the histologic observations. The ulcer depth was correctly diagnosed in 29 of 30 instances (96.7%). In active, open ulcers the width and depth of the ulcer crater and the thickness of the gastric wall around the crater measured in the photographs obtained by EUS corresponded with those observed in histologic photographs. In the ulcers disrupting the muscularis propria layer the distance between the disrupted muscularis propria layer in EUS also corresponded to the histologic observations. In all ulcer lesions the low-echoic area below the ulcer in EUS corresponded to the histologic area of granulation or fibrosis. However, it was difficult to distinguish granulation from fibrosis by EUS. EUS is thus considered useful for evaluating gastric ulcers quantitatively in the clinical setting.  相似文献   
95.
The authors studied mortality from major causes of death and risk factors in the elderly in a long-term prospective survey conducted in a Japanese suburban community, Hisayama. In the baseline survey in 1961, we scrutinized 1658 residents of the town aged 40 years or older accounting for 92% of the total population in this age range. Of those, 591 residents (245 men and 346 women) aged 60 years or older, who were free from major cardiovascular disease, were selected for the present study. They were followed-up for 26 years from 1961 to 1987. The average age was 67 years for men and 70 years for women, being significantly higher for women than for men. During the follow-up period, 529 subjects (89.5%) died, and 448 were autopsied (autopsy rate 84.7%). The all-cause mortality (per 1,000 person-years) after adjustment for age was 89.9 for men and 56.7 for women, the former being significantly higher than the latter (p < 0.01). The age-adjusted mortality from cerebrovascular disease was estimated to be 21.4 for men and 9.9 for women, i.e. 8.9 and 8.8 from heart disease, and 19.9 and 10.6 from neoplasm, and 18.1 and 12.2 from-pneumonia, respectively. There was significant sex difference in mortality from cerebrovascular disease, neoplasm and pneumonia (p < 0.01) but not from heart disease (p > 0.1). Multiple Cox's proportional hazards regression analysis showed systolic blood pressure and male sex to be significant risk factors for death by cerebrovascular disease. Systolic blood pressure was also a predictor for death by heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
96.
Comparison of the clinical features, especially prognosis, in cerebral infarction was made between nine normotensive subjects and 16 hypertensive patients with an 80% stenosis or occlusion of the intracranial or extracranial arteries. Our own criteria for evaluating hypertension were employed on the basis of the following items: a past history of hypertension, blood pressure levels on admission and during hospitalization, degree of retinopathy, and ECG changes. In 17 of 25 cases, brain circulation was measured by the intravenous RISA technique. Abnormalities of the EEG and reduction of cranial blood flow were greater, and an early prognosis for neurological deficits in the first two months after the onset of stroke was poorer in the hypertensive group than inthe normotensive group. These results are contradictory to the observations of others.  相似文献   
97.
We measured mean blood flow velocity (MFV) and Fourier pulsatility index (PI) of the M1 portion of the middle cerebral artery (MCA) by transcranial Doppler mapping technique (2 MHz, Trans-scan, EME Co., Ltd.). The correlations between these parameters and arteriosclerotic risk factors such as aging, hypertension and diabetes mellitus were examined. Healthy volunteers as well as patients suffering from hypertension and diabetes mellitus were studied. A total of 59 persons (85 MCAs) consisting of 30 males (mean age 54.4, 24-81 years) and 29 females (mean age 54.8, 20-75 years) were enrolled in this study. Some hypertensive or diabetic subjects had previous cerebrovascular disease, therefore cases who had only minor stroke or asymptomatic infarction without significant lesions in carotid artery system were included. After excluding brain embolism, these subjects were divided into three groups as normotensive/non diabetic group (NT/non DM), hypertensive group (HT) and diabetic group (DM). In each group, MFV decreased with aging, being more evident in the HT and DM groups than in the NT/non DM group. Fourier PI also showed a significant increase with aging, and the correlation was stronger than that between MFV and age. Moreover, these trends of age-Fourier PI relationship were more highly significant in HT and DM groups than NT/non DM group. In cases with HT or DM, age-related arterial changes appeared to be more severe than in those without. Fourier PI seemed valuable for detecting arterial lesions with aging, HT and DM.  相似文献   
98.
Photo-induced radicals in glucose and cellobiose, the model compounds of cellulose molecule, were studied by ESR spectrometry. Very poor formation of radicals in glucose as compared to those in cellobiose was observed. However, a spectrum showing a singlet line was easily produced by the use of light involving shorter wavelengths. It was estimated to be due to the radical formed at the reducing C1 position of glucose molecule. By paper chromatography, the photo-irradiated cellobiose was confirmed to split into glucose through scission of glucosidic bonds in the molecule. The ESR spectrum of the acid-hydrolyzed cellulose similar to that of the unhydrolyzed sample was a seven-line spectrum, but the relative signal intensity was here markedly low. This phenomenon seems to be caused by the reduction of amorphous portion in the samples due to acid hydrolysis. It was concluded that the glucosidic bonds in cellobiose and cellulose molecules are very active toward light and play an important role in the radical formation in photo-irradiated samples.  相似文献   
99.
Shiina T  Yoshida K  Ito M  Okamura Y 《Applied optics》2005,44(34):7407-7413
An in-line type compact micropulse lidar (MPL) with an annular beam was developed for low-altitude cloud measurement. An optical circulator and a couple of axicon prisms for an annular beam were installed on the lidar optics. The advantage of using the in-line MPL is its ability to obtain a near-range measurement with a narrow field of view of 0.1 mrad and to obtain a depolarization measurement of the orthogonally polarized echoes caused by ice crystals of a low-altitude cloud. The total insertion loss of the lidar optics was 3 dB. Detectors such as avalance photodiode detectors can be operated in an analog mode near the breakdown voltage because of the high isolation of the optical circulator. The ideal lidar echo variation from the nearest distance was verified by measuring the mountain echoes at various distances. The depolarization measurement of a low-altitude ice cloud was also demonstrated.  相似文献   
100.
Fundamental photocatalytic behaviors were investigated for mechanical mixtures of TiO2 crystalline particles (P25) and MFI type zeolite (silicalite) in the decomposition reaction of 2-propanol vapor in air for the first time. Mechanical mixing enables reliable comparisons to be made between photocatalysts because the contents of TiO2 and the adsorbent can be widely varied (51 times in this study) while keeping the particle size and crystallinity of TiO2 unchanged. That is, the use of mechanical mixture highlights the behavior of molecules adsorbed in the microporous crystals, keeping the TiO2 unchanged. In the case of the mixed photocatalysts, the initial 2-propanol concentration in the gas phase was significantly reduced because of adsorption into the zeolite. After photo-irradiation started, 2-propanol was decomposed to CO2 with no (or trace amount of) acetone detected in the gas phase. The analysis of final amount of CO2 formed by the decomposition demonstrated that just by the mechanical mixing of TiO2 and zeolite, the TiO2 photocatalyst decomposed completely the reactant and intermediate molecules strongly adsorbed into the zeolite. On the other hand, in reference experiments in which TiO2 and zeolite were not mixed and were separately placed in a photoreactor, the organic compounds strongly adsorbed in the zeolite could not be decomposed to CO2 by the photocatalyst. It is notable that the CO2 formation rates for the mixed photocatalysts were mostly constant for those comprising 40 wt% or larger amounts of zeolite, while being slower than for pure TiO2. The rate-determining step was discussed based on these data. The present study showed that the mixed photocatalyst could remove organic vapors by adsorption in the dark and decompose completely to CO2 at moderate reaction rates under photo-irradiation with minimized evolution of intermediate molecules into the gas phase.  相似文献   
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