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排序方式: 共有237条查询结果,搜索用时 15 毫秒
1.
目的探讨腮腺切除术中应用沿面神经总干顺行解剖面神经的治疗效果及安全性。方法选取我院2016年2月至2019年3月收治的60例择期行腮腺切除术的患者,随机分为观察组与对照组各30例。对照组沿面神经总干逆行解剖面神经,观察组沿面神经总干顺行解剖面神经,观察两组患者术后1个月面神经功能及术后并发症发生情况。结果术后1个月,两组患者的面神经功能分级比较无统计学差异(P>0.05);观察组的术后并发症发生率为10.00%,明显低于对照组的33.33%(P <0.05)。结论临床行腮腺切除术中,沿面神经总干顺行解剖面神经可降低术后并发症发生率,值得推广。  相似文献   
2.
观察硒和维生素A(VA)对支原体肺炎的治疗效果.方法 采用双盲随机对照2×2析因实验设计,选择100例住院支原体肺炎患儿,分为补硒组26例,补VA组23例,补硒和VA组30例以及病例对照组21例,正常组21例.一次补硒量为1mg亚硒酸钠和/或15万单位VA,对照病例组给予常规治疗.结果 与对照组比,治疗后3个补充组的症状和体征缓解天数均有不同程度缩短(P<0.05),补硒组白细胞硒和谷胱甘肽过氧化物酶水平显著上升(P<0.05),补VA、补硒组血清VA水平上升(P<0.01),细胞免疫功能有所改善.结论 硒和VA有协同作用,补充硒或同时加VA,作为辅助治疗支原体肺炎的方法,安全、有效.  相似文献   
3.
Dog pancreatic islets isolated by an enzymatic digestion method were encapsulated in an alginate-poly L-lysine-alginate membrane. These microencapsulated pancreatic islets were cultured in vitro to study their ability of insulin secretion. Portions of these in vitro-cultured microencapsulated pancreatic islets were taken out for a viability dye exclusion study as well as for pathologic studies to correlate them with insulin secretion ability. We found that there was a strong correlation between them. Good insulin-secreting microcapsules showed well-preserved cell membranes and beta-cell granules. An in vitro culture for one to two days in RPMI-1640 made the islets more stable, the cellular surface became smoother and the beta-granules were in better shape. The microencapsulated pancreatic islets were also injected into the peritoneum of streptozotocin-induced diabetic CDF1 mice. Blood glucose levels dropped and stayed low for up to 60 days. But, when non-encapsulated dog pancreatic islets were used, the blood glucose levels remained low for only about 14 days. A small portion of the injected microcapsules were washed out at specific times for pathologic study. Up to 28 days after injection, only a few of the injected microcapsules showed pericapsular cellular infiltrate. However, after 56 days, most of the microcapsules showed dense pericapsular cellular infiltrate. Immunohistochemical analysis of these infiltrates showed that the majority of cells were fibroblasts and macrophages. Most of the cells located in the inner portion of the infiltrate were fibroblasts, while the macrophages were located mainly on the outer portion. Both scanning and transmission electron microscopy showed that the surface of the microcapsule outer wall was much smoother than the inner wall. The size of the microcapsules was approximately 0.6-0.8 mm and the thickness of the wall measured around 10 nm. The smaller the microcapsule is, the less chance there is of rupture with release of the xenographic islets. Once the wall of the transplanted microcapsules was ruptured, the inner surface showed more increased inflammatory cell and fibroblast infiltration than the outer surface.  相似文献   
4.
于1996年9月~12月在山东省泰安市某幼儿园的两个班使用富含类胡萝卜素的蔬菜进行了干预试验。所选择两个班41名儿童的平均年龄为5.3~6.5岁,其中39%的儿童血清视黄醇低于0.30mg/L,处于边缘缺乏状态。分为2个组:对照组,不改变日常膳食,平均每日每人摄入193g浅色蔬菜(圆白菜、大白菜、土豆、黄瓜、菜花和白萝卜等)和56g黄绿色蔬菜(菠菜、空心菜、胡萝卜和红心红薯等);试验组,平均每日每人摄入238g黄绿色蔬菜和34g浅色蔬菜。结果表明膳食中黄绿色蔬菜对改善学龄前儿童的维生素A营养有重要影响,且安全、廉价。  相似文献   
5.
ABSTRACT: BACKGROUND: The objective of this study was to conduct a systematic review with meta-analysis of studies assessing the association between living in an urban environment and the development of the Crohn's disease (CD) or ulcerative colitis (UC). METHODS: A systematic literature search of MEDLINE (1950-Oct. 2009) and EMBASE (1980-Oct. 2009) was conducted to identify studies investigating the relationship between urban environment and IBD. Cohort and case-control studies were analyzed using incidence rate ratio (IRR) or odds ratio (OR) with 95 % confidence intervals (CIs), respectively. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and assess effects of study quality. RESULTS: The search strategy retrieved 6940 unique citations and 40 studies were selected for inclusion. Of these, 25 investigated the relationship between urban environment and UC and 30 investigated this relationship with CD. Included in our analysis were 7 case-control UC studies, 9 case-control CD studies, 18 cohort UC studies and 21 cohort CD studies. Based on a random effects model, the pooled IRRs for urban compared to rural environment for UC and CD studies were 1.17 (1.03, 1.32) and 1.42 (1.26, 1.60), respectively. These associations persisted across multiple stratified and sensitivity analyses exploring clinical and study quality factors. Heterogeneity was observed in the cohort studies for both UC and CD, whereas statistically significant heterogeneity was not observed for the case-control studies. CONCLUSIONS: A positive association between urban environment and both CD and UC was found. Heterogeneity may be explained by differences in study design and quality factors.  相似文献   
6.
7.
This paper reports a narrow Fano resonance of 3D nanocrescent and its application in the label-free detection of single molecules. The Fano resonance depends not only on the gap size but also on the height. The Fano resonance originates from the interference between the quadrupolar mode supported by the horizontal crescent and the dipolar mode along the nanotip. When the height of 3D nanocrescent is 30 nm, the width of Fano resonance is as narrow as 10 nm. The narrow linewidth is caused by the strong narrow resonant absorption coming from the dipolar mode of nanotip overlapping with the quadrupolar mode of nanocrescent, where the absorption spectra are calculated under a horizontal incident light. The narrow Fano resonance is highly sensitive to a single nanoparticle trapped by the nanocrescent. The wavelength shift increases linearly with the refractive index with the relation of Δλ = 22.10n − 28.80, and increases with the size of trapped nanoparticle following a relation of Δλ = 0.826 × r1.672. These results indicate that if a protein nanoparticle with radius of 2.5 nm is trapped by the nanocrescent, the shift is as large as 4.03 nm.

The narrow Fano resonance caused by the strong narrow resonant absorption is highly sensitive to a trapped nanoparticle.  相似文献   
8.
目的:为了规范药品、保健食品和化妆品检验用原子吸收分光光度计检定结果确认工作,有效提升实验室仪器设备量值溯源管理工作,落实ISO17025实验室认可的相关要求。方法:通过对JJ G694-2009原子吸收分光光度计检定规程和检定证书的判读,结合《中国药典》2010年版、GB 5009.13(15)-2003食品中铜的测定和《化妆品卫生规范》2007版中关于原子吸收分光光度计标准方法的要求,制定了药品、保健食品和化妆品检验用原子吸收分光光度计检定结果确认标准和确认报告。结果:本文阐述的标准和方法可以全面有效地解决药品、保健食品和化妆品检验用原子吸收分光光度计检定结果的确认工作。结论:药品、保健食品和化妆品检验用原子吸收分光光度计检定结果确认标准和方法的研究是对药品等检验机构破解量值溯源结果确认难题的有益探索和有效方法。  相似文献   
9.
In this paper, we report a simple and effective method for the preparation of stable core‐crosslinked micelles after the self‐assembly of thymine‐functionalized polystyrene (PVBT) and adenine‐terminated poly(ethylene oxide) (PEO‐A) homopolymers, and subsequent bioinspired photo‐crosslinking of the thymine units in PVBT. We obtained “graft‐like” copolymers from the interactions of PEO‐A with the PVBT chains through complementary multiple hydrogen bonding in a common solvent (dimethylformamide) after the addition of selective solvents (H2O and MeCN for PVBT and PEO‐A, respectively). Stable micelles featuring PVBT as the core and PEO‐A as the shell were formed via selective solvent pairs; they were clearly visualized using transmission electronic microscopy and staining techniques. The shapes and sizes of the core/shell micelle structures did not change after exposure to UV light, revealing the enhanced dimensional stability of these photo‐core‐crosslinked micelles.  相似文献   
10.
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