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151.
A case of thoracoscopic right lower pulmonary lobectomy is reported. A 79-year-old man was admitted to our hospital after the accidental finding of a right pulmonary growth. A computed tomography (CT) scan of the thorax confirmed the presence of a neoplasm, 2.5 cm in diameter, at the posterior-basal segment of the right lower lobe. Considering the general condition of the patient and the characteristics of the lesion, we decided to perform a assess the possibility of a thoracoscopic lobectomy instead of the traditional posterolateral approach. The pulmonary artery was dissected with the new endoscopic cherry dissector, and ligated with the polyester suture material and Endo Clip then dived with Endo scissors. The lower pulmonary vein was dissected with this endoscopic cherry dissector and divided with Endo GIA 30 clamping the new thoracoscopic De Bakey type vascular clamp. The specimen was extracted through the minimal thoracotomy (15 cm). The postoperative course was uneventful with minimal postoperative pain, and the patient was discharged after complete surgical recovery with excellent functional and cosmetic results.  相似文献   
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Pyriform sinus cyst and fistula is a relatively rare tumor of the neck, even less is the neonatal period. We experienced a case of this one, and preoperative diagnosis was made by using endoscopy and cine-esophagography. A dyeing method that confirmed the fistula tract of cyst lead us to successful resection.  相似文献   
154.
A CMOS pipelined floating-point processing unit (FPU) for superscalar processors is described. It is fabricated using a 0.5 μm CMOS triple-metal-layer technology on a 61 mm2 die. The FPU has two execution modes to meet precise scientific computations and real-time applications. It can start two FPU operations in each cycle, and this achieves a peak performance of 160 MFLOPS double or single precision with an 80 MHz clock. Furthermore, the original computation mode, twin single-precision computation, double the peak performance and delivers 320 MFLOPS single precision. Its full bypass reduces the latency of operations, including load and store, and achieves an effective throughput even in nonvectorizable computations. An out-of-order completion is provided by using a new exception prediction method and a pipeline stall technique  相似文献   
155.
The genetic defect in a patient with hereditary type I protein S (PS) deficiency was investigated. All the exons and intron-exon junctions of the patient's PS gene were amplified by PCR and subjected to heteroduplex screening. Only the PCR product of exon 4 revealed heteroduplex bands. A novel nonsense mutation, Ser62 (TCA) to Stop (TGA) was found in exon 4. RT-PCR detected the aberrant mRNA in the patient's platelets, which was markedly reduced in amount and lacked the region of exon 4, suggesting that the nonsense mutation affected the mutated mRNA metabolism and induced exon skipping. The skipping of exon 4 causes an in-frame deletion of 29 amino acids which just construct the thrombin-sensitive region of the PS molecule. The loss of such an important domain as well as the quantitative decrease in the mutated mRNA appear to be responsible for the type I PS deficiency in this patient.  相似文献   
156.
Requirements for a terrestrial ISDB system and the schemes for efficiently using frequencies to fulfil the requirements are discussed. One requirement of a terrestrial ISDB system is the efficient allocation of frequencies using a SFN (single frequency network). The SFN incorporates the great advantages of OFDM, which has excellent performance under multi-path conditions. The transmission characteristics of 64QAM-OFDM and the SFN capability using 64QAM-OFDM in the Kanto area, including the Tokyo metropolitan area, are analyzed. The results show that more than a 97% coverage ratio can be obtained even by using a single channel while the same area is covered currently by more than 30 analog channels. The other requirement is a scheme for efficiently using the available frequency band for various services. A transmission scheme concept called BST-OFDM (band segmented transmission-orthogonal frequency division multiplexing) is proposed as a transmission scheme for meeting the requirements of a terrestrial ISDB system. In the BST-OFDM scheme, data are transmitted in a number of OFDM blocks called a BST-segment, for which channel coding and modulation schemes can be independently defined to provide robustness in the transmission environment according to stationary, portable and mobile reception  相似文献   
157.
The PCR copy of the ribR gene of Bacillus subtilis was subcloned in Escherichia coli cells under the control of the phage T7 inducible promoter. The polypeptide of 26 kDa corresponding to the 690-bp gene is the product of the ribR gene. The protein encoded by the ribR gene is flavokinase, and the riboflavin-reduced form is the substrate for it.  相似文献   
158.
A ceramic/metal nanocomposite in tetragonal zirconia-molybdenum system possesses a novel microstructural feature composed of a mutual intragranular nanostructure, in which either nanometer sized Mo particles or equivalent sized zirconia particles are located within the zirconia grains or Mo grains, respectively. It achieves a simultaneous improvement in strength and toughness that overcomes the strength-toughness tradeoff relation.  相似文献   
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