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961.
The purpose of this study was to detect factors affecting lumbar bone mineral density (BMD) of general inhabitants in a rural community. A cohort consisting of 2261 inhabitants aged 40-79 years was set up based on the resident registration in Taiji town, Wakayama Prefecture in 1992. Fifty men and 50 women in each of four age strata (40-49, 50-59, 60-69, 70-79), totaling 400 inhabitants, were selected randomly. After completion of a questionnaire by an interviewer, items about physical characteristics such as height, body weight, wrist length and grip power were measured. Examination of BMD of the lumbar spine and proximal femur by dual energy X-ray absorptiometry was performed. Correlation coefficients between BMDs and values of physical characteristics were determined. Lumbar BMD was examined to determine whether the following factors were positive or negative: past history, alcohol consumption, smoking habit, dietary habit, exercise, and in addition, pregnancy times and menstrual status for women. Among the values of physical characteristics, body weight was the most closely correlated with lumbar BMD. The items that showed significantly high values as factors affecting lumbar BMD were a past history of diabetes mellitus (men and women in their 70s), and exercise (men in their 50s and women in their 40s). Regarding pregnancy times and menstruation, BMD in women with a history of childbirth was significantly higher than that in those without the history among the women in their 70s. Although the BMD in the women with lactation was significantly lower than that in those without it among the women in their 40s, there was no difference in BMD between the women with and without the history who were 50 years old or over. The effect of menstrual status was investigated according to years after menopause in the women in their 50s. BMD was significantly lower in the women with ar least six years after menopause than in those within five years.  相似文献   
962.
We report two patients with systemic lupus erythematosus (SLE) in whom cytomegalovirus (CMV) infection may have played a significant role in the exacerbation or onset of symptoms. The first patient had thrombocytopenia and the second had proteinuria. CMV infection was observed in both patients when their symptoms developed.  相似文献   
963.
964.
A bioelectronic sniffer device for trimethylamine (TMA) in the gas phase "fish-odor substance" was constructed using a flavin-containing monooxygenase 3 (FMO3, one of xeno-biotic metabolizing enzymes) and a reaction unit with both gas and liquid cells separated by a porous poly(tetrafluoroethylene) diaphragm membrane (pore size: 30-60 /spl mu/m, thickness: 0.20 mm). A substrate regeneration cycle was applied to the FMO3 immobilized device in order to amplify the output signal by coupling the monooxygenase with a reducing reagent system of ascorbic acid (ASA) in phosphate buffer. The sniffer device with 10.0 mmol/l AsA could be used to measure TMA vapor from 0.52 to 105 ppm; this covers the maximum permissible concentration in the work place (5.0 ppm of time weighted average concentration) and the sensing level-5 of smell in humans (3.0 ppm). Since the application of the substrate regeneration cycle was possibly successful, it improved the sensitivity of the FMO3 immobilized device. The sniffer device possessed high selectivity for TMA being attributable to the FMO3 substrate specificity, continuous measurability, and good reproducibility in the repeatedly measurements (coefficient of variation = 2.41%, n=10).  相似文献   
965.
A 4-Mb CMOS SRAM with 3.84 μm2 TFT load cells is fabricated using 0.25-μm CMOS technology and achieves an address access time of 6 ns at a supply voltage of 2.7 V. The use of a current sense amplifier that is insensitive to its offset voltage enables the fast access time. A boosted cell array architecture allows low voltage operation of fast SRAM's using TFT load cells  相似文献   
966.
Ti/Si/TiC powders with molar ratios of 1:1:2 (M1) and 2:2:3 (M2) were prepared for the synthesis of a ternary carbide Ti3SiC2 by using the mixture method for 24 hours in an Ar atmosphere. The synthesis process was conducted at 1200 °C to 1400 °C under a pressure of 50 MPa, using the pulse-discharge sintering (PDS) technique. After sintering, the phase constituents and microstructures of the samples were analyzed by X-ray diffraction (XRD) technique and observed by optical microscopy and scanning electron microscopy. The results showed that the phases in all the samples consisted of Ti3SiC2 and small amounts of TiC, and the optimum sintering temperature was found to be in the relatively low range of 1250 °C to 1300 °C. By the standard additive method, the relative content of Ti3SiC2 was calculated. For the M1 samples, the lowest TiC content can be only decreased to about 3 to 4 wt pct, whereas the content of Ti3SiC2 in the M2 samples is always lower than that in the M1 samples. When the M2 powder was sintered at 1300 °C for 8 to 240 minutes, the TiC peaks were found to show a very low intensity, and the corresponding content of Ti3SiC2 was calculated to be higher than 99 wt pct. The grain size of Ti3SiC2 increased from 5 to 10 μm to 80 to 100 μm in the entire applied sintering temperature range. The relative density of the M2 samples was measured to be higher than 99 pct at sintering temperatures above 1275 °C. It indicates that the PDS technique can rapidly synthesize high-content Ti3SiC2 from the Ti/Si/TiC powders in a relatively low temperature range.  相似文献   
967.
Eight cases of cervical necrotizing fasciitis are presented. Three were odontogenic, two were pharyngeal in origin and three were primary or idiopathic. Soft tissue gas was recognized in four patients. The bacteriology showed streptococci on the top of the list (50%), while for the idiopathic cases, it was monomicrobial and caused by staphylococci. Third generation cephalosporin and metronidazole represent good initial empirical antibacterial coverage. Histopathologically, all cases showed extensive necrosis of the debrided fascia and vascular thrombosis of the dermal vessels. The mortality rate was 3/8 (37.5%). Early diagnosis of cervical necrotizing fasciitis and initiation of definitive therapy in an intensive care environment is essential to minimize mortality. It is also important to recognize that this devastating infection may occur spontaneously, and it should be suspected in patients with unexplained soft tissue pain and tenderness.  相似文献   
968.
BACKGROUND: The Iceman is a prehistoric, completely preserved, 5300-year-old male human mummy. OBJECTIVE: To obtain the first biopsy specimens from inside the Iceman while meeting an extended standard of hygiene and following precise intraoperative guidance to the site of biopsy and keeping tissue damage to a minimum. DESIGN: Biopsy specimens from the nose, the maxillary sinus, and the larynx of the Iceman were obtained. Special caution had to be taken while performing the biopsies to not contaminate the Iceman with heavy metals or remnants of microorganisms. SUBJECT: The Iceman, a cadaver kept frozen in a glacier for 5300 years. The Iceman is in an excellent state of preservation and will allow fundamental histological, morphological, and molecular genetic insights into early man. INTERVENTION: The biopsies were planned and executed with the aid of Interventional Video Tomography, a system that guides the surgeon to the target area by combining live video with existing imaging modalities. The system does not need mechanical fixation of the subject (the Iceman) and is barely in physical contact with the subject; thus, it was the ideal tool for guiding the surgeon to the site of the biopsy samplings through a tiny canal into the nose, the maxillary sinus, and the larynx of the Iceman. RESULTS: We have obtained a number of tissue samples by precisely guided 3-dimensional navigation. Unnecessary tissue damage was avoided. CONCLUSIONS: Visual inspection of the extracted mucosa showed typical human cadaver tissue, despite its age, without clinical abnormalities. Currently, the samples are being investigated by various international scientific groups.  相似文献   
969.
2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA) and its desmethoxy derivative (DIBOA) are major allelochemicals produced by corn, wheat, rye and related monocotyledons. These benzoxazinone derivatives have a wide variety of biological actions, including antifungal and mutagenic activities. Structure-activity relationships of these compounds and their derivatives (benzoxazinoids), the reactivity of benzoxazinoids with nucleophiles, and the substituent effects of the 7-methoxy and 2-hydroxy groups are discussed in relation to the molecular mechanisms of the biological activities.  相似文献   
970.
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