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91.
92.
Isoelectric focusing of whole saliva samples on polyacrylamide gels (pH 3.5-5), followed by dried agarose film overlay detection, was employed to determine the type of salivary deoxyribonuclease I (DNase I). Since this detection method had not only a high sensitivity, but also a high band resolution, it was possible to determine DNase I types from saliva samples of 2-5 microL. Pretreatment of saliva samples with neuraminidase simplified the isozyme pattern and enhanced the sensitivity. The DNase I types in all 30 saliva samples showed a good correlation with the types found in the corresponding blood, semen, and urine samples. This preliminary trial indicates that DNase I typing from saliva samples is a new and promising method for individualization of casework samples in the field of forensic biology.  相似文献   
93.
BACKGROUND: Microvascular angina can occur during exercise and at rest. Reduced vasodilator capacity of the coronary microvessels is implicated as a cause of angina during exercise, but the mechanism of angina at rest is not known. Our aim was to test the hypothesis that primary hyperconstriction (spasm) of coronary microvessels causes myocardial ischaemia at rest. METHODS: Acetylcholine induces coronary artery spasm in patients with variant angina. We tested the effects of intracoronary acetylcholine at graded doses in 117 consecutive patients with chest pain (at rest, during exertion, or both) and no flow-limiting (>50%) organic stenosis in the large epicardial coronary arteries. We also assessed the metabolism of myocardial lactate during acetylcholine administration in 36 of the patients by measurement of lactate in paired blood samples from the coronary artery and coronary sinus vein. FINDINGS: Of the 117 patients, 63 (54%) had large-artery spasm, 29 (25%) had microvascular spasm, and 25 (21%) had atypical chest pain. The 29 patients with microvascular spasm developed angina-like chest pain, ischaemic electrocardiogram (ECG) changes, or both spontaneously (two patients) or after administration of acetylcholine (27 patients) without spasm of the large epicardial coronary arteries. Testing of paired samples of arterial and coronary sinus venous blood showed that lactate was produced during angina attack in nine of 11 patients with microvascular spasm. There was more women (p<0.01) and fewer coronary risk factors (p<0.01) in patients with microvascular spasm than in those with large-artery spasm. INTERPRETATION: Coronary microvascular spasm and resultant myocardial ischaemia may be the cause of chest pain in a subgroup of patients with microvascular angina.  相似文献   
94.
Ryoichi Kikuchi 《Calphad》1985,9(4):311-348
A computer program for calculating the disorder-order phase diagrams of FCC-based binary alloys is presented. The cluster variation method is used, with the tetrahedron as the basic cluster. Ordered phases are the Cu3Au type (L12) and the CuAu type (L10). Energy parameters are independent of temperature and composition, and include the many-body effect within a tetrahedron. A detailed explanation of the computer program is presented in the main body of the paper. Three example calculations are shown.  相似文献   
95.
96.
Sixteen Holstein cows in midlactation were used in a design based on a replicated 4 x 4 Latin square with the last period removed to determine the influence of particle size of beet pulp neutral detergent fiber (NDF) on its effectiveness as a replacement for alfalfa NDF. Diets were a low forage, low fiber diet [12.1 g of alfalfa NDF/100 g of dry matter (DM)], a normal forage diet (low forage plus 7.8 g of additional alfalfa NDF/100 g of DM), and two low forage diets with 5.3 g of NDF/100 g of DM from either whole or finely ground dried sugar beet pulp. Replacement of alfalfa fiber with beet pulp fiber increased milk protein yield because of the tendencies toward increased milk yield and protein concentration. However, milk fat concentration and yield were unaffected. The addition of beet pulp fiber, either whole or ground, to the basal low forage, low fiber diet did not affect yields of milk, protein, or fat, but milk protein concentration tended to be lower for cows fed the beet pulp diets than for cows fed the basal diet. Reducing the particle size of beet pulp increased DM intake but did not affect any of the milk yield measurements. Particle size reduction of beet pulp did not reduce its effectiveness as a fiber source as measured by changes in milk fat content.  相似文献   
97.
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   
98.
We developed experimental procedures to evaluate glass materials using the line-focus-beam ultrasonic-material-characterization (LFB-UMC) system. We prepared 28 specimens of a commercial borosilicate glass from random lots, and measured the velocities of leaky-surface acoustic waves (LSAWs) and leaky-surface-skimming compressional waves (LSSCWs), VLSAW and VLSSCW, using V(z) curve measurements at 225 MHz and 23 degrees C. The velocities for VLSAW ranged from 3121.83 m/s to 3149.77 m/s, with a maximum deviation of 27.94 m/s. The velocities for VLSSCW ranged from 5547.7 m/s to 5585.0 m/s, with a maximum deviation of 37.3 m/s. To investigate these observed variations in VLSAW and VLSSCW, we measured the bulk acoustic wave (BAW) properties, viz., longitudinal and shear velocities, then the densities and the chemical compositions of 8 of the 28 specimens. The LFB-UMC measurements confirmed that decreases in VLSAW and VLSSCW occur mainly with the B2O3 dopant concentrations, corresponding to the decrease of shear-wave and longitudinal-wave velocities that are caused by the decrease of the stiffness constants c44 and c11, respectively, rather than with decreased densities. The sensitivities are -6.36 x 10(-2) wt%/(m/s) for VLSAW and -4.87 x 10(-2) wt%/(m/s) for VLSSCW. This demonstrates that the LFB-UMC system is effective for evaluating glass materials and controlling production processes, by analyzing variations in chemical composition through the super-accurate velocity measurements of LSAWs and LSSCWs.  相似文献   
99.
Microscopic observation of carbons obtained from pure aromatic hydrocarbons by the aid of carbonization catalysts was carried out to clarify the microstructure of these carbons of different features. Reflected polarized-light microscopy distinguished needle, mosaic and isotropic cokes, former two of which were produced with aluminum chloride and the last with potassium. High resolution microscopy revealed that these carbons calcined at 1250° had different degree of layered structure, corresponding to the crystallographic parameters of these samples graphitized at 2500°C. The reasons for the carbons produced with potassium to be non-graphitizable are discussed from the macro- and micro-features of the carbons.  相似文献   
100.
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