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161.
To understand the characteristic clinical features of human immunodeficiency virus (HIV)-related oral lesions and determine the prevalence of various oral lesions in HIV-infected patients in Taiwan, we conducted a cross-sectional study of 207 HIV-infected patients at the Taipei Municipal Institute for Venereal Disease Control. Overall, 108 (52.2%) patients had at least one oral lesion. The most common oral manifestation of HIV infection among these 207 patients was oral hairy leukoplakia (OHL, 29.5%), followed by candidiasis (12.1%), xerostomia (10.6%), aphthous ulcers (8.7%), and linear gingival erythema (5.8%). Less frequently encountered oral lesions included leukoplakia (1.9%), papilloma (1.4%), necrotizing ulcerative periodontitis (1.0%), Kaposi's sarcoma (1.0%), herpes simplex (0.5%), Burkitt's lymphoma (0.5%), and parotid gland enlargement (0.5%). Thirty-one (15%) patients had multiple oral lesions. Patients with oral candidiasis or multiple oral lesions had significantly lower mean CD4 lymphocyte counts and CD4/CD8 lymphocyte ratios than those without any oral lesions (p < 0.05). Chi-square analysis revealed that patients with CD4 lymphocyte counts below 200 cells/mm3 were more prone to have OHL (p < 0.002), oral candidiasis (p < 0.001) and multiple oral lesions (p < 0.001). Those with CD4/CD8 lymphocyte ratios below 0.4 were more likely to have OHL (p < 0.02), oral candidiasis (p < 0.01) and multiple oral lesions (p < 0.02) than those with higher counts. In conclusion, the occurrence of oral lesions, especially OHL and oral candidiasis, is fairly common in Taiwanese HIV-infected patients. 相似文献
162.
Shau-Gang Mao Yu-Zhi Chueh 《Microwave and Wireless Components Letters, IEEE》2007,17(3):181-183
This work presents a novel coplanar waveguide (CPW) bandpass filter (BPF) that uses electromagnetic bandgap (EBG) resonators to reduce the size and suppress the harmonic responses. The propagation characteristic of the EBG structure is investigated by its associated equivalent circuit model. Compared with the conventional half-wavelength resonator at 5GHz, the EBG resonator is 60.5 % more compact. Based on the EBG CPW resonators, the inductively-coupled two-pole BPF with 3.8% 3-dB bandwidth and 2-dB insertion loss at 5GHz is implemented. This structure generates a 59.6% reduction in size and suppresses a second harmonic passband when compared with a conventional filter. To eliminate the third harmonic response, the proposed EBG CPW BPF further incorporates two EBG structures into its input and output ports and has the merit of a small circuit area 相似文献
163.
A novel dual-passband filter using the unit-cell (UC) composite right/left-handed (CRLH) coplanar waveguide (CPW) open-circuited stub and the UC electromagnetic bandgap (EBG) CPW short- circuited stub is proposed. The CRLH open-circuited and EBG short-circuited stubs in parallel connection are equivalent to the dual-passband lumped-element CPW resonators within the specific frequency range. The performance of a third-order dual-passband filter with Chebyshev responses is measured and validated by full-wave simulation. 相似文献
164.
TaSi2 nanowires have been synthesized on Si substrate by annealing FeSi2 thin film and NiSi2 films at 950 °C in an ambient containing Ta vapor whose length would be grown up to 13 μm. The metallic TaSi2 nanowires exhibit excellent electrical properties with remarkable high failure current density of 3 × 108 A cm− 2. In addition, the growth mechanism is addressed in detail, The TaSi2 nanowires are formed in three steps: segregation of Si atoms from the FeSi2 thin film and NiSi2 films underlayer to form Si base, growth of TaSi2 nanodots on Si base, and elongation of TaSi2 nanowire along the growth direction. This simple approach promises future applications in nanoelectronics and nano-optoelectronics. 相似文献
165.
166.
Hierarchical tree-shaped nanostructures, nanobelts, and nanowires of Zn3P2 were synthesized in a thermal assisted laser ablation process. All nanostructures are tetragonal phased Zn3P2 with excellent crystallinity and are free from an oxidization layer according to electron microscopy and X-ray diffraction analyses. Optical measurement revealed a strong absorption from the ultraviolet to near-infrared regions. Optoelectronic devices fabricated using individual nanowires demonstrate a high sensitivity and rapid response to impinging light. A crossed heterojunction of an n-type ZnO nanowire and a p-type Zn3P2 nanowire has been characterized, and it offers a great potential for a high efficient spatial resolved photon detector. 相似文献
167.
168.
Jingyu Zou Hin‐Lap Yip Yong Zhang Yan Gao Shang‐Chieh Chien Kevin O'Malley Chu‐Chen Chueh Hongzheng Chen Alex K.‐Y. Jen 《Advanced functional materials》2012,22(13):2804-2811
Although high power conversion efficiencies (PCE) have already been demonstrated in conventional structure polymer solar cells (PSCs), the development of high performance inverted structure polymer solar cells is still lagging behind despite their demonstrated superior stability and feasibility for roll‐to‐roll processing. To address this challenge, a detailed study of solution‐processed, inverted‐structure PSCs based on the blends of a low bandgap polymer, poly(indacenodithiophene‐co‐phananthrene‐quinoxaline) (PIDT‐PhanQ) and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) as the bulk heterojunction (BHJ) layer is carried out. Comprehensive characterization and optical modeling of the resulting devices is performed to understand the effect of device geometry on photovoltaic performance. Excellent device performance can be achieved by optimizing the optical field distribution and spatial profiles of excitons generation within the active layer in different device configurations. In the inverted structure, because the peak of the excitons generation is located farther away from the electron‐collecting electrode, a higher blending ratio of fullerene is required to provide higher electron mobility in the BHJ for achieving good device performance. 相似文献
169.
Wang SM Shih TS Huang YS Chueh MR Chou JS Chang HY 《Journal of hazardous materials》2006,138(3):518-525
The objectives of this study were to evaluate the protective effectiveness of various personal protective equipment and the respective exposure contributions from respiratory and skin exposures of N,N-dimethylformamide (DMF) with a self-comparison study design. Two high-, four intermediate- and four low-DMF exposure workers from a synthetic leather factory were monitored in airborne DMF concentrations and N-methylformamide (NMF) concentrations in urine across four consecutive days. The workers were designated to wear no personal protective equipment on the first day. The barrier cream, rubber gloves and rubber gloves plus respirator were used on the second, third and fourth days, respectively. Person-to-personal observation was performed in the field to record all high and low exposure tasks during work for each subject. Protective effectiveness index (PEI) was used to evaluate different glove effectiveness. We concluded that the direct skin contact to the strong skin penetrates like DMF could be a more significant exposure source than the respiratory exposure in the actual occupational environment. The provision of protective equipment from skin exposure could be more important than that from respiratory exposure. The application of barrier cream could be as effective as wearing impermeable rubber gloves in the prevention from the skin penetrate in the occupational settings. 相似文献
170.
Kuang-Shun Chueh Kuan-Hua Huang Jian-He Lu Tai-Jui Juan Shu-Mien Chuang Rong-Jyh Lin Yi-Chen Lee Cheng-Yu Long Mei-Chen Shen Ting-Wei Sun Yung-Shun Juan 《International journal of molecular sciences》2022,23(10)
The present study attempted to elucidate whether intravesical instillation of platelet-rich plasma (PRP) could decrease bladder inflammation and ameliorate bladder hyperactivity in ketamine ulcerative cystitis (KIC) rat model. Female Sprague Dawley (S-D) rats were randomly divided into control group, ketamine-treated group, ketamine with PRP treated group, and ketamine with platelet-poor plasma (PPP) treated group. Cystometry and micturition frequency/volume studies were performed to investigate bladder function. The morphological change of bladder was investigated by Mason’s trichrome staining. Western blotting analysis were carried out to examine the protein expressions of inflammation, urothelial differentiation, proliferation, urothelial barrier function, angiogenesis and neurogenesis related proteins. The results revealed that treatment with ketamine significantly deteriorated bladder capacity, decreased voiding function and enhanced bladder overactivity. These pathological damage and interstitial fibrosis may via NF-κB/COX-2 signaling pathways and muscarinic receptor overexpression. PRP treatment decreased inflammatory fibrotic biosynthesis, attenuated oxidative stress, promoted urothelial cell regeneration, and enhanced angiogenesis and neurogenesis, thereafter recovered bladder dysfunction and ameliorate the bladder hyperactivity in KIC rat model. These findings suggested that the PRP therapy may offer new treatment options for those clinical KIC patients. 相似文献