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961.
962.
This paper describes the physical design and characteristics of FS-400M submarine optical repeater housing which has the ability to withstand the severe deep-sea environment for more than 25 years. In this repeater housing, a heat-dispersive and shock-absorbing structure using Al powder mixtured rubber cushion and metal fin, an optical and power feedthrough using epoxy resin and solder, a caulking-type cable termination with multi-hole sleeve, and a completely insulated joint chamber located in a cable coupling are developed.  相似文献   
963.
Enhanced US by intraarterial infusion of CO2 microbubbles is useful for segmental to subsegmental TAE of hepatocellular carcinoma for several reasons. First, we can obtain better recognition of the tumor stain of hepatocellular carcinoma which is even faint on DSA. Secondly, we can recognize the co-relation between tumor stain and its related segment or subsegment well. Therefore, subsegmental or segmental TAE can be performed easily and precisely using enhanced US by CO2 microbubbles. We noted the bigger advantage of enhanced US by CO2 microbubbles especially in the repeated treated cases of TAE for hepatocellular carcinoma.  相似文献   
964.
Donor-site complications, specifically chest wall deformities and thoracic scoliosis, occurring after harvest of costal cartilage grafts are presented and discussed. The cases of 18 patients (12 male and 6 female), who underwent costal cartilage grafts for microtia reconstruction from 1975 to 1993, were reviewed for donor-site complications using radiography and physical examination. Ribs from which costal cartilage had been harvested showed increased inward bowing on radiographs in 16 of 32 donor sites. The frequency of rib deformity in donor sites was 20.0 percent when cartilages were harvested from patients older than 10 years of age, whereas it was 63.6 percent in patients younger than 10 years old. This difference was statistically significant (p = 0.027, Fisher's exact test), although only 32 grafts were performed in 18 cases. The upper ribs demonstrate a higher incidence of deformity than lower ribs. Thoracic scoliosis was found in 4 of 16 cases. The biomechanical impact of these deformities was considered because of respiratory movement of the thorax and injury to the germinal growth center of the ribs. We recommend delaying costal cartilage grafts for as long as possible, leaving the costochondral junction intact to minimize chest wall deformity and thoracic scoliosis.  相似文献   
965.
We describe a case of left femoral neck fracture associated with multicentric reticulohistiocytosis (MR). Biopsy specimens from a skin nodule and from synovial tissue showed histiocytic multinucleated giant cells (MR cells) that are characteristic of MR. A surgical specimen from the resected femoral head revealed that multinucleated giant cells and mononuclear cells invaded the marginal subchondral bone, without evident pannus. These cells also infiltrated into the fracture site, with bone resorption by activated osteoclasts. Immunohistochemical studies of synovium from the left hip joint showed positive staining for interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor alpha, and abundant cytokine production by cultured synovial cells was demonstrated. These findings suggest that the subchondral invasion and intramedullary infiltration by MR cells caused articular destruction and/or fracture as a result of oversecretion of the cytokines.  相似文献   
966.
We investigated the effects of the presence or absence of N2O in propofol anesthesia using a laryngeal mask on the incidence of postoperative sore throat. In the N2O-combined anesthesia group (n = 25), score 0 (no sore throat) was observed in 11 patients; score 1 (slight pain and discomfort that improved on the next day of operation) in 9; and score 2 (persistent pain on the next day) in 5. In the non-N2O-combined anesthesia group (n = 25), score 0 was observed in 21 patients, score 1 in 3; and score 2 in 1, showing a significantly lower incidence of sore throat and milder sore throat than in the N2O-combined anesthesia group. These results suggest that propofol anesthesia using a laryngeal mask not combined with N2O reduces the incidence of postoperative sore throat.  相似文献   
967.
Aerostatic thrust bearings have been used in linear guideway systems of various precision measuring apparatus by reasons of low friction, non-hysteresis and high accuracy of motion. In such a case that the measuring systems do not satisfy the Abbé principle, the accuracy of linear guideway systems is greatly influenced by the tilt characteristics in pitch, roll and yaw directions of aerostatic thrust bearings. This paper proposes the application of aerostatic rectangular double-pad thrust bearings with double row admissions of compound restrictors to the linear guideway systems subjected to tilt moments in both pitch and roll directions, and investigates, theoretically and experimentally, the static tilt characteristics of these aerostatic thrust bearings.  相似文献   
968.
BACKGROUND: The death rate for fatal fire accidents in Denmark has doubled since 1951, mostly due to an increase in the number of fire accidents associated with smoking. The most common cause of residential fire deaths in Denmark today is smoking, often combined with alcohol intoxication or handicap. METHODS: This was a case-control study of fatal fire accidents in private homes in the municipality of Copenhagen from 1991 to 1996. The fatal fire accidents were identified from a police register, and the two non-fatal fire accidents registered immediately before and after each fatal fire were selected as a control group. Information about the circumstances surrounding the fires was derived from the police reports. Multivariate logistic regression analysis was used to estimate the risk associated with each variable after adjusting for confounders. The analysis was performed on the basis of the theoretical model in which the variables were part of a causal network. RESULTS: The following five variables seemed to be of most importance: (1) localization of the victim close to the source of ignition (OR = 11), (2) physical handicaps (OR = 5), (3) chronic alcoholism (OR = 7), (4) clothing fires (OR = 24), and (5) alarm being given by a person not present at the scene of fire (OR = 33). Preventive measures are discussed in the light of the results.  相似文献   
969.
The molecular epidemiology of Pseudomonas aeruginosa infection in cystic fibrosis (CF) siblings was analysed by DNA fingerprinting using arbitrary primed polymerase chain reaction. A total of 306 strains collected from six pairs of siblings over a period of 20-126 months (median 64) was studied. Fifty-four different P. aeruginosa genotypes were recognized. Two out of six pairs of siblings were ultimately colonized by identical strains, and it was shown that a single P. aeruginosa clone can persist in an individual patient for over ten years. No overlap in P. aeruginosa genotypes was encountered between families, whereas in all families at least transient cross-colonization with the same genotype was observed. This finding demonstrates that P. aeruginosa cross-infection or acquisition of the same strain from an identical environmental source exists within the family situation, but does not always result in a long-term colonization by identical genotypes in all family members suffering from CF.  相似文献   
970.
This paper describes characteristics evaluation of the power conditioner which has the function of Maximum Power Point Tracking (MPPT) by “mountain climbing method” through computer simulations. The generated power on the constant voltage control is compared to the one on MPPT with the load matching correction factor (Kpm). In this simulation, the following parameters are chosen, the rate of the voltage ΔV on changing the operating point and of the voltage ΔVc on checking the maximum point.As a result, the influence of these parameters on Kpm is showed and it is made clear that we should decide the MPPT parameters with care.  相似文献   
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