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991.
The effect of a novel synthetic trypsin inhibitor, 4-(2-succinimidoethylthio)-phenyl 4-guanidinobenzoate methanesulfonate (E3123), on severe acute pancreatitis was studied in trypsin-taurocholate-induced acute experimental pancreatitis in rats. Rats were divided into four groups according to difference of subdivided doses of E3123 with fixing the total dose at 3 mg/kg body weight. Group A: 1.5 mg/kg of E3123 subcutaneously (SC) each at 1 h before and after induction of pancreatitis. Group B: 1 mg/kg SC each at 1 h before, 1 and 3 h after induction. Group C: 1.5 mg/kg SC each at 1 and 3 h after induction. Group D: 1.5 mg/kg SC each at 3 and 5 h after induction of pancreatitis. The survival rate at 24 h was significantly improved in group B (77% in group B, vs. 36% in paired control; p < 0.01) and in group C (70 vs. 38%; p < 0.05), but not in group A or D. Residual tryptic activity of serum alpha 2-macroglobulin trypsin complex (alpha 2M-TRY) was reduced after the injection of E3123 though immunoreactive trypsin remained unchanged in the early phase of pancreatitis. The reduction of alpha 2M-TRY reflected the inhibitory capacity of E3123 in plasma. E3123 showed favorable effects on the initial stage of severe acute pancreatitis and the effects were probably based on the inhibition of alpha 2M-TRY activity in serum.  相似文献   
992.
The clinical significance of the presence or absence of regional variations in histologic differentiation within a primary colorectal carcinoma was investigated in this study. Regional variations in histologic differentiation were judged to be present when the low power field of a microscope was occupied by cancer tissue cytologically and architecturally different from that of the surrounding area. Regional variations in histologic differentiation were noted in 153 (42%) of 368 primary carcinomas. Carcinomas with regional variations were of an anaplastic histologic type and had a higher incidence of lymph node metastasis and a worse prognosis than those without regional variations. Thus, the histologic diversity within a carcinoma is thought to be important for determining the prognosis of patients with colorectal cancer.  相似文献   
993.
Periodontal ligament (PDL) cells are known to produce prostaglandin E2 (PGE2) in response to mechanical stress. However, the rate of PGE2 production from PDL cells in response to different magnitudes of tension forces has not been examined. This study, therefore, was undertaken to determine the effect of different magnitudes of tension forces on PGE2 production and inositol trisphosphate (IP3) levels in PDL cells in vitro. Human PDL cells were cultured on flexible-bottomed plates and placed on a Flexercell strain unit. Cells were flexed at six cycles (5-s strain, 5-s relaxation) at six steps of tension force (9, 12, 15, 18, 21, 24% increase in surface area) for 5 days. PGE2 production and IP3 levels were determined by radioimmunoassay. There was a 6- and 25-fold increase in the rate of PGE2 production by cells exposed to low (9%) and high (24%) tension forces, respectively, and these increases were tension force-dependent. Tension force also induced increases in the intracellular levels of IP3 that did not seem to be directly related to the production of PGE2. The different rates of PGE2 production by PDL cells in response to different magnitudes of mechanical stress may be of importance in PDL and alveolar bone metabolism.  相似文献   
994.
Although the letter of recommendation is the most commonly requested information relating to the personal qualities of applicants to dietetics internship programs, little research has focused on its value in selection decisions. The purpose of this study was to review how 318 letters of recommendation submitted on a standardized form related to the source of the reference and to the admission status of the applicants. The form contained 40 attributes that raters assigned to one of six categories. Nine of the 40 attributes were not rated by more than 75% of the raters, and 3 of the attributes were rated as outstanding by more than 60% of the raters. We concluded that these attributes did little to distinguish among applicants. The attribute maturity correlated 0.70 with 5 attributes and 0.99 with 2 attributes, so duplication of information existed. Raters were categorized as follows: adviser, major professor, other professor, employer, and other. The highest mean ratings were given by advisers; major professors rated students lowest. Analysis of variance supported a significant difference in rating by type of rater. Our findings suggest that fewer items should be used on a standardized form and that the type of rater should be specified if references are to distinguish among applicants.  相似文献   
995.
Influence of heart rate and respiration on beat-to-beat variability of left ventricular indexes measured by acoustic quantification was examined. These indexes were correlated with their counterparts measured by M-mode echocardiography. Parameters of left ventricular performance were recorded for 1 full minute in 43 children with a mean age of 5.9 +/- 3.9 years. Beat-to-beat variability was documented. The effect of respiration on such variability was examined in another 10 subjects. A wide range of heart rates and respiration did not show significant influence on the degree of variance among these parameters. The indexes measured correlated well with their counterparts measured by M-mode echocardiography. Acoustic quantification separated those with normal from those with abnormal left ventricular function with the same statistical significance as did M-mode echocardiography. A moderate degree of beat-to-beat variability occurs in acoustic quantification-derived left ventricular indexes. Heart rate variability and respiration do not influence the beat-to-beat variance of parameters of left ventricular performance measured with the acoustic quantification. Excellent correlation was documented between this technique and M-mode echocardiography.  相似文献   
996.
An optical device with various functions is actualized by integrating vertically and directly heterojunction phototransistors and a laser diode and by adjusting the internal optical feedback. The optical amplification with a good linearity between input and output lights is realized by suppressing the internal optical feedback. The large gain of over 100 is achieved in the wide wavelength range from 0.75 to 1.25 μm. The optical thresholding function is achieved by changing the load line in the case of the optical amplification. The optical switching function with large gain and high sensitivity is obtained by utilizing the internal optical feedback most effectively. The optical bistable function is obtained when the amount of the optical feedback becomes moderate. The optical feedback inside the device is theoretically investigated to explain these functions systematically  相似文献   
997.
With concern increasing over environmental issues, reduction in automobile weight has become more important and has been proved to be effective for improving fuel efficiency. Metal Matrix Composites (MMC) are expected to be useful to cope with these problems. The authors have developed a new aluminium engine block which has the cylinder bore surface structure reinforced with short hybrid fibres of alumina and carbon.  相似文献   
998.
Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
999.
Human arm motions were simulated using both computer graphics and an industrial robot under various velocity patterns, and evaluated to examine which factors are essential for human-likeness. The results are summarized as follows. First, the velocity peak position in the normalized movement time of the motion is important for the emotion of human-likeness. Second, the maximum value of the velocity affects the human impression of the motion. There exists an appropriate maximum value which best gives a subject the impression of human-likeness. Finally, the emotion of human-likeness is related to that of agreeableness. These results are almost the same for both a simulated motion on CRT and a robot motion.

Relevance to industry

In the future, robots will play important roles by assisting or cooperating with humans in various industrial fields. In such cases, a robot's motion must be well designed taking into account human perception. The results of the research will become an important guide for the design of a robot's motion.  相似文献   

1000.
The simultaneous spectral equalisation of the C- and L-bands, achieved using a planar lightwave circuit (PLC)-based dynamic gain equaliser consisting of 10 cascaded Fourier-series Mach-Zehnder interferometers, is described. Gain flattening over 68 nm with a 0.9 dB ripple for an Er3+-doped tellurite fibre amplifier was realised  相似文献   
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