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81.
The effect of the gonadotropin-releasing hormone (LRH) and thyrotropin-releasing hormone (TRH) on the blood levels of LH, FSH and TSH, and LHbeta- and alpha-subunit have been studied in 4 normal subjects during the first 20 min after administration of these releasing hormones. Increases in serum immunoreactive LH, LHbeta and alpha-subunit were seen in all subjects after LRH (100 mug iv) but in all subjects the rise in LH was preceded by a rise in alpha-subunit. All subjects showed an increase in TSH and 3 of the 4 subjects a rise in alpha-subunit after TRH (200 mug) but the alpha-subunit responses were smaller and less consistent than after LRH. Levels of LHbeta remained unchanged after TRH. The results demonstrate that the immunoreactive alpha-subunit of the pituitary glycoprotein hormones can be released independently of the intact hormones and that release occurs in response to the same releasing hormones, LRH and TRH, that release the intact hormones.  相似文献   
82.
We report the cloning and expression of the fifth member of the mammalian UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase (ppGaNTase) family. Degenerate polymerase chain reaction amplification and hybridization screening of a rat sublingual gland (RSLG) cDNA library were used to identify a novel isoform termed ppGaNTase-T5. Conceptual translation of the cDNA reveals a uniquely long stem region not observed for other members of this enzyme family. Recombinant proteins expressed transiently in COS7 cells displayed transferase activity in vitro. Relative activity and substrate preferences of ppGaNTase-T5 were compared with previously identified isoforms (ppGaNTase-T1, -T3, and -T4); ppGaNTase-T5 and -T4 glycosylated a restricted subset of peptides whereas ppGaNTase-T1 and -T3 glycosylated a broader range of substrates. Northern blot analysis revealed that ppGaNTase-T5 is expressed in a highly tissue-specific manner; abundant expression was seen in the RSLG, with lesser amounts of message in the stomach, small intestine, and colon. Therefore, the pattern of expression of ppGaNTase-T5 is the most restricted of all isoforms examined thus far. The identification of this novel isoform underscores the diversity and complexity of the family of genes controlling O-linked glycosylation.  相似文献   
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The normal-state in-plane thermopowerS of superconducting Nd1.85Ce0.15CuO4 (NCCO) crystals has been measured in magnetic fieldsB up to 9 T. When the magnetic field is parallel to the CuO2 planes, we find thatS isB-independent, indicating the absence of spin entropy effects. AsB is oriented perpendicular to the CuO2 planes, a large negative magnetothermopower is found, suggesting an orbital effect which cannot be understood within existing models. A largeT-dependent magnetothermopower is also seen in an as-grown NCCO crystal whenB is perpendicular to the CuO2 planes.We wish to thank P. M. Chaikin, X. C. Xie, and C. Stafford for valuable discussions. This work was supported by NSF under grant No. DMR 9209668.  相似文献   
86.
PURPOSE: Functional outcome after anterior resection for rectal cancer is improved by colonic J-pouch reconstruction compared with straight anastomosis. The indications for colonic J-pouch reconstruction have yet to be determined. Therefore, we attempted to determine the level at which J-pouch reconstruction provides an advantage over straight anastomosis. METHODS: A total of 48 patients who underwent 5-cm colonic J-pouch reconstruction (J-pouch group) and 80 patients who underwent straight anastomosis (straight group) underwent functional assessment one year postoperatively. RESULTS: The functional outcome in the J-pouch group was significantly better than that in the straight group when the distance of the anastomosis from the anal verge was less than 8 cm. The difference was particularly obvious when the level of the anastomosis was below 4 cm. However, functional outcome in the straight group when the anastomosis was between 9 and 12 cm from the anal verge was also satisfactory and did not differ from that in the J-pouch group when the anastomosis was between 5 and 8 cm from the anal verge. CONCLUSIONS: Colonic J-pouch reconstruction is indicated when the distance of anastomosis from the anal verge is less than 8 cm, and it is essential when the distance is less than 4 cm.  相似文献   
87.
For the first time, an international graphics standard is possible. After years of research and redesign, the GKS emerges as the most likely candidate.  相似文献   
88.
The acceptance of new text communication services depends, in part, on whether interworking is possible with other existing or future services. The features of these services are basically determined by their communications protocols. Interworking is to be implemented by automatic facilities located in, or at the boundaries of, the telecommunications networks supporting the services. Aspects of these facilities, known as converters, include centralized versus decentralized siting and implementation, and the mode of operation. In addition, another factor influencing the functions carried out by the converters is the type of interworking. The interworking between the teletex and telex services is discussed as an example.  相似文献   
89.
In recent years, the interest for using biogas derived from biomass as fuel in solid oxide fuel cells (SOFCs) has increased. To maximise the biogas to electrical energy output, it is important to study the effects of the main biogas components (CH4 and CO2), minor ones and traces (e.g. H2S) on performance and durability of the SOFC. Single anode‐supported SOFCs with Ni–Yttria‐Stabilised‐Zirconia (YSZ) anodes, YSZ electrolytes and lanthanum‐strontium‐manganite (LSM)–YSZ cathodes have been tested with a CH4–H2O–H2 fuel mixture at open circuit voltage (OCV) and 1 A cm–2 current load (850 °C). The cell performance was monitored with electric measurements and impedance spectroscopy. At OCV 2–24 ppm H2S were added to the fuel in 24 h intervals. The reforming activity of the Ni‐containing anode decreased rapidly when H2S was added to the fuel. This ultimately resulted in a lower production of fuel (H2 and CO) from CH4. Applying 1 A cm–2 current load, a maximum concentration of 7 ppm H2S was acceptable for a 24 h period.  相似文献   
90.
Directed assembly of nano-particles by charged patterns on an insulator surface is a method that has been applied before, but the creation of the charged patterns was a time consuming process in previous work. Here a scanning electron microscope (SEM) is used to speed up the charging process. The main challenges do not lie in focusing the electron beam but in storing the charge in the insulator in a highly localized way. The present paper shows the first promising results of directing nano-particles to predefined charge patterns on insulators, where the charge is created with a finely focused electron beam. The nano-particles (palladium) are created in an Ar atmosphere with a glowing wire generator (GWG). A narrow size interval of charged particles is selected by a mobility analyzer. From gas suspension they are deposited onto the charge patterns.  相似文献   
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