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OBJECTIVE: The prevalence of obesity and thinness is unknown among Iranian high-school age girls. We determined the prevalence of overweight and underweight among Iranian high-school girls from Kerman (south-east province of Iran). DESIGN: A cross-sectional study of indicative cluster sample. MEASUREMENTS: Weight, height, body mass index (BMI), chest, waist, abdomen, hip and thigh circumference of 1000 Iranian high-school girls aged 14-21 y (mean (standard deviation, s.d.) 16.2 (1.3)) were measured. The criteria for very underweight, underweight, desirable weight, grade 1, 2 and 3 overweight used in the present study were: BMI in kg/m2 < 15, 15-19.9, 20-24.9, 25-29.9, 30-39.9 and > or = 40, respectively. RESULTS: 4.6% (95% confidence interval (CI): 3.4%-6.1%) were grade 1 overweight (BMI = 25.0-29.9), 0.7% (95% CI: 0.3%-1.4%) were grade 2 overweight (BMI = 30-39.9), and none were grade 3 overweight (BMI > or = 40), while 54.6% (95% CI: 51.5%-57.7%) were underweight (BMI = 15-19.9) and 1.6% (95% CI: 0.9%-2.6%) were very underweight (BMI < 15). The mean (s.d.) BMI was 19.8 (2.9) (95% CI: 19.6-20.0). The mean (s.d.) waist-to-hip ratio (WHR), abdomen-to-hip ratio and chest-to-hip ratio values were 0.8 (0.06) (95% CI: 0.8-0.81), 0.8 (0.07) (95% CI: 0.8-0.81) and 0.9 (0.07) (95% CI: 0.9-0.91), respectively, in this sample. CONCLUSION: The results suggest a low prevalence of overweight among Iranian young women.  相似文献   
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1.55 ?m-band distributed-feedback laser diodes with double-channel planar buried heterostructure (DFB-DC-PBH LDs) have been developed. As well as low threshold current, 19 mA at room temperature, stable CW single-longitudinal-mode operation up to the high power level of 23 mW and the high temperature of 108°C has been obtained.  相似文献   
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To elucidate the role of neutrophils in the tissue damage of crescentic glomerulonephritis (GN), we examined neutrophils infiltrated in renal tissues and the localization of neutrophil elastase (NE), as a neutrophil-derived tissue destructive mediator, using an immunohistochemical technique with antibodies specific for neutrophils and neutrophil elastase; the enzyme histochemical technique (chloroesterase staining) also was used to detect neutrophils. In normal controls, neutrophil infiltration was scarce, and NE was localized in neutrophil cytoplasm. Neutrophils were abundant in crescentic GN and infiltrated in the glomerulus and interstitium; the infiltrating neutrophils were often aggregated. NE was localized in the cytoplasm of neutrophils and also appeared extracellularly (in granular or diffuse patterns) in glomerular necrotizing lesions, crescents, ruptured portions of Bowman's capsules, and in periglomerular and perivascular sites of the interstitium. Moreover, urinary concentration of NE measured by enzyme-linked immunosorbent assay (ELISA) in crescentic GN patients was significantly higher than in normals (93.6 +/- 13.3 v 1.4 +/- 0.5 microg/g x Cr, respectively; P < .001). These data suggest that NE plays a significant role in renal tissue damage, especially in the formation of glomerular necrotizing and crescentic lesions and in periglomerular interstitial lesions of crescentic GN.  相似文献   
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The authors have proposed an architecture for a compact image-capturing system called TOMBO (thin observation module by bound optics), which uses compound-eye imaging for a compact hardware configuration [Appl. Opt. 40, 1806 (2001)]. The captured compound image is decomposed into a set of unit images, then the pixels in the unit images are processed with digital processing to retrieve the target image. A new method for high-resolution image reconstruction, called a pixel rearrange method, is proposed. The relation between the target object and the captured signals is estimated and utilized to rearrange the original pixel information. Experimental results show the effectiveness of the proposed method. In the experimental TOMBO system, the resolution obtained is four times higher than that of the unit image that did not undergo reconstruction processing.  相似文献   
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High-power aging tests on 1.3 ?m double-channel planar buried-heterostructure (DC-PBH) lasers with a reflective coated mirror have been performed. Stable operation for over 6000 h has been demonstrated under constant power conditions of 20 and 30 mW from the front facet at 50°C.  相似文献   
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Sato N  Yamaguchi Y 《Neural computation》2003,15(10):2379-2397
Recent experimental evidence on spike-timing-dependent plasticity and on phase precession (i.e., the theta rhythm dependent firing of rat hippocampal cells) associates the contribution of phase precession to episodic memory. This article aims at clarifying the role of phase precession in memory storage. Computer simulations show that the memory storage in the behavioral timescale varies in timescale of the temporal sequence from half a second to several seconds. In contrast, the memory storage caused by traditional rate coding is restricted to the temporal sequence within 40 ms. During phase precession, memory storage of a single trial experience is possible, even in the presence of noise. It is therefore concluded that encoding by phase precession is appropriate for memory storage of the temporal sequence in the behavioral timescale.  相似文献   
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