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Deficiency of the ninth component of complement (C9D) is one of the most common genetic abnormalities in Japan, with an incidence of one homozygote in 1000. Although C9D individuals are usually healthy, it has been shown that they have an significantly increased risk of developing meningococcal meningitis. In the present study we report the molecular bases for C9D in 10 unrelated Japanese subjects. As a screening step for mutations, exons 2 to 11 of the C9 gene were analyzed using exon-specific PCR/single-strand conformation polymorphism analysis, which demonstrated aberrantly migrating DNA bands in exon 4 in all the C9D subjects. Subsequent direct sequencing of exon 4 of the C9D subjects revealed that eight of the 10 C9D subjects were homozygous for a C to T transition at nucleotide 343, the first nucleotide of the codon CGA for Arg95, leading to a TGA stop codon (R95X). R95X is a novel mutation different from those recently identified in a Swiss family with C9D. Cases 6 and 7 were heterozygous for the R95X mutation. Family study in case 10 confirmed the genetic nature of the defect. In case 6, the second mutation for C9D of the C9 gene was identified to be the substitution of Cys to Tyr at amino acid residue 507 (C507Y), while the genetic defect(s) in the other allele in case 7 remains unknown. Our results indicate that a novel mutation, R95X, is present in most cases of C9D in Japan.  相似文献   
64.
A novel surface-emitting light-emitting diode (LED)/laser diode (LD) with a coaxial transverse junction (CTJ) structure is demonstrated by modified structures of the well and hole types with improved thermal properties. A narrow emission pattern for the LED was realised due to the CTJ structure and preliminary results for laser operation were also obtained at low temperatures  相似文献   
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The maximum biting force in 82 male athletes and 12 male subjects without any particular athletic activity (nonathletes) were measured in order to evaluate the relationship between biting force and physical fitness in athletes. The results obtained were as follows. 1. The maximum biting force in athletes (50.8 +/- 17.4kg) were significantly (p < 0.01) higher than that in the nonathletes (28.1 +/- 9.1kg). The maximum biting forces in the men who belonged to the rugby or judo clubs were predominantly higher than in other subjects. 2. In men who masticated on the left side of the mouth, the habitual (i. e., left) biting force was significantly higher than the nonhabitual (i. e., right) biting force. In men who masticated on the right side of the mouth, the habitual (i. e., right) biting force was also higher than the nonhabitual (i. e., left) biting force, but was not significantly so. 3. There was a significant positive correlation between the biting force and grip strength and back strength in athletes. In athletes, there was a significant correlation between biting force and the numbers of chin-ups, the numbers for the side-step tests and the time for 50m running.  相似文献   
67.
This paper presents an experimental investigation of convective heat transfer in a confined rectangular cavity packed with porous media, on the opposing vertical walls of which different temperatures are imposed. Measurements are made for each of two kinds of solid particles using three kinds of fluids, i.e. water, transformer oil and ethyl alcohol. The present experiments cover a wide range of Rayleigh number Ra1 between 1 and 105, Prandtl number Pr1 between 1 and 200 and geometrical aspect-ratio HW between 5 and 26. The experimental results indicate that Nusselt number Nu1 is correlated by the following relationship: Nu1 = 0.627 Pr10.130 (HW)?0.527 Ra10.463  相似文献   
68.
A large-scale solar pond with salty water was constructed in the suburbs of Kitami in 1985. Its performance has been measured and analyzed by the authors after that. The solar pond body is circular of 44 m diameter, and the pond water is of 3 min total depth. After, 15 months, the depth of the salt gradient zone (S.G.Z.) was thinned by 10 cm in the top and by 20 cm in the bottom due to convection of the top and bottom zones. The temperature in the convective storage zone (C.S.Z.) reached 70°C, its maximum, at the beginning of September in 1985, however, it was not as high in 1986 due to contamination of the pond water. The temperature of the storage zone was reduced from November to April due to ice covering on the pond surface. The collected heat yielded largely and the collection efficiency reached more than 30% in summer, but decreased to negative values in winter. The thermal performance of the solar pond was predicted by a simulation calculation, and the calculated result compared well with the measurements.  相似文献   
69.
PURPOSE: To report initial clinical experience with a novel high-precision stereotactic radiotherapy system. METHODS AND MATERIALS: Sixty patients ranging in age from 2 to 82 years received a total of 1426 treatments with the University of Florida frameless stereotactic radiotherapy system. Of the total, 39 (65%) were treated with stereotactic radiotherapy (SRT) alone, and 21 (35%) received SRT as a component of radiotherapy. Pathologic diagnoses included meningiomas (15 patients), low-grade astrocytomas (11 patients), germinomas (9 patients), and craniopharyngiomas (5 patients). The technique was used as means of dose escalation in 11 patients (18%) with aggressive tumors. Treatment reproducibility was measured by comparing bite plate positioning registered by infrared light-emitting diodes (IRLEDs) with the stereotactic radiosurgery reference system, and with measurements from each treatment arc for the 1426 daily treatments (5808 positions). We chose 0.3 mm vector translation error and 0.3 degrees rotation about each axis as the maximum tolerated misalignment before treating each arc. RESULTS: With a mean follow-up of 11 months, 3 patients had recurrence of malignant disease. Acute side effects were minimal. Of 11 patients with low grade astrocytomas, 4 (36%) had cerebral edema and increased enhancement on MR scans in the first year, and 2 required steroids. All had resolution and marked tumor involution on follow-up imaging. Bite plate reproducibility was as follows. Translational errors: anterior-posterior, 0.01 +/- 0.10; lateral, 0.02 +/- 0.07; axial, 0.01 +/- 0.10. Rotational errors (degrees): anterior-posterior, 0.00 +/- 0.03; lateral, 0.00 +/- 0.06; axial, 0.01 +/- 0.04. No patient treatment was delivered beyond the maximum tolerated misalignment. Daily treatment was delivered in approximately 15 min per patient. CONCLUSION: Our initial experience with stereotactic radiotherapy using the infrared camera guidance system was good. Patient selection and treatment strategies are evolving rapidly. Treatment accuracy was the best reported, and the treatment approach was practical.  相似文献   
70.
We report three cases in which continuous intra-arterial infusion therapy via the occipital artery was combined with radiotherapy for head and neck tumors. An angiographic catheter was inserted into the feeding artery of the tumor retrogradely via the occipital artery under fluoroscopic guidance. Patients treated were maxillary sinus cancer, tongue cancer and hemangiosarcoma. No complications occurred due to this procedure in any of the three patients. This procedure was considered very useful when the approach from the superficial temporal artery was not possible due to prior treatment.  相似文献   
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