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731.
Seventy patients with squamous carcinoma or adenocarcinoma of the lung were HLA typed at the time of their diagnosis and initial therapy. No abnormal HLA antigen frequencies were found. However, the possession of HLA-Aw19 or HLA-B5 was significantly correlated with two year disease-free survival. Twelve of 21 patients (57%) with either Aw 19 or B5 were disease-free at two years. In contrast, only six of 48 patients (13%) not having either antigen were disease-free (p less than .001). One patient was lost to follow-up. It is possible that Aw 19 and/or B5 confer resistance to progression of bronchogenic carcinoma on their possessors. 相似文献
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735.
A study was made of advantages and disadvantages of the possible ways of putting the search files of the Canadian Patent Office on microfilm. It was concluded that the best solution would be to use blip coded roll films. 相似文献
736.
M Johnstone 《Canadian Metallurgical Quarterly》1976,31(7):873-882
The arterial hypertension of ketamine is prevented by verapamil, a calcium ion antagonist. This indicates that ketamine is a direct myocardial stimulant acting by increasing the availability of calcium across the cell membranes of the myocardial and the Purkinjé systems. The positive chronotropic action of ketamine is not reversed by verapamil. Both the chronotropic and the inotropic effects of ketamine are prevented by halothane which acts partly by increased vagal tone and partly by what appears to be a verapamil-like depression of calcium availability. Ketamine blocks the reflex sympathetic response of the peripheral blood vessels to surgical stimuli. The site of the block within the sympathetic reflex arc has not been identified. It is not at the alpha adrenoceptor level. The clinical implications of the findings have been discussed. 相似文献
737.
KP Ebmeier SM Lawrie DH Blackwood EC Johnstone GM Goodwin 《Canadian Metallurgical Quarterly》1995,58(4):452-456
Hypofrontality or reduced activity in the prefrontal cortex, measured as reduced frontal perfusion or glucose uptake, has gained the status of an established finding in the medical literature on schizophrenia. Many relevant studies, however, have potential sources of bias, such as small subject numbers, or unreliable performance of activation tasks by the patients during the scanning procedure. Seventy patients with non-affective and non-organic psychoses were recruited--most qualifying for DSM III-R schizophrenia or schizophreniform psychosis (n = 60)--together with 20 healthy volunteers. They underwent single photon emission computed tomography with 99mTc-exametazime, carried out at rest. Tracer uptake was normalised to the occipital cortex. Group differences in tracer uptake were predicted in anterior regions of interest (prefrontal cortex and mesial frontal/cingulate cortex). Actively psychotic (including schizophrenic) patients not taking any drugs showed increased uptake in the prefrontal cortex. Reduced tracer uptake occurred in the mesial frontal cortex of schizophrenic patients, particularly if they were taking drugs. Relatively increased prefrontal tracer uptake associated with relatively decreased mesial frontal uptake characterised the patients in comparison with the controls. Generalised hypofrontality is, therefore, not a feature of schizophrenic patients at rest whether taking drugs or not. 相似文献
738.
Purification and characterization of an interleukin-1beta-converting enzyme family protease that activates cysteine protease P32 (CPP32) 总被引:2,自引:0,他引:2
CPP32, a member of the interleukin-1beta-converting enzyme (ICE) family of cysteine proteases, cleaves poly(ADP-ribose) polymerase and sterol regulatory element binding proteins during apoptosis. CPP32 normally exists in the cytosol as a 32-kDa inactive precursor and only becomes activated when cells are undergoing apoptosis. The activation is a proteolytic event that generates a p20/p11 heterodimer. We report here the identification, purification, and characterization of a hamster CPP32-activating protease (CAP) that cleaves and activates CPP32. The biochemical properties of CAP suggest that it is another member of the ICE family of proteases. Purified CAP consists of two prominent polypeptides of 19 and 13 kDa. Protein sequencing revealed that CAP is derived from the hamster homolog of Mch2alpha, a member of the ICE family recently identified based on the sequence conservation among the ICE family members. CAP activity is inhibited by CrmA, a cowpox virus protein that prevents host cell apoptosis. CAP itself is also activated through proteolytic cleavage. These data are consistent with the idea that the activation of the ICE family of proteases during apoptosis proceeds through a cascade of proteolytic events. 相似文献
739.
Abstract The transmission and cross-coupling characteristics of a surface-plasmon-based polarization beam splitter with multimode interlay between two polished optical fibre blocks are presented. Through the continuous monitoring of the characteristics as a function of interlay refractive index and wavelength it was found that the device is symmetrical in terms of optical power coupling in the cross direction and asymmetrical in terms of transmission, with respect to input launch direction. The fibre fixed in the metal-coated block has a transverse electric (TE) mode transmission which is independent of the refractive index of interlay. The transmission of the other (uncovered) block shows resonance-type interaction for both TE and transverse magnetic modes owing to evanescent field coupling to the multimode interlay. 相似文献
740.
Xiaoping Hu Minh N Luong Hai Zhang Hongshui Zhu Daniel CN Chan 《Journal of Adhesion Science and Technology》2013,27(21):2356-2368
This study aimed to compare the microshear bond strength (MSBS) of three universal adhesives and a three-step conventional adhesive to dentin after 24-hour and one-year storage in water. A new fluoride-releasing universal adhesive (Clearfil Universal Bond Quick: CUQ) and two commercially available adhesives (ScotchBond Universal: SBU and All-Bond Universal: ABU) were evaluated with phosphoric acid etching (PA-etch mode) or without it (self-etch mode). All-Bond 3 (AB3) served as control group. After bonding composite cylinders to dentin discs obtained from caries-free human teeth, the specimens were stored in deionized water at 37?°C for either 24 hours or one year (n?=?14) before MSBS measurement. Two-way ANOVA analysis of the results showed that the adhesives, storage time and their interactions had a significant effect on MSBS (p?<?0.01). In self-etch mode, there was no significant difference among universal adhesives at the baseline. In PA-etch, the CUQ and SBU showed significantly higher MSBS compared with AB3 (p?<?0.05). At baseline, no difference was found between the two modes for each universal adhesive (p?>?0.05). After one year, CUQ in self-etch mode showed a slight increase in nominal MSBS (p?>?0.05) and Weibull characteristic strength, which was significantly higher than SBU and ABU in the corresponding mode. There was no difference among the three universal adhesives in PA-etch mode after one year (p?>?0.05). In conclusion, the durability and reliability of dentin bonding with universal adhesives in different application modes depended on the material; and the self-etch approach showed promising results for the tested fluoride-releasing universal adhesive. 相似文献