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81.
Amyloid fibrils derived from the Japanese, Portuguese, and Swedish types of familial amyloidotic polyneuropathy all consist of a variant transthyretin (TTR) with a substitution of methionine for valine at position 30 (TTR Met 30). In an attempt to establish an animal model of TTR Met-30-associated homozygous familial amyloidotic polyneuropathy and to study the structural and functional properties of human TTR Met 30, we generated a mouse line carrying a null mutation at the endogenous ttr locus (ttr-/-) and the human mutant ttr gene (6.0-hMet 30) as a transgene. In these mice, human TTR Met-30-derived amyloid deposits were first observed in the esophagus and stomach when the mice were 11 months of age. With advancing age, amyloid deposits extended to various other tissues. Because no significant difference was detected in the onset, progression, and tissue distribution of amyloid deposition between the ttr-/- and ttr+/+ transgenic mice expressing 6.0-hMet 30, endogenous normal mouse TTR probably does not affect the deposition of human TTR Met-30-derived amyloid in mice. TTR is a tetramer composed of four identical subunits that binds thyroxine (T4) and plasma retinol-binding protein. The introduction of 6.0-hMet 30 into the ttr-/- mice significantly increased their depressed serum levels of T4 and retinol-binding protein, suggesting that human TTR Met 30 binds T4 and retinol-binding protein in vivo. The T4-binding ability of human TTR Met 30 was confirmed by the analysis of T4-binding proteins in the sera of ttr-/- transgenic mice expressing 6.0-hMet 30. The T4-binding studies also demonstrated the presence of hybrid tetramers between mouse and human TTR subunits in the ttr+/+ transgenic mice expressing 6.0-hMet 30.  相似文献   
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84.
We describe two cases of non-Hodgkin's lymphoma associated with t(3;6)(q27;p21.3) and BCL6 rearrangement. The first case was in a 78-year old woman, whose performance status (PS) was 1, the serum lactate dehydrogenase (LDH) level was elevated, and the Ann Arbor stage was IIIA with no extra nodal lymphomatous site. The pathological diagnosis from a biopsy of the inguinal lymph node was 'malignant lymphoma (ML), follicular, small cleaved' according to the Working Formulation. Complete remission was achieved. Although she had relapse in 1992, remission was obtained again. The second case was in a 62-year old man, whose PS was 1, the serum LDH was normal, and Ann Arbor stage was IVA with the involvement of the small intestine. Histological diagnosis of the cervical lymph node was 'ML, diffuse, large cell'. Complete remission was obtained without relapse. The 3q27 translocations, found in 20-30% of non-Hodgkin's lymphoma, are unique in having multiple chromosomal translocation partners. Chromosome band 6p21.3 is one of these partner sites that may be the site of a novel gene. The two cases presented here show that this translocation is a non-random chromosomal change involving 3q27 and BCL6. Since t(3;6) was the sole karyotypic abnormality in one case, this translocation may play a role in lymphomagenesis.  相似文献   
85.
The biopsy specimens were homogenized and diluted ten-fold serially in Hank's solution. Each dilution samples were streaked on Skirrow's selective medium. The plates were incubated at 37 degrees C 5 to 7 days under micro-aerobic condition and counting the viable cell of H. pylori. The positive rate of specimens with H. pylori in active gastric ulcer tissue (62.0%) was higher than that in scarred tissue (51.9%). Number of H. pylori viable cells in active ulcer tissue was significantly larger than in scarred tissue. The positive correlation between Raw's gastritis score of specimens from patients with erosive gastritis and number of H. pylori viable cells was clearly noticed.  相似文献   
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This paper proposes an efficient method to develop requirement specifications for Plant Control Software (PCSW) using software-component-based prototypes. Prior to this proposal, domain analyses were conducted on existing PCSWs, and their functions were classified into “similar functions” and “individual functions”. Then PCSW Software Components (PSC: PCSW Software Component, PSCs: PCSW Software Components) were developed to correspond to these functions. PSCs as parameter-style components were developed in order to satisfy the clients’ (we define clients as owners, managers and operators of plants) requirements. A support environment for developing requirement specifications was developed. The environment consists of the Prototype Development Tool (PDT), the Behavior Check Simulator (BCS) and the Requirement Specification Development Tool (RSDT). The method consists of four steps. In the first step, PDT is used to define the parameters to customize PSCs and to compose a PCSW prototype by setting these parameters to PSCs. In the second step, BCS is used to execute the composed PCSW prototype and check its behavior and relevancy against the clients’ expectations. In the third step, steps 1 and 2 are repeated until the behavior of the PCSW prototype satisfies the clients’ requirements. Finally, a requirement specification is developed from the PCSW prototype which fully reflects the clients’ requirements. In order to evaluate the proposed method, it has been applied in five development cases. A Requirement Coverage of 91%, a Requirement Revision Rate of 6%, a PSC Reuse Rate of 92% and a LOC Reuse Rate of 83% have been achieved. In addition, a reduction of 55% in the amount of time required to develop requirement specifications has been achieved. These results indicate that the proposed method has sufficient capability to develop an exhaustive and an adequate PCSW requirement specification. And the developed PSCs have sufficient functions and capability to compose PCSW prototypes, and the support environment is capable of shortening the time taken to develop requirement specifications.  相似文献   
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Athermal silica-based arrayed-waveguide grating multiplexer   总被引:4,自引:0,他引:4  
A temperature dependent channel wavelength shift in a silica-based arrayed-waveguide grating multiplexer is successfully suppressed from 0.95 to 0.05 nm in the 0-85°C temperature range, which means that it can be used in practical WDM systems without the need for temperature control  相似文献   
90.
A 1-Gb/s/pin 512-Mb DDRII SDRAM has been developed using a digital delay-locked loop (DLL) and a slew-rate-controlled output buffer. The digital DLL has a frequency divider for DLL input, performs at an operating frequency of up to 500 MHz at 1.6 V, and provides internal clocking with 50% duty-cycle correction. The DLL has a current-mirror-type interpolator, which enables a resolution as high as 14 ps, needs no standby current, and can operate at voltages as low as 0.8 V. The slew-rate impedance-controlled output buffer circuit reduces the output skew from 107 to 10 ps. This SDRAM was tested using a 0.13-/spl mu/m 126.5-mm/sup 2/ 512-Mb chip.  相似文献   
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