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1.
A high resolution depth attenuation product (Kdhires) was developed using MODIS 500 m and 250 m spectral bands. The Kdhires was compared with Wang’s operational Kd for the Chesapeake Bay. Minimal differences were observed between the two methods, with greatest deviation occurring in areas of high turbidity in the tributaries. After tuning the new Kdhires, the mean absolute error and bias between the two algorithms was 0.22 m?1 and 0.026 m?1, indicating good agreement. Higher spatial resolution provides for improved retrievals along the coast and into the narrow sections of the tributaries, coinciding with areas of concern to estuarine health and coastal management applications.  相似文献   
2.
OBJECTIVE: The aim of this study was to evaluate the relationship between the degree of conversion (DC) of composites and the light intensity using LED-curing units and also to determine the amount of exposure required to achieve optimal curing. METHOD: The light outputs of light-curing units and the depths of cure of composites exposed to these units were determined using the methods outlined in modified ISO standards, ISO/TS10650 and ISO 4049, respectively. The distributions of DC in composites were investigated by IR spectra of microareas obtained at various depths from the irradiated surface of thin specimens cut out from the cured composites. IR spectra were measured using a Fourier transform infrared spectrometer equipped with a microscopic unit. DC was calculated from the changes in the amount of C=C double bonds in the IR spectra. RESULTS: The light intensity at various depths through the cured composite was calculated from the attenuation coefficient of each material, obtained from the linear relationship between the depth of cure and the logarithm of the amount of exposure, which is defined as the product of the irradiance and irradiation time. There was a third or fourth order regression relationship between DC and the logarithm of total light energy at a particular depth. SIGNIFICANCE: The minimum light energy required to produce a saturated DC was about 1000 s mW/cm2.  相似文献   
3.
目的 探讨经尿道前列腺汽化电切术(transurethral electrovaporization of the prostate,TUVP)电切深度标识的可行性。方法 回顾性分析616例前列腺增生症临床资料,其中310例术前彩超提示合并前列腺钙化,156例合并膀胱结石,23例合并膀胱肿瘤。TUVP操作过程中,观察到合并前列腺结石和机械操作“打滑现象”,停止电切。结果 全组手术时间30~120min,平均75min。术中验证术前彩超提示合并前列腺钙化的310例前列腺钙化为结石,同时发现其余306例均存在结石。1例术中膀胱穿孔,无尿道直肠瘘和尿道电切综合征发生。325例随访3~6个月,平均4.5月,最大尿流率由6.5~8.5ml/s提高到18~22ml/s,残余尿由70~150ml降至0~10ml,国际前列腺症状评分由19~24.5分降至0~7分。138例膀胱结石和23例膀胱肿瘤无复发。结论 前列腺结石和机械操作“打滑现象”作为TUVP的电切深度标识是切实可行的。  相似文献   
4.
The initiation site of seizure discharges and the relationship between behavioral manifestations and electroencephalography were investigated in the El mouse, a hereditary epilepsy model. The chronic depth electrodes were implanted stereotaxically into the frontal cortex, parietal cortex, temporal cortex, hippocampus, striatum, amygdaloid complex, non-specific nuclei of thalamus and substantia nigra. Electrical activities were recorded in freely moving condition with use of the buffer amplifier devised in the laboratory and behaviors were monitored simultaneously. Seizure spike discharges started in the parietal cortex and spread out into other brain areas. When the hippocampus was involved, the tonic convulsion occurred behaviorally. The paper describes the first direct evidence of the initiation and propagation of seizure discharges in the brain of El mouse.  相似文献   
5.
Thirty-five subjects from two independent studies were awakened at EEG-defined periods during the night with 1000 Hz ascending tone series. Awakenings were made five to eight times per night during stage 2, stage 4, or REM sleep over a series of nights in good and poor sleepers. Reliability was assessed within stage, within night, between stages, and between nights. Good and poor sleepers did not differ in either depth of sleep or reliability of arousal threshold and were thus pooled in the analyses. From night to night, the most consistency was seen in stage 4 (r=.74), although REM reliability (r?1= .49) and stage 2 reliability (r?1= .50 and r?1= .69 in the two respective studies) estimates were also greater than zero. Early sleep onset and morning arousals were more variable. Reliability estimates on arousal thresholds taken within the same night for stage 2 were r= .64 and r?1= .77 for the two studies and r= .96 for REM. The depth of sleep was not correlated with awake auditory threshold. It was concluded that five or six carefully placed arousals could give a good estimate of an individual's usual arousal threshold.  相似文献   
6.
Photoacoustic Fourier transform infrared (PA-FT-IR) depth profiling spectra of the enamel of an intact human tooth are obtained in a completely nondestructive fashion. The compositional and structural changes in the tissue are probed from the enamel surface to a depth of about 200 m. These changes reflect the state of tissue development. The subsurface carbonate gradient in the enamel could be observed over the range of about 10–100 m. The carbonate-to-phosphate ratio increases in the depth profile. The depth profile also reveals changes in the substitutional distribution of carbonate ions. Type A carbonates (hydroxyl substituted) increase relative to type B carbonates (phosphate substituted) with increasing thermal diffusion length. In addition to the changes in the carbonate ion distribution and content, the PA-FT-IR depth profile clearly indicates a dramatic increase in the protein content relative to the phosphate content with increased depth. The changes in the carbonate content and distribution, along with the changes in the protein content, may be responsible for the changes observed in the apatitic structure in the depth profile of the enamel.  相似文献   
7.
深刺局部穴治疗三叉神经痛疗效观察   总被引:8,自引:0,他引:8  
张晓阳 《中国针灸》2005,25(8):549-550
目的:寻找提高三叉神经痛疗效的有效方法.方法:将90例原发性三叉神经痛患者随机分为深刺组(45例)、常规针刺组(45例).常规针刺组以局部近取浅刺和循经远取手足阳明经穴位为主,深刺组在此基础上对局部穴位采用深刺达神经干的方法.治疗3个疗程后统计疗效.结果:两组均收到明显疗效,深刺组临床治愈12例,显效24例,好转7例,无效2例,有效率为95.6%;而常规针刺组分别为7例、15例、12例、11例、75.6%.深刺组疗效优于常规针刺组(P<0.05).结论:针刺治疗三叉神经痛,局部穴位深刺加循经远取手足阳明经穴位,能明显提高疗效.  相似文献   
8.
Epilepsy surgery uses both depth electrodes (DEs) and subdural electrodes (SE). DEs have mainly been developed and used in Europe. As we are able to use the DEs safely due to the current advanced level of technology, use of DEs has been increasing rapidly over the last decade. Unlike placement of SEs, which simply requires craniotomy, DE placement generally requires stereotactic techniques such as frame-based stereotactic or robotic arm-based methods. However, such methods are not always available at every epilepsy center. We therefore invented guide pipes for accurate DE placement. With this guide pipe and neuronavigation-based (NB) DE placement system, we are able to place DEs accurately. However, the disadvantages of our original procedure were a relatively large skin incision and the difficulty in anchoring DEs. The purpose of this technical note is to introduce a method to perform NB DE placement with a smaller skin incision and simple anchoring procedure. As we could make the skin incision smaller and achieved easier anchoring of DEs using a titanium plate, we hope this procedure will help facilities to perform DE placement with neuronavigation systems.  相似文献   
9.
10.
《Diabetes & metabolism》2020,46(3):230-235
AimMortality rates are decreasing in patients with diabetes. However, as this observation also concerns patients with diabetic foot ulcer (DFU), additional data are needed. For this reason, our study evaluated the 5-year mortality rate in patients with DFU during 2009–2010 and identified risk factors associated with mortality.MethodsConsecutive patients who attended a clinic for new DFU during 2009–2010 were followed until healing and at 1 year. Data on mortality were collected at year 5. Multivariate Cox proportional-hazards model was used to identify mortality risk factors.ResultsA total of 347 patients were included: mean age was 65 ± 12 years, diabetes duration was 16 [10; 27] years; 13% were on dialysis; and 7% had an organ transplant. At 5 years, 49 patients (14%) were considered lost to follow-up. Total mortality rate at 5 years was 35%, and 16% in patients with neuropathy. On multivariate analyses, mortality was positively associated with: age [hazard ratio (HR): 1.05 (1.03–1.07), P < 0.0001]; duration of diabetes [HR: 1.02 (1.001–1.03], P = 0.03]; PEDIS perfusion grade 2 vs. 1 [HR: 2.35 (1.28–4.29), P = 0.006)]; PEDIS perfusion grade 3 vs. 1 [HR: 3.14 (1.58–6.24), P = 0.001); and ulcer duration at year 1 [HR 2.09 (1.35–3.22), P = 0.0009].ConclusionMortality rates were not as high as expected despite the large number of comorbidities, suggesting that progress has been made in the health management of these patients. In particular, patients with neuropathic foot ulcer had a survival rate of 84% at 5 years.  相似文献   
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