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151.
Although in Japan the number of casualties from road traffic accidents decreased substantially during a period of improvement of safety measures, in recent years it has remained rather constant. To decrease accidents still further it is necessary to investigate the circumstances of road traffic accidents and the severity of resulting casualties in detail. For this purpose 167,721 cases of road traffic accident casualties occurring between February and April 1979, throughout Japan were analyzed. (1) It was found that 74.2% of all the cases suffered injuries corresponding to AIS-1; 30% of these involved neck injuries. (2) There were 2,654 fatal cases, 67% of which involved head injuries, chiefly cerebral contusion, cranial base fracture, and intracranial hemorrhage. There were fatal cases in the categories of AIS-3 or below which are generally considered not fatal, but those were due to complications. (3) The chief sites of injury varied according to the victim's mode of transport: in an automobile the neck was the site most frequently injured; on a motorcycle the legs and head were usually involved; on a bicycle or walking the head and legs were most at risk. (4) Injuries to pedestrians often fell under the severer AIS-4 or higher codes and constituted 43% of total deaths. (5) Accidents with automobiles changing lanes tended to cause serious injuries and many deaths. Other characteristics of road traffic accidents in Japan are analyzed and discussed.  相似文献   
152.
The decomposition process of supersaturated solid solution of the Pb-Sb alloys with a small amount of As (∼0.01 wt pct), has been investigated by electrical resistivity measurement. The precipitation process of the Pb-Sb alloys with As is similar to that of the previously reported Pb-As alloys. In the first stage, diffusion of quenched-in excess vacancies accelerates and rate-controls the migration of As and Sb atoms forming an intermediate phase. The second stage is the precipitation of the intermediate phase under the equilibrium vacancy concentration and the third is precipitation of the equilibrium phase. A retardation of reaction in isothermal aging and a partial reversion in isochronal aging appear between the last two stages. The analysis of resistivity change in the Pb-As and Pb-Sb-As alloys shows that the composition and the crystal structure of the intermediate phase are different from those of the equilibrium phase. The mechanism that the preexisted intermediate phase acts as a preferential nucleation site for the equilibrium phase can explain the enhanced precipitation phenomena of the Pb-Sb alloys with trace element As. The reason for the difference in behavior between As and Sb atoms in lead is also discussed.  相似文献   
153.
154.
Tuberculosis incidence and mortality rates are rising steeply, reflecting economic hardship and the deterioration of the health infrastructure. The human and technical resources needed to reverse this trend are on hand, but cannot be used effectively without an adequate financial input. The cost of controlling tuberculosis now is modest compared with the cost of allowing it to increase.  相似文献   
155.
HMB-45 is a monoclonal antibody specific for melanoma cells and premature developing melanocytes. We examined the expression and specific subcellular binding sites of HMB-45 in various types of melanocytes including epidermal melanocytes from fetuses and infants with or without tyrosinase-negative oculocutaneous albinism (type IA), melanin-producing and non-producing melanoma cell lines (G361 and MeWo), and in vivo melanoma cells (melanotic and amelanotic malignant melanoma). Subcellular HMB-45 binding was examined by using post-embedding immunogold electron microscopy with rapid freezing and freeze substitution fixation methods without the use of chemical fixatives to preserve the intracytoplasmic delicate antigen property of HMB-45. HMB-45 antigen was detected not only in in vivo melanoma cells and normal fetal melanocytes, but also in melanocytes in the other conditions. Post-embedding immunogold electron microscopy revealed that HMB-45 antigen was exclusively localized to stages I and II melanosomes in the cytoplasm of neoplastic melanocytes, but was detected mainly on stages II and III melanosomes in the melanocytes from fetuses and infants. In tyrosinase-negative oculocutaneous albinism, only stages I and II melanosomes were detected in the cytoplasm, but both stages of melanosomes were HMB-45 positive. We conclude that HMB-45 appears mainly on the immature melanosomes during melanogenesis in both neoplastic and non-neoplastic melanocytes regardless of their tyrosinase activity, but the intracytoplasmic localization of HMB-45 antigen is different by each condition of melanocytes.  相似文献   
156.
OBJECTIVE: Two-dimensional time-of-flight MR angiography was done with a 1.0 T whole-body imaging system. METHODS: The 10 mm thick presaturation slab was positioned between two sagittal imaging slices of the liver. Images were obtained through the right lobe of the liver by moving the slab and slices together. Each image was acquired during a breath-holding interval of 16 s. RESULTS: Since the directions of the portal and hepatic venous flows are opposite to each other in the right lobe, these two venous systems could be visualized on separate images by the interleaved presaturation slab. On the reconstructed angiograms, separation between the two venous systems was complete and even the fourth and fifth branches were demonstrated clearly. These images facilitate clear understanding of the structure of the intrahepatic blood vessels. CONCLUSION: Although this technique is limited to volunteer studies and works only on the right lobe of the liver, it will provide valuable information for evaluating the location and vascular involvement in various liver diseases.  相似文献   
157.
In order to improve the oral bioavailability (BA) of 2-butyl-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimid azole - 7-carboxylic acid (3: CV-11194) and 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4- yl]methyl]-1H-benzimidazole-7-carboxylic acid (4: CV-11974), novel angiotensin II (AII) receptor antagonists, chemical modification to yield prodrugs has been examined. After selective tritylation of the tetrazole rings in 3 and 4, treatment of N-tritylated benzimidazole-7-carboxylic acids (6, 7) with a variety of alkyl halides, followed by deprotection with hydrochloric acid, afforded esters of 3 and 4. Mainly 1-(acyloxy)alkyl esters and 1-[(alkoxycarbonyl)oxy]alkyl esters, double ester derivatives, were synthesized. Their inhibitory effect on AII-induced pressor response in rats and oral BA were investigated. (Pivaloyloxy)methyl and (+/-)-1-[[(cyclohexyloxy)-carbonyl]oxy]ethyl esters of 3 and 4 showed marked increases in oral bioavailability which significantly potentiated the inhibitory effect of the parent compounds on AII-induced pressor response. Among them, (+/-)-1-[[(cyclohexyloxy)carbonyl]oxy]ethyl 2- ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimida zole- 7-carboxylate (10s, TCV-116) was selected as a candidate for clinical evaluation.  相似文献   
158.
One hundred and eighty eight children with acute lymphoblastic leukemia (ALL) were treated in a Children's Cancer and Leukemia Study Group high-risk ALL 874 study from April, 1987 to September, 1991. These patients received a four-drug induction regimen followed by the early consolidation regimen, cranial irradiation at 6 months of remission and three years of continuation therapy with rotational administration of four drugs. The patients were randomized into two regimens. In regimen A, the consolidation chemotherapy consisted of the intermediate dose cytosine arabinoside (Ara-C), cyclophosphamide (CPM) plus 6MP, and in regimen B, it consisted of high-dose Ara-C plus CPM. Regimen A was given to 106 patients and 82 patients received regimen B. The complete remission induction rate for regimen A and B was 89.4% (93/104) and 98.7% (78/79), respectively. The 3-year event-free-survival (EFS) rate was 70.6% for regimen A, which was higher than the 56.7% for regimen B. The 3-year EFS rate was 44.4% for the 53 patients with an initial leukocyte count > or = 10 x 10(4)/microliters and 72.2% for 132 patients with a leukocyte count < 10 x 10(4)/microliter. We considered that Ara-C plus L-asp, added to the conventional high-risk ALL 811 protocol, improved the prognosis of the high risk ALL patients. However, further intensive chemotherapy was required for improvement of the outcome of the patients with hyperleukocytosis (> or = 10 x 10(4)/microliters).  相似文献   
159.
The non-homogeneous Sn-3.0Ag-0.5Cu (SAC305) lead-free solder alloy consists of Sn-rich (β-Sn) and eutectic phases. The mechanical properties of these individual phases were demonstrated to be a function of the temperature. The nanoindentation methodology was utilized to examine the mechanical properties at 60 °C, 80 °C, 110 °C, 130 °C, and 150 °C, respectively. It was found that for both Sn-rich phase and eutectic phase, the hardness and Young’s modulus exhibited the dependence on the temperature. Moreover, the creep deformation which occurred at the dwell time of sustained loading was quite sensitive to the prescribed temperature. Basically, the higher temperature resulted in a larger creep deformation. This in turn caused the variable strain rate sensitivity of the individual phases, which was extracted by Mayo-Nix approach. The Sn-rich phase showed larger creep deformation than that of eutectic phase. However, a greater strain rate sensitivity index value was obtained for eutectic phase at the temperature regime (25-130 °C). The derived activity energy implied that for both β-Sn and eutectic phases two rate-controlling processes took place during the creep deformation, in which the transition temperature is around 130 °C.  相似文献   
160.
Fe3O4–BaTiO3 composite particles were successfully prepared by ultrasonic spray pyrolysis. A mixture of iron(III) nitrate, barium acetate and titanium tetrachloride aqueous solution were atomized into the mist, and the mist was dried and pyrolyzed in N2 (90%) and H2 (10%) atmosphere. Fe3O4–BaTiO3 composite particle was obtained between 900° and 950°C while the coexistence of FeO was detected at 1000°C. Transmission electron microscope observation revealed that the composite particle is consisted of nanocrystalline having primary particle size of 35 nm. Lattice parameter of the Fe3O4–BaTiO3 nanocomposite particle was 0.8404 nm that is larger than that of pure Fe3O4. Coercivity of the nanocomposite particle (390 Oe) was much larger than that of pure Fe3O4 (140 Oe). These results suggest that slight diffusion of Ba into Fe3O4 occurred.  相似文献   
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