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901.
Pro-gastrin-releasing peptide (31-98) as a tumour marker of small-cell lung cancer: comparative evaluation with neuron-specific enolase 总被引:1,自引:0,他引:1
M Takada Y Kusunoki N Masuda K Matui T Yana S Ushijima K Iida K Tamura T Komiya I Kawase N Kikui H Morino M Fukuoka 《Canadian Metallurgical Quarterly》1996,73(10):1227-1232
We attempted to clarify whether serum levels of a carboxy-terminal fragment of ProGRP, ProGRP(31-98), could serve as a more accurate tumour marker in patients with SCLC than neuron-specific enolase (NSE). ProGRP(31-98) and NSE were measured retrospectively in 101 newly diagnosed untreated patients with SCLC, 111 with non-small-cell lung cancer (NSCLC) and 114 patients with non-malignant lung diseases. ProGRP(31-98) and NSE levels were determined using a sandwich enzyme-linked immunosorbent assay. Sensitivity in SCLC patients was 72.3% for ProGRP(31-98) and 62.4% for NSE. Comparing the area under curve (AUC) of 'receiver operator characteristics' of ProGRP(31-98) with that of NSE, ProGRP(31-98) was the more powerful marker in the diagnosis of SCLC (P = 0.0001). Serum levels of ProGRP(31-98) were higher in the 40 patients with extensive disease than in the 61 patients with limited disease (P = 0.0082). ProGRP(31-98) was significantly higher in patients with pure small-cell carcinoma than in patients with mixed small-cell/large-cell carcinoma (P = 0.02). In serial measurement in 16 patients responding to treatment, a high degree of correlation was noted between the decrease in serum ProGRP(31-98) levels and clinical response during the second week after treatment (P = 0.0045). These results indicate that the determination of serum ProGRP(31-98) levels plays an important role in the diagnosis and treatment of SCLC patients. 相似文献
902.
Cloud-to-ground lightning flashes in the Niigata area in Japan have been observed for a few years by a magnetic direction-finder network. Data obtained so far are analyzed carefully taking into account the operating characteristics of the system. As a result, frequency distributions of return-stroke current for each polarity are produced, and their seasonal variations and the occurrence probabilities of high current exceeding 200 kA are clarified. Based on the estimated current distributions, back-flashover rates of 500-kV 2 cct transmission lines are calculated. It is known that the back-flashover caused by downward flashes can account for most of the line outages in the summer for both single- and multiple-line faults. However, this mechanism cannot explain the high outage rate in the winter experienced in the winter thunderstorm area in the late 1970s. In spite of the low lightning flash density in the winter, the multiple-line fault rate in the winter caused by back-flashovers is predicted to be comparable to that in the summer, because of the seasonal variation of the frequency distributions of return-stroke current. 相似文献
903.
24,25-Methylenecholest-5-en-3β-ol, which has not been reported previously to exist in nature, was isolated from mycelia of
an arachidonic acid-producing fungus,Mortierella alpina 1S-4. Desmosterol, ergosta-5,24(25)-dien-3β-ol and ergosta-5,25-dien-3β-ol were also found in the fungus, but ergosterol
and cholesterol were not detected.
On leave from Suntory Ltd. 相似文献
904.
T Komiya Y Kusunoki M Kobayashi T Hirashima T Yana N Masuda K Matsui M Takada K Nakagawa Y Kotake T Yasumitsu M Kikui I Kawase 《Canadian Metallurgical Quarterly》1997,38(5):821-825
Spinal muscular atrophy (SMA) is a frequent autosomal recessive neurodegenerative disorder leading to weakness and atrophy of voluntary muscles. The survival motor neuron gene (SMN) is a strong candidate for SMA and present in two highly homologous copies (telSMN and cenSMN) within the SMA region (5q11.2-q13.3). More than 90% of SMA patients show homozygous deletions of at least exon 7 of telSMN, whereas absence of cenSMN seems to have no clinical consequences. In 23 non-deleted SMA patients, we searched for intragenic mutations of the SMN genes in exons 1-7 and the promotor region by single strand conformation analysis. We identified two different missense mutations, S2621 and T2741, in exon 6 of telSMN in three independent SMA families, providing further evidence for the telSMN gene as a SMA determining gene. Both mutations, as well as two previously described mutations (Y272C and G279V) are located within a highly conserved interval from codon 258 to codon 279 which seems to be an important functional domain of the telSMN protein. Recently, this region has been shown to contain a tyrosine/glycine-rich motif, which is also present in various RNA binding proteins, suggesting a potential role of SMN in RNA metabolism. Missense mutations might be useful for in vivo and transgenic experiments and further investigations on understanding the function of the telSMN protein. 相似文献
905.
906.
The CNDO/2 calculations using the tight-binding approximation for polymers were carried out on poly(trimethylene oxide), (OCH2CH2CH2)n, assuming three crystal modifications, zigzag, orthorhombic, and trigonal forms. The relative stability among the three forms in the polymer was reasonably reproduced by the present calculations. The factors governing the conformational stability were demonstrated. 相似文献
907.
Respiratory failure is an important cause of death in many neuromuscular diseases. We studied the relationship between nocturnal hypoxemia and respiratory muscle weakness by nocturnal pulseoxymetry and spirometry in two major hereditary myopathies, myotonic and Duchenne muscular dystrophies (MD and DMD respectively). In DMD significant nocturnal periodic hypoxemia appears only in cases with vital capacity lower than 20% of its expected value, suggesting that % vital capacity is a useful index of early respiratory failure. In contrast there was no correlation between vital capacity and severity of hypoxemia in MD patients. Therefore, we conclude respiratory muscle weakness is a single important factor which determines the severity of respiratory failure in DMD, while another/other factor (s), such as disturbance of respiratory control or myotonia, may play an important role in MD. 相似文献
908.
Takafumi Shido Takumi Okazaki Maria A. Ulla Toshiyuki Fujimoto Masaru Ichikawa 《Catalysis Letters》1993,17(1-2):97-103
Rh4-xCox(CO)12 (x = 0, 2, 3) are attached by carbonyl substitution to THP (tris-hydroxymethylphospine)-grafted silica keeping their cluster frameworks. They have been characterized by Rh K-edge EXAFS (extended X-ray absorption fine structure) and Fourier transform IR spectroscopy. They exhibited high catalytic activity with > 98% selectivity in gas phase hydroformylation of ethene and propene to give aldehydes under mild conditions (40 kPa and 300–373 K).On leave from Research Center, Arakawa Chemical Industries, LTD, Tsurumi, Osaka 538, Japan.On leave from Department of Chemistry, National University of Literal, Santiago del Estero, 2829-3000, Santa Fe, Argentina. 相似文献
909.
Chromium films deposited by hollow cathode discharge show a variety of hardness, wear resistance and anti-corrosion characteristics. To find the relation between these properties and the film structure, investigations using X-ray diffraction, transmission electron microscopy and Auger electron spectroscopy were carried out for a variety of substrate bias voltages.Films deposited by hollow cathode discharge at 190°C and biased at 0 V and ?50 V and an electrochemically plated hard chromium film were compared by measurements of the Vickers microhardness and the line broadening of the (222)Cr line of X-ray diffraction after vacuum annealing at several temperatures. The hardness is approximately proportional to the square root of the line broadening.All the deposited films show a similar relation between hardness and line broadening. The square root of the grain size of these films as observed by TEM is inversely proportional to the hardness. This relation supports an empirical equation obtained by Agarwal et al. who worked with vacuum-deposited NiCr films. The grain size of the films as observed by TEM is several times larger than that calculated from line broadening. 相似文献
910.
Temperature dependence of elastic stiffness constant C11 was studied from 60 to -100°C by Brillouin scattering and refractive index measurements. It is found that C11 decreases with decreasing temperature over the incommensurate phase and its temperature gradient becomes more or less flat at several degrees above the incommensurate-commensurate transition point Tc, where the dis-commensurate structure appears. This unusual temperature dependence of C11 seems to be attributable to the incommensurately modulated structure of Rb2ZnC14. 相似文献