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91.
This paper focuses on the hydrodynamics of third sound on a superfluid 3 He film. We solve the hydrodynamical equations in the limit of thick films with weak interaction with the substrate. The surface tension at the free interface is shown to have a large effect on the third sound velocity and on the attenuation for frequencies larger than 1Hz. In the case of a diffusely scattering substrate a ripplon-like dispersion relation is found for this frequency range.  相似文献   
92.
In this study, the effect and side-effect of epidural injection with lappaconitine compound for post-operative analgesia was observed. One hundred and twenty patients were randomly divided into 4 groups. Lappaconitine compound (LB) consisted of 12 mg of lappaconitine and 22.5 mg of bupivacaine, was given to group A (the group of observation), and lappaconitine 12 mg, bupivacaine 22.5 mg and morphine 2 mg to group B, C and D respectively for control. All were given by epidural injection with single blind method during post-operative pain of incision operation. Result showed that the initiating of analgesia was quicker in group A and C than that in group B and D, and the efficacy was group D > A > C > B. There was significant difference between group A and B in the above two parameters, P < 0.01 and P < 0.05. The analgisia maintenence time of single injection was D > A > B > C, that of group D was significantly longer than that of group A (P < 0.01). It indicated that the epidural injection with LB was more rapid and potent than that with lappaconitine alone in post-operative analgesia, and the former had no side-effect, it was safer than morphine.  相似文献   
93.
Apolipoprotein E plays a central role in clearance of lipoprotein remnants by serving as a ligand for low-density lipoprotein and apolipoprotein E receptors. Three common alleles (apolipoprotein E(2), E(3) and E(4)) give rise to six phenotypes. Apolipoprotein E(3) is the ancestral form. Common apolipoprotein E isoforms derive from nucleotide substitutions in codons 112 and 158. Resulting cysteine-arginine substitutions cause differences in: affinities for low-density lipoprotein and apolipoprotein E receptors, low-density lipoprotein receptor activities, distribution of apolipoprotein E among lipoproteins, low-density lipoprotein formation rate, and cholesterol absorption. Accompanying changes in triglycerides, cholesterol and low-density lipoprotein may promote atherosclerosis development. Over 90% of patients with familial dysbetalipoproteinaemia have apolipoprotein E(2)/E(2). Apolipoprotein E(4) may promote atherosclerosis by its low-density lipoprotein raising effect. Establishment of apolipoprotein E isoforms may be important for patients with diabetes mellitus and several non-atherosclerotic diseases. Apolipoprotein E phenotyping exploits differences in isoelectric points. Isoelectric focusing uses gels that contain pH 4-7 ampholytes and urea. Serum is directly applied, or prepurified by delipidation, lipoprotein precipitation or dialysation. Isoelectric focusing is followed by immunofixation/protein staining. Another approach is electro- or diffusion blotting, followed by protein staining or immunological detection with anti-apolipoprotein E antibodies and an enzyme-conjugated second antibody. Apolipoprotein E genotyping demonstrates underlying point mutations. Analyses of polymerase chain reaction products are done by allele-specific oligonucleotide probes, restriction fragment length polymorphism, single-stranded conformational polymorphism, the primer-guided nucleotide incorporation assay, or denaturating gradient gel electrophoresis. Detection with primers that either or not initiate amplification is performed with the amplification refractory mutation system. Disparities between phenotyping and genotyping may derive from isoelectric focusing methods that do not adequately separate apolipoprotein E posttranslational variants, storage artifacts or faint isoelectric focusing bands.  相似文献   
94.
A review of isolates of Neisseria meningitidis and other laboratory evidence of meningococcal infection was carried out for the period 1990-1995. Thirty-three patients with evidence of meningococcal disease were identified over the six year period. Group B organisms were the most commonly identified, but an increase in Group C has occurred and is almost equal in number. Data from clinical, laboratory and public health sources should be centralized in a National Surveillance Centre.  相似文献   
95.
14 medicated hypertensive, 15 nonmedicated mild hypertensive, 39 normotensive, and 13 hypotensive adults participated in a 1–2 hr laboratory experiment that assessed each S's symptoms, moods, and estimates of systolic blood pressure (SBP) relative to actual SBP levels. Several self-reports and autonomic measures were collected during and after each of 22 tasks. Within-S correlations indicated that all Ss could estimate SBP at levels greater than chance. Further, 68% of the Ss evidenced at least 1 significant symptom–SBP correlation. Although medicated hypertensives believed they could estimate their BP more accurately than other groups, they were actually no more accurate than the other Ss. They also evidenced far fewer empirically derived symptom–SBP and emotion–SBP correlations than any other group. Overall, blood pressure (BP) beliefs were largely inaccurate. If these erroneous beliefs can be eliminated, Ss may be able to estimate BP fluctuations more accurately. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
97.
In this paper, a physics-based mismatch model is presented. It is demonstrated on a 0.18-/spl mu/m technology that a simple mismatch model can still be used to characterize deep-submicron technologies. The accuracy of the model is examined and found to be within 20% in the strong inversion region. Bulk bias dependence is modeled in a physical way. To extract the mismatch parameters, a weighted fit is introduced. It is shown that the width and length dependence of the mismatch parameters is given by the Pelgrom model.  相似文献   
98.
An attack on the public key cryptosystem Polly Cracker is described, that reveals the complete secret key σ ∈ Fq n by means of n (nonadaptively) chosen "fake" ciphertexts  相似文献   
99.
Using AuGeNiCr multilayered metals as the wafer bonding medium, long-wavelength GaInAsP/InP vertical cavity surface emitting lasers employing Al-oxide/Si as the upper and lower distributed Bragg reflectors were fabricated on Si substrate with the bonding interface formed outside the vertical cavity surface emitting laser cavity. Laser emission at 1.545 μm was measured under pulsed operations near room temperature. The low-temperature metallic bonding process demonstrates a great potential in device fabrication  相似文献   
100.
The airborne Millimeter-wave Imaging Radiometer (MIR) measurements conducted over the Midwest region of the continental United States during January/February 1997 and over the Alaska-Arctic region during May 1998 are used to estimate column water vapor W<0.8 g/cm/sup 2/ under a clear sky. On board the same aircraft are two other instruments, the Cloud Lidar System (CLS) and MODerate-resolution Imaging Spectrometer (MODIS) Airborne Simulator (MAS), which provide cloud cover information and independent measurements of W, respectively. The MIR-estimated W values are compared and found to be in very good agreement with those measured by rawinsondes at near concurrence. A close correlation is found between the MIR-estimated W and that estimated from the MAS near-IR reflectance ratios. Water surface emissivities at several MIR frequencies are obtained in the process of the W retrieval from several flights over the Midwest lakes. These estimated emissivities compared favorably with values calculated for a calm water surface, which are based on a di-electric permittivity model and MAS-measured surface temperatures. The results from all comparisons strongly demonstrate the soundness of the technique for estimating W.  相似文献   
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