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71.
The aim of this study was to proof applicability of hyperspectral imaging for the analysis and classification of human mucosal surfaces in vivo. The larynx as a prototypical anatomically well‐defined surgical test area was analyzed by microlaryngoscopy with a polychromatic lightsource and a synchronous triggered monochromatic CCD‐camera. Image stacks (5 benign, 7 malignant tumors) were analyzed by established software (principal component analysis PCA, hyperspectral classification, spectral profiles). Hyperspectral image datacubes were analyzed and classified by conventional software. In PCA, images at 590–680 nm loaded most onto the first PC which typically contained 95% of the total information. Hyperspectral classification clustered the data highlighting altered mucosa. The spectral profiles clearly differed between the different groups. Hyperspectral imaging can be applied to mucosal surfaces. This approach opens the way to analyze spectral characteristics of histologically different lesions in order to build up a spectral library and to allow non‐touch optical biopsy. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
72.
Being a secreted protein, periostin is a multifunctional matricellular glycoprotein. In vitro, periostin has the ability to promote the proliferation and migration of fibroblasts. Previously, it was demonstrated that periostin is mainly produced by cancer-associated fibroblasts or tumor stromal cells. In the present study, we show that periostin regulates capsule formation in a positive manner and inhibits tumor growth. Consistent with a previous finding, several tumor cell lines did not exhibit expression of periostin in vitro or in vivo; and the growth of tumors that had been allografted into periostin −/− mice was significantly accelerated compared with that of the same kind of tumors grafted into periostin +/+ mice. Immunostaining and biochemical analyses revealed that mature collagen was detected abundantly in the capsules and interstitium of the wild-type-grafted tumors but not in those of the periostin −/− grafted tumors. Moreover, the number of activated tumor stromal cells was decreased significantly in the periostin −/− grafted tumors. Our studies suggest that host-derived periostin negatively regulates tumor growth by promoting capsule formation and by mediating changes in the deposition and organization of the tumor microenvironment coordinated by periostin-producing stromal cells.  相似文献   
73.
复方银杏胶囊镇痛作用及其机制的实验研究   总被引:3,自引:0,他引:3  
目的:研究复方银杏胶囊的镇痛作用及其机制.方法:大鼠电刺激法测定痛阈;用试剂盒比色法测定脑组织中谷氨酸的含量;原子吸收光谱法测定脑组织中钙离子(Ca2 )浓度;免疫组织化学ABC法观察脑组织中N-甲基-D-天门冬氨酸Ⅰ型受体(NMDAR1)的分布.结果:复方银杏胶囊350 mg/kg可显著提高大鼠电刺激嘶叫阈(P<0.05),700 mg/kg显著减少小鼠脑组织中谷氨酸的释放以及脑内钙离子浓度(P<0.05);复方银杏胶囊700 mg/kg、350 mg/kg可明显减少疼痛模型小鼠大脑皮层NMDAR1阳性细胞数(P<0.01,P<0.05).结论:复方银杏胶囊具有良好的镇痛效应,其镇痛作用可能与拮抗NMDA受体从而抑制脑组织中谷氨酸的释放及钙离子内流有关.  相似文献   
74.
目的 探讨科博肽肠溶胶囊对晚期癌症患者的止痛效果。方法 每6h口服科博肽肠溶胶囊280μg/次,常规剂量每天560μg,在用药过程中根据疼痛缓解程度调整剂量由280μg~420μg~560μg递增。结果 68例中、重度癌痛患者,显效41例,有效21例,无效6例,总有效率91.2%,药物最小日剂量280μg,最大日剂量为840μg,所有患者均可耐受,未见有药物依赖性。结论 科博肽肠溶胶囊作为控制中、重度癌痛的药物,其镇痛效果满意,副反应少,服用方便,安全,值得临床推广应用。  相似文献   
75.
摘要 目的:探讨鼻内镜术前应用枸地氯雷他定对慢性鼻窦炎的治疗效果及对患者嗅觉功能和鼻黏膜形态的影响。方法:选取我院2019年1月到2022年12月收治的80例慢性鼻窦炎患者作为研究对象,分为观察组与对照组,各40例。对照组患者采取单纯鼻内镜手术治疗,观察组患者在术前应用枸地氯雷他定治疗1个月后再行鼻内镜手术,对比两组患者的临床治疗效果,治疗前后炎症因子水平,内镜下鼻粘膜形态量化评分,嗅觉功能与糖精试验时间。结果:两组患者治疗总有效率对比无差异(P>0.05);治疗后两组患者IL-6、IL-1、TNF-α相关炎症因子水平均降低,且观察组较对照组低(P<0.05);治疗前两组患者鼻漏、结痂、瘢痕、黏膜水肿、息肉、脓性分泌物等情况内镜下鼻粘膜形态量化评分对比无明显差异(P>0.05),治疗后两组患者鼻漏、结痂、瘢痕、黏膜水肿、息肉、脓性分泌物等情况内镜下鼻粘膜形态量化评分均降低,且观察组较对照组低(P<0.05);治疗前两组患者嗅觉识别阈值、糖精试验时间对比无明显差异(P>0.05),治疗后两组患者嗅觉识别阈值、糖精试验时间均降低,且观察组低于对照组(P<0.05)。结论:鼻内镜术前应用枸地氯雷他定对慢性鼻窦炎具有显著临床疗效,同时能够降低患者术后炎症因子水平,改善鼻黏膜形态,提升纤毛运动功能与嗅觉功能,值得临床应用推广。  相似文献   
76.
王易  刘丹  王莉新 《微生物学通报》2011,38(11):1718-1720
细菌的结构是病原生物学课程教学中最为基础的教学内容.随着科学技术和研究方法的发展,人们对细菌结构的认识也愈加深入.对国内教材普遍采用的细菌“特殊结构”概念提出不同的观点,试与同行切磋探讨.  相似文献   
77.
The three-dimensional ultrastructure ofCryptococcus neoformans was studied by quick-freezing and deep-etching (QF-DE) method.C. neoformans, strain CDC551, was cultured on agar. The viable yeast cells (107 cells) were inoculated into each mouse from the tail vein. Three weeks after the inoculation, the brains of the mice were perfused with fixatives, quickly frozen, freeze-fractured, deeply etched and rotary shadowed with platinum and carbon. In addition, the viable cells ofC. neoformans on agar were picked up and quickly frozen, and replica membranes were prepared as described above. The ultrastructure ofC. neoformans was three-dimensionally demonstrated by the QF-DE method. The capsule was composed of fine meshworks of microfibrils (10–13 nm in diameter), which were directly attached to the cell walls. The capsule of the in vivo yeasts (yeast cells in the brain lesion) was thicker than that of the in vitro yeasts (yeast cells on agar culture). At the outer part of the cell wall, a particle-accumulating layer was observed. This layer in vivo was thicker than that in vitro. Occasionally, the yeast cells were ingested by phagocytes in the mouse brain. Although the cytoplasm of such yeast cells was destroyed, the capsular meshworks were well preserved. The ultrastructure of the capsule was the same both in cultured and phagocytized yeasts in the cystic lesions of the brains. This lack of morphological changes of the capsular meshworks suggests that they are resistant to the digestion by phagocytes. This stability of capsular structures may provide one of the important pathogenic factors in cystic lesions byC. neoformans.  相似文献   
78.
摘要 目的:研究丹蛭降糖胶囊联合胰激肽原酶治疗2型糖尿病早期肾病的疗效及对肾功能、血糖指标的影响。方法:选择2021年1月~2022年7月于我院诊治的60例2型糖尿病早期肾病患者,将其随机分为两组。对照组单用胰激肽原酶治疗,观察组采用丹蛭降糖胶囊联合胰激肽原酶治疗。检测两组的肾功能指标、血糖指标[空腹血糖(FPG)、胰岛素抵抗指数(HOMA-IR)、空腹C肽(FCP)、餐后2 h血糖(PBG)、糖化血红蛋白(HbAlc)和餐后2hC肽(PCP)],且检测两组的超敏C反应蛋白(hs-CRP)水平。结果:观察组的有效率高于对照组(P<0.05);治疗后,两组的血清hs-CRP水平均降低,且观察组较对照组低(P<0.05);治疗后,两组的血清肌酐、β2-微球蛋白、尿素和胱抑素C水平明显降低(P<0.05),且观察组的血清肌酐、β2-微球蛋白、尿素和胱抑素C水平明显低于对照组(P<0.05);治疗后,两组的FPG、HOMA-IR、FCP、PBG、HbAlc和PCP水平均明显降低(P<0.05),且观察组的FPG、HOMA-IR、FCP、PBG、HbAlc和PCP水平明显低于对照组(P<0.05)。结论:丹蛭降糖胶囊联合胰激肽原酶对2型糖尿病早期肾病有显著的疗效,能明显改善肾功能和血糖指标。  相似文献   
79.
Gas vesicle formation and buoyancy regulation in Pelodictyon phaeoclathratiforme strain BU1 (Green sulfur bacteria) was investigated under various laboratory conditions. Cells formed gas vesicles exclusively at light intensities below 5 mol · m-2 · s-1 in the stationary phase. No effect of incubation temperature or nutrient limitation was observed. Gas space of gas vesicles occupied always less than 1.2% of the total cell volume. A maximum cell turgor pressure of 330 kPa was determined which is comparable to values determined for cyanobacterial species. Since a pressure of at least 485 kPa was required to collapse the weakest gas vesicles in Pelodictyon phaeoclathratiforme, short-term regulation of cell density by the turgor pressure mechanism can be excluded.Instead, regulation of the cell density is accomplished by the cease of gas vacuole production and accumulation of carbohydrate at high light intensity. The carbohydrate content of exponentially growing cells increased with light intensity, reaching a maximum of 35% of dry cell mass above 10 mol · m-2 · s-1. Density of the cells increased concomitantly. At maximum density, protein and carbohydrate together accounted for 62% of the total cell ballast. Cells harvested in the stationary phase had a significantly lower carbohydrate content (8–12% of the dry cell mass) and cell density (1010–1014 kg · m-3 with gas vesicles collapsed) which in this case was independent of light intensity. Due to the presence of gas vesicles in these cultures, the density of cells reached a minimum value of 998.5 kg · m-3 at 0.5 mol · m-2 · s-1.The cell volume during the stationary phase was three times higher than during exponential growth, leading to considerable changes in the buoyancy of Pelodictyon phaeoclathratiforme. Microscopic observations indicate that extracellular slime layers may contribute to these variations of cell volume.  相似文献   
80.
Microbial cell surface glycans in the form of glycolipids and glycoproteins frequently play important roles in cell-cell interaction and host immune responses. Given the likely importance of these surface structures in the survival and pathogenesis of Campylobacter jejuni, a concerted effort has been made to characterise these determinants genetically and structurally since the genome was sequenced in 2000. We review the considerable progress made in characterising the Campylobacter glycome including the lipooligosaccharide (LOS), the capsule and O- and N-linked protein glycosylation systems, and speculate on the roles played by glycan surface structures in the life-cycle of C. jejuni.  相似文献   
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